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In an open circulatory system, how is blood moved?
In the mollusks section, the powerpoint mentioned that gastropods and bivalves have an open circulatory system. According to the note, this means that the blood does not travel in vessels. How, then, does blood move? Does that mean that these organisms are simple enough to be able to survive by just pumping blood straight out into the body?
How does this type of circulatory system work?
Thanks!
evamvid

In a closed circulatory system, all of the blood stays within blood vessels or the heart itself.
Organisms that have open circulatory systems, such as arthropods, have hemolymph (a fluid that is essentially a mixture of blood and interstitial fluid). The hemolymph actually does travel in vessels for a very short amount of time, as it is leaving the heart. After this, it goes to the body cavities of the animal and directly bathes the tissues in the fluid in order to deliver oxygen, nutrients, etc.
Hemolymph moves throughout the body when the animal moves. Also, when the heart relaxes, hemolymph is drawn back toward the heart through ostia, or open-ended pores.
So to answer your question, yes, these animals can survive just by pumping hemolymph straight into the body. This is only effective because their body cavities are very small. In humans, an open circulatory system would never work because it would require an enormous amount of work to pump and circulate blood throughout our entire body cavity.


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How do nutrients get to the cells they need to get to?
I understand the basics of digestion. I know that nutrients get absorbed by the microvilli, enter the bloodstream and travel to the liver but after all that, what is the biological mechanism that guides these nutrients to the proper receiving location?

Just dropping this link here for reference - it contains some info on membrane transporters which is of relevance to your question: http://themedicalbiochemistrypage.org/membranes.php

Broadly speaking, nutrients that enter the blood from the gut, and those that are released into the blood by the liver, are available to any cells that require them. So there is no "guiding to the correct location" in the sense that you suggest.
Lipids for example are present in the various lipoproteins and can be acquired from these by all cells. Iron is bound to transferrin, and any cell with transferrin receptors can internalise the transferrin and take the iron. Glucose is available in solution in the plasma, and free fatty acids are bound to serum albumin in the blood. During starvation the liver produces ketones ("ketone bodies") which are taken up by many different tissues/cell types.

Are you saying that myriad nutrients just float along through the blood stream just bumping into myriad receptors at random and when there is a connection, the nutrient will be absorbed?

@max Basically, yes.

Pharmacokinetics must be a fun field! How different a concentration of iron, e.g., do different organs see? Clearly depends on rate of flow vs binding rate...

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Why do our epiphyseal plates close up in our late teens or early twenties?
What causes our epiphyseal plates close up in our late teens or early twenties?
I realize that one's genetics plays the main role in this. I assume there is a gene that controls the epiphyseal plates in our long bones. I guess there would be genes dedicated to every single epiphyseal plate found in our body too. So to rephrase the question:
Why does the gene for our epiphyseal plates turn off in our lates teens or early twenties?

During Endochondral ossification  chondrocytes in the plate are rapidly dividing, newer daughter cells stack facing the epiphysis while the older cells are pushed towards the diaphysis. As the older chondrocytes degenerate, osteoblasts ossify the remains to form new bone.
In puberty increasing levels of estrogen, in both females and males, leads to increased apoptosis of chondrocytes in the epiphyseal plate. Depletion of chondrocytes due to apoptosis leads to less ossification and growth slows down and later stops when the entire cartilage have become replaced by bone, leaving only a thin epiphyseal scar which later disappears. Once the adult stage is reached, maximum height is reached.
Your question addresses the genetics of this process however it is more so regulated by the endocrine system. There has not been a single gene assigned to growth plates, or its regulation, and I find it unlikely that there ever will be.
Rather, endochondrial ossification takes place because of hundreds of genes interacting with each other. If you start to look at genes involved in apoptosis and the estrogen receptor pathway, you will begin to appreciate more the complexity behind the physiology.
I have a hunch you were looking for a gene, that with age just shuts off, or turns on. Recent evidence has show this does in fact happen as methylation may be a candidate mechanism of mediating not only environmental, but also genetic effects on age-related phenotypes.
http://journals.plos.org/plosgenetics/article?id=10.1371/journal.pgen.1002629

Interesting. So maybe this should be another posted question but, what else besides life style choices (food quality, air quality, stress level, exercise) constitutes environmental effects on age-related phenotypes?

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Can sealed epiphyseal growth plates theoretically be restored via epigenetic or genetic methods?
I know that epiphyseal growth plates seal up once people become young adults and that it is currently impossible to restore them to actively produce new bone growth but, is it theoretically possible via genetic or epigenetic means to reactivate them to produce new bone?

I don't know about bone length, that's one for science fiction. What about bone density?

bone density is something else I'd be interested in knowing about but this question is focused only on reactivating the epiphyseal growth plates.


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Feather identification

One of my sister's chickens was killed a few days ago.  This feather was left at the scene of the crime.  The location was Idaho, near Boise.
The death of the chicken leads us to believe it is a hawk or falcon but the vertical brown line has us all scratching our heads.  The current belief is it's from a juvenile, but we can't pick out the type.
Does anyone recognize it?

please add a bit more information like the size of the feather and what time of day/night was the chicken killed and what injuries did it have any information can help identify the bird.

Certainly.  The feather is 5 inches long.  The chicken was killed in the afternoon, the sun was still above the horizon.  While I didn't see the carcass, I was told it looked like it had been pecked over and over.  Likewise, she owns a very large, very grumpy rooster who was missing some feathers and had his comb ripped, meaning it had to be big enough to take on a large, angry rooster who was trying to defend.

perhaps try the feather atlas https://www.fws.gov/lab/featheratlas/idtool.php, or reddit/birdwatching reddit birds of prey it's too specialized for here

It's impossible to say definitively from a picture, but the feather looks very much like that of a Barn Owl (Tyto Alba). This also fits with the geographic location of Idaho.
Take a closer look at the trailing edge of the feather, it appears to have the soft "fluffy" edge typical of most owl feathers.
Here's an example that shows the similarity:
https://www.barnowltrust.org.uk/barn-owl-facts/signs-barn-owl-occupation/signs_feathers-male-female/

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Beneficial effects of the fungi of a termite mound on the diseases suffered by the termites
My motivation to join this Biology Stack Exchange is the article by David Pride that I've read from the Spanish edition of Scientific American, that's Investigación y Ciencia. The article is [1], and I think that is a very good work from the author and editors of this popular science magazine.
Question. I would like to know if the fungi of a termite mound have beneficial effects on health (related to diseases caused by viruses or bacteria) for the termites that live in the termite mound.
I add that Wikipedia has the article Fungus, and what's I evoke with my Question, is about if some species of fungi could live with the termites inside the termite mound and have beneficial effects on the diseases suffered by the termites. I don't know if this question is in the literature, feel free to answer my question as a reference request if you know references answering my question.
References:
[1] David Pride, Los virus de nuestro cuerpo, Investigación y Ciencia, Febrero 2021, Nº 533, pages. 76-83.

I'm mathematician. If you think that you can to improve the post (tags, grammar...) please do it. If you think that the post isn't suitable for the site add a comment that I can to delete it in next few hours. Feel free to add your feedback about the question in comments. Many thanks.

Welcome to Biology.SE. Please take the [tour] and then go through the [help] pages starting with [Ask] questions effectively on this site and [edit] your question accordingly. In particular, questions are best received when they are clear and demonstrate significant prior research (tell us where you've looked for answers, what you do know about the topic). Also, the Investigación y Ciencia article is about human viruses not fungi or termites, so can you please clarify what in that article is relevant to your question? Finally, your last paragraph seems to mostly repeat the "Question" ...

Welcome! To find articles on this try the keywords “termite fungus symbiosis.”

..and mathematicians can develop into truly useful bioinformaticians.

Many thanks for your feedback (the keywords) and the comments of previous users about general information of the site. Next time I improve my posts. Many thanks all for the welcoming @PolypipeWrangler  (I am no longer young to continue studying).

I would like to add a thanking message for you @PolypipeWrangler and your colleagues of the site for this friendly welcoming, I add some subjects that I'm interested (don't related to this post but I share these for the friendly attitude of the users) because are curious, for example the hygroscopic property of honey; the Wikipedia article dedicated to Sepiolite in relation to processes for bacterial transformation, as refers the last phrase of this article dedicated to sepiolite; and I'm interested at the origin of life and diseases,... Isn't required a response, good afternoon to all users

In at least one case termite cultivated fungus produce antibiotics that benefit the termites and protect them from dangerous fungus. Of course just the fungus acting as food is also a huge benefit to the termites.
https://www.nature.com/articles/srep03250

As soon as I can (with score of 15 or more of reputation), I'm going to upvote your answer. I'm going to visit the page of Nature, and I'm accepting your answer.

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If male songbirds fail to learn songs from older males, which makes them less attractive to females, will that species eventually die out?
I recently read that a species of critically endangered song bird (Regent honeyeater) may go extinct if there aren't any older males around for younger males to learn their song. From this article.
But will this species eventually die out because males cannot attract a mate or can scientist use play back recordings (of song) to teach these young males how to sing?

Clearly they can go extinct: "Researchers say a decline in singing culture could drive the species to extinction." There are very few of the birds left; it might be difficult to figure out where to put the speakers to target the sparse males. (That's why the young males aren't hearing the older males' songs: too far apart.) Did you google "can scientists teach male regent honeyeater to sing correctly?" If you didn't, could you please try that, and tell us if you had any luck finding anything helpful? Why or why not? Thanks!

The article you reference is behind a paywall, but I believe I've found the study they're referencing anyhow. You can find it here for free.
To directly answer your question: no one can really answer that right now. That's not to undermine your question. Any population can go extinct when put in certain conditions.
The authors of the paper call for more controlled research,

Experiments in captivity that replicate a range of demographic
scenarios could help improve our understanding of the process of
cultural song erosion and its impacts on fitness and population growth
[42].

