Table of Contents
Spermatogenesis creates functional sperm from an initially undifferentiated germ cell. In the nematode Caenorhabditis elegans, both males and hermaphrodites engage in spermatogenesis. The hermaphrodite germ line, like that of the male, initiates spermatogenesis during the L4 larval stage. The hermaphrodite germ line differs from that of the male because it ceases spermatogenesis and switches to oogenesis during the adult stage. Each hermaphrodite stores her sperm and uses them to fertilize her oocytes. Many mutants have been identified where hermaphrodite self-fertility is disrupted. If such a self-sterile hermaphrodite is mated to a wild-type male, mutant hermaphrodites that either lack sperm or contain defective sperm will produce outcross progeny. Easily implemented tests are then applied to identify the subset of these mutants that produce defective sperm. Currently, more than 44 genes are known that are required for normal spermatogenesis. This chapter discusses the 25 best-understood genes that affect spermatogenesis and mutants are grouped based on the cellular structure or process that is affected. C. elegans spermatozoa lack an acrosome and a flagellum, which are organelles found in the spermatozoa produced by most other species. Like other nematodes, C. elegans spermatozoa move by crawling using a single pseudopod. Wild-type spermatogenesis and its defects in mutants can be studied in vivo because the animal is transparent and in vitro because a simple, chemically defined medium that supports development has been discovered. Unlike nearly all other C. elegans cells, homogeneous sperm can be obtained in sufficient quantities to permit biochemical analyses.
Spermatogenesis is the process that creates sperm from initially undifferentiated germ cells (see Sex determination in the germ line). In diocious animals, this process occurs exclusively in males. While C. elegans spermatogenesis occurs in males, it also occurs during a stage of germline development in the hermaphrodite prior to the onset of oogenesis (see Sex determination in the germ line). Wild-type spermatogenesis and its defects in mutants can be studied in vivo because the animal is transparent and in vitro because a medium that supports development is available (Machaca et al., 1996; Nelson and Ward, 1980). Unlike nearly all other C. elegans cells, homogeneous sperm can be obtained in sufficient quantities to permit biochemical analyses (Klass and Hirsh, 1981; Nelson et al., 1982). This chapter focuses on genes that are sperm-specific regulators, and genes affecting germline development more generally are described elsewhere (see Sex determination in the germ line, RNA-binding proteins, Germline proliferation and its control and Specification of the germ line).
Development of sperm in C. elegans males has been described in detail (Kimble and Ward, 1988; Ward, 1986; Ward et al., 1981; Wolf et al., 1978) and these cellular events are reviewed in Figure 1. The primary spermatocyte initially forms in syncytium with a cytoplasmic core called the rachis. Upon entering meiosis, the primary spermatocyte buds off the rachis and completes development without any requirement for intimate association with other cells. As in most cells, nuclear divisions are closely coordinated with cytokinesis and other aspects of cytodifferentiation. Meiosis I divides the 4N primary spermatocyte nucleus into two 2N nuclei in secondary spermatocytes. The cytokinesis that accompanies meiosis I is either complete (not shown) or partial (2 in Figure 1A). Either way, the resulting cells are secondary spermatocytes and they immediately initiate meiosis II. Meiosis II produces two haploid spermatids from each 2N secondary spermatocyte. Spermatids form by budding from an anucleate residual body (Movie 1), and spermatids lack many cellular constituents present in the secondary spermatocyte. Material within the residual body, which includes most voltage-gated ion channels, tubulin, actin and all ribosomes (Machaca et al., 1996; Ward, 1986) is apparently resorbed (Kimble and Ward, 1988; Nelson et al., 1982; Ward, 1986; Ward et al., 1981; Wolf et al., 1978). Sessile spermatids lack ribosomes and have no new protein synthesis as they complete differentiation into motile spermatozoa (Ward et al., 1983). The cytologically obvious structures that segregate into spermatids during budding include its nucleus, multiple mitochondria and multiple specialized lysosome-like organelles named fibrous body-membranous organelles (FB-MOs).
The meiotic divisions of spermatogenesis are coordinated with the morphogenesis of FB-MOs (Ward et al., 1981; Wolf et al., 1978). In syncytial pachytene spermatocytes (Figure 1), the MOs form from the Golgi apparatus and FBs form in close association with the MOs (Roberts et al., 1986). Growth of the FBs occurs within a MO-derived membrane envelope in primary spermatocytes (Figure 1B1). As spermatids bud, the double membrane surrounding the FB retracts into the MO and the filamentous major sperm protein (MSP) contents (Figure 1B3) depolymerize and disperse throughout the spermatid cytoplasm. These FB-free MOs (Figure 1B4) localize near the spermatid plasma membrane (pm in Figure 1B4). Spermiogenesis is the process during which a spermatid becomes a spermatozoon. MO head membranes (h, in Figure 1B4) fuse and deposit their contents on the plasma membrane of the cell body as the spermatozoon forms (Figure 1B5). A single pseudopod is extended (red arrows at 3 in Figure 1A), and MSP fibers are confined to the pseudopod (Ward and Klass, 1982) while the nucleus, mitochondria, MOs and other internal membranes are confined to the cell body. Like other nematodes, C. elegans spermatozoa lack a flagellum and crawl using this single pseudopod (see Sperm motility and MSP).
Spermatogenesis is similar in hermaphrodites and males, but there are some significant differences. Spermatids accumulate in the proximal gonad arm after the hermaphrodite germ line has switched to oogenesis (Figure 3A). The first ovulation pushes spermatids into the spermatheca (Figure 3B), where they rapidly undergo spermiogenesis and become spermatozoa (Figure 3C). Many spermatozoa are displaced into the uterus as the egg leaves the spermatheca and they must crawl back into the spermatheca in order to compete for oocytes (Figure 3D-F; Ward and Carrel, 1979).
