text:
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It's been awhile since I've had a hardware question, but can anyone make any recommendations on nice monitor speakers around $100? What I'd like to do is have my current ipod dock in the center connected to my CI's stereo headphone jack and the two monitor speakers on either side each connected to my mono line outs. I've checked out the M Audio AV 30's and the Samson MediaOne 3A's-are these good speakers?
Now I'm looking at the connections, and I need this to connect to my CI's mono line outs. I don't understand alot about speakers and stuff, since I've never really owned any, aside from my Sony ipod dock. Therefore I'm not sure if all monitor speakers can make that connection. I cant tell much from the images of the ones I've viewed online.
Are the speakers I mentioned above good for this price range or are there better options?

subset: commoncrawl


text:
This book from Professor Sir Michael Marmot (knighted for his services to epidemiology and understanding health inequalities) is concerned with a very simple question: why do people of higher status have better health and live longer than those of lower status?
Have you ever wondered how high a flea of the size of a human could jump, why rivers meander or how high a tree can grow? Mathematics in Nature provides answers to all these questions and many more, while introducing the reader to the ideas and methods of mathematical modelling.
In our day-to-day lives we all use, and are in fact dependent on, physics. For example, all of modern (and not so modern!) technology relies on our knowledge of underlying physical principles. However, physics is also one of the most commonly feared sciences, with many people put off by the complex details which have developed alongside the subject's sophistication.
Although this book is 50 years old this year, its wisdom is needed now more than ever, as increasing computer power and our headline-obsessed media look set to drown us all in a sea of "statisticulation". This is the word coined by Darrell Huff to describe misinformation by the use of statistical material. Biased samples, dubious graphs, semi-attached figures: he describes all the usual suspects clearly and simply, rounding off with the most useful topic of all: How to Talk Back to a Statistic.
"Economic theory predicts that you are not enjoying this book as much as you thought you would", remarks Steven E. Landsburg at the start of one of the most enjoyable chapters of The Armchair Economist. The point turns out to be this: the fact that you have chosen to read it is a sign that you have probably overvalued it in relation to all the other books you could have read instead.
I have never before read a book that has so frequently made me think "wow, that's interesting!". "Mathematics for the Imagination" is an absolutely fascinating account of mathematical methods and discoveries and the people behind them, with the sordid histories of mathematicians through the ages jostling for the reader's attention next to their elegantly simple proofs.


text:
COMP Cams#249-4512-16Hi-Tech Race Rocker Stud |
Comp Cams takes pride in having the finest rocker arm studs available on the market. The High Energy and Magnum series studs work well in applications with moderate lifts and spring pressures and are available in the popular 3/8" and 7/16" sizes. When ultimate strength is required as with high rpm roller cam applications, the Hi-Tech Race Stud is the answer. This stud has a thin jam nut for rocker clearance, rolled threads for maximum contact and a ground-flat top so accurate valve adjustment can be achieved and maintained. The diameter of the jam nut is larger in order to spread the load over a larger area. All Comp Cams studs have generous radii and a black oxide finish.


text: 99 min | R Director Luc Besson (TAKEN 2), known for some of the most memorable and tough female action heroes on screen, delivers another female action-thriller starring Scarlett Johansson and Academy Award winner Morgan Freeman. This action packed flick follows a woman living in a world run by the mob, street gangs, drug addicts and corrupt cops. Accidentally caught in a dark drug deal, Lucy turns the tables on her captors and transforms into a merciless warrior evolved beyond human logic.


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text:
Roboworm Fat Straight Tail Worms 8pk - $3.49 to $3.59
The Roboworm Fat Straight Tail Worm brings you the classic soft plastic worm shape with the clean colors and hand-poured quality you are used to getting from Roboworm - the Country's premier plastic worm company. The Fat Straight Tail worm offers a thicker head section so your hook will hold more securely when Texas-rigged and will resist tearing better when the fish are biting. Roboworm's exclusive Salt Release System comes with every Fat Worm. It gives bass a burst of salty flavor when they bite, making them hang on longer - for a better catch ratio. If you've been discouraged trying to Texas-rig the standard Roboworm Straight Tail Worm, choose your favorite color and get the job done with the Roboworm Fat Straight Tail Worm!
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4.5" | 8 |
6" | 8 |
34 Available Colors Sign up for Roboworm Worms news and updates.
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9 colors available
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Customer Reviews Back to Top
Comments: These worms have become one of my go-to baits. I have fished them Texas rigged, weightless, wacky, and shakey and they have out fished other plastics in my bag. The fat and original are both great baits. Get a pack, you won't be disappointed.
From: Dale: OH 5/14/14
Comments: These are my favorite Drop-Shot worms in the world. I use these over the regular straight-tail because they have the same action, and a more natural profile. When vertical fishing, I don't even move my rod tip. I just feather the line to get a natural "popping" motion from it. For a more aggressive approach, you can bob the rod tip about 1/2" to make the tail "swim". By the way, these aren't as fragile as people say. I've caught well over 20 fish on the same worm. If you thread the bait on a #2 Drop-Shot hook instead of nose-hooking it, the durability will go through the roof. The best color will change by the hour, but my favorites are Aaron's Magic, Red Crawler, Bold Bluegill, Sxy Shad, and Prism Shad. Some of the natural colors like Aaron's Magic and Red Crawler don't show up well on beds, so when I sight fish, I stick with Bold Bluegill and Sxy Shad. Keep in mind though, once you open a pack, they might dry out, so keep zip-lock bags handy.
Comments: Great dropshot worm. It seems that the old ones were better though, they had better action and the floated. The new formula this past couple of years now sinks.
From: Paul: Chula Vista, CA
Comments: My #1 dropshot bait brand as well as shakyhead..soft soft plastic that holds up really well.. my grandfather sent me out alot of bass fishing plastics and robos were in there.. still the awesome soft plastic that was used 20+ years ago..
From: Russell: Acworth, GA
Comments: great shaky head worm. works just as good as the zoom trick worm. i like it because it is a little shorter but still has a lot of wiggle
From: Tyler: Cincinnati
Comments: when fishing is tough and you need your limit, go to Robo!!! No picture can do the colors in these worms justice.
From: Andy: Fremont, IN
Comments: The bold bluegill (my favorite color) in the fat version is not the same color as the skinny straigth. The brown on the top brown color is not translucent but solid. And, the warmouth had more white than the picture showed. Still my favorite worm brand.
From: Pao: Fresno, CA
Comments: Best Shakey Head Worm on the planet-
***Note: If you have questions about this product or need assistance with an order please email your questions to email@example.com


text:
Published: Friday, February 8, 2013, 4:44 p.m.
Live blog: 3A and 4A hoops semifinal games
We'll be live blogging from both 4A boys and 3A girls semifinal games plus the Archbishop Murphy vs. Sehome boys game and Kamiak vs. Lake Stevens boys game. Follow along below.
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text:
The purpose of screening is early diagnosis and treatment. Screening tests are usually administered to people without current symptoms, but who may be at high risk for certain diseases or conditions
Skin Self-exam —A visual check of your skin from head to toe. Tips for performing a skin self-exam include:
- Use a full-length mirror or hand-held mirror to check hard to spot places, such as between the buttocks or in the genital area.
- Do the exam in a well-lit room.
- Turn from front to back and left to right.
- Note the size, shape, color, and texture of all skin blemishes and moles.
- Check your fingernails, palms, and forearms.
- Check your feet, toenails, soles, and between the toes.
- Examine your scalp, separating the hair with a comb or a blow dryer.
Skin Exam by a Physician —If you have any increased risk for developing melanoma, an annual skin examination by a dermatologist may be appropriate. Your ophthalmologist or optometrist should also check the back of your eyes for possible melanomas as part of your routine examination.
The National Cancer Institute and American Cancer Society recommend that you perform monthly skin self-exams, especially if you have many moles. If you notice any changes, contact your healthcare provider.
Revision Information
- Reviewer: Mohei Abouzied, MD, FACP
- Review Date: 03/2015 -
- Update Date: 03/15/2015 -


text:
Everything you need to unleash kids' imaginations
Use your Crayola Color Wonder Airbrush to create unique Valentines for friends and family!
Create a sprightly springtime masterpiece with Crayola® Washable Window Markers. Your favorite flowers can bloom as ofte
Make a cereal-box monster that's wiggly, squiggly fun! Crayola® Color Wonder™ means it's mess free.
A country's flag is a banner of national pride. For Scotland, the simple design of a white cross on a blue background is
Who was St. David, and why is he important to the Welsh? Make a leek and daffodil bouquet to celebrate customs in Wales.