I know that's rather unsatisfying, but it's straight from the horse's mouth. That's science for you. But I'll try to entertain you for a bit, because what would a good answer be without a bit of supposition? As I'm sure you've read, it isn't that the birds aren't singing, it's that they're not singing the right song. The authors note

Regent honeyeaters exhibit strong conspecific attraction, once roaming in flocks of hundreds [23]. However, at least four of the interspecific singers were more than 100 km from the nearest known male at the time they were detected.

Which means when they sing the right song, they do a darn good job of recognizing each other. But unfortunately, these guys are too far apart, and as their population density decreases, they're more likely to learn songs from interspecifics (other species). The authors also measured the ability for birds in captivity to learn their own song and they suspect it could cause problems upon release. A scientist teaching a bird to sing might not be a solution either. Sure, we could just stick a speaker out in the woods and let it go all day, but it's kind of like putting a bandage on a sinking ship.
The real issue here is conservation of these guys' habitats, which involves a variety of processes beyond a boombox in the woods. There are tons of questions we still need answers to. For example, if a population decrease results in young birds learning the wrong songs, what causes the population to decrease in the first place? It's a sort of chicken or the egg question. Or, what if we just take the birds and combine their populations? Well, that might be more harm than good. What causes these birds to learn the songs of other species? Are they too smart for their own good? How heritable are the genes that encode these important songs? So on and so forth, you understand.
For more about conservation, and what can be done, check out an example of the Florida panther and what's been done to protect them. Of course, every group is unique in their needs, but just to get an idea of what it takes to conserve a species.

Great literature review from @BrownBag of the original paper. A notable addition to whether the speakers will be effective in teaching the young males the "correct" song brings in the topic of acoustic propagation.
Even if the speakers are placed in the areas with the most young males /and/ are "singing" the correct song, it does not mean all of the song's important features will projecting equally throughout the environment where the young males would be positioned. Consider these three examples:

If air temperature is higher to the East than to the West

There is denser foliage to the North vs the South

There is a highway in the NE corner of the habitat.

All the frequencies of the "correct" song will still not propagation equally under these conditions.
Overall: lower frequencies propagate further than higher frequencies, so a young male further from the speaker may only receive the low frequencies of the song and therefore still learn a low-frequency-only "wrong" version of it.
In terms of the specific examples 1-3 above:
1A) Sound waves travel faster in cooler temperatures, so young males towards the West will have a better chance of hearing the song at further distances to the speakers.
2A) Denser foliage reduces propagation distance by absorbing and scattering sound waves, so young males listening through the leaves (literally) towards the North may learn a diluted version of the "correct" song.
3A) Highway noise masks low frequencies more than high frequencies, so young males positioned closer to the highway (in the NE corner of the habitat) may learn a high-frequency-only "wrong" version of the song.
All these environmental limitations to propagation can shape song over time. They are also not predictable from day to day, so the ideal placement of a speaker could change from day to day.
In terms of time scales of evolution, it is likely that the Regent honeyeater has been able to adapt to temperature and foliage differences over millennia (since they are not extinct yet). But the human-driven effects of masking have occurred on a faster time scale (over decades, not millennia). Therefore, the Regent honeyeater may or may not be able to adapt its song fast enough under the faster anthropogenic pressure and could go extinct as a result.


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Are there any examples of social animals which show collective behavioral change in response to disease?
When Covid-19 happened, collective behavioral changes were taken in order to curb the spread of the virus by the human race. Do things like these happen in other animals as well? Like isolating a person who gets sick and such.

Interesting question. Here we are expected to show the results of our own investigations into a subject here, you can [edit] to tell us what your searches found and where the sticking points are.

Welcome to Biology.SE. As stated by @JiminyCricket we are expected to demonstrate prior research when posting. Please [edit] your question and tell us where you've looked for answers, what you do know about the topic, and where exactly you still have questions. Under researched questions are subject to down-voting and closure. Please take the [tour] and consult the [help] starting with [ask] for details and then delete or edit. ——— For example, I did a quick search and came up with this article.


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Identifying a Texan horned butterfly
I found this butterfly on some late-season bluebonnets in Fort Worth, Texas, this evening.  You can get some sense of scale if you know how big bluebonnets are; the body is probably about the size of my thumbnail, but the 'horn' made it longer.

Great job on providing enough detail for an ID. I've edited your post a bit (including taking out the moth part since the antennae are clearly butterfly-like). One helpful tool for identifications is "Google Lens".

This appears to be an American (or common) snout (Libytheana carinenta).
The "snout" of this butterfly is very distinctive as is the squarish tip of the forewings (the part projecting furthest back to the left in your picture.
Did you see the top surfaces of the wings? They should have had a dusty orange and brown pattern with white spots.
These butterflies are found from Texas to Canada and related species are seen in the Caribbean.

Image: Judy Gallagher CC BY 2.0.

I only saw it perched, so I didn't get to see the top surface, but, as you say, the snout is hard to miss, and the wings also had that squarish tip that you mention, so this seems like it must be it.  Thank you!

You're very welcome :-)


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My bathroom connected scale pretend telling me my total body water level? How could it do that?
Along with a connected watch, I also bought a connected bathroom scale.
Both are giving me plenty of indicators, very extended ones. And sometimes, I wonder where and how they can extract or deduce them.
A simple one: my bathroom scale dares to tell me my total body water level.
The software displays (I've only had the scale for one week) this for my weight:

and this for my total body water:

These two curves don't move in the same direction nor the opposite one.
From what could the total body water be determined and is it reliable?
The scale has so few values about me and I don't see how it could measure total body water.

Welcome to Biology StackExchange! Your scale very likely uses a small electric current to measure the electrical properties of your body. It turns out that water and fat have slightly different electrical properties, which can easily be measured. This is called Bioelectrical impedance analysis and is an established method for estimating body composition. The accuracy depends on the quality of your scale, but also on various other (physiological) factors.

@Domen Thanks a lot! And just for my curiosity, when my scale displays 71.3 kg and 53.3% of total body water level, does it means that I weight "33.3 kg without water"?

Yes. Human body consists of approximately 53 % of water (by weight). Given your weight, you are composed of 38 kg of water and 33 kg of everything else.

@Domen feel free to turn that comment into an answer.

@Domen Yes, it is useful to everyone, and you deserve the answer reward for it.

Your scale exploits the difference in electrical properties of water and fat to measure the composition of your body. This method is called bioelectric impedance analysis (BIA), and it is usually used for  estimating the composition. There exists several other, more accurate methods, such as weighing a person under water (hydrostatic weighing), dual-energy X-ray absorptiometry (DXA), CT, and MRI – the last two usually regarded as the gold standard1.
The basic principle of BIA is to use a small electric current through your body and measure its electrical response. Roughly speaking, cell membranes can be regarded as electric capacitors, water as a good conductor, and fat as a bad conductor. In the simplest model, human body is therefore represented as a resistor and a capacitor in a series ($RC$ circuit), and electrical impedance (combination of electrical resistance and electrical capacitance) is measured at a single frequency (e.g. $50\;\mathrm{kHz}$).
The measurement together with your physical dimensions (height and weight), your age, and your gender – all of which you had to disclose to your bathroom scale – are then put into a BIA formula, which the manufacturer has obtained by calibrating its device with one of the more accurate methods. An example of such formula2 is
$$FFM = (0.34 \times10^4) \frac{h^2}{Z} + 15.34  h + 0.273  m - 0.127t + 4.56 S - 12.44,$$
where $FFM$ is fat-free mass, $h$ body height (in meters), $Z$ electrical impedance (in Ohms), $m$ body mass (in kilograms), $t$ age (in years), and $S=0$ (female), $S=1$ (male).
The accuracy of BIA depends on the quality of the device, but there are also other important factors, such as the environment, ethnicity, phase of menstrual cycle, and underlying medical conditions3.

https://jim.bmj.com/content/66/5/1.10
https://www.ncbi.nlm.nih.gov/labs/pmc/articles/PMC4608267/
https://www.ncbi.nlm.nih.gov/labs/pmc/articles/PMC2543039/


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Found a bug looks like a true bug but it has a mowhak
It looks strange found it today what is it?

Looks like some kind of treehopper.

Welcome to the site. Please take a look around the [help] and take a [tour] to see what is considered a good question.  For species identification, we at least need a location (not just country - more specific) and at least one high resolution photo,  preferably several as ID is tricky without being able to see all the parts of the insect. Leafhopper of some sort, which one, I don't know - there are ~20,000 species worldwide.

Please [edit] to include your location, or this is just not detailed enough to narrow efficiently.

This inscent is a treehoppper or thorn bug (Membracidae). They belong to the Auchenorrhyncha.
Membracidae have a distinct transformed and enlarged (sometimes larger than the body itself) pronotum that often forms unusual structures - such as the "mowhak" on the photo or horns as the buffalo treehopper. These unusual shapes are thought to be camouflage or mimicry.
Besides, their body shape is typical for planthoppers: an inclined head, their "rooftop" wings, a proboscis to suck plant sap, short antenna and relatively short, but powerful jumping legs.


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Evergreen ornamental shrub identification
These images were taken in the middle of April in central Poland.
Plants are between 0.5 and a meter tall, and around a meter in diameter.

Welcome to Biology.SE! I've edited your text to make it clearer (e.g. I assumed that state was meant to be date) — please check to make sure I haven't changed your intended meaning. I'm very short on time right now, but this looks like a laurel of some sort (genus: Prunus), which are common garden shrubs.


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Is this insect a bedbug?
I just found this bug on our bed. So even though it is literally a bedbug… is it actually a bedbug? We have never had an issue before and no signs of bites. But finding this worries me now…

Have you searched for pictures of bedbugs? Does yours look like any of them? What makes you think it might be a bedbug?