In males, spermatids are stored in the seminal vesicle. These spermatids are significantly larger than those produced by hermaphrodites (LaMunyon and Ward, 1998). Spermatids undergo spermiogenesis after they are mixed with seminal fluid during ejaculation into the hermaphrodite uterus. The molecular mechanism that activates spermiogenesis in vivo is not known for either sex. However, in vitro, spermatids are activated to become spermatozoa by treatment with several unrelated agents including the ionophore monensin (Nelson and Ward, 1980), proteases, weak bases that alkalinize the cytoplasm (Ward et al., 1983), calmodulin inhibitors (Shakes and Ward, 1989) or the ion channel inhibitor DIDS (Machaca et al., 1996). Normally, male-derived spermatozoa crawl towards and into the hermaphrodite spermatheca. Spermatozoa introduced by a male during copulation have a competitive advantage over hermaphrodite-derived spermatozoa in the struggle to fertilize oocytes (Figure 4; Ward and Carrel, 1979; LaMunyon and Ward, 1995). Artificial insemination is also possible, and male-derived spermatids that are protease treated cannot fertilize oocytes, while spermatids treated with weak bases are competent to participate in fertilization (LaMunyon and Ward, 1994).
C. elegans spermatogenesis mutants (spe or fer) have been identified because they compromise hermaphrodite self-fertility. In wild-type, virtually every sperm fertilizes an oocyte in young hermaphrodites, and the resulting shelled, oval eggs are laid on the agar growth plate (Ward and Carrel, 1979). In contrast, spe/fer mutants lay unfertilized oocytes, which are round, brown cells that lack an eggshell. The differences between laid oocytes and eggs are easily discerned under the dissecting microscope. Mutant, self-sterile hermaphrodites that have a normal appearing germ line can be readily identified following mutagenesis. While some of these mutants never initiate spermatogenesis (see Sex determination in the germ line), most produce defective sperm. While mutants that fail to initiate spermatogenesis lay a few oocytes, mutants that make defective sperm lay large numbers of unfertilized oocytes (McCarter et al., 1999). Self-sterile hermaphrodites can be mated to wild-type males, allowing the recovery of a spe or fer mutation among the outcross progeny. This straightforward screen has allowed identification of > 44 genes that affect spermatogenesis (reviewed by L'Hernault, 1997; L’Hernault and Singson, 2000; S. L’Hernault, unpublished; S. Ward, unpublished) and several additional genes were identified in other studies (Amiri et al., 2001; Luitjens et al., 2000; Subramaniam and Seydoux, 2003); representative mutants are shown in Figure 5.
Translational control is widely employed in differentiating cellular systems (reviewed by Gebauer and Hentze, 2004), and two genes have been identified that act as spermatogenesis-specific regulators of translation.
The cpb-1 gene encodes a cytoplasmic polyadenylation element binding protein. Although this gene is expressed in both the testes and the ovary, RNAi experiments reveal that it is required for spermatogenesis but not oogenesis. cpb-1(RNAi) hermaphrodites lay unfertilized oocytes, like spe/fer mutants. Examination of the spermatheca reveals that cpb-1(RNAi) hermaphrodites accumulate spermatocytes and many of these cells fail to complete meiosis. These results suggest that cpb-1 regulates the translation of one or more mRNAs that are critical for completion of meiosis and perhaps other processes during spermatogenesis (Luitjens et al., 2000).
The ife-1 gene encodes an eIF4E mRNA cap binding protein that is associated with P granules during germline proliferation. RNAi of the ife-1 gene results in a temperature sensitive delay in the completion of spermatogenesis, but the majority of the resulting sperm are not competent to engage in fertilization. About 80% of ife-1(RNAi) treated hermaphrodites are self-sterile and the remaining 20% have reduced broods. These data suggest that IFE-1 regulates translation of one or more RNA that are critical for spermatogenesis and sperm function (Amiri et al., 2001).
Like other animals, C. elegans meiosis occurs during both oogenesis and spermatogenesis, and many meiotic processes are similar in the two germ lines. However, two genes that are involved in meiosis can show specific defects during spermatogenesis.
Six dominant wee-1.3(gf) Spe mutants have been discovered and they have no evident defects during oogenesis or in any proliferating somatic tissue. This observation is surprising because Wee1p type kinase is widely expressed (A. Golden, personal communication; Lamitina and L'Hernault, 2002) and probably negatively regulates the C. elegans cdc2p ortholog ncc-1 (Boxem et al., 1999); cdc2p (or its orthologs) is a master regulator of both mitotic and meiotic divisions in eukaryotes (Lundgren et al., 1991). The wee-1.3 null phenotype is embryonic/larval lethality, which indicates it plays an essential role in addition to its role during spermatogenesis (Lamitina and L'Hernault, 2002). These independently obtained dominant wee-1.3 mutations are all located in a four amino acid region near the C-terminus and three contain identical mutations. Dominant wee-1.3 mutant spermatocytes enter pachytene of meiosis I, but the nuclear envelope remains intact and the chromatin acquires an ultrastructural appearance that is similar (although ~4X larger) to that seen in wild-type (haploid) spermatids. wee-1.3 dominant mutants do not initiate cytokinesis and they arrest with an undivided nucleus on one side of the primary spermatocyte (Figure 5B) and vacuolated FB-MOs on the opposite side. These data indicate that a sperm-specific pathway negatively regulates WEE-1.3 during the G2/M transition of male meiosis I, and this regulation does not occur in these dominant mutants (Lamitina and L'Hernault, 2002).
puf-8 encodes a pumilio-like RNA binding protein that controls RNA stability and translation. The PUF-8 protein is required redundantly with other PUF proteins to maintain viable germ cells during development (Subramaniam and Seydoux, 1999), but it also plays a partially penetrant, non redundant role in the testes. Primary spermatocytes lacking PUF-8 complete prophase of meiosis I, but then exit meiosis, re-enter mitosis and de-differentiate into tumorous germ cells. This observation indicates that PUF-8 is required for primary spermatocytes to complete meiosis and remain in the spermatogenesis pathway (Subramaniam and Seydoux, 2003).