Patterns are everywhere! Capture your favorites inside squares for a surprising quilt-like design using Black Color Expl
Combine stacks of your favorite colors for some eye-popping art.
Caps…Caps for sale! Can you hear the peddler calling? Capture the fun in this whimsical folktale about a peddler, his ca
Open a window on kids' creativity with imitation stained glass. Children boost their brain skills as they visualize, pla
Keep your colored pencils, markers, and other cool stuff organized in this beneath-the-earth storage container.
Sport your team colors. Show your manly style with wristbands that are punched with texture. Best of all, they're fun to
Valentine's don't need to be flat hearts that lay there on the table. Give yours a little more "wow" with bright Crayola
This colorful Japanese holiday weaves together astronomy, language arts, culture, and design. Kids can fly their poetry
Chanukah is one of the most beloved Jewish holidays. Decorate for this 8-day festival of lights with a beautiful wallhan
Make a wish upon a streaking star with Crayola Color Explosion™ paper and color-reveal markers
Bright Crayola Color Wonder™ Paint colors are filled with energy. Make no-mess designs that radiate—all with a simple tw
Add fun to your hair with a cool, star-studded headband. You'll feel SO glamorous!
Constellations have universal appeal! With Starry Names, kids see themselves in their rendition of a starry night sky.
Looking for a unique gift for someone special? This handmade craft is easy to create, colorful, and practical, too!
What is more exciting than your child's very first day of school? Make a starting school treat cone with your child and
Kids make this colorful license "plate" for your next trip. They search for license tags from the U.S. and Canada, or an
How do you stay in touch with friends and family? E-mail? Letters? Phone? Display colorful portraits of people you love
Stick puppets are perfect for some easy, no-strings-attached fun. The curtain is always up for their productions when ki
Brrrr-ing some winter fun indoors! Sculpt a cool snow creature in the warmth of your home! Decorate it with sticks and C


text:
Great white shark
The great white shark, Carcharodon carcharias, also known as the great white, white pointer, white shark, or white death, is a species of large lamniform shark which can be found in the coastal surface waters of all the major oceans. The great white shark is mainly known for its size, with the largest individuals known to have approached or exceeded 6.1 m (20 ft) in length,[3] and 2,268 kg (5,000 lb) in weight.[4] This shark reaches its maturity around 15 years of age and can have a life span of over 30 years.
The great white shark is arguably the world's largest known extant macropredatory fish, and is one of the primary predators of marine mammals. It is also known to prey upon a variety of other marine animals, including fish and seabirds. It is the only known surviving species of its genus Carcharodon, and is ranked first in having the most attacks on humans.[5][6] The IUCN list the great white shark as a vulnerable species,[2] while it is included in Appendix II of CITES.[7]
The bestselling novel Jaws by Peter Benchley and the subsequent blockbuster film by Steven Spielberg depicted the great white shark as a "ferocious man eater". In reality, humans are not the preferred prey of the great white shark.[8]
Taxonomy[edit source | edit]
In 1758, Carolus Linnaeus gave the great white shark its first scientific name, Squalus carcharias. Later, Sir Andrew Smith gave it Carcharodon as its generic name in 1833, and also in 1873. The generic name was identified with Linnaeus' specific name and the current scientific name Carcharodon carcharias, was finalised. Carcharodon comes from the Greek words karcharos, which means sharp or jagged, and odous, which means tooth.[9]
Ancestry and fossil record[edit source | edit]
The great white shark came into existence during the mid-Miocene epoch. The earliest known fossils of the great white shark are about 16 million years old.[1] However, the phylogeny of the great white is still in dispute. The original hypothesis for the great white's origins is that it shares a common ancestor with a prehistoric shark, such as the C. megalodon. Similarities among the physical remains and the extreme size of both the great white and C. megalodon led many scientists to believe these sharks were closely related, and the name Carcharodon megalodon was applied to the latter. However, a new hypothesis proposes that the C. megalodon and the great white are distant relatives (albeit sharing the family Lamnidae). The great white is also more closely related to an ancient mako shark, Isurus hastalis, than to the C. megalodon, a theory that seems to be supported with the discovery of a complete set of jaws with 222 teeth and 45 vertebrae of the extinct transitional species Carcharodon hubbelli in 1988 and published on November 14, 2012.[10] In addition, the new hypothesis assigns C. megalodon to the genus Carcharocles, which also comprises the other megatoothed sharks; Otodus obliquus is the ancient representative of the extinct Carcharocles lineage.[11]
Distribution and habitat[edit source | edit]
Great white sharks live in almost all coastal and offshore waters which have water temperature between 12 and 24 °C (54 and 75 °F), with greater concentrations in the United States (Atlantic Northeast and California), South Africa, Japan, Oceania, Chile, and the Mediterranean.[12] One of the densest known populations is found around Dyer Island, South Africa, where almost all of the shark research is done.
The great white is an epipelagic fish, observed mostly in the presence of rich game, such as fur seals, sea lions, cetaceans, other sharks, and large bony fish species. In the open ocean, it has been recorded at depths as great as 4,000 ft (1,200 m).[13] These findings challenge the traditional notion about the great white as being a coastal species.[13]
According to a recent study, California great whites have migrated to an area between Baja California and Hawaii known as the White Shark Café to spend at least 100 days before migrating back to Baja. On the journey out, they swim slowly and dive down to around 900 m (3,000 ft). After they arrive, they change behavior and do short dives to about 300 m (1,000 ft) for up to ten minutes. Another white shark that was tagged off of the South African coast swam to the southern coast of Australia and back within the year. This refuted traditional theories that white sharks are coastal territorial predators and opens up the possibility of interaction between shark populations that were previously thought to have been discrete. The reasons for their migration and what they do at their destination is still unknown. Possibilities that may support this idea include seasonal feeding or mating.[14] A similar study tracked a great white shark from South Africa swimming to Australia's northwestern coast and back, a journey of 20,000 km (12,000 mi; 11,000 nmi) in under nine months.[15]
Anatomy and appearance[edit source | edit]
The great white shark has a robust, large, conical snout. The upper and lower lobes on the tail fin are approximately the same size which is similar to some mackerel sharks.
A great white displays countershading, by having a white underside and a grey dorsal area (sometimes in a brown or blue shade) that gives an overall mottled appearance. The coloration makes it difficult for prey to spot the shark because it breaks up the shark's outline when seen from the side. From above, the darker shade blends with the sea and from below it exposes a minimal silhouette against the sunlight.