Yes, I’ve searched for pictures of bedbugs. As someone who isnt a bug expert — honestly, its hard to tell just by looking at pictures. I believe someone who knows bugs well would have an easier time identifying the pictures I submitted, which is why I asked.

Does this answer your question? This is a common question here.


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Need assistance identifying palm-like tree
I need assistance identifying what type of palm-like tree we've been growing. My husband's Grandfather brought the original plant home in 1974 from Florida and we've been growing and repotting them for the last 25 years. The leaves are incredibly sharp. They are very hardy and survive Ohio winters living in the basement. We have had them grow up to 5 feet in height. They produce numerous new plants each year.

Not a palm, looks like a Dracaena. Do a search for Dracaena images and you'll find something close -- Lots of hybrids out there.

This is definitely not a palm species as these all have leaves either deeply divided or coming off as leaflets from a stalk.
I think this is a Yucca (Asparagaceae) species. Yucca and the very similar looking, and closely related Dracaena are very similar in appearance, both (depending on species and cultivar) often have sharp, spiky, inflexible leaves coming directly off a stem (i.e. no stalk).
In the case of Dracaena, the leaves fall off the stem leaving a diamond/triangular scar, but Yucca tend to retain the dead leaves and have the new leaves push through the dead ones.
Dracaena stem:

Image attribution: Auckland Museum, CC BY 4.0 https://creativecommons.org/licenses/by/4.0, via Wikimedia Commons
Yucca stem with dead leaves (note similar scar pattern):

Image attribution: Stan Shebs, CC BY-SA 3.0 https://creativecommons.org/licenses/by-sa/3.0, via Wikimedia Commons


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Can anyone identify this fish?
I saw it in the sea very close to the beach in front of Starfish Hotel in St Lucia. It had some spines along its back and it seemingly had fins on each side that split open into 4. It used its front two fins to dig through the sand. It had white spots, and the main colour of it was very dark brown - black. The fins on the fish were very thin and flimsy-looking.
From tail to head was probably around a foot long, and the end of one fin to another was around 15-20 cm.
Here is a link to a video I took seeing as the picture may not be clear enough- https://drive.google.com/file/d/1PzjgzAaK6B51jg9HHNO4SQyorepsdKLB/view?usp=sharing

Welcome to Biology.SE! It will improve your chances of getting an answer if you include an estimate of the size of the organism. Clearer photos would also be very helpful, but I understand that may not be possible. Please [edit] your post to include this essential information. (For future reference, identification questions should always be given the species-identification tag.) ——— Please also take the [tour] and then go through the [help] pages starting with [Ask] questions effectively on this site. Thanks!

The array of fins brings Lionfish to mind, bit I have no idea if this is what they look like from above.

@bob1 I just looked up images of them from above. It doesn't look like it, if you ask me. It almost has a pufferfish-like body.
https://media.sciencephoto.com/image/c0153618/800wm/C0153618-Lionfish_from_below.jpg

Yeah, and I haven't been able to find a list of fish species with pictures from the area either... lots of sport fishing species, but nothing for the in-shore or estuarine.

Based on the location, size, behavior, and shape (particularly of the pectoral fins) this appears to be a flying (or helmet) gurnard (Dactylopterus volitans) with its "wings" folded.
These range of these fish includes the Caribbean and they are known to use the forepart of their pectoral fins (i.e. the free extra 'fin' near their head) for "exploring the bottom" 1-3, which fits the behavior you described.
The size is also reasonable since they are said to reach up to 50 cm in length.
Image below for comparison — note these fish are described as being highly variable in coloration.

Image © slebris from iNaturalist some rights reserved
References:

https://fishbase.mnhn.fr/summary/1021

Roux C; Dactylopteridae. In: Miller, P. J., Whitehead, P. J. P., Bauchot, M. L., Hureau, J. C., Nielsen, J., & Tortonese, E. (1986). Fishes of the North-eastern Atlantic and the Mediterranean. Vol. III. Richard Clay Ltd, Bungay, United Kingdom.

Davenport, J., & Wirtz, P. (2019). Digging with ‘hands’: observations of food capture in the flying gurnard Dactylopterus volitans (Linnaeus, 1758). Journal of Natural History, 53(41-42), 2489-2501.

Excellent choice, It didn't even cross my mind that gurnard would be present there.

@bob1 —— Thanks — gurnards do have a surprisingly wide range. I actually stumbled on this while I was researching a comment suggesting the OP look on iNaturalist since they clearly weren't going to get an answer here!


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What are the small white dots in an onion cell seen under an electron microscope?
We had to use an electron microscope in class for an assignment and used onion cells. On the 40x and 100x magnification there are tiny white dots and I was wondering if someone could tell me what they are? I have to draw them up and label what I can see but i'm just not sure and I don't want to do it wrong. I saw something that said it could be granules of inclusion but i'm thinking it is probably bacteria or air pockets? I was also wondering if someone could tell me what these bean shaped things are? Or any other organelle that you might see, it would be very appreciated!
I'm sorry the photo isn't great, I could only add one photo and I struggled to find one that showed everything that I was asking, so I hope you can see the tiny white dots I mentioned in my question.

We had to use an electron microscope in class — do you mean a light microscope?

Welcome to Biology.SE. This is not simply an answer site, but instead a site that promotes self-learning with some expert help. Consequently, questions that show little or no prior research effort are off-topic on this site as are "homework" questions unless you have shown your attempt at an answer. Please [edit] your question and tell us where you've looked for answers, what you do know about the topic, and where exactly you still have questions. Please take the [tour] and consult the [help] starting with [ask] for details.

Are you sure you were using an electron microscope?  They're quite complicated (and expensive (average $294,000, per Google), and generally used for much higher magnifications.  I also think you need specially treated specimens, not just a slice of onion.  To this non-expert, those white spots look like thin places in your sample, seen in a light microscope.


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How many cells are there in C. elegans in each hour of its life?
I'm a high school student planning to write a math essay to model changes in the number of cells in a living organism over time. C. elegans is the only organism that I know with a known number and lineage of cells. I found the full lineage of cells in C. elegans here, which is plotted in respect of time. However, counting the number of cells in those diagrams is impractical. So, is there a summarized database for the number of cells in each hour in the life of C. elegans?

Could you clarify " write a math essay to model changes in the number of cells in a living organism over time" -- what kind of essay or model?

The lineages provided at WormAtlas include references to the original publications. Concerning the embryonic lineage at the top of the page, the corresponding paper was published in 1983.1 Looking at that publication, we see that the authors provide a summary figure depicting nuclei counts over the course of 800 minutes, from the first embryonic cleavage until hatching:

FIG. 4. Marker events and count of living nuclei during embryogenesis. Fertilisation is normally at -50 min. Note that the comma stage is defined in a precise way, as the moment at which the ventral surface of the tail lies perpendicular to the long axis of the egg.

Post-embryonic nuclei counts for young worms and adults are given in Tables 2 and 3 of a 1977 publication by the same first author.2 I can find no data on hour-by-hour cell counts over the interval of an adult worm's lifetime, though such a dataset might be out there.

References

Sulston JE, Schierenberg E, White JG, Thomson JN. The embryonic cell lineage of the nematode Caenorhabditis elegans. Dev Biol. 1983 Nov;100(1):64-119.
Sulston JE, Horvitz HR. Post-embryonic cell lineages of the nematode, Caenorhabditis elegans. Dev Biol. 1977 Mar;56(1):110-56.


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What is the name of this bird from Tanzania?

I took this picture in late 2018 in Tanzania. The Birds of East Africa book does not include it and I've been unable to identify it looking on the web. Can someone help me identify it, please. Thank you!

That looks like a knob-billed duck.
Their range includes Sub-Saharan Africa, India, and Southeast Asia.

Picture source


text:
Is molecular oxygen (O₂) consumed in any process (in humans) other than acting as an electron acceptor for the ETC?
I know that molecular oxygen (O2) serves as the electron acceptor in Complex IV of the electron transport chain, which maintains the proton gradient that produces ATP for, as far as I know, every cell in the human body.
Is this the only reason we need molecular oxygen for life, or are there other vital functions (i.e. necessary for life) that molecular oxygen serves within the human body?
Edit
For clarification, there are probably well over a million oxygen-containing compounds, from water all the way up to the largest proteins, which perform repeatable roles in basically every system of the body. But in cases where oxygen is exhausted, specifically consumed requiring a continuous supply of new oxygen, what roles does oxygen serve with the exception of serving as electron acceptor in Complex IV of the electron transport chain?

Are you asking about molecular oxygen, rather than all the roles of oxygen containing compounds? I'm not sure why you're getting the downvotes, but maybe clarifying this will help you get a more favorable response ...

@tyersome The original intention was to capture purposes served that consume oxygen in a one-off process, rather than incorporating it into components that can be reused. The significance here is that the vast majority of the oxygen balance in the body will go into processes that consume oxygen, rather than incorporating it. Yes, oxygen-containing compounds will eventually degrade or be removed from the body and require replacement, but in studying oxygen balance, it is these consuming processes that hold the most sway, and I'd like to gain a better understanding of these processes.

So, would it be accurate to say that the question you want to ask is something like:
'Does molecular oxygen (O₂) have any roles other than as an electron acceptor for the ETC?'

@tyersome Not necessarily, because molecular oxygen can be transformed before it is consumed in a different form, so that would be just slightly too specific a phrasing

OK, but the question as written isn't specific enough since it would seem to include  roles of water (and almost every biomolecule since they mostly contain oxygen) — i.e. all of biology! ——— How about: 'Is molecular oxygen (O₂) consumed in any process other than by acting as an electron acceptor for the ETC?'