Several mutants affect FB-MO morphogenesis or function.
The spe-39 gene encodes a novel hydrophilic, cytoplasmic protein that is not specifically associated with FB-MOs in spermatocytes and spermatids. spe-39 mutants arrest as aberrant spermatocytes (Figure 5B) that lack MOs but contain many small vesicles with internal membranes, a distinctive feature of wild-type MOs (Figure 1). A membrane envelope does not surround spe-39 FBs, indicating that some aspects of the FB can form in the absence of MOs. In addition to its role during spermatogenesis, SPE-39 is found in many, if not all, C. elegans cells, and spe-39 RNAi causes embryonic lethality. The spe-39 gene has orthologs in many metazoa, but no homolog was identified in the yeast genome. This observation suggests that the SPE-39 role during FB-MO morphogenesis is a conserved process that requires SPE-39 orthologs in other metazoan cell types (Zhu and L'Hernault, 2003).
The spe-6 gene encodes a casein I type serine threonine kinase (Muhlrad and Ward, 2002). In spe-6 null mutants, the MSP fails to form FBs (Varkey et al., 1993). Consequently, FB-MOs never form, so spe-6 mutants do not form spermatids and arrest as aberrant spermatocytes (Figure 5B). This observation suggests that a regulatory phosphorylation controls FB morphogenesis, but the substrates for the SPE-6 kinase are not currently defined. Non-null mutants reveal that this gene is also involved in regulating spermiogenesis (see Sex-specific aspects of spermiogenesis, below).
The spe-4 gene encodes a sperm-specific presenilin (L'Hernault and Arduengo, 1992); presenilins are intramembranous aspartyl proteases that process other membrane proteins, including the Alzheimer precursor protein in human brain (Xia and Wolfe, 2003). The SPE-4 protein resides in FB-MOs and spe-4 mutants, like spe-39 mutants, develop FBs that are not associated with MOs. spe-4 mutants accumulate aberrant spermatocytes filled with distended MOs that are not associated with FBs (Arduengo et al., 1998).
The spe-5 gene encodes a vacuolar ATPase B subunit (P. Hartley and S.W. L’Hernault, unpublished) that localizes to the FB-MO (E. J. Gleason and S. W. L’Hernault, unpublished). spe-5 mutants form FB-MOs that are greatly distended and vacuolated. Usually, spe-5 null mutants arrest as aberrant spermatocytes that contain four haploid nuclei (Figure 5B), but occasionally a few spe-5 self-progeny are observed so some functional spermatozoa must form (Machaca and L'Hernault, 1997). Because vacuolar ATPases acidify compartments (Nishi and Forgac, 2002), the spe-5 defect may reflect a lack of FB-MO acidification.
The spe-17 gene encodes a small soluble protein with no obvious conserved domains or homologs outside nematodes (L'Hernault et al., 1993). spe-17 mutants form FB-MOs with membrane-attached ribosomes. The consequence is that spe-17 mutants retain ribosomes in the spermatid. The FB can still disassemble and release MSP, but many MOs do not fuse with the cell surface during spermiogenesis (Shakes and Ward, 1989). Motile spermatozoa can still form in spe-17 mutants, and some are competent to engage in fertilization.
spe-10 mutants initiate FB-MO morphogenesis normally, but the membrane surrounding the FB prematurely retracts so that FBs are left in the residual body during spermatid budding. Budded spe-10 spermatids are deficient in MSP and resulting spe-10 spermatozoa are immotile and have vacuolated MOs that do not fuse with the plasma membrane (Shakes and Ward, 1989). The spe-10 gene encodes a four pass integral membrane protein that contains a DHHC domain predicted to be a palmitoyl transferase that is localizes within FB-MOs (Gleason et al. 2006). The presence of this motif implicates SPE-10 function in the posttranslational palmitoylation of target proteins required for proper FB-MO function. In addition to FB-MO defects, both spe-17 and spe-10 mutant males make spermatids that are only ~66% the wild-type size and have nuclei that are eccentrically placed (Shakes and Ward, 1989).
fer-6 mutants makes spermatids in which the FBs detach from the MO but fail to disassemble and release MSP. Many MOs fail to fuse with the plasma membrane in fer-6 mutants, which form abnormal spermatids (Ward et al., 1981).
fer-1 mutants have no apparent defects in the early stages of FB-MO morphogenesis and have normal sized spermatids in which FBs disassemble normally. However, the MOs fail to fuse with the plasma membrane, and fer-1 mutants extend short pseudopods that do not allow normal motility (Roberts and Ward, 1982; Ward et al., 1981). The fer-1 gene encodes a one pass transmembrane protein in the dysferlin family with homology to at least seven human genes (Achanzar and Ward, 1997), including one implicated in limb girdle muscular dystrophy (Bashir et al., 1998). Human dysferlins are probably involved in muscle membrane repair/remodeling (Bansal and Campbell, 2004), which is consistent with the fer-1 membrane fusion defect (Ward et al., 1981).