Great white sharks, like many other sharks, have rows of serrated teeth behind the main ones, ready to replace any that break off. When the shark bites, it shakes its head side-to-side, helping the teeth saw off large chunks of flesh.[16]
Size[edit source | edit]
Male great whites reach maturity at 3.5–4.0 m (11–13 ft) long and females at 4.5–5.0 m (15–16 ft) long. Adults on average are 4–5.2 m (13–17.1 ft) long and have a mass of 680–1,100 kg (1,500–2,400 lb). Females are generally larger than males. The great white shark can reach 6.1 m (20 ft) in length and 1,900 kg (4,200 lb)—2,268 kg (5,000 lb) in weight.[4][3] The maximum size is subject to debate because some reports are rough estimations or speculations performed under questionable circumstances.[18] Among living cartilaginous fish, only the basking and whale sharks and the manta ray average larger and heavier. These three species are generally docile in disposition and given to passively filter-feeding on very small organisms.[19]
A number of very large great white shark specimens have been recorded.[20] For decades, many ichthyological works, as well as the Guinness Book of World Records, listed two great white sharks as the largest individuals: In the 1870s, a 10.9 m (36 ft) great white captured in southern Australian waters, near Port Fairy, and a 11.3 m (37 ft) shark trapped in a herring weir in New Brunswick, Canada, in the 1930s. Some researchers question these measurements' reliability, noting they were much larger than any other accurately reported sighting. This New Brunswick shark may have been a misidentified basking shark, as the two have similar body shapes. The question of the Port Fairy shark was settled in the 1970s when J. E. Randall examined the shark's jaws and "found that the Port Fairy shark was of the order of 5 m (17 ft) in length and suggested that a mistake had been made in the original record, in 1870, of the shark's length".[21]
According to J. E. Randall, the largest white shark reliably measured was a 6.0 m (19.7 ft) individual reported from Ledge Point, Western Australia in 1987.[21] Another great white specimen of similar size has been verified by the Canadian Shark Research Center: A female caught by David McKendrick of Alberton, Prince Edward Island, in August 1988 in the Gulf of St. Lawrence off Prince Edward Island. This female great white was 6.1 m (20 ft) long.[3] However, there is a report considered reliable by some experts of a larger great white shark specimen from Cuba in 1945. This specimen was 6.4 m (21 ft) long and had a body mass of about 3,324 kg (7,330 lb).[22][23]
Several great white sharks caught in modern times have been estimated to be more than 7 m (23 ft) long,[24] but these claims have received some criticism.[18][24] However, J. E. Randall believed that great white shark may have exceeded 6.1 m (20 ft) in length.[21] A great white shark was captured near Kangaroo Island in Australia on April 1, 1987. This shark was estimated to be more than 7 m (23 ft) long by Peter Resiley,[21][25] and has been designated as KANGA.[24] Another great white shark was caught in Malta by Alfredo Cutajar on April 16, 1987. This shark was also estimated to be around 7.13 m (23.4 ft) long by John Abela and has been designated as MALTA.[24] However, Cappo drew criticism because he used shark size estimation methods proposed by J. E. Randall to suggest that the KANGA specimen was 5.8–6.4 m (19–21 ft) long.[24] In a similar fashion, I. K. Fergusson also used shark size estimation methods proposed by J. E. Randall to suggest that the MALTA specimen was 5.3–5.7 m (17–19 ft) long.[24] However, photographic evidence suggested that these specimens were larger than the size estimations yielded through Randall's methods.[24] Thus, a team of scientists—H. F. Mollet, G. M. Cailliet, A. P. Klimley, D. A. Ebert, A. D. Testi, and L. J. V. Compagno—reviewed the cases of the KANGA and MALTA specimens in 1996 to resolve the dispute by conducting a comprehensive morphometric analysis of the remains of these sharks and re-examination of photographic evidence in an attempt to validate the original size estimations and their findings were consistent with them. The findings indicated that estimations by P. Resiley and J. Abela are reasonable and could not be ruled out.[24]
One contender in maximum size is the tiger shark, Galeocerdo cuvier. While tiger sharks which are typically both a few feet smaller and have a leaner, less heavy body structure than white sharks, have been confirmed to reach at least 5.5 metres (18 ft) in the length, an unverified specimen was reported to have measured 7.4 metres (24 ft) in length and weighed 3,110 kilograms (6,900 lb).[19][26] Some other macropredatory sharks such as the Greenland shark, Somniosus microcephalus, and the Pacific sleeper shark, Somniosus pacificus, are also reported to rival these sharks in length (but probably weigh a bit less since they more slender in build than a great white) in exceptional cases.[27][28] The question of maximum weight is complicated by the unresolved question of whether or not to include the shark's stomach contents when weighing the shark. With a single bite a great white can take in up to 14 kg (31 lb) of flesh, and can also consume several hundred kilograms of food.
The largest great white recognized by the International Game Fish Association (IGFA) is one caught by Alf Dean in the south Australian waters in 1959, weighing 1,208 kg (2,660 lb).[18] Several larger great whites caught by anglers have since been verified, but were later disallowed from formal recognition by IGFA monitors for rules violations.
Adaptations[edit source | edit]
Great white sharks, like all other sharks, have an extra sense given by the Ampullae of Lorenzini which enables them to detect the electromagnetic field emitted by the movement of living animals. Every time a living creature moves, it generates an electrical field and great whites are so sensitive they can detect half a billionth of a volt. Even heart beats emit a very faint electrical pulse. If it is close enough, the shark can detect even that faint electrical pulse. Most fish have a less-developed but similar sense using their body's lateral line.[29]
To more successfully hunt fast and agile prey such as sea lions, the great white has adapted to maintain a body temperature warmer than the surrounding water. One of these adaptations is a "rete mirabile" (Latin for "wonderful net"). This close web-like structure of veins and arteries, located along each lateral side of the shark, conserves heat by warming the cooler arterial blood with the venous blood that has been warmed by the working muscles. This keeps certain parts of the body (particularly the stomach) at temperatures up to 14 °C (25 °F)[30] above that of the surrounding water, while the heart and gills remain at sea temperature. When conserving energy the core body temperature can drop to match the surroundings. A great white shark's success in raising its core temperature is an example of gigantothermy. Therefore, the great white shark can be considered an endothermic poikilotherm because its body temperature is not constant but is internally regulated.[16] Great whites also rely on the fat and oils stored within their livers for long distance migrations across nutrient-poor areas of the oceans.[31] Studies by Stanford University and the Monterey Bay Aquarium published on July 17, 2013 revealed that In addition to controlling the sharks' buoyancy, the liver of great whites is essential in migration patterns. Sharks that sink faster during drift dives were revealed to use up their internal stores of energy quicker than those which sink in a dive at more leisurely rates. [32]
Bite force[edit source | edit]
A 2007 study from the University of New South Wales in Sydney, Australia, used CT scans of a shark's skull and computer models to measure the shark's maximum bite force. The study reveals the forces and behaviors its skull is adapted to handle and resolves competing theories about its feeding behavior.[33] In 2008, a team of scientists led by Stephen Wroe conducted an experiment to determine the great white shark's jaw power and findings indicated that a specimen more than 6.1 m (20 ft) long could exert a bite force of over 18,000 newtons (4,000 lbf).[23]
Ecology and behavior[edit source | edit]
This shark's behavior and social structure is not well understood. In South Africa, white sharks have a dominance hierarchy depending on the size, sex and squatter's rights: Females dominate males, larger sharks dominate smaller sharks, and residents dominate newcomers. When hunting, great whites tend to separate and resolve conflicts with rituals and displays. White sharks rarely resort to combat although some individuals have been found with bite marks that match those of other white sharks. This suggests that when another shark approaches too closely to another great white, they react with a warning bite. Another possibility is that white sharks bite to show their dominance.
The great white shark is one of only a few sharks known to regularly lift its head above the sea surface to gaze at other objects such as prey. This is known as spy-hopping. This behavior has also been seen in at least one group of blacktip reef sharks, but this might be learned from interaction with humans (it is theorized that the shark may also be able to smell better this way because smell travels through air faster than through water). The white sharks are generally very curious animals, display intelligence and may also turn to socializing if the situation demands it. At Seal Island, white sharks have been observed arriving and departing in stable "clans" of two to six individuals on a yearly basis. Whether clan members are related is unknown but they get along peacefully enough. In fact, the social structure of a clan is probably most aptly compared to that of a wolf pack; in that each member has a clearly established rank and each clan has an alpha leader. When members of different clans meet, they establish social rank nonviolently through any of a fascinating variety of interactions.[34]
Diet[edit source | edit]
Great white sharks are carnivorous and prey upon fish (e.g. tuna, rays,[34] other sharks[34]), cetaceans (i.e., dolphins, porpoises, whales), pinnipeds (e.g. seals, fur seals,[34] and sea lions), sea turtles,[34] sea otters, and seabirds.[35] Great whites have also been known to eat objects that they are unable to digest. Upon approaching a length of nearly 4 metres (13 ft), great white sharks begin to target predominately marine mammals for food.[36] These sharks prefer prey with a high content of energy-rich fat. Shark expert Peter Klimley used a rod-and-reel rig and trolled carcasses of a seal, a pig, and a sheep from his boat in the South Farallons. The sharks attacked all three baits but rejected the sheep carcass.[37]
The great white shark's reputation as a ferocious predator is well-earned, yet they are not (as was once believed) indiscriminate "eating machines". They are ambush hunters, taking prey by surprise from below. Near Seal Island, in South Africa's False Bay, shark attacks most often occur in the morning, within 2 hours after sunrise, when visibility is poor. Their success rate is 55% in the first 2 hours, falling to 40% in late morning after which hunting stops.[34]
Hunting techniques vary by species of the prey. Off Seal Island, the sharks ambush brown fur seals from below at high speeds, hitting the seal mid-body. They go so fast that they can completely leave the water. The peak burst speed of these sharks is largely accepted in the scientific community to be above 40 kilometres per hour (25 mph). However further precision is still speculative.[38] They have also been observed chasing prey after a missed attack. Prey is usually attacked at the surface.[39]
Off California, sharks immobilize northern elephant seals with a large bite to the hindquarters (which is the main source of the seal's mobility) and wait for the seal to bleed to death. This technique is especially used on adult male elephant seals which can be as large or larger than the hunter and are potentially dangerous adversaries. Prey is normally attacked sub-surface. Harbour seals are taken from the surface and dragged down until they stop struggling. They are then eaten near the bottom. California sea lions are ambushed from below and struck mid-body before being dragged and eaten.[40]
Off The East Coast of North America, where white sharks are still poorly understood, individuals have been filmed and documented hunting grey seals. When hunting, atlantic great whites will hunt very close to shore, unlike their counterparts elsewhere which prefer deeper water for ambush and breach attacks. The sharks also utilize sandbars to set up ambushes, and will then chase the seals in a flat-out pursuit. This behavior was revealed to the public media during two episodes of Shark Week, the first being "Jaws Comes Home" and the second being "Return of Jaws". [41][42]
White sharks also attack dolphins and porpoises from above, behind or below to avoid being detected by their echolocation. Targeted species include dusky dolphins,[24] Risso's dolphins,[24] bottlenose dolphins,[24][43] Humpback dolphins,[43] harbour porpoises,[24] and Dall's porpoises.[24] Close encounters between dolphins and predatory sharks often result in evasive responses by the dolphins.[43] However, in rare cases, a group of dolphins may chase a single predatory shark away in an act of defense.[43] White shark predation on other species of small cetacean has also been observed. In August 1989, a 1.8 metres (5.9 ft) juvenile male pygmy sperm whale, Kogia breviceps, stranded in central California with a bite mark on its caudal peduncle from a great white shark.[44] In addition, white sharks also attack and prey upon beaked whales.[24][43]
Even though the great whites are known to generally avoid conflicts with each other, the phenomenon of cannibalism is not alien to this species. Large individuals may aggressively interact intraspecifically with small individuals. A 3 m (9.8 ft) long great white shark was nearly bitten into two by a reportedly 6 m (20 ft) long great white shark in Stradbroke Island, near Brisbane in Australia.[45]
White sharks also scavenge on whale carcasses. In one such documented incident, white sharks were observed scavenging on a whale carcass alongside tiger sharks.[46]
Reproduction[edit source | edit]
Almost nothing is known about reproduction in great whites. Some evidence points to the near-soporific effect of a large feast (such as a whale carcass) possibly inducing mating.[47] Great white sharks also reach sexual maturity at around 15 years of age.[48] Maximum life span is believed to be more than 30 years (see references).