@tyersome Works for me! Feel free to make the edit so you get the credit

Molecular oxygen also has roles in antimicrobial defense1,2. Specifically macrophages use O2 to create cascades of reactive nitrogen intermediates (RNI) and reactive oxygen intermediates (ROI; aka ROS) — these compounds have antimicrobial effects.
The RNI cascade starts with nitric oxide (NO) and is catalyzed by a nitric oxide synthase, which converts arginine and O2 into citrulline and NO.
The ROI cascade starts with superoxide (O2•-) and is catalyzed by a NADPH oxidase, which transfers an electron from NADPH to O2 creating superoxide.
Figure 1 from2 gives an overview of these reactions:

Legend for figure 1:

ROI and RNI production in mammalian cells via phox and NOS: parallel but connecting paths. Nitroxyl anion (NO−), a one-electron reduction product of nitric oxide (•NO), is unlikely to arise from •NO under physiologic conditions, but is considered by some investigators to be a primary and more toxic product of NOS. Reaction of RNI with cysteine sulfhydryls can lead either to S-nitrosylation or to oxidation to the sulfenic acid, as well as to disulfide bond formation (not shown), all of which are potentially reversible. Peroxynitrite anion (OONO−) and peroxynitrous acid (OONOH) have distinct patterns of reactivity, but for simplicity, the text refers to both as peroxynitrite. OONOH spontaneously decomposes via species resembling the reactive radicals, hydroxyl (OH•) and/or nitrogen dioxide (•NO2). When L-arginine is limiting, NOS can produce superoxide (O2⨪) along with •NO, favoring the formation of peroxynitrite.

References:
1: Weiss, G., & Schaible, U. E. (2015). Macrophage defense mechanisms against intracellular bacteria. Immunological reviews, 264(1), 182-203.
2: Nathan, C., & Shiloh, M. U. (2000). Reactive oxygen and nitrogen intermediates in the relationship between mammalian hosts and microbial pathogens. Proceedings of the National Academy of Sciences, 97(16), 8841-8848.

This is very interesting. However the text under the figure makes the figure itself unreadable on my phone. Could you possibly separate the two?

@David — Gladly. Does this work better?

Yes. That’s fine. Thanks.


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How can a small bug dart around in a slug's slime?
Last year I saw a large slug in the garden, and when I looked closer there was a small creature moving around rapidly, and I mean really fast (hence my use of the word "dart" in the question title - it was no exaggeration!), on the slug's surface below the slime.
What could this creature have been, and how on Earth could it have moved so fast through the slug's sticky slime?

Welcome to Biology.SE. Please take the [tour] and then go through the [help] pages starting with [Ask] questions effectively on this site and [edit] your question accordingly. In particular, your question isn't clear. To identify an organism we need: a detailed description (preferable including clear photos), location, size, and appropriate tags. Also try not to leap to conclusions (e.g. that this was a parasite).

Most likely a mite, I have seen these before.
They can move (swim) faster than the slug.
Probably Riccardoella oudemansi since it is the only slug mite I can find a mention of.
Article on similar snail mite below.
http://en.wikipedia.org/wiki/Riccardoella_limacum


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Found this under a rock at the beach, removed it carefully and couldn't find any other bones, must be a marine mammal of some sort
Does anyone know what this is? I know this is not a land mammal because [details needed].

Unknown skull found under rock at beach.

No sign of eye sockets or jaw with teeth.

I have no idea what this is. Couldn't find any other bones.

How are you confident it is not a land mammal?  My first thought was a badger skull, but I do not think it is.

Perhaps a goat or sheep that has fallen of a cliff. The beach near me has lots of bones from farm animals who died from misadventure.

It's not fossilised either

you will not find eye sockets as you think of them in any marine mammal skull, the eye socket is mostly soft tissue.

A location in the world would be helpful for ID. Species present can vary widely depending on location.

A reasonable match for many features, bearing in mind the incompleteness of the skull is that of the South African Fur Seal (AKA. brown fur seal, Australian fur seal).:

Carolyn Stewardson, Tania Prvan, Meÿer MA, Raymond J Ritchie Copyright status unknown, fair usage via Researchgate
Shown here are views of an adult male of 10 years, the parts circled are those present in your specimen. The slight brow-ridge present on yours is just visible on the bottom plate.
The marked difference between your specimen and this one is the presence of sutures between parietal and frontal bones, which seem to be fused on yours indicating an older specimen (perhaps up to 30 years), but:

Suture age was not a good indicator of absolute age or age group

It's also difficult to tell the match of the slope of the skull bones away from the centre line particularly the parietal - which may be a match or not.
Submitted until a better match comes along.

Almost an exact match to the image, and the nuchal crest on the OP's skull is definitely that of a seal


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What is meant by "Common descent"?
"Common descent is a concept in evolutionary biology applicable when one species is the ancestor of two or more species later in time." (Wikipedia)

[Credit:https://bio.libretexts.org/Bookshelves/Introductory_and_General_Biology/Book%3A_Introductory_Biology_(CK-12)/05%3A_Evolution/5.12%3A_Phylogenetic_Classification (I added the letters to the common ancestor nodes)]
Does this mean that Species 1 and 2 have a common descent which is (A), but Species 1 and 3 do not, even though they share a common ancestor which is (B)?
I was thinking that "common descent" means the immediate previous ancestor. After all, it's a relative matter and there will be a common ancestor at some point. There has to be a term for that other than "just previous common ancestor".

Welcome to Biology.SE. You've done a good job with laying out a clear question, but the question itself seems quite naïve. In addition, the way you've worded this odd — common descent isn't an individual it is a relationship! (Please fix this.)  I also encourage you to check out some of the online resources available for learning more about evolution. For example, this a useful introduction to evolutionary theory from UC Berkeley. ——— I'm going to edit your post, but please check and make more changes as needed.

The Wikipedia definition is suitable to say that species 1 and 3 share common descent.

Common descent is a concept in evolutionary biology applicable when one species is the ancestor of two or more species later in time.

Any node in a (fully bifurcating) tree that is an ancestor to more than two tips will necessarily contain tips that are also descended from some other node.
OP is correct that "there is a common ancestor at some point," and there is strong evidence that all cellular life arose by common descent from our most recent common ancestor.
In practice, the term is usually limited by context. For example, many more relevant comparisons can be made between roses and apples, than between roses and dogs, even though the ancestor of animals and plants did once exist. In a conversation about energy procurement it wouldn't make sense to reference the common descent between roses and dogs; but in a conversation about, say mitosis, it might.
The term "related" suffers similar ambiguity.
As the figure shows, two species can share many "common ancestors," so it may be necessary to specify the "most recent common ancestor." In the figure, both A and B are common ancestors of 1 and 2, but A is their most recent common ancestor.
B is the most recent common ancestor of 1,3, 2,3, and 1,2,3.
The thick black line coming down from B in the figure represents the connection to B's ancestors. All of those ancestors are common ancestors of 1,2,3, but none are the most recent common ancestor of 1,2,3.
The most recent common ancestor of cellular life is the last universal common ancestor.
OP may want to review the term clade for a slightly more precise way to talk about related species. A clade is a group composed of an ancestor plus all and only its descendants.
In the figure:

1 and 2 form a clade with A.
1, 2, 3, A, and B form a clade.
1 and 3 (excluding 2) do not form a clade.

Indeed, I think it's easiest to think about using family relatedness as an analogy; you're related both to your parents and to your 8th cousins four times removed. In the context of life on earth, it's relevant that people are related to fruit flies; in the context of social behaviors it may only be relevant to consider primate relatives.

Thanks for your help, in "clade" wiki page, i found this "last common ancestor". Please edit your answer to include how last common ancestor can be applied to the figure in my example. Is it true to say that Species 1 and 2 have the same last common ancestor but Species 1 and 3 do not have the same last common ancestor

https://en.wikipedia.org/wiki/Most_recent_common_ancestor

This is good, but I think it would be helpful if you addressed the OPs misuse/misunderstanding of "common descent". They seem to think this term refers to an individual species (i.e. that it is synonymous with some type of ancestor) rather than referring to relationship or process ...

I figured it out my self from the answer, that all these terms: "common descent", "common ancestor" and "last common ancenstor" are being used in some abstract way or relative way, rather than to specify  a single one.

@Bowel "Common descent" is a bit abstract; "last common ancestor" a little less so, but the important word there is common. Your last common ancestor with a sibling is your parent. Your last common ancestor with a cousin is a grandparent. Etc. Something similar works with species.

B is the ancestor of 1,2 and 3.  Why do you think that is not an example of common descent between 1 and 3?

I was thinking that "common descent" means the just previous ancestor. After all, it's relative matter and there is a common ancestor at some point. There has to be a term for that "just previous common ancestor".

@Bowel Species are not well defined, especially in time, so "just previous common ancestor" is not a useful category and can't really be identified.


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What kind of hawk is in this picture?
I found this hawk(?) sitting on a fence near a small duck pond with a fountain near my workplace in Fort Smith, Arkansas, USA. There are some wooded hills (deciduous) nearby. It let me get within 3 meters or so before flying up to a tree across the pond. Based on measurements made of the fence it was sitting on, I'm guessing a height of 50 cm (20 inches) head to tail, I assume it'd have a wingspan of 60-70 cm perhaps (24-28 inches).

My best guess it either the Red-shouldered Hawk or Red-tailed Hawk. Unfortunately, I couldn't get a good picture of its back/tail. Any idea what species this is? I came across the bird during winter.

Any guess on the height or wingspan? (just for completeness sake).

@theforestecologist Thanks for the tip. I updated the photo with measurements of the fence and included my guesstimate for height/wingspan.

It looks very much like an immature red shouldered hawk.

Immature Red-shouldered Hawks can be tricky to identify. Immature Red-tails show a belly band and are less heavily marked on the upper chest than young Red-shouldered Hawks.

Red shouldered hawks are smaller and like deciduous forests, like perching on wires, branches, etc. Red tailed hawks are usually birds of open spaces. They hunt from lower down than red tails, and they're often found near water (especially rivers and swamps), as they like frogs and snakes.