There are two spe genes that encode known cytoskeletal proteins.
The spe-26 gene encodes an actin binding protein, and mutants usually form aberrant spermatocytes that do not become spermatids. Occasionally, spe-26 mutants make spermatids that become spermatozoa, but these spermatozoa do not participate in fertilization. A spe-26 spermatocyte can complete meiosis and form four haploid nuclei within a single, aberrant cell, but these cells sometimes contain as many as 12 DAPI positive DNA regions (Varkey et al., 1995).
The spe-15 gene encodes a myosin VI that plays a sorting role as spermatids bud from the residual body. spe-15 mutants partially fail in their polarized delivery of mitochondria and FB-MOs to spermatids and actin filaments and microtubules to the residual body. As a consequence, all of these cellular components are distributed to both spermatids and residual bodies during budding. When spe-15 spermatids are protease activated in vitro, resulting spermatozoa usually lack normal pseudopods (Kelleher et al., 2000).
Sperm derived from hermaphrodites and males have two known differences. Male-derived sperm are substantially bigger than hermaphrodite-derived sperm (Figure 3; LaMunyon and Ward, 1995; LaMunyon and Ward, 1998), and the regulatory machinery they utilize for spermiogenesis is sex-specific. Mutant screens for spermatogenesis defects have uncovered four genes (the spe-8 pathway) with hermaphrodite-specific spermiogenesis defects (L'Hernault et al., 1988; Minniti et al., 1996; Nance et al., 1999; Nance et al., 2000; Shakes and Ward, 1989).
spe-8 encodes a predicted SH2 domain containing non receptor tyrosine kinase (P.J. Muhlrad and S. Ward, unpublished).
Hermaphrodites homozygous for a mutation in any spe-8 pathway gene accumulate spermatids that fail to activate into spermatozoa (Figure 5). Unlike most (> 40) spermatogenesis genes, males homozygous for a mutation in any one of these four genes produce spermatozoa that are competent for fertilization. The arrested spermatids present in hermaphrodites that are mutant in the spe-8 pathway can be activated to become spermatozoa if they are exposed to male-derived seminal fluid. However, neither male nor hermaphrodite derived spermatids from either sex are entirely normal; after protease treatment, mutant spermatids have an unusual spiky cytology, whereas wild-type spermatids become cytologically normal spermatozoa (Minniti et al., 1996; Nance et al., 1999; Nance et al., 2000; Shakes and Ward, 1989).
Eighteen non-null spe-6 mutants allow partial bypass of any spe-8 pathway mutant (spe-6 null mutants have defects in FB-MO morphogenesis, see above). These non-null spe-6 mutations are scattered across the polypeptide sequence and some affect non-essential residues in the kinase catalytic region. It is thought that SPE-6 negatively regulates spermiogenesis until an activation signal is sent through the spe-8 pathway. Partial loss of SPE-6 function partly alleviates the need for spe-8 pathway-mediated relief of SPE-6 negative regulation in hermaphrodites (Muhlrad and Ward, 2002). These spe-6 suppressor mutants have also been analyzed in a background that was not mutant for other genes in the spe-8 pathway. In males, spe-6 suppressor mutations show precocious activation of spermatids into spermatozoa. However, there is a large reduction in spermatid numbers due to necrosis, and mutant males rarely sire progeny after copulation. In contrast, hermaphrodite-derived spermatids show only minimal signs of necrosis in spe-6 suppressor mutants (Muhlrad and Ward, 2002).
These data indicate that there are two spermiogenesis pathways, one active in males and one active in hermaphrodites (Nance et al., 2000; Shakes, 1988). The pathway in hermaphrodites has two kinases (SPE-6 and SPE-8), one soluble protein (SPE-27) and two transmembrane proteins (SPE-12 and SPE-29), suggesting it functions in signal transduction. The physiological signal that initiates spermiogenesis in hermaphrodites is not presently known. None of the genes that participate in the spermiogenesis pathway for male-derived spermatids are presently known.
Seven mutants (fer-14, spe-9, spe-13, spe-36, spe-38, spe-41/trp-3 and spe-42) appear to complete spermatogenesis normally but are defective in fertilization (Figure 5; also see Control of oocyte meiotic maturation and fertilization), and five of these genes have been cloned.
The spe-9 gene encodes a one-pass integral membrane protein with 10 EGF-like motifs, which usually have extracellular functions such as adhesive and ligand-receptor interactions (Singson et al., 1999). Transgenes bearing the spe-9 coding sequence in which deletion or point mutations were induced revealed that certain EGF repeats in the predicted SPE-9 protein are more important than others for SPE-9 function during fertilization (Putiri et al., 2004).
The spe-38 gene encodes a novel tetraspan integral membrane protein (Chatterjee et al., 2005). Structurally similar proteins participate in membrane adhesion/fusion during mammalian fertilization, yeast mating and metazoan tight junction formation (Hemler, 2003), but the precise role of SPE-38 remains to be determined.
The fer-14 gene encodes a novel one pass transmembrane protein that is nematode specific. (T. Kroft, E. J. Gleason and S. W. L’Hernault, unpublished).
The spe-42 gene encodes a seven pass transmembrane protein, and two SPE-42 homologs are evident in all multicellular animals with a complete genome sequence, including C. elegans. In humans, one of these homologs has a splice form expressed in testes, but the precise function of SPE-42 or any of its homologs is not yet known (Kroft et al., 2005).