Little is known about the great white shark's behavior in the way of mating habits. Birth has never been observed, but pregnant females have been examined. Great white sharks are ovoviviparous, which means eggs develop and hatch in the uterus and continue to develop until birth.[49] The great white has an 11-month gestation period. The shark pup's powerful jaws begin to develop in the first month. The unborn sharks participate in oophagy, in which they feed on ova produced by the mother. Delivery is in spring and summer.[50] The Northern Pacific population of great whites is suspected to breed off of the Sea of Cortez (as was revealed in the Shark Week episode "Spawn of Jaws"), as evidenced by local fisherman who have said to have caught them and evidenced by teeth found at dump sites for discarded parts from their catches. If the Sea of Cortez is such a breeding ground, it is imperative that the area's laws be better enforced to ensure the survival of the breeding population. [51]
Breaching behaviour[edit source | edit]
A breach is the result of a high speed approach to the surface with the resulting momentum taking the shark partially or completely clear of the water. This is a hunting technique employed by great white sharks whilst hunting seals. This behavior often takes place on cape fur seals at Seal Island in False Bay, South Africa but due to the randomness of the location of a shark's breach, it was very hard to document. It was first photographed by Chris Fallows and Rob Lawrence who developed the technique of towing a slow moving seal decoy to trick the sharks to breach.[52] Here, in the region of 600 natural predatory events are recorded annually from April to September each year. The seals swim on the surface and the great white sharks launch their predatory attack from the deeper water below. They can reach speeds of up to 40 kilometres per hour (25 mph) and can at times launch themselves more than 10 feet (3.0 m) into the air. Data recorded shows that the sharks are successful in just under 50% of all these natural predatory events.[53] In 2011, a 3 metres (9.8 ft) long shark jumped onto a seven-person research vessel off Seal Island in Mossel Bay. The crew were undertaking a population study using sardines as bait, and the incident was judged to be an accident.[54]
Natural threats[edit source | edit]
Although the great white is typically regarded as an apex predator in the wild, it is in rare cases preyed upon by the larger orca (also known as the killer whale). Interspecific competition between the great white shark and the orca is probable in regions where dietary preferences of both species may overlap.[43] An incident was documented on October 4, 1997, in the Farallon Islands off California in the United States. An estimated 4.7–5.3-metre (15–17 ft) female orca immobilized an estimated 3–4-metre (9.8–13 ft) great white shark.[55] The orca held the shark upside down to induce tonic immobility and kept the shark still for fifteen minutes, causing it to suffocate and then proceeded to eat the dead shark's liver.[43][55][56] It is believed that the scent of the slain shark's carcass caused all the great whites in the region to flee, forfeiting an opportunity for a great seasonal feed.[57] Another similar attack apparently occurred there in 2000, but its outcome is not clear.[58] After both attacks, the local population of about 100 great whites vanished.[56][58] Following the 2000 incident, a great white with a satellite tag was found to have immediately submerged to a depth of 500 m (1,600 ft) and swum to Hawaii.[58]
Relationship with humans[edit source | edit]
Shark attacks[edit source | edit]
More than any documented attack, Peter Benchley's best-selling novel Jaws and the subsequent 1975 film adaptation directed by Steven Spielberg provided the great white shark with the image of being a "man eater" in the public mind.[59] While great white sharks have killed humans, they typically do not target them: for example, in the Mediterranean Sea there have been 31 confirmed attacks against humans in the last two centuries, most of which were non-fatal. Many of the incidents seemed to be "test-bites". Great white sharks also test-bite buoys, flotsam, and other unfamiliar objects, and they might grab a human or a surfboard to identify what it is.
Other incidents seem to be cases of mistaken identity, in which a shark ambushes a bather or surfer from below, believing the silhouette is from a seal. Many attacks occur in waters with low visibility or other situations which impair the shark's senses. The species appears to not like the taste of humans, or at least finds the taste unfamiliar. Further research shows that they can tell in one bite whether or not the object is worth attacking. Humans, for the most part, are too bony for their liking. They much prefer a fat, protein-rich seal.[60]
However, some researchers have hypothesized that the reason the proportion of fatalities is low is not because sharks do not like human flesh, but because humans are often able to escape after the first bite. In the 1980s John McCosker, the Chair of Aquatic Biology at California Academy, noted that divers who dove solo and were attacked by great whites were generally at least partially consumed, while divers who followed the buddy system were generally rescued by their buddy. McCosker and Timothy C. Tricas, an author and professor at the University of Hawaii, suggest that a standard pattern for great whites is to make an initial devastating attack and then wait for the prey to weaken before consuming the wounded animal. Humans' ability to move out of reach with the help of others, thus foiling the attack, is unusual for a great white's prey.[61]
Humans are not appropriate prey because the shark's digestion is too slow to cope with a human's high ratio of bone to muscle and fat. Accordingly, in most recorded attacks, great whites broke off contact after the first bite. Fatalities are usually caused by blood loss from the initial bite rather than from critical organ loss or from whole consumption. From 1990 until 2011 there have been a total of 139 unprovoked great white shark attacks, 29 fatal.[62]
A shark conservationist, Jimmy Hall, reported and documented his personal encounter with a very large great white shark, nicknamed Schatzi, in December 2005 in waters off Hawaii. This encounter received worldwide attention as it remained entirely peaceful. J. Hall was at first cautious, but later swam with this shark without cage protection and touched it repeatedly while filming it simultaneously.[63]
A group of great white sharks was believed to be responsible for an attack on a swimmer at Muriwai Beach in Auckland, New Zealand in February 2013, though initial reports placed the blame on a bronze whaler.[64][65] It was the first confirmed shark attack fatality in the country since 1976.[66][67]
Attacks on boats[edit source | edit]
Great white sharks infrequently attack and sometimes even sink boats. Only five of the 108 authenticated unprovoked shark attacks reported from the Pacific Coast during the 20th century involved kayakers.[68] In a few cases they have attacked boats up to 10 metres (33 ft) in length. They have bumped or knocked people overboard, usually attacking the boat from the stern. In one case in 1936, a large shark leapt completely into the South African fishing boat Lucky Jim, knocking a crewman into the sea. Tricas and McCosker's underwater observations suggest that sharks are attracted to boats due to the electrical fields they generate.[69]
Great white sharks in captivity[edit source | edit]
Prior to August 1981, no great white shark in captivity lived longer than 11 days. In August 1981, a white shark survived for 16 days at SeaWorld San Diego before being released.[70] The idea of containing a live great white at SeaWorld Orlando was used in the 1983 film Jaws 3-D.
In 1984, shortly before its opening day, the Monterey Bay Aquarium in Monterey, California, housed its first great white shark which had died after 10 days. In July 2003, Monterey researchers captured a small female and kept it in a large netted pen near Malibu for five days. They had the rare success of getting the shark to feed in captivity before its release.[71] Not until September 2004 was the aquarium able to place a great white on long-term exhibit. A young female, which was caught off the coast of Ventura, was kept in the aquarium's massive 3,800,000-litre (1,000,000 US gal) Outer Bay exhibit for 198 days before she was released in March 2005. She was tracked for 30 days after release.[72] On the evening of August 31, 2006, the aquarium introduced a juvenile male caught outside Santa Monica Bay.[73] His first meal as a captive was a large salmon steak on September 8, 2006, and as of that date, he was estimated to be 1.72 metres (68 in) in length and to weigh approximately 47 kilograms (100 lb). He was released on January 16, 2007, after 137 days in captivity.