Look for Red-shouldered Hawks in deciduous woodlands, often near rivers and swamps. They build stick nests in a main crotch of a large tree. During migration, Red-shouldered Hawks often move high overhead along ridges or along the coast.

Limited to a phone for a while and can't do much (I'm a dinosaur) but info and pictures here.

I'm not sure if the white eyebrows lean towards the red-shouldered more than red-tailed hawks (which appear to be that case from the guide you posted).

@Wayne Werner - I agree that the white eyebrow leans more towards a red-tailed, but if you look at a lot of pictures, some red shouldereds have white eyelines, and the size, chest markings, and habitat all point more to a red-shouldered. They aren't big. I surprised an adult red shouldered eating a snake on my driveway (in the woods). They're quite a bit smaller than red tailed hawks (who used to eat my guinea hens.)

A local outdoorsman also pointed out the possibility of it being a Sharp-shinned Hawk or Cooper’s Hawk. Not sure how good of a match those are, but thought I'd mention it.

@Jeff Bridgman - I know nothing about Sharp-shinned Hawks, but the shape is not quite right for a Cooper's Hawk.

Sharp Shins are much smaller , close to the size of a robin.

Red shoulder will hunt from a perch ( as shown). Rare for a red tail.


text:
Help with gene linkage and mapping!
Here's an interesting question I've been trying to figure out:

My annotations are in red. So far, I've figured out:

We know 630 colonies survived when plated with ACD antibiotics...meaning they picked up the a/c/d resistance alleles, but remain wild-type for the b allele. The genotype would be "a b+ c d". Because SO MANY (630!) colonies seemed to inherit a/c/d together, and b completely separate from them, I would say b is the gene quite distant from the 3 other genes.

However, I've unsure about how to proceed and determine the probably order of the 3 others genes: a, c, and d.
Here's my hunch: B--------------------C-D-A.
I'll explain:

Well, I looked and saw 942 (many!!!) picked up A/D together. So A/D are probably adjacent.
Then, 786 (many, but fewer) picked up C/D together. So C is further from D than A is far from D. The question becomes: is it "C---A-D" or is it "A-D---C"?
The insight comes in with 640 (still fewer) picked up A/C together. That means A is actually quite FAR from C, because more distance = more recombination events that could split them up. So between the "C---A-D" or "A-D---C" listed above, it's more likely "A-D---C".
Okay! We know B is far from the other ones, BUT is it like "B-------ADC", or is it like "ADC-------B"? Well, let's look: picked up B/C together is 51, but picked up A/B together is only 46. That means A is a little FURTHER from B than C is further from B, since 46 < 51.

This led me to my proposed answer: that the order is "ADC---------B", or if you just flip it around, its equivalent: "B---------CDA".

How's my reasoning? This stuff can be pretty confusing; am I approaching it from the right angles? Thanks so much; really appreciate it!

You were never told that all the genes were on a single plasmid. I think you should treat all those counts < 50 as essentially zero; cells pretty much never get both the ACD and the B plasmid; they get one or the other.

I think your reasoning is sound and your ordering very likely, but I wouldn't feel comfortable with deciding the side B is on. Actually, it's more than that: I think that by using basically the same number (~40) for everything that includes B, they want you to come to another conclusion.
Unlike eukaryotic cells undergoing meiosis, there is no crossing over in bacteria taking up DNA from the surroundings. Therefore, it shouldn't be possible for the cell to inherit A, B and C but not D, which is in the middle. Simply, from my understanding of the "experimental" setup, they added antibiotics A, B and C, so they have to assume the bacteria are wild type for D. However, it's basically for sure that those ABC-resistant colonies are also D-resistant.
Still, your reasoning is correct: comparing BC and AB should give you the side B is on, since the break could have been inside of the 3-gene cluster. However, the numbers are very close, and the "AB" and "BC" phenotypes are probably ABCD anyway, making the small difference even less meaningful (the true AB and BC are lost because they are mixed with the many ABCD).


text:
What does it mean for there to be no correlation between phylogenetic independent contrast?
I am testing the correlation between two physiological parameters in plants using the pic function in R. I am a bit stuck on the interpretation of the phylogenetic independent contrast (PIC). Without considering the PIC, I got a significant correlation, but there is no correlation between the PIC. What does the absence of correlation between the PIC mean:

the correlation without PIC is the effect of phylogeny

OR,

There is no phylogenetic effect on the correlation.

Thank you

Welcome to Biology.SE! Can you add information about what tools you are using to do your analysis? ——— Please also take the [tour] and then go through the help pages starting with [Ask] questions effectively on this site. Thanks!

Hello,  I am using the pic function in R

Comments are ephemeral, so in the future please edit your question to include that kind of information — that should increase your chances of getting an answer.  In addition, the Bioinformatics site might be a more appropriate place for this type of question, especially since it isn't getting any response here.

Your first option is the correct interpretation. The correlation you observe in the raw data is the effect of phylogeny.
Without using PICs, you might expect to see phylogenetic autocorrelation, i.e. your raw data correlate as a function of the amount of shared evolutionary history between different species. Using PICs is one way of testing whether the correlation still exists when the effect of phylogenetic autocorrelation is removed. This is exactly what you observe—you see the correlation in raw data (which are not phylogenetically independent) but it disappears when you use PICs. Without knowing any details of your study beyond what's in the question, it sounds like a textbook case of phylogenetic autocorrelation.
The PIC method originates with Felsenstein (1985). I'd encourage checking that paper out for further details on the method and interpretation of the results.


text:
what is this marine creature?
I found this creature floating in the Mediterranean Sea, probably dead.
I tried looking it up in the Marine Species Identification Portal but I couldn't find anything like that. It looks like some kind of jellyfish or hydrozoan.

This is a blue button jellyfish! they eat zooplankton and are usually found drifting along on currents
they aren't true jellyfish and just like a jellyfish have no blood, brain or nervous system. they aren't usually toxic enough to hurt but can cause irritation to the skin.
they live in warm waters off of Europe and in the golf of Mexico and the Mediterranean.
they are hermaphrodites and have both male and female reproductive parts. they lay eggs which turn into polyps
here is a website I found all about them as I'm not extremely knowledgeable on this species.
https://www.thoughtco.com/blue-button-jelly-porpita-porpita-2291819

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text:
Why don't anti-viral drugs like "Acyclovir" work against coronaviruses?
I've always used Acyclovir to treat cold sores, why doesn't it work on other viruses?
How do coronaviruses differ from herpesviruses?

Aciclovir specifically targets HSV-family viruses.
It is metabolized by a viral-specific enzyme into an inhibitor of the specific DNA polymerase expressed by the virus:

in infected cells, HSV or VZV coded thymidine kinase facilitates
  the conversion of aciclovir to aciclovir monophosphate, which is then converted to aciclovir triphosphate by cellular enzymes. Aciclovir triphosphate acts as an inhibitor of and substrate for the herpes specified DNA polymerase, preventing further viral DNA synthesis.

https://www.ebs.tga.gov.au/ebs/picmi/picmirepository.nsf/pdf?OpenAgent&id=CP-2009-PI-00595-3
Other viruses don't express these specific enzymes, and even if they have similar enzymes they may not interact the same way with the drug. Even within the herpesvirus family, the drug is not equally effective against every virus.
Coronaviruses are RNA viruses, so even though the drug is not effective for DNA viruses outside the herpesvirus family, coronaviruses are definitely not going to be affected because they don't even have a DNA polymerase to inhibit.


text:
Can you be immune to a coronavirus?
Can one be immune to the new coronavirus?
Another question is what is the exact definition of "being immune". Does it mean that even when the virus enters my system, it cannot multiply?

Does this answer your question? Human Immune Response to COVID-19 Virus

It is hypothesized that exposure to and recovery from SARS-CoV-2 (as with other coronaviruses in humans) would generally result in short-term immunity to this strain, but we do not yet have data on this:

However, according to Dr Stephen Gluckman, an infectious diseases physician at Penn Medicine and the medical director of Penn Global Medicine, who spoke to the outlet, it seems likely that having the disease once results in immunity in most individuals - as is seen with other coronaviruses.
“Coronaviruses aren’t new, they’ve been around for a long, long time and many species - not just humans - get them,” he explained. “So we know a fair amount about coronaviruses in general. For the most part, the feeling is once you’ve had a specific coronavirus, you are immune. We don’t have enough data to say that with this coronavirus, but it is likely.”
This means that people who initially recovered are more likely to relapse rather than get reinfected with the virus.
According to one study, people with mild infections can test positive for the virus by throat swabs “for days and even weeks after their illness”.
But, that doesn’t mean it isn’t possible to contract the disease again, especially in those who are immunocompromised.
“The immune response to Covid-19 is not yet understood,” the Centers for Disease Control and Prevention (CDC) explains. “Patients with MERS-CoV infection are unlikely to be reinfected shortly after they recover, but it is not yet known whether similar immune protection will be observed for patients with Covid-19.”

Coronavirus: Can You Get Covid-19 Twice Or Does It Cause Immunity?

It is also hypothesized (in humans) that previous exposure to coronaviruses may enable immunity to certain other highly related strains:

These data indicate that challenge immunity to coronaviruses is strong, but highly virus strain-specific.

Virus strain specificity of challenge immunity to coronavirus., Archives of Virology (1989)

But these are all examples of adaptive immunity - not innate.

No, you cannot be immune to the virus, if you haven't been in contact with it before. You are also not immune to the influenza viruses (flu), you just happened to not contract any of them.
Simply speaking, being immune means that your immune system knows the specific virus and can disarm it effectively. But the immune system has to learn to recognize and how to fight a pathogen first. That's the adaptive immune response. It is build once you encounter the virus for the first time, but can also be activated by a vaccine. Having immunity enables your body to fight off the virus, before it can harm you or spread further.
How sick you get from a pathogen the first time around depends on how fast or strong your immune system can build immunity and on your innate immune response. None of this works perfectly. Even with immunity you can still get sick.