Spermatozoa derived from any of the seven mutants in this class have no detectable motility defects, and they make contact with oocytes in the spermatheca. Male-derived spermatozoa from five of these mutants (fer-14, spe-9, spe-13, spe-41/trp-3 and spe-42) render recipient, formerly self-fertile, hermaphrodites sterile after mating; such hermaphrodites cease laying embryos and begin to lay unfertilized oocytes (Singson et al., 1999; Xu and Sternberg, 2003). This sterility reflects the fact that these mutant, male-derived spermatozoa can out-compete and functionally displace endogenous, fertilization-competent hermaphrodite spermatozoa in the spermatheca (as in Figure 5C). The consequence of this displacement is that oocytes only contact fertilization defective spermatozoa during the narrow temporal window when they are competent for fertilization.
SPE-41 (Xu and Sternberg, 2003), SPE-9 (Zannoni et al., 2003) and SPE-38 (Chatterjee et al., 2005) are all plasma membrane proteins in spermatozoa. SPE-9 is also found in the plasma membrane of spermatids, but SPE-41 and SPE-38 are found in the MOs and become plasma membrane proteins when the MOs fuse during spermiogenesis. This observation places the SPE-41 TRP channel function on the cell surface where it could participate in calcium fluxes related to gamete fusion during fertilization. While SPE-41 is distributed on the plasma membrane of both the cell body and the pseudopod, SPE-9 and SPE-38 localize to the pseudopodial plasma membrane of spermatozoa (Figure 5C). These data indicate that there are at least two ways for plasma membrane proteins required for fertilization to reach the spermatozoan cell surface. Additional proteins important for oocyte recognition, adhesion and/or fusion are likely to be encoded by spe-13 and spe-36 and other sperm-expressed genes that remain to be discovered.
One mutant (spe-11) forms spermatozoa that are competent to fertilize oocytes, but embryogenesis never begins properly and the defective embryo always dies (Browning and Strome, 1996; Hill et al., 1989; L'Hernault et al., 1988). After a wild type oocyte is fertilized by a spe-11 spermatozoon, maternal meiosis is not usually completed properly and a defective eggshell forms. While mitosis is observed in oocytes fertilized by a spe-11 sperm, the spindle is not positioned correctly and cytokinesis does not usually occur. The typical end result is that multiple nuclei share a common cytoplasm in these defective embryos (Figure 5; Hill et al., 1989). Expression of the spe-11 gene normally occurs only during spermatogenesis, and the SPE-11 protein has no clear homologs outside nematodes (Browning and Strome, 1996). Ultrastructural examination of spe-11 mutant spermatids reveals that they have defects in perinuclear material surrounding the nucleus (Hill et al., 1989), which is where the SPE-11 protein localizes in wild type spermatids (Browning and Strome, 1996). This sperm-derived material is apparently required for some as yet unknown aspect of early embryogenesis. However, it does not have to be delivered via the sperm because transgenic expression in the oocyte is sufficient to allow embryos that have been fertilized with a spe-11 spermatozoon to survive (Browning and Strome, 1996). Other work has shown that the C. elegans sperm-derived nucleus (Sadler and Shakes, 2000) and centriole (O'Connell, 2002; O'Connell et al., 2001) are both required for embryogenesis. However, SPE-11 is the only known C. elegans protein that is both required for embryogenesis and normally has a sperm-specific expression pattern.
Progress in the study of C. elegans spermatogenesis has accelerated in recent years as the molecular identities of many of the involved genes have been discovered. The earliest stages of spermatogenesis employ genes (cpb-1, ife-1, puf-8, spe-39 and wee-1.3) that are not exclusively expressed during spermatogenesis. If genes exist that regulate translational control or meiosis, but commence expression after spermatogenesis has been initiated, they remain to be discovered. A partial picture of the function of the FB-MO has emerged, but much work remains to be done. The earliest stages of FB-MO morphogenesis are presumably controlled through the vesicular trafficking pathway. These components are likely to be expressed outside the testes (as is spe-39) and probably will require different types of mutant screens and/or RNAi studies to be identified. Although the genetic control of hermaphrodite spermiogenesis is becoming clearer, none of the genes that participate in the predicted male spermiogenesis pathway have been identified. Mutants with specific defects in male spermiogenesis are likely obtainable, but existing screening methods that rely on recovering self-sterile hermaphrodites will not allow identification of such mutants; new screens will need to be designed for this purpose. There has been much recent progress in identifying and analyzing the sperm-expressed genes that participate in fertilization. All five of the cloned genes that are important for fertilization encode transmembrane proteins. How these transmembrane proteins organize to interact with the egg during fertilization remains to be determined. The spe-11 mutant reveals that sperm play a crucial role in the delivery of components to the oocyte that allow it to progress through embryogenesis normally. It will be interesting to learn if there are other proteins required for embryogenesis that must be delivered by the sperm during fertilization.
I thank Sam Ward, Andrew Singson and members of the L’Herrnault lab for valuable discussion. Work in my laboratory has been supported by grants from the NIH (GM040697) and NSF (IBN-0131532).