In addition, Monterey Bay Aquarium housed a third great white, a juvenile male, for 162 days between August 27, 2007, and February 5, 2008. On arrival, he was 1.4 metres (4 ft 7 in) long and weighed 30.6 kilograms (67 lb). He grew to 1.8 metres (5 ft 11 in) and 64 kilograms (140 lb) before release. A juvenile female came to the Outer Bay Exhibit on August 27, 2008. While she did swim well, the shark fed only one time during her stay and was tagged and released on September 7, 2008. Another juvenile female was captured near Malibu on August 12, 2009, introduced to the Outer Bay exhibit on August 26, 2009, and was successfully released into the wild on November 4, 2009.[74] The Monterey Bay Aquarium recently added a 4.58 feet (1.40 m) long male into their redesigned "Open Sea" exhibit on August 31, 2011. The animal was harvested in the waters off of Malibu.
Probably the most famous captive was a 2.4 metres (7.9 ft) female named Sandy, which in August 1980 became the only great white to be housed at the California Academy of Sciences' Steinhart Aquarium in San Francisco, California. She was released because she would not eat and constantly bumped against the walls.[75]
Shark tourism[edit source | edit]
Cage diving is most common at sites where great whites are frequent including the coast of South Africa, the Neptune Islands in South Australia,[76] and Guadalupe Island in Baja California. Cage diving and swimming with sharks is a focus for a booming tourist industry due to its popularity.[77][78] A common practice is to chum the water with pieces of fish to attract the sharks. These practices may make sharks more accustomed to people in their environment and to associate human activity with food; a potentially dangerous situation. By drawing bait on a wire towards the cage, tour operators lure the shark to the cage, possibly striking it, exacerbating this problem. Other operators draw the bait away from the cage, causing the shark to swim past the divers.
At present, hang baits are illegal off Isla Guadalupe and reputable dive operators do not use them. Operators in South Africa and Australia continue to use hang baits and pinniped decoys.[79]
Companies object to being blamed for shark attacks, pointing out that lightning tends to strike humans more often than sharks bite humans.[80] Their position is that further research needs to be done before banning practices such as chumming, which may alter natural behavior.[81] One compromise is to only use chum in areas where whites actively patrol anyway, well away from human leisure areas. Also, responsible dive operators do not feed sharks. Only sharks that are willing to scavenge follow the chum trail and if they find no food at the end then the shark soon swims off and does not associate chum with a meal. It has been suggested that government licensing strategies may help enforce these suggested advisories.[79]
The shark tourist industry has some financial leverage in conserving this animal. A single set of great white jaws can fetch a one-time price of up to £20,000. However, that is a fraction of the tourism value of a live shark, a more sustainable economic activity. For example, the dive industry in Gansbaai, South Africa, consists of six boat operators with each boat guiding 30 people each day. With fees between £50 to £150 per person, a single live shark that visits each boat can create anywhere between £9,000 and £27,000 of revenue daily.[82]
Conservation status[edit source | edit]
It is unclear how much of a concurrent increase in fishing for great white sharks has caused the decline of great white shark populations from the 1970s to the present. No accurate global population numbers are available, but the great white shark is now considered vulnerable.[2] Sharks taken during the long interval between birth and sexual maturity never reproduce, making population recovery and growth difficult.
The IUCN notes that very little is known about the actual status of the great white shark, but as it appears uncommon compared to other widely distributed species, it is considered vulnerable.[2] It is included in Appendix II of CITES,[7] meaning that international trade in the species requires a permit.[83] As of March 2010, it has also been included in Annex I of the CMS Migratory Sharks MoU, which strives for increased international understanding and coordination for the protection of certain migratory sharks.[84] A February 2010 study by Barbara Block of Stanford University estimated the world population of great white sharks to be lower than 3,500 individuals, making the species more vulnerable to extinction than the tiger, whose population is in the same range.[85]
Fishermen target many sharks for their jaws, teeth, and fins, and as game fish in general. The great white shark, however, is rarely an object of commercial fishing, although its flesh is considered valuable. If casually captured (it happens for example in some tonnare in the Mediterranean), it is misleadingly sold as smooth-hound shark.
In Australia[edit source | edit]
The great white shark was declared as Vulnerable by the Australian Government in 1999 due to significant population decline and is currently protected under the Environmental Protection and Biodiversity Conservation (EPBC) Act.[86] The causes of decline prior to protection included mortality from sport fishing harvests as well as being caught in beach protection netting.[87]
The national conservation status of the great white shark is reflected by all Australian states under their respective laws, granting the species full protection throughout Australia regardless of jurisdiction.[86] In fact, many states had prohibited the killing or possession of great white sharks prior to national legislation coming into effect. The great white shark is further listed as Threatened in Victoria under the Flora and Fauna Guarantee Act, and as rare or likely to become extinct under Schedule 5 of the Wildlife Conservation Act in Western Australia.[86]
In 2002, the Australian government created the White Shark Recovery Plan, implementing government-mandated conservation research and monitoring for conservation in addition to federal protection and stronger regulation of shark-related trade and tourism activities.[87] An updated recovery plan was published in 2013 to review progress, research findings, and to implement further conservation actions.[88] A study in 2012 revealed that Australia's White Shark population was separated by Bass Strait into genetically distinct eastern and western populations, indicating a need for the development of regional conservation strategies.[89]
Presently, human-caused shark mortality is continuing, primarily from accidental and illegal catching in commercial and recreational fishing as well as from being caught in beach protection netting, and the populations of great white shark in Australia are yet to recover.[88]
In New Zealand[edit source | edit]
As of April 2007, great white sharks were fully protected within 370 kilometres (200 nmi) of New Zealand and additionally from fishing by New Zealand-flagged boats outside this range. The maximum penalty is a $250,000 fine and up to six months in prison.[90]
In North America[edit source | edit]
In 2013, great white sharks were added to California's Endangered Species Act. From data collected, the population of great whites in the North Pacific is estimated to be fewer than 340 individuals. Research also reveals these sharks are genetically distinct from other members of their species elsewhere in Africa, Australia, and the east coast of North America, having been isolated from other populations. [91]
See also[edit source | edit]
References[edit source | edit]
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- ^ a b c d Fergusson, I., Compagno, L.; Marks, M. (2000). "Carcharodon carcharias in IUCN 2012". IUCN Red List of Threatened Species, Vers. 2009.1. International Union for Conservation of Nature and Natural Resources. Retrieved October 28, 2009. (Database entry includes justification for why this species is vulnerable)
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- ^ Spawn of Jaws
- ^ R. Aidan Martin. "White Shark Breaching". ReefQuest Centre for Shark Research. Retrieved April 18, 2012.
- ^ Martin, R. A.; Hammerschlag, N.; Collier, R. S.; Fallows, C. (2005). "Predatory behaviour of white sharks (Carcharodon carcharias) at Seal Island, South Africa". Journal of the Marine Biological Association of the UK 85 (5): 1121. doi:10.1017/S002531540501218X.
- ^ Rice, Xan (2011-07-19). "Great white shark jumps from sea into research boat". The Guardian (London: Guardian Media Group). Retrieved 2011-07-20. "Marine researchers in South Africa had a narrow escape after a three-metre-long great white shark breached the surface of the sea and leapt into their boat, becoming trapped on deck for more than an hour. [...] Enrico Gennari, an expert on great white sharks, [...] said it was almost certainly an accident rather than an attack on the boat."
- ^ a b Pyle, Peter; Mary Jane Schramm, Carol Keiper, Scot D. Anderson (26 August 2006). "PREDATION ON A WHITE SHARK (CARCHARODON CARCHARIAS) BY A KILLER WHALE (ORCINUS ORCA) AND A POSSIBLE CASE OF COMPETITIVE DISPLACEMENT". Society of marine mammalogy (USA: Marine Mammal Science) 15 (2): 563–568. doi:10.1111/j.1748-7692.1999.tb00822.x. Archived from the original on 2012-03-22. Retrieved 8 May 2010.
- ^ a b "Nature Shock Series Premiere: The Whale That Ate the Great White". Tvthrong.co.uk. 1997-10-04. Retrieved 2010-10-16.
- ^ "Killer Whale Documentary Part 4". youtube.com.