In other words, "Yes, you can be immune to the virus, but only if you have been in contact with it, and some time has passed." Then, you are likely to develop immunity.

(..or received vaccine against it.)   If you've never had the flu, it doesn't mean you are immune to the influenza viruses (flu), you probably just happened to not contract any of them.  But throughout the tree of life, some parts of the tree, including subspecies, do not suffer from certain infectious diseases that other parts do.  -Good edits?

The question was worded differently before people edited it. It was about having some "natural" immunity without exposure, because they also never got the flu.. I just wanted to help a worried person. The reality is more complicated and some data now suggests that there is actually the possibility of a "cross-immunity" from our other coronaviruses.

The CCR5-Δ32 mutation (2 deletions) which interferes with HIV might offer "immunity" to the virus causing the pandemic. -- This was the mechanism the experimental CCR5 antagonist Leronlimab (IgG4 mAb) may have accomplished with Covid-19 for several patients.

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text:
Cystic Fibrosis Genetic Risk Determination
Let's say Jane has Cystic Fibrosis and we know her brother doesn't. What are the chances of her brother's future child having CF? (The chances of Cystic Fibrosis in the general population can be taken as 1 in 25)
My apologies for the very incomplete question, this was all I could remember of the actual question.
And the solution went like something along the lines of:
Possibility of Jane's brother's partner having CF: 1 in 25
Possibility of Jane's brother being a carrier: 2 in 3
And this is the part that I am not getting. For me, Jane's brother could only have a 1 in 2 chance of being a carrier (Cc or CC). But the solution went CC, Cc or cC-- this last one, cC, how is that possible? If it's a recessive trait, do we not write the dominant one first? Then how could there be cC and Cc as two separate possibilities?

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And this is the part that I am not getting. For me, Jane's brother
could only have a 1 in 2 chance of being a carrier (Cc or CC).

Wrong, because those are not equally likely.
There are 4 equally likely possibilities for any of Jane's siblings:
inherit good allele from Mom, good from Dad,
inherit bad allele from Mom, good from Dad,
inherit good allele from Mom, bad from Dad,
inherit bad allele from Mom, bad from Dad.
We know that the last is not the case for the brother.  The first 3 are still equally likely.  And in 2/3, brother is a carrier.

Let me elaborate on swbarnes2’s answer.
The “Possibility of Jane's brother being a carrier” is indeed the trickiest part of the overall question. I have seen that even some teachers of genetics were puzzled when seeing the correct answer (2/3).
It is true that before the brother is born the probability of he being Cc is given by the standard Mendelian rule, which states, for a Cc x Cc mating, ¼ of the offspring will be CC, ¼ cc, and ½ Cc.
But that answer ignores the fact that the brother is already born and (presumably) has an age by which all cc homozygotes have been recognized. Then, we know that he is not cc and can only be CC or Cc, whose probabilities sum up to ¾. It follows that he is Cc with probability ½ / ¾ = 2/3.
This kind of problems are generally tackled by using the Bayes theorem, which is a way to transform a prior probability into a posterior probability. In this case, we know that the prior probability, Pr(Cc), of the brother being a carrier is 50%, and want to calculate the posterior probability, Pr(Cc | not-cc), which is the probability that he is a carrier given that he is not affected. The Bayesian rule has the general form
Pr(A|B) = Pr (B|A) x Pr(A)/P(B),
which in our case reads
Pr(Cc|not-cc) = Pr(not-cc|Cc) x Pr(Cc)/Pr(not-cc).
As the first factor in this equation equals 1 (it is certain that a subject is not cc if he is Cc), it easy to see that the solution corresponds to the above, perhaps more intuitive, calculation. In more complex situations (consider for example if Jane's brother is young, and a certain proportion of cc subjects are diagnosed only late in life) the Bayes rule is useful, as it help decomposing the problem.


text:
There are some species that grow throughout their lives -- is there evidence that even in adulthood their brains increase in size?
One species I have read about is carp whose growth is limited only by food supply and space. One can actually, because their skin is almost transparent, see their brains and it sure does look like larger carp indeed have proportionately large brains. If this is so, are their behavioral consequences and do such carp recover from brain injury?

Please note that I've focused on the question in your title. It is best to have only one question per post since that makes it easier for other users to find material. It also helps you get more complete answers. Please post your follow-up questions  separately.

Your question falls into an area of study known as allometry.
It is generally believed that brain size must increase as body size increases1,2. This relationship has been demonstrated  in fish 3,4, including carp. This phenomenon is also seen in other (non-mammalian) vertebrates including the Nile Crocodile (Crocodylus niloticus)5.
This continued growth is correlated with the ability to regenerate after brain injury2.
References:

Jerison, H. (2012). Evolution of the brain and intelligence. Elsevier.

Kaslin, J., Ganz, J., & Brand, M. (2008). Proliferation, neurogenesis and regeneration in the non-mammalian vertebrate brain. Philosophical Transactions of the Royal Society B: Biological Sciences, 363(1489), 101-122.

Bauchot, R., Diagne, M., & Ribet, J. M. (1979). Post-hatching growth and allometry of the teleost brain. Journal fur Hirnforschung, 20(1), 29-34.

Brandstätter, R., & Kotrschal, K. (1990). Brain growth patterns in four European cyprinid fish species (Cyprinidae, Teleostei): roach (Rutilus rutilus), bream (Abramis brama), common carp (Cyprinus carpio) and sabre carp (Pelecus cultratus). Brain, behavior and evolution, 35(4), 195-211.

Ngwenya, A., Patzke, N., Spocter, M. A., Kruger, J. L., Dell, L. A., Chawana, R., ... & Manger, P. R. (2013). The continuously growing central nervous system of the Nile crocodile (Crocodylus niloticus). The Anatomical Record, 296(10), 1489-1500.


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What is this Kenyan insect?

This insect was seen in Nairobi, Kenya. Underside is striped black and white. What is it?

Welcome to Biology.SE! Identifications questions should be tagged as such and also include an estimate of the size of the organism and as much habitat information as possible. Please [edit] your post to include this information as it may be essential for a proper identification. ——— Please also take the [tour] and then go through the help pages starting with [Ask] questions effectively on this site. Thanks!

Perhaps a bug (Hemiptera) that is mimicing the cotton stainer bug. Might be an assassin bug.


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Kansas Spider Identification, found in Pasta Package
I live in Kansas. I found a spider inside my macaroni pasta package after dinner (6pm), and I really want to figure out its species.
Since I have consumed food from that package, I'm especially concerned if itself or its eggs and/or whatnot could be poisonous to human. I think the spider didn't bite me, unless it has painless and asymptomatic bites.
The spider is brownish in its color, and approximately as large as a penny (~2 cm diameter). I have taken pictures of the spider (currently alive, in the sink) attached below. I really appreciate your help!!

It is a crab spider, likely of genus Xysticus but possibly genus Ozyptila. If you needed to get down to genus, bugguide (https://bugguide.net/node/view/63082) says that we can differentiate these genera by counting the macrosetae (the thick hairs) on the front legs. You would need some high-quality zoomed photos to check those.
In general, eating spiders is not toxic for people or animals. Many animals (birds, fish, cats, etc) eat spiders without having the spider venom affect them in any detrimental way. The venom in crab spiders is not much different from the majority of other spider families in North America. (Black widow and Brown recluse venom are exceptions when it comes to bites from the spider, and I don't know how bad it is to eat those... but these crab spiders are not related to those dangerous ones).

Venoms (basically by definition) need to enter the body through a wound to be effective, as they involve larger compounds that can't be absorbed through the skin or digestive tract. As long as your digestive tract is free from ulcers, there shouldn't be any danger to swallowing something venomous.

Thank you so much for the information!


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Identifying unknown biting insect
Pattaya (Thailand). Unknown insect (similar to a beetle) that bite: long 2 mm, large 1 mm. It has 2 front claws. Pictures attached.

Probably it lost some legs when killed (I felt the bite and I instinctively crushed it).

That looks like the head of an ant. Without better photographs and the rest of the body, it will likely be unidentifiable.

Hello, it is not the head, is the whole body. I will look for a better camera to take a proper picture and post it here.

@acvill you right, I took a proper picture... 90% is just the head of an ant!


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How did fish evolve the ability to breathe on land?
Doesn't make sense. It would be like a human evolving the ability to breathe on the moon without a spacesuit.
How would the organism be able to carry out such an evolutionary adaptation, when the evolution of it involves death to the organism, preventing it from ever being able to evolve it to begin with, because the variation cannot develop, or be passed along to the population due to it needing to be functional to survive at all.
Also, how does an organism gain the new information necessary to get those land breathing or moon breathing adaptions, from a genome that doesn't already have such an ability encoded in its genetic morphology in the first place?

Evolution doesnt happen suddenly.. Sudden changes in environment have caused mass extinctions several times in the earth's evolutionary history.
BTW, amphibians came before completely terrestrial animals.
You can edit the question to make it a more focused: e.g. ask about evolution of lungs.

Note: Reptiles and Amphibians are sister groups encompassed in the clade of Tetrapoda. See tolweb.org.

This assumes that it's either underwater breathing or air breathing.  The two could exist together in the same organism (and almost certainly did). The very first version would allow a "fish" to spend short amounts of time out of the water (I.e. be very inefficient). This would be a step up from a fish having to "hold its breath" out of the water.

Just out of interest, are you prepared in any circumstances to mark an answer correct? If not, then this is not a question according to the rules of SE and you should delete it. I will assume that failure to reply indicates an answer no. Please note this is a question and answer site, not a discussion site.

It would be like a human evolving the ability to breathe on the moon without a spacesuit.... strangely enough, the only thing preventing humans from just wearing a face mask and walking around in space is our skin is too flexible. It need a source of inward pressure..denser collagen.... or really super strong spandex clothes..a skin suit as it is called.. Human skin is already air tight enough that we do not need the skin suit to be air tight.