Achanzar, W.E., and Ward, S. (1997). A nematode gene required for sperm vesicle fusion. J. Cell Sci. 110, 1073–1081. Abstract
Amiri, A., Keiper, B.D., Kawasaki, I., Fan, Y., Kohara, Y., Rhoads, R.E., and Strome, S. (2001). An isoform of eIF4E is a component of germ granules and is required for spermatogenesis in C. elegans. Development 128, 3899–3912. Abstract
Arduengo, P.M., Appleberry, O.K., Chuang, P., and L'Hernault, S.W. (1998). The presenilin protein family member SPE-4 localizes to an ER/Golgi derived organelle and is required for proper cytoplasmic partitioning during Caenorhabditis elegans spermatogenesis. J. Cell. Sci. 111, 3645–3654. Abstract
Bashir, R., Britton, S., Strachan, T., Keers, S., Vafiadaki, E., Lako, M., Richard, I., Marchand, S., Bourg, N., Argov, Z., et al. (1998). A gene related to Caenorhabditis elegans spermatogenesis factor fer-1 is mutated in limb-girdle muscular dystrophy type 2B. Nat. Genet. 20, 37–42. Abstract Article
Boxem, M., Srinivasan, D.G., and van den Heuvel, S. (1999). The Caenorhabditis elegans gene ncc-1 encodes a cdc2-related kinase required for M phase in meiotic and mitotic cell divisions, but not for S phase. Development 126, 2227–2239 Abstract
Browning, H., and Strome, S. (1996). A sperm-supplied factor required for embryogenesis in C. elegans. Development 122, 391–404. Abstract
Chatterjee, I., Richmond, A., Putiri, E., Shakes, D.C., and Singson, A. (2005). The Caenorhabditis elegans spe-38 gene encodes a novel four-pass integral membrane protein required for sperm function at fertilization. Development 132, 2795–2808. Abstract Article
Gleason, E.J., Lindsey, W.C., Kroft, T.L., Singson, A.W., and L'hernault, S.W. (2006). spe-10 encodes a DHHC-CRD zinc-finger membrane protein required for endoplasmic reticulum/Golgi membrane morphogenesis during Caenorhabditis elegans spermatogenesis. Genetics 172, 145–158. Abstract Article
Hemler, M.E. (2003). Tetraspanin proteins mediate cellular penetration, invasion, and fusion events and define a novel type of membrane microdomain. Annu. Rev. Cell Dev. Biol. 19, 397–422. Abstract Article
Hill, D.P., Shakes, D.C., Ward, S., and Strome, S. (1989). A sperm-supplied product essential for initiation of normal embryogenesis in Caenorhabditis elegans is encoded by the paternal-effect embryonic-lethal gene, spe-11. Dev. Biol. 136, 154–166. Abstract Article
Kelleher, J.F., Mandell, M.A., Moulder, G., Hill, K.L., L'Hernault, S.W., Barstead, R., and Titus, M.A. (2000). Myosin VI is required for asymmetric segregation of cellular components during C. elegans spermatogenesis. Curr. Biol. 10, 1489–1496. Abstract Article
Kimble, J., and Ward, S. (1988). Germ-Line Development and Fertilization. In The Nematode Caenorhabditis elegans, W.B. Wood, ed. (Cold Spring Harbor, Cold Spring Harbor Laboratory Press), pp. 191–213.
Klass, M.R., and Hirsh, D. (1981). Sperm isolation and biochemical analysis of the major sperm protein from Caenorhabditis elegans. Dev. Biol. 84, 299–312. Article
Kroft, T.L., Gleason, E.J., and L'Hernault, S.W. (2005). The spe-42 gene is required for sperm-egg interactions during C. elegans fertilization and encodes a sperm-specific transmembrane protein. Dev. Biol. 286, 169–181. Abstract Article
Lamitina, S.T., and L'Hernault, S.W. (2002). Dominant mutations in the Caenorhabditis elegans Myt1 ortholog wee-1.3 reveal a novel domain that controls M-phase entry during spermatogenesis. Development 129, 5009–5018. Abstract
LaMunyon, C.W., and Ward, S. (1994). Assessing the viability of mutant and manipulated sperm by artificial insemination of Caenorhabditis elegans. Genetics 138, 689–692. Abstract
L'Hernault, S.W. (1997). Male germ line. In C. elegans II, D. Riddle, R. Blumenthal, B.J. Meyer, and J. Priess, eds. (Cold Spring Harbor, NY: Cold Spring Harbor Press), pp. 271–294.
L'Hernault, S.W., and Arduengo, P.M. (1992). Mutation of a putative sperm membrane protein in Caenorhabditis elegans prevents sperm differentiation but not its associated meiotic divisions. J. Cell Biol. 119, 55–68. Abstract Article
L'Hernault, S.W., Shakes, D.C., and Ward, S. (1988). Developmental genetics of chromosome I spermatogenesis-defective mutants in the nematode Caenorhabditis elegans. Genetics 120, 435–452. Abstract
Lundgren, K., Walworth, N., Booher, R., Dembski, M., Kirschner, M., and Beach, D. (1991). mik1 and wee1 cooperate in the inhibitory tyrosine phosphorylation of cdc2. Cell 64, 1111–1122. Abstract Article
L'Hernault, S.W., and Singson, A.W. (2000). Developmental Genetics of Spermatogenesis in the Nematode Caenorhabditis elegans. In The Testes: From Stem Cell to Sperm Function, Serono Symposium USA, E. Goldberg, ed. (New York, Springer-Verlag), pp. 109–119.