- ^ a b c Turner, Pamela S. (Oct/Nov 2004). "Showdown at Sea: What happens when great white sharks go fin-to-fin with killer whales?". National Wildlife (National Wildlife Federation) 42 (6). Archived from the original on 2011-01-16. Retrieved 2009-11-21.
- ^ Benchley, Peter (April 2000). "Great white sharks". National Geographic: 12. ISSN 00279358. "considering the knowledge accumulated about sharks in the last 25 years, I couldn't possibly write Jaws today ... not in good conscience anyway ... back then, it was OK to demonize an animal."
- ^ McCabe, Meghan. "Sharks: Killing Machines?"
- ^ Tricas, T.C.; John McCosker (1984). "Proceedings of the California Academy of Sciences". Predatory behavior of the white shark, Carcharodon carcharias, and notes on its biology 43 (14): 221–238.
- ^ "ISAF Statistics for Worldwide Unprovoked White Shark Attacks Since 1990". February 10, 2011. Retrieved 2011-08-19.
- ^ "A Great White Named Schatzi". December 28, 2005. Archived from the original on 2010-01-27. Retrieved 2010-01-19.
- ^ "Muriwai shark most likely a great white". 3 News NZ. February 28, 2013.
- ^ "Shark attack victim's family embrace in sea". Stuff.co.nz. February 28.
- ^ "Sharks and rays". Te Ara, the Encyclopedia of New Zealand. February 27, 2013.
- ^ "Swimmer dies after shark attack". 3 News NZ. February 27, 2013.
- ^ "Unprovoked White Shark Attacks on Kayakers". Shark Research Committee. Retrieved 14 September 2008.
- ^ Tricas, Timothy C.; McCosker, John E. (1984). "Predatory Behaviour of the White Shark (Carcharodon carcharias), with Notes on its Biology". Proceedings of the California Academy of Sciences 43 (14): 221–238.
- ^ "Great white shark sets record at California aquarium". USA Today. 2004-10-02. Retrieved 2006-09-27.
- ^ Gathright, Alan (2004-09-16). "Great white shark puts jaws on display in aquarium tank". San Francisco Chronicle. Retrieved 2006-09-27.
- ^ "White Shark Research Project". Monterey Bay Aquarium. Retrieved 2006-09-27.
- ^ Squatriglia, Chuck (2003-09-01). "Great white shark introduced at Monterey Bay Aquarium". San Francisco Chronicle. Retrieved 2006-09-27.
- ^ "Learn All About Our New White Shark". "Monterey Bay Aquarium". Retrieved 2009-08-28.
- ^ "Electroreception". Elasmo-research. Retrieved 2006-09-27.
- ^ "Shark cage diving". Department of Environment, Water and Natural Resources. Archived from the original on 2013-04-09. Retrieved 11 March 2013.
- ^ Squires, Nick (1999-01-18). "Swimming With Sharks". BBC. Archived from the original on 2003-08-17. Retrieved 2010-01-21.
- ^ Simon, Bob (2005-12-11). "Swimming With Sharks". 60 Minutes. Retrieved 2010-01-22.
- ^ a b "Blue Water Hunting Successfully". Blue Water Hunter. Archived from the original on 2012-08-18. Retrieved 20 August 2012.
- ^ "Shark Attacks Compared to Lightning". Florida Museum of Natural History. 2003-07-18. Retrieved 2006-11-07.
- ^ Hamilton, Richard (2004-04-15). "SA shark attacks blamed on tourism". BBC. Archived from the original on 2012-03-23. Retrieved 2006-10-24.
- ^ "White Shark Manifesto-kelp Forests". World News. Retrieved 20 August 2012.
- ^ "Regulation of Trade in Specimens of Species Included in Appendix II". CITES (1973). Retrieved April 8. 2012.
- ^ "MEMORANDUM OF UNDERSTANDING ON THE CONSERVATION OF MIGRATORY SHARKS". Convention on Migratory Species. 2010-02-12. Archived from the original on 2013-04-20. Retrieved 31 August 2012.
- ^ Sample, Ian (19 February 2010). "Great white shark is more endangered than tiger, claims scientist". The Guardian. Retrieved 14 August 2013.
- ^ a b c Government of Australia. "Species Profile and Threats Database - Carcharodon carcharias — Great White Shark". Retrieved 2013-08-21.
- ^ a b Environment Australia (2002). White Shark (Carcharodon carcharias) Recovery Plan (Report). http://www.environment.gov.au/coasts/publications/gwshark-plan/pubs/greatwhiteshark.pdf.
- ^ a b Government of Australia Department of Sustainability, Environment, Water, Population and Communities (2013). Recovery Plan for the White Shark (Carcharodon carcharias) (Report). http://www.environment.gov.au/biodiversity/threatened/publications/recovery/pubs/white-shark.pdf.
- ^ Blower, Dean C.; Pandolfil, John M.; Bruce, Barry D.; Gomez-Cabrera, Maria del C.; Overnden, Jennifer R. (2012). "Population genetics of Australian white sharks reveals fine-scale spatial structure, transoceanic dispersal events and low effective population sizes". Marine Ecology Progress Series 455: 229–244. doi:10.3354/meps09659.
- ^ "Great white sharks to be protected". New Zealand Herald. 2006-11-30. Retrieved 2006-11-30.
- ^ Kristene Quan (March 04, 2013). "Great White Sharks Are Now Protected under California Law". time.com.


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Eldridge SS
Soft, comfortable, and super-versatile, this short sleeve buttoner features an advanced rayon blend fabric that protects against harmful UV rays. A subtle checkered pattern goes with just about anything in your closet.
- Feature List
- Soft, Sanded, Mid-Weight Woven Fabric
- Ultraviolet Protection Factor (UPF) 20
- Marmot UpCycle® Product with Recycled Polyester
- Durable Flat Felled Seams with Contrast Interior Stitch
- Straight Hem and Single Patch Pocket
- Main Materials
- 77% Polynosic Rayon, 15% Polyester, 8% Recycled Polyester 4.2oz/yd
- Fit
- Regular Fit
- Weight
- 0lbs 7.8oz (221.1g)
What is it?
UPF stand for Ultraviolet Protection Factor. Clothing can protect you from the sun's ultraviolet rays. It all depends on the fiber content, weave, weight of fabric and color.
So what's the difference between UPF and SPF?
SPF stands for the Sun Protection Factor, most commonly associated with sunscreen. This measures the amount of time it takes for skin to burn. UPF on the other hand stands for Ultraviolet Protection Factor, which is a measure of the amount of UV radiation that penetrates a fabric and reaches your skin. For example, a fabric rated with a UPF of 20 will allow only 1/20th of the sun's UV rays to pass through.
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Wearing a UPF fabric would greatly reduce your exposure to UV rays, (where it covers your body). Dark colors and tight weaves will have higher UPF ratings. As well, nylons and polyesters are better than plain cotton because they reflect radiation.
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Why do we encourage proper care of our clothing and gear?
Because you have invested in (or are thinking about investing in) one of the most technically advanced pieces of apparel or equipment you'll ever own and we want to make sure you have the information you need to protect and care for your purchase. Proper care assures you will optimize the performance of your Marmot product and maximize its service-life.
Clothing Care
- Machine wash cold with like colors
- Powdered detergent
- No fabric softeners
- Warm iron when needed
- Only non-chlorine bleach when necessary
- Dry clean with any solvent except trichloroethylene
- Tumble dry low
- Remove promptly


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North Face
TNF Logo Beanie (Boy's) (out-of-stock)
Out of Stock Product Number: 22119
The TNF Logo Beanie by The North Face has been one of the most widely spotted cold weather hat in the outdoor climbing competitions for the last four years. Standing outside for six hours, trying to complete 10 of your hardest boulder problems, there is a whole lot of warming up and then cooling down. The one thing that is most necessary out there is a good warm hat.
* This product does not qualify for shipping to all countries.
- Thermally efficient knit
- Fleece ear band
Gender: Youth
Weight: 42.45 g (1.5 oz)
Season: F13
Vendor ProductId: AV6Q
Review ProductId: 13162
Reviewed by 1 customer
Displaying review 1
- All-black would be fine
- Bad colors and design
- Warm
- Extra large-black wanted
- Poor Fit
- Unattractive Design
Best Uses
- Athletics
- Extreme Cold
Comments about TNF Logo Beanie (Boy's):
I wear it backcountry skiing. It is too small and has a tendency to sneak up and uncover the lower part of my ears.
- Sizing:
- Feels full size too small
Displaying review 1


text:
An androgynous kiss is captured as an explosion of color in this museum-quality giclée print by legendary L.A. artist and photographer Austin Young. With a body of work that challenges conceptions of gender, beauty, and their nexus, the "pin-up," Young's photos are not only provocative, they push the boundaries of acceptance. One of an edition of 100, this fine art print is numbered and signed by the artist.