Air-filled, gut-tube-derived organs (i.e., air bladders, gas bladders, and lungs) have a very wide distribution among fish in general, so the most parsimonious explanation is that the first terrestrial tetrapods already had a lung-like structure.
The image below (from Kardong's Vertebrates) shows two major clades of fishes, Actinopterygii (ray-finned fishes) and Sarcopyerygii ("fleshy-finned" fishes, which include both lungfish and tetrapods). Given the wide distribution, a homologous organ was almost certainly present at the most recent common ancestor of these two groups. I don't know what the evidence is for lungs further down the tree, so I'm not certain about loss of lungs in Chondrichthyes (sharks, rays, skates).

You ask two question. it is always better to restrict a post to only one accurate and narrowed enough question. I will not provide a full review of how did the origin of tetrapods occur. I just give some critics on you question give some words about the evolution of lungs, discuss your comparison with "breathing on the moon" and answer your question concerning the origin of genetic variation.

How did fish evolve the ability to breathe on land?

This question is way too broad, you should narrow it down. You say that this evolution is impossible but you should provide some argument so that we can discuss them. For the moment there is not much to discuss about. The only thing one could si to review tons of article concerning the evolution of tetrapods. I bet you're interested in the evolution of lungs during at the origin of the lineage of the tetrapods. If so… In short, swim bladder and lungs are homologous organs. According to this that at the time tetrapods-like animals evolved, this organs was used to gulp air in oxygen-poor environment. This organs then evolved into various forms of lungs as we know them today in terrestrial and none terrestrial vertebrates. This organ also further evolved in order to control the buoyancy. Note: Several popular sources gives different informations. One would need to go into some articles in order to make sure of details such as "were this organ already used to control buoyancy before the speciation of the tetrapods?".
Here is a simple source that you may like
You say that evolving abilities to breath in the atmosphere for tetrapods is like evolving abilities to breath on the moon in humans. Well there are several differences that should be considered that make the moon really not a pleasant place to live! The temperature for example spans between 100K and 373K according to this wiki! But let's forget about these other ecological factors. One big difference is that humans do not live in an environment that offers a gradient from earth atmosphere to moon atmosphere while first tetrapods-like animals lived in such a gradient. Also, when you talk about human, it feels like you consider the wrong time-scale. It probably took quite a lot of time to evolve from fish-like to totally terrestrial tetrapods.
You might want to have a look to this interesting post. Life apparently independently emerged out of water at least 9 times.

"How does an organism gain the new information necessary to get those land breathing or moon breathing adaptions, from a genome that doesn't already have such an ability encoded in its genetic morphology in the first place?"

If I understand your point correctly one could rephrase your question into:

"I understand the process of Natural Selection (NS). It selects for some already existing variants but what process creates the variation from which NS makes its selection?

And the answer is: Mutations. In the narrow sense (in order to keep it easy), a mutation is a change in a genetic sequence. Such change typically occur during the meiosis, process that occurs in all sexual reproductions but it also occur during any mitosis (standard cell division) or other phases of the cell cycle.
In short, mutations create genetic variations and differential reproductive abilities between individuals in a population results in a selection (called Natural Selection) for variants that are the best at reproducing.

According to the WP entry on amphibious fish (http://en.wikipedia.org/wiki/Amphibious_fish) the swim bladder evolved from a lung-like organ, and in tetrapods this was the basis of air breathing. There are modern lungfish too (http://en.wikipedia.org/wiki/Lungfish).

@AlanBoyd Indeed it seems there is a contradiction between wiki and Berkeley's website! There are quite a lot of literature on the subjet but I don't feel going through it for the moment (and not for this post!). Here is a review that might be of interest. I updated my answer.


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Can nature create codes and specified complexity?
Is there an example of nature creating codes or specified complexity? It is said by Creationists that codes can only come from minds, and since DNA has a code, it was created by a mind.
Is this true? If false, can you explain how unguided, unintelligent nature could create coded specified information? Just as a note to show where I'm coming from, I am an Evolutionist.
But I have to admit, this appears to be a very, very strong argument in favor of special creation by an intelligence.

The problem here is: How do you define nature? At what step is something "Natural" as opposed to "Divine"? Is there a difference the further down you go?

Simple answer: Creationism is belief, not science. So they claim things, but not set up a hypothesis which can be falsified or proven (which is the way science is doing this kind of thing). And by the way: Why can't nature develop codes? DNA, proteins and many more examples proof that its happening.

I do not have time to write a proper answer right now, but "codes can only come from minds" seems like an inaccurate and arbitrary statement - which makes it unscientific. For example, how should we define a mind? And what sort of evidence would support or contradict this statement?

Add references to your question. Statements like; "It is said by Creationists that codes can only come from minds..." are far from obvious and you need to back them up with a logical argument or a source making such an argument. As it stands, the question is just an empty statement that includes poorly defined terms (mind, specified complexity).

I'll vote for closing your question unless it is made scientific. I really don't see any reason why "a code can only comes from mind". If you can provide any scientific argument in this sense, then we'll be able to discuss the question. Note: you'll need to define what you mean by "mind"

@LotusBiology I recommend that you take some time and have a look at Understanding Evolution by UC Berkeley. It is fast and very introductory and you will learn a lot faster. Enjoy!

If you think of laws of nature as being codes, then we've found many instances of such codes that are in some sense not man-made. Of course, you could say that they are of "divine creation" or some such thing, but then you'll probably be ready to label everything seemingly intelligent, interesting or found as such. So let's not go there! These laws can be seen as codes, albeit not intentionally created ones.


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Can you answer Ray Comfort's question on Biological Evolution?
https://www.youtube.com/watch?v=U0u3-2CGOMQ
There's this video on Youtube about biological Evolution that has gone viral. I'll paste it above for your convenience.
To cut to the chase, Ray Comfort asks this question repeatedly to various people, and I guess he never got an answer or a good answer. The question is:
Can you think of any observable evidence for Darwinian Evolution where there is a change of kind?
By change of kind, I assume Comfort wants observable evidence of one species/kind morphing into a new or different kind/species.
How would you answer this challenge?

clearly he doesn't understand the process of evolution.

A process that takes millions of years can't be directly observed. However, there have been several observed speciation events in lab experiments including in Drosophila (fruit fly) species. IIRC, There is also evidence of early-stage speciation in events in Anoles and a species of Australian lizard whose names elude me at the moment.

evidence of speciation doesn't necessarily have to be observed "live" to be good evidence of speciation. (I say speciation because evolution is not "one species/kind morphing into a new or different kind/species.") You can look to the most recent common ancestor between humans and chimpanzees - http://en.wikipedia.org/wiki/Chimpanzee%E2%80%93human_last_common_ancestor - candidates are  Ardipithecus kadabba, Sahelanthropus tchadensis, and Orrorin tugenensis.

I wonder if Ray Comfort has any "observable evidence" for theological assumptions, and if he really understand a fraction of the evidences of evolution.

@GRIFFINEVO If Evolution is not one species/kind morphing into a new or different species/kind, then where do all the different kinds come from? The only other option would be special creation would it not. See that's what Comfort is aiming at. If Evolution cannot get these new kinds to come from its mechanisms, then God must have been the one to do so. He's asking for vertical evolution, as Creationists accept horizontal evolution(microevolution). So GRIFFINEVO, how does Evolution account for new kinds, rather than just change within kinds?

The definition of evolution does not stipulate the manifestation of new species, it is only "descent with modification" - a change in traits along a lineage over time. The evolution of new species is called speciation. Check your definitions, that is all.

@LotusBiology There is no such thing as "vertical" and "horizontal" evolution, as separate processes. The movie is just a tendentious piece of propaganda, and every attempt of an honest answer is being cut-off or misrepresented.

Also, to a lesser or greater extent, the species concept is only a useful abstraction. In many, many groups of organisms, species are fluid and ill-defined. Even in tetrapods, where species are more-or-less well-defined, it's often unclear where the boundaries between species are.

This question appears to be off-topic because it is about Creationism.

As a virologist, this is trivially answered.  I see adaptive mutations that alter phenotypes arising and taking over populations over periods of a few days. Q.E.D.

Comfort is always there for a good laugh. My personal favorite was when he used a banana (which ironically evolved to its current state by humans unnaturally selecting it) to prove God had created everything XD What's amazing is that there are people who actually believe him lol. Anyway, thought I'd leave some links to some speciation literature here:
http://www.talkorigins.org/faqs/faq-speciation.html, http://www.talkorigins.org/faqs/speciation.html, http://www.pnas.org/content/102/suppl_1/6550.full.

The question is really not well defined for two reasons:

What would you accept to consider being an observation? It seems to me that many creationist would accept to consider something to be an observation only if it is extremely simple to understand it. The methodology of observation in evolutionary biology (just like in most science field) are not always very simple to understand for non biologists.
The word "kind" is not define in the sentence "what is a change of kind?".