Machaca, K., DeFelice, L.J., and L'Hernault, S.W. (1996). A novel chloride channel localizes to Caenorhabditis elegans spermatids and chloride channel blockers induce spermatid differentiation. Dev. Biol. 176, 1–16. Abstract Article
Machaca, K., and L'Hernault, S.W. (1997). The Caenorhabditis elegans spe-5 gene is required for morphogenesis of a sperm-specific organelle and is associated with an inherent cold-sensitive phenotype. Genetics 146, 567–581. Abstract
Nance, J., Davis, E.B., and Ward, S. (2000). spe-29 encodes a small predicted membrane protein required for the initiation of sperm activation in Caenorhabditis elegans. Genetics 156, 1623–1633. Abstract
O'Connell, K.F., Caron, C., Kopish, K.R., Hurd, D.D., Kemphues, K.J., Li, Y., and White, J.G. (2001). The C. elegans zyg-1 gene encodes a regulator of centrosome duplication with distinct maternal and paternal roles in the embryo. Cell 105, 547–558. Abstract Article
Putiri, E., Zannoni, S., Kadandale, P., and Singson, A. (2004). Functional domains and temperature-sensitive mutations in SPE-9, an EGF repeat-containing protein required for fertility in Caenorhabditis elegans. Dev. Biol. 272, 448–459. Abstract Article
Roberts, T.M., Pavalko, F.M., and Ward, S. (1986). Membrane and cytoplasmic proteins are transported in the same organelle complex during nematode spermatogenesis. J. Cell Biol. 102, 1787–1796. Abstract Article
Roberts, T.M., and Ward, S. (1982). Centripetal flow of pseudopodial surface components could propel the amoeboid movement of Caenorhabditis elegans spermatozoa. J. Cell Biol. 92, 132–138. Abstract Article
Sadler, P.L., and Shakes, D.C. (2000). Anucleate Caenorhabditis elegans sperm can crawl, fertilize oocytes and direct anterior-posterior polarization of the 1-cell embryo. Development 127, 355–366. Abstract
Shakes, D.C. (1988) A genetic and pharmacological analysis of spermatogenesis in the nematode, Caenorhabditis elegans.Ph.D. Thesis, Johns Hopkins University, Baltimore.
Shakes, D.C., and Ward, S. (1989). Mutations that disrupt the morphogenesis and localization of a sperm-specific organelle in Caenorhabditis elegans. Dev. Biol. 134, 307–316. Article
Singson, A., Hill, K.L., and L'Hernault, S.W. (1999). Sperm competition in the absence of fertilization in Caenorhabditis elegans. Genetics 152, 201–208. Abstract
Subramaniam, K., and Seydoux, G. (1999). nos-1 and nos-2, two genes related to Drosophila nanos, regulate primordial germ cell development and survival in Caenorhabditis elegans. Development 126, 4861–4871. Abstract
Subramaniam, K., and Seydoux, G. (2003). Dedifferentiation of primary spermatocytes into germ cell tumors in C. elegans lacking the pumilio-like protein PUF-8. Curr. Biol. 13, 134–139. Abstract Article
Varkey, J.P., Jansma, P.L., Minniti, A.N., and Ward, S. (1993). The Caenorhabditis elegans spe-6 gene is required for major sperm protein assembly and shows second site non-complementation with an unlinked deficiency. Genetics 133, 79–86. Abstract
Varkey, J.P., Muhlrad, P.J., Minniti, A.N., Do, B., and Ward, S. (1995). The Caenorhabditis elegans spe-26 gene is necessary to form spermatids and encodes a protein similar to the actin-associated proteins kelch and scruin. Genes Dev. 9, 1074–1086. Abstract
Ward, S. (1986). The asymmetric localization of gene products during the development of Caenorhabditis elegans spermatozoa. In Gametogenesis and the Early Embryo, J. Gall, ed. (New York: A.R. Liss), pp. 55–75.
Ward, S., and Carrel, J.S. (1979). Fertilization and sperm competition in the nematode Caenorhabditis elegans. Dev. Biol. 73, 304–321. Abstract
Zannoni, S., L'Hernault, S.W., and Singson, A.W. (2003). Dynamic localization of SPE-9 in sperm: a protein required for sperm-oocyte interactions in Caenorhabditis elegans. BMC Dev. Biol. 3, (6 page article). Abstract Article
*Edited by Judith Kimble and Susan Strome. Last revised March 14, 2005. Published February 20, 2006. This chapter should be cited as: L'Hernault, S.W. Spermatogenesis (February 20, 2006), WormBook, ed. The C. elegans Research Community, WormBook, doi/10.1895/wormbook.1.85.1, http://www.wormbook.org.
Copyright: © 2006 S.W. L'Hernault. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


Have you ever wondered how to represent the links between nature and people in a simple way to facilitate decision making? A diverse group of experts share their tips in addressing this very challenge and suggest possible ingredients of such a representation. The hope is that this 'recipe' will help the work of the top new nature platform (IPBES) in relating biodiversity and its benefits to human well-being, sustainability and conservation.
These simple representations, or the so called conceptual framework, provide a shared language and a common set of relationships and definitions. This week experts presented their views to more than 100 governments gathered in Bonn for the first meeting of the IPBES Plenary, the highest governing body of the Platform.
A conceptual framework for IPBES can help to ensure a coherent and consistent approach across the four functions of the Platform - knowledge generation, assessment, policy support and capacity building. It could also clarify linkages and integration between them.
"Indeed, a conceptual framework will be a common approach to discharging each of these envisaged functions and for guiding and framing the implementation of its programme of work, in a multiple knowledge, multiple discipline and multiple scale manner, “ says Salvatore Arico of UNESCO. “It will provide a critical lens through which to tackle the complex set of issues IPBES will focus on.”
Following the expert suggestions, the governments are currently considering the way forward in developing such a conceptual framework for IPBES. The possible ‘ingredients’ include biodiversity, ecosystem goods and services, and their benefits for human well-being. There are also institutions, decisions and drivers together with properties and processes that occur at different scales and affect the interaction between the components.
“While unpacking these concepts it is important to keep in mind what appeals to different disciplines – capital is appealing to economists, human well-being to sociologists, and biodiversity to ecologists. We can achieve common understanding by doing so in a group,” suggests Georgina Mace, Professor at the University College London.