Unframed. Austin Young is one of three members of the Los Angeles-based public art collective, Fallen Fruit.
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Top Definition
The realm in which the flims "Clerks," "Mallrats," "Chasing Amy," "Dogma," and "Jay and Silent Bob Strike Back," take place. These films were all directed by Kevin Smith and all include the characters Jay and Silent Bob, sometimes known as Bluntman and Cronic.
Dogma is my favorite movie in the askewniverse.
af Frank Booth
1. januar 2005


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Decimal Degrees: Latitude: 38.8915008 Longitude: -77.0158096
Share your comments and photos of Jackson Hall (historical), a Building in District of Columbia County, DC
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Airport: Anacostia Helicopter Facility , Bolling Air Force Base Heliport
Area: Bolling Anacostia Tract , District of Columbia Impound Lot
Bridge: Market Bridge (historical)
Building: National Green House (historical) , National Gallery of Art - East Building , American Colonization Society Hall (historical) , Embassy of Canada , May-Smallwood House (historical) , Moran Building , Edward Simon Lewis House , Washington Jail (historical) , Freemasons Hall (historical) , East Capitol Street Car Barn , Saint Charles Hotel (historical) , Judiciary Square Rowhouses (historical) , Blagden Row (historical) , Tyler House (historical) , National Air and Space Museum , Donohoe Building , Transpoint Building , Hubert Humphrey Building , Frances Perkins House , Mary E Switzer Building , Department of Education , Government Printing Office , National Hotel (historical) , Gadsbys Hotel (historical) , Wheat Row , Jackson Hall (historical) , Ryders Castle , Indian House (historical) , Washington House (historical) , Mades Hotel (historical) , American Theatre (historical) , General Accounting Office , Rayburn House Office Building , District of Columbia Municipal Center , United States Court House , House Office Building Annex 2 , Department of Labor Building , Food and Drug Administration Building , Department of Health and Human Services Building , New National Aeronautical Space Administration Building , Railroad Retirement Board , Purdy Court (historical) , Randall Building , Washington Bank (historical) , Jackson Hotel (historical) , United States Hotel (historical) , District of Columbia Public Library-Southwest Neighborhood Branch , Environmental Protection Agency , Federal Home Loan Bank Board Building , Kreeger Theatre , United States Tax Court Building , Washington Metropolitan Area Transit Authority Headquarters , Superior Court of the District of Columbia - Criminal Division , Old City Hall , Duncanson-Cranch House , Odeon Theatre (historical) , Harrison Apartment Building , Pension Building (historical) , National Building Museum , Voice of America Building , District of Columbia Fire and Emergency Medical Services - Training Academy , District of Columbia Fire and Emergency Medical Services - Fire Prevention Division , District of Columbia Fire and Emergency Medical Services Engine Company 7 , District of Columbia Fire and Emergency Medical Services Engine Company 2 , District of Columbia Fire and Emergency Medical Services Engine Company 3 , District of Columbia Fire and Emergency Medical Services Engine Company 13 , Superior Court of the District of Columbia - Crime Victims Compensation Program , Superior Court of the District of Columbia- Clerk of the Court , Metropolitan Police Boys and Girls Clubs , Washington District of Columbia Police Chief Headquarters , Superior Court of the District of Columbia - Moultrie Courthouse , Washington District of Columbia Police Department District 1 , Washington District of Columbia Police Department - Training , Washington District of Columbia Police Department - Recruitment , Myrene Apartment Building , National Museum of the American Indian , United States Court of Military Appeals , Washington Design Center , Thomas Law House , Lillian and Albert Small Jewish Museum , Newseum , Amidon Before and After School Center , Big Mamas Childrens Center , Department of Labor Day Care Center , District of Columbia Court of Appeals Building , District of Columbia Superior Court Child Care Center , Georgetown Law Early Learning Center , Second Baptist Church Day Care Center , Social Security Building , Southwest Child Development Center , Tiny Findings Day Care Center , United States Coast Guard Headquarters Building , Summer House , Southwest Branch Library , Washington Highlands Branch Library , Samuel P Langley IMAX Theater , Albert Einstein Planetarium , Metropolitan Police Department Headquarters
Canal: Washington City Canal (historical)
Cape: Greenleaf Point , Giesboro Point , Buzzard Point
Church: Gorsuch Methodist Church (historical) , Holy Rosary Catholic Church , German Evangelical Lutheran Church (historical) , Holy Rosery Church , Wesley Chapel (historical) , Saint Marys Catholic Church , Capital Memorial Adventist Church (historical) , Saint Marys Roman Catholic Church (historical) , Trinity Church (historical) , Shilo Baptist Church (historical) , Bethel Penecostal Tabernacle of the Assemblies of God , Carron Baptist Church , First Trinity Lutheran Church , Westminster Presbyterian Church , Zion Wesley Chapel (historical) , German Church Saint Paul , Friendship Baptist Church , Second Union Baptist Church , Adas Israel Synagogue
Civil: Southwest Quadrant , Turkey Buzzard Plantation (historical) , Cerne Abbey Manor (historical) , Gordons Meadow (historical)
Hospital: Judiciary Square Hospital (historical) , City Hospital (historical) , Hadley Memorial Hospital , Federal City Shelter Clinic , Southwest Community Health Center
Locale: Greenleaf Point Golf Course , Germuiller Row , Commerce Building Plaza , District of Columbia Impounding Lot , Dowsons Tavern (historical) , Shadds Tavern (historical) , Hash Row , Junior Village , Chinatown (historical) , Waterfront-SEU Metro Station , Federal Center SW Metro Station , Judiciary Square Metro Station , District of Columbia Village , James Creek Marina , Buzzard Point Marina , Corinthian Yacht Club , Waterside Mall , English Hill , Shepherd Station (historical)
Military: Anacostia Annex , Fort Leslie J McNair , Bolling Air Force Base
Military (Historical): Fort Greble (historical)
Park: President Ulysses S Grant Memorial , Joseph Darlington Fountain , Randall Recreation Center , National Law Enforcement Officers Memorial , Freedom Statue , Acacia Griffins Sculpture , The Majesty of Law Sculpture , Sir William Blackstone Statue , Fort Greble Recreation Center , The Spirit of Justice Park , Robert A Taft Memorial and Carillon , Abraham Lincoln Statue , Brigadier General Albert Pike Statue , Peace Monument , Judiciary Square , President James Garfield Memorial , East Seaton Park , West Seaton Park , Hoover Playground , Botanic Gardens (historical) , James Abram Garfield Memorial , Chief Justice John Marshall Statue , Man Controlling Trade Sculpture , Titanic Memorial , John Marshall Place Park , General Meade Statue , Bartholdi Fountain , Union Square , Randall Pool , Victims of Communism Memorial , Spring Grotto , Civil War Sailors Statue , King-Greenleaf Recreation Center , Bald Eagle Recreation Center , Fort Greble Recreation Center , M L King Recreation Center , Japanese American Memorial , Flamingo Fountain , Amidon-Greenleaf Playground , Washington Area Law Enforcement Officers Memorial
Populated Place: Judiciary Square , Southwest , Giesboro , East End , Buzzard Point , Bellevue
Post Office: Southwest Station Post Office , Ford Station Post Office , Fort McNair Post Office , Francis Perkins Station Post Office , Naval Research Laboratory Post Office
Reservoir: Capitol Reflecting Pool
School: World Public Charter School of Washington , Techworld Public Charter School , Gales School , Joseph Gales School (historical) , Syphax Elementary School (historical) , S J Bowen School (historical) , Saint Marys School (historical) , Saint Patricks School (historical) , Saint Vincent De Paul School (historical) , Smallwood School (historical) , Leckie Elementary School , Southeastern University , Georgetown University Law Center , Greenleaf School (historical) , Hawthorne High School , Randall Junior High School , Ambush School , Bell School , Columbia Law School (historical) , National Defense University , Industrial College of the Armed Forces , Army War College , Amidon Elementary School , Bowen Elementary School
Stream: Saint James Creek (historical)
Summit: Bald Eagle Hill
236 Places found nearby
New! Tell others about this location or share a photo!
Time to build: 0.0940 Secs | Cached: 19-Apr-15 06:49 PM


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Please Note: By clicking a link to any resource listed on this page, you will be leaving this site.
Celiac Disease Foundationhttp://www.celiac.org/The Celiac Disease Foundation provides support, information and assistance to people affected by celiac disease and dermatitis herpetiformis. The site provides information on celiac disease and helps people locate support groups.
Celiac Sprue Associationhttp://www.csaceliacs.org/This non-profit organization helps people with celiac disease and dermatitis herpetiformis. Find gluten-free products, recipes, support groups, and more.