Because the question is poorly defined, it makes it impossible to answer. And that is the common problem with creationist arguments. Their arguments are not scientific and therefore cannot really been argued for or against. Just want to say also that evolutionary biologist do not need non-scientist to fight against their work. Scientists create their own criticism. Scientists do not form a political party that fight for one point of view just for the purpose of defending it. They think neutrally and objectively (as much as a human can).
Change of kind
If change of kind = change in DNA sequence
Let's assume change of kind means change in the DNA sequence. Change of kinds have been observed in real time in almost all lineages we looked at (including humans). These changes are not only observable at the genetic level but also at the so-called phenotypic (loosely speaking the phenotype is way the organism looks like) level. We can for example think of disease in humans that are due to de novo mutations.
If change of kind = a population/species adapt to a new environment
If by change of kind, one mean "adaptation", then adaptation to new environment have been observed in tons of lineages again. In a lab it can be observed in bacteria within the course of a month. It has been observed in many mammals, birds, plants and unicellular eukaryotes.
If change of kind = one lineage splits and there is reproductive isolation
If by change of kind, one mean "reproductive isolation", then reproductive isolation has also been observed in real time and many times in nature and in labs (see this post for example)
If change of kind = something else
Just tell me what is this something else and we'll let you know if it has ever been observed. We can also let you know if this something is a prediction from the theory of evolution or not.
Observation
If you accept observation based on slightly more complex method such as molecular clocks and comparative genomics, then you'll find thousands of example of "change of kind", again in roughly speaking all lineages of the tree of life.
Very recently I worked on the speciation of clownfishes. This speciation was dated and we observed morphological and genetic adaptation to specific environments.
P.s. I haven't looked at the video completely but only some randomly selected part for a total duration of about 30 seconds! At first sight I'd like to say: Please don't fall into the trap of the media. One making interviews of people that are sometimes identified and sometimes not and that select for some part of their answer and that ask poorly defined question can really easily say anything from his records.
I welcome editing and I welcome anybody wanting to add references. One can find tons of them!

+1 for the second to last paragraph. I find it impossible to believe that P.Z.Myers, who makes his living partly by debunking creationists, would be unable to answer the question as posed.

I don't know why we haven't labeled domestic dogs as different species. I know they are still technically capable of interbreeding, but in the wild I doubt chihuahuas and great danes are going to interbreed very well. All we have to do is define dogs as different species and we can point to that everytime the creationists ask for an example of a new species.

It depends a lot on the meaning of "Kind."  An ill-defined term is subject to goal-post-moving, so that if an example is presented of A splitting from B, or A descending from B, the person asking the question can claim that A and B are still the same "Kind".  With a sufficiently broad definition of "Kind", you are just a funny kind of fish.
It can also be used as a strawman, to ask for evidence of a sort of evolution that nobody accepts, for example, the crocoduck.
Secondly, @rg255 is absolutely correct that observable evidence does not have to be "live."  Archaeologists for example can and do observe evidence of battles without ever being in combat.  For a partial list of evidence for speciation and the common descent of different species from a common ancestor, see http://www.talkorigins.org/faqs/comdesc/.

So how does "vertical evolution" work Kevin? Tell me if this is wrong: So -common ancestor- population has a portion of it split off and go into a new environment, and another portion go somewhere else, and those two populations, if given enough time and environmental pressure, morph into a completely new kind? If so, why don't we see bacteria morph into something other than bacteria if they are put into a new environment? Given their quick reproduction?

@lotusbiology To go from a bacteria to something else, such as a simple multi celled organism, is a monumentally large step to try and observe.

@LotusBiology Because evolving from single cell to multi-cellular organisms is not a small but a huge step. It took quite a while (about 2 billions years after the first unicellular organisms occured). And: Evolution is taking place in bacteria, there is a nice experiment about it. See here.


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Newts in a rodent larder. Limits of regeneration? (NSFSqueamish)
Observation.
In the Surrey woodland of southern UK mainland I chanced upon a piece of corrugated metal. Lifting it up I found a bare patch of soil except for what appeared to be a nest of dry plant material and two palmate newts.
The newts had suffered traumatic removal of most of their heads leaving just the back-most portion of the skull and a dry wound with an airway/oesophagus present, little or no sign of a lower jaw or orbital sockets was present.
The newts showed rudimentary reflex withdrawal from gentle prodding, confirming that basic life-functions continued.
Supposition.
This was a rodent's nest and larder (food-store), the newts being preserved (and immobilised) in this way for later consumption.
Question.
Assuming sufficient body-mass and internal resources to draw from (and not being interrupted by being eaten), might these newts be able to regenerate to become fully functional again? (The question of resource limits within a newt might be mooted, but not the primary focus of my question).
Research.
Sciencedirect:

perfect adult regeneration of many other important tissues and
structures as diverse as heart, brain, spinal cord, jaws, retina and
lens, has also been described

Daniel Berg:

Experiments have been done on newts, in which a 70% of the optic
tectum is surgically removed. A  proliferative response was observed
in these animals and after 8 months the tectum was  almost  fully
regenerated,  but  the  origin  of  the  new  neurons  was  not
investigated  (Okamoto et al., 2007).

Here, it's later indicated that the origin of the progenitor cells for the regeneration is not known.
I'm unable to find or access any more recent or advanced research

Have no fear for the newts, they'll get better.


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How big does a landmass have to be in order for biota to not undergo island dwarfism or gigantism?
Somebody asked it here, and the answer was basically "there's no specific size". Still, I'd like to ask if there's an average size to it. Would a Greenland-sized landmass cause elephants to evolve into smaller sizes? (On a side note, were there mammoths in Greenland?)

Please don't add extraneous material to your posts, instead if you have questions about site etiquette please use the [meta] site. However, if you are posting using two separate accounts, you may find this information on merging accounts to be of interest.

I don't know the answer properly, so I welcome other input.
You can probably work this out more or less empirically. Going through the (possibly incomplete??) lists of island gigantics and insular dwarfs you can see a list of which islands they have been found on. Also ignoring the dinosaurs, as we don't properly know the size of islands in those cases
The largest listed is Madagascar and it's about 1/4 (actually 0.275) the size of Greenland at about 587,041 km2 / 226,658 mi2 . It may be that this is about the limit.
Note that this answer relies entirely on the current sizes of the islands, it does NOT take into account previous changes in land area from such things as sea levels raising/lowering. I am almost certain that there will be more to it.

Thanks, but Borneo is larger than Madagascar and its native subspecies of Asian elephant is slightly smaller than the others.

@LordNobody - It wasn't on the list of animals with dwarfism on Wikipedia hence my "(possibly incomplete??)" phrase.

Okay, sorry to miss that.


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Are 99% of animals bilaterally symmetric?
The Wikipedia article for "Symmetry in Biology" claims: "Animals with bilateral symmetry are classified into a large group called the Bilateria which contains 99% of all animals (comprising over 32 phyla and 1 million described species)."
This claim that almost all animals are Bilateria can be found in other sources too, e.g. in "A new paradigm for animal symmetry" by Gábor Holló. In both cases, however, no source is provided. I'm no biologist so I don't no exactly how self-evident this claim is.
Does someone know a source corroborating these claims?

See: https://en.wikipedia.org/wiki/List_of_animals_featuring_external_asymmetry?wprov=sfla1

Well, you could count yourself.
Kingdom Animalia encompasses about 1.3 million known species. There is one large phylum where most species lack symmetry - Porifera (5,500 species). Cnidaria (10,000 species) have radial symmetry.
All the other broad phyla, from flatworms to chordates, have bilateral symmetry during embryonic development. Echinoderms (7,000 species) are pentaradially symmetrical as adults but bilateral as larvae and considered part of Bilateria.
Source:
Campbell biology (specifically, chapters 32 and 33)/ Lisa A. Urry, Michael L. Cain, Steven A. Wasserman, Peter V. Minorsky, Rebecca B. Orr, Neil A. Campbell. -- Twelfth edition. | New York, NY : Pearson, 2020.

Strictly speaking, the Bilateria classification refers to animals with bilateral symmetry during embryonic development. Despite the lack of obvious bilateral symmetry in more developed specimens, Echinoderms are part of the Bilateria group.


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Anybody know what kind of bug/cricket this thing is? I can't narrow it down enough
Spotted just walking about down the road.

Welcome to the site, please take a [tour] and visit the [help] to learn what makes a good question to be asked here. Specifically for identification purposes we need good quality photos, preferably from several angles, a location (general, district/county level would be good), and an approximate size.

Grasshopper, immature, I do not know the specific species.

Location is the U.S. I have a video but the site would not let me post it.

Please [edit] your post to include all the requested information (hover over or click on the species-identification tag for details) — comments are ephemeral and often overlooked so they should not be used to convey important information. In addition, as mentioned by @bob1 we need a location much more specific than "U.S." — as a random example, the fauna of central Texas and costal Maine are very different! I believe there are services that will convert (portions of) a video into a GIF that can be included — you may also include a link to the full video.

@ErgoNot try using a site like ezgif.com to convert your video to a gif (which can be uploaded into your post. Just make sure you optimize it to be <2mb for the system to allow it to be included in your post.

It could be a immature lubber grasshopper ( adults look rather different).


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bird that might be a young one that didn't fledge happily
Can anyone identify this bird - located in Massachusetts

Welcome to Biology.SE. For identification questions please include an estimate of the size, what part of Massachusetts, and include any behavioral, habitat (e.g. types of plants), or other details that you noticed. In addition, if possible clearer pictures from multiple angles would be very helpful. Please [edit] your post to include as much of that information as possible. Also, what do you mean by "didn't fledge happily"? ——— Please also take the [tour] and go through the [help] starting with [ask] questions effectively on this site. Thanks.

It is difficult to be sure without clearer pictures, but my best guess would be a female (and/or immature) Brown-headed cowbird.
This is based on the heavy conical beak, my guess at the size, the overall grey-brown coloration, dark eye, dark beak, dark legs, and the faint suggestion of a line behind the eye. In addition, this is a common species in many parts of Massachusetts.
If you have seen these cowbirds (the males are quite distinctive) in your area that would support this idea.

Public domain image from USGS.

Cowbirds do not raise their own young, they lay their eggs in other birds nests . The cowbird young are generally larger then and push out the original young. It could be the adoptive parents have abandoned this one as it seems big enough to be on its own .

Yes, does that have something to do with my answer?

Looks like a young Cowbird to me, for the same reasons that tyersome gave.  Young Cowbirds, like young Starlings, are pretty bland and unmarked.  The short neck and big round head also point in that direction.

Another similarity that could be added to your reasoning is the culmen/dorsal ridge of the upper mandible (The upper prong of the mandible is embedded into the forehead) that looks quite similar when enlarging the OP's picture.