Gluten Intolerance Grouphttp://www.gluten.net/This non-profit organization offers information, support, and resources for people living with celiac disease.
North American Society for Pediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN)http://www.naspghan.org/NASPGHAN works to help children and adolescents with digestive disorders.
Children's Digestive Health and Nutrition Foundation (CDHNF)http://www.cdhnf.orgThe CDHNF website provides information on gastroesophageal reflux disease (GERD).
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You are looking at historical revision 25634 of this page. It may differ significantly from its current revision.
Mini-tutorial on explicit (and implicit) renaming macros in Chicken
The following is an attempt to explain, how to write hygienic macros in Chicken with explicit renaming. It supposes, that the reader knows, how to write other low-level-macros like define-macro in Chicken-3 and other Schemes or defmacro in Lisp. As you will see, explicit renaming macros are even easier to write than those with define-macro. This is because there is a brute force method to avoid variable capture.
Let's consider a trivial macro a la Chicken-3 without any considerations on hygiene and variable capture:
(define-macro swap! ; wrong
(lambda (x y)
`(let ((tmp ,x))
(set! ,x ,y)
(set! ,y tmp))))
or, in short form
(define-macro (swap! x y) ; wrong
`(let ((tmp ,x))
(set! ,x ,y)
(set! ,y tmp)))
You might be surprised, but the replacement text, that within the backquotes, need not be changed in an explicit renaming macro, at least in a first step. What has to be changed, is the signature: explicit renaming transformers are always procedures of three variables, usually called form, rename, compare?, which has to be wrapped into an er-macro-transformer call:
(define-syntax swap!
(lambda (form rename compare?)
`(let ((tmp ,x))
(set! ,x ,y)
(set! ,y tmp)))))
and you have to destructure the form argument, which is the whole macro-from, (swap! x y) in the example, to fill in the ellipsis above. That is
(define-syntax swap! ; wrong
(lambda (form rename compare?)
(let ((x (cadr form)) (y (caddr form)))
`(let ((tmp ,x))
(set! ,x ,y)
(set! ,y tmp))))))
In this form, the new macro is the same as our first attempt with define-macro. We haven't bothered about variable capture or hygiene at all. But this macro already works. You can test it, say with
(let ((x 'x) (y 'y))
(swap! x y)
(list x y))
and see if it does what it is supposed to do. Of course, it is not correct, since if a client uses tmp as one of his or her arguments, the macro will crash.
In the classical macro systems, defmacro in Common Lisp or define-macro in some Schemes, you now have to think carefully, which macro variables are in danger of variable capture and use an uninterned symbol for them, tmp in the current example. Worse than that, contrary to Common Lisp, Scheme allows to use any name for variables, even keyword names as let, set!, ... so that define-macro can never create a hygienic swap! macro. Here is, where renaming comes into the play. You don't need gensym, use rename instead. And you needn't bother, which symbol to rename, rename all.
What does that mean, "all"? It's easy in the present example, everything within the backquote, except those symbols, which are already unquoted. But in more complicated examples, you should use expand, to see the replacement text of your macro calls.
(pp (expand '(swap! x y)))
will result in the replacement text
(let ((tmp x))
(set! x y)
(set! y tmp))
Only x and y are arguments of your swap! call, hence everything else in the replacement text should be renamed: namely let, tmp and set!. So a hygienic version of swap! would be
(define-syntax swap!
(lambda (form rename compare?)
(let ((x (cadr form)) (y (caddr form)))
`(,(rename 'let) ((,(rename 'tmp) ,x))
(,(rename 'set!) ,x ,y)
(,(rename 'set!) ,y ,(rename 'tmp)))))))
If you repeat the expand call above, you will get the same replacement text, but with numbers suffixed to the renamed symbols, something like
(let11 ((tmp12 x))
(set!13 x y)
(set!13 y tmp12))
These renamed symbols have the same meaning as the original names without suffixes, but serve as aliases which the client cannot use under any circumstances.
Note, that the two appearances of tmp and set! are renamed to the same alias, the rename operator is referentially transparent. Note also, that these renamed symbols are much easier to interpret than gensym'ed ones!
I personally do not like these rename calls within the backquoted expression, because you loose the visual similarity between the backquoted expression and the resulting replacement text. Therefore I prefer this version, which is equivalent
(define-syntax swap!
(lambda (form rename compare?)
(let (
(x (cadr form))
(y (caddr form))
(%tmp (rename 'tmp))
(%let (rename 'let))
(%set! (rename 'set!))
`(,%let ((,%tmp ,x))
(,%set! ,x ,y)
(,%set! ,y ,%tmp))))))
You can think of the two characters ,% in the template as an identity operator.
We havn't used the compare? argument in the transformer in this example. What's its role?
Well, some macros use special symbols verbatim, else and => in cond for example. With compare? it's possible to check, if these symbols, which might appear verbatim in a list, have the same meaning as their renamed variants (rename 'else), (rename '=>). For example, if else appears as the car of a list, lst say, you can code something like
(if (compare? (car lst) (rename 'else)) ...)
You see, explicit renaming macros are a bit more verbose than classical ones with define-macro. But everybody who is able to write the latter, is able to write the former as well. It's even easier!
Implicit renaming macros
But it can still be improved. Above, I said "You need'nt bother which symbol to rename, rename all". Well, "all" is something which can perfectly be done by a machine. Consequently, since the advent of Chicken version 4.7, there is another low level macro system, based on ir-macro-transformer, which does this "rename all" in the background.
In explicit renaming macros, I had to tell the compiler explicitly, what to rename. Every symbol not renamed would break hygiene. In implicit renaming macros, the roles are reversed: I have to tell the compiler explicitly, which symbol should break hygiene, everything else is renamed, whence hygienic. A hygienic swap! macro now looks like this
(define-syntax swap!
(lambda (form inject compare?)
(let ((x (cadr form)) (y (caddr form)))
`(let ((tmp ,x))
(set! ,x ,y)
(set! ,y tmp))))))
Note, that the second argument to the transformer is now called inject. It's used to "inject" a symbol unrenamed into the replacement text. Note further, that there is no need to gensym tmp as in define-macro. And last but not least, it's obligatory to wrap the transformer into an ir-macro-transformer call: the compiler must know, which low-level system to compile, after all.
For implicit renaming macros, the third argument to the transformer is now used a bit differently, for example
(if (compare? 'else (car lst)) ...)
Destructuring the macro-code
Up to now, we have always destructured the macro-code, (swap! x y), by hand. define-macro did it automatically. Is there a way to do it automatically with explicit- and implicit-renaming-macros as well?
Off course, you can use match from the matchable package or an appropriate binding operater from the bindings package (bind or bind-case for example) to do the destructuring. Then instead of
(let ((x (cadr form)) (y (caddr form))) ...)
you could write for example
(match form
((_ x y) ...))
provided you had wrapped the code into something like
(import-for-syntax (only matchable match))
In simple macros like swap!, the use of match or bind-case is not that much help. But a lot of macros have complicated nested list structures as macro-code. Then automatic destructuring is almost a necessity. Moreover, it does error-checking for free ...
Hiding the matching process
To facilitate the use of low-level-macros even more, you can abstract away not only the renaming but also the matching process, by packaging it -- you guess it -- in a macro, conveniently one which looks much like syntax-rules and should hence be called ir-macro-rules. An explicit renaming version called er-macro-rules exists as well. To use them, they must be imported for syntax
(import-for-syntax (only low-level-macros ir-macro-rules er-macro-rules))
ir-macro-rules pairs possible macro-codes (where the macro name is conveniently replaced by an underscore) with expressions, which evaluate to the macro-expansion.
With it, our old friend swap! would look like this
(define-syntax swap!
(ir-macro-rules ()
((_ x y)
`(let ((tmp ,x)) (set! ,x ,y) (set! ,y tmp)))))
The empty list in this macro shows, that the generated macro is hygienic. To implement unhygienic macros, you have to list those names, which should pollute the local namespace.
If you like it a bit more low-level and want to do the renaming yourself, you can code
(define-syntax swap!
(er-macro-rules (%tmp %let %set!)
((_ x y)
`(,%let ((,%tmp ,x)) (,%set! ,x ,y) (,%set! ,y ,%tmp)))))
where all renamed symbols are listet in er-macro-rules' first argument.
For details see low-level-macros.
You'll find there define-macro as well, and believe it or not
(define-macro (swap! x y)
`(let ((tmp ,x))
(set! ,x ,y)
(set! ,y tmp)))
is not only correct, but hygienic as well!
Low level macros are really great ...
Initial version
Jun 09, 2009
Sep 13, 2011