“By fostering bridges between disciplinary, interdisciplinary, and local knowledge about the interdependence of human well-being, biodiversity and ecosystem services, IPBES will spur innovative ways and research to tackle problems of local, regional, and global societal relevance. A conceptual framework will be central to this goal,” says Eduardo Brondizio, Professor at the Indiana University Bloomington and Université Sorbonne Nouvelle - Paris 3.
Thomas Brooks, Head of Science and Knowledge at IUCN emphasizes that “IPBES will harness outstanding scientific input, but its purpose is far from academic. Rather, it will support policy and practice in halting our current, disastrous loss of biodiversity and ecosystem services”.
“IUCN supports the suggestions of the expert group and welcomes the interest of governments in developing a conceptual framework for IPBES,” adds Cyrie Sendashonga, Global Director of Policy and Programmes at IUCN. “However we also suggest a number of improvements in the proposed ‘cooking steps’. For example, as much alignment as possible between the IPBES conceptual framework and the set of indicators used to measure progress in achieving the Aichi Targets is critical. It would identify the gaps and best support appropriate policy implementation and communication at various levels in halting the loss of biodiversity.”
The work of informal group of experts in identifying the ingredients of a possible conceptual framework and the outcome of their discussions were produced with the support of UNESCO, DIVERSITAS, IHDP, IUCN, Ministry of the Environment of Japan, Gordon and Betty Moore Foundation and UNEP.
- Summary of expert discussions: brochure "How to bake a conceptual framework for IPBES" (download the interactive version or access the print version);
- Full expert report: Main issues relating to the development of a conceptual framework for IPBES (IPBES/1/INF/9).


What do animals actually do in poor environments? Compete more or facilitate for each other? Isabel Barrio and her co-workers studied this in herbivores in the harsh alpine tundra, resulting in teh new Early View paper: Extending the stress-gradient hypothesis – is competition among animals less common in harsh environments? Here’s Isabel’s own background story to the study:
Many summers in the alpine tundra have inspired our study. Alpine environments are strongly seasonal and are characterized by harsh environmental conditions, but they can host a surprisingly large numbers of herbivores. Annual net primary productivity in alpine ecosystems is generally low, so negative interactions (i.e. competition for resources) are usually expected to dominate among herbivores. However, the stress gradient hypothesis (SGH) developed by plant ecologists leads to the opposite prediction; namely, that in stressful environments, positive interactions (i.e. facilitation) would be the most common type of interaction. But, are plants and animals so different in this respect? Although facilitation among animals has been described in some highly productive ecosystems, such as tropical savannas, no theoretical framework exists that relates the balance between positive and negative interactions along environmental gradients. In our paper “Extending the stress-gradient hypothesis – is competition among animals less common in harsh environments?” we evaluate how the stress-gradient hypothesis might apply to terrestrial herbivores.
We considered alpine herbivores for developing our framework, because most examples of the SGH come from alpine plant communities. According to the SGH, and given that stress for herbivorous animals in these environments can be equated to inverse productivity gradients, we wondered if positive interactions would prevail in alpine environments because of their low productivity. We reviewed the available examples on interactions among alpine herbivores and found very few experimental studies on this topic. Interestingly, they were biased towards reporting on significant competitive interactions. Despite this bias, we found no evidence of competition being the dominant interaction type in low productivity alpine environments, which directly challenges the dominant view among animal ecologists. Although we did not find strong support for the SGH either, we argue that specifically designed experiments can help investigate the applicability of this framework to terrestrial vertebrates. Extending the SGH through clear predictions can provide a solid starting point for understanding the role of positive and negative interactions in structuring terrestrial animal communities.


Invest in educational equity to show students how much you care for them | engage2learn
Classrooms are sacred places for our youth. This is where the foundational skills needed to graduate and reach their personal goals are established. Students who have solid foundations easily stand out in a crowd. Their Life Ready Skills speak loudly and clearly about the experiences in their learning environments. Equity plays a major role in student success. Access to educational resources and lack of cultural identification are just a few of the issues with equity and education.
It is evident when these experiences are lacking in students from Life Ready Skills to academic gaps that are often difficult to fill as they move through their educational journey. Investing in educational equity is crucial to student success. It demonstrates to students how much we value and care about them through acknowledgment of who they are, from where they come, and where they are headed. As educators, we must work tirelessly to ensure all children in our care are well equipped for what life may hold for them, be it college, the workforce, or military service.As educators, we must work tirelessly to ensure all children in our care are well equipped for what life may hold for them, be it college, the workforce, or military service. Click To Tweet
One of the biggest ways to positively impact equity is through campus and classroom environments created by educators. The environment or space within students and teacher experience learning speaks volumes and has an everlasting effect. A quote by Haim Ginott, renowned educator and child psychologist/psychotherapist, helps drive home the understanding of how an environment can be shaped by its leaders. “I’ve come to a frightening conclusion that I am the decisive element in the classroom. It’s my personal approach that creates the climate.”
The classroom climate is often described as a culture by those in the field. Classroom culture is an essential tool that teachers can use to nurture skills like Critical Thinking, Autonomy, and Collaboration. It can also affect the results of Best Practices implemented by teachers within the classroom such as Assessment and Formative Feedback, Growth Mindset, and Differentiation and Scaffolding.
When an investment is made to understand students’ backgrounds, powerful connections and relationships are built and changes the climate in which a child has to develop. This loving environment can have lasting impacts and aid in increased student success. Below are a few ways to show some love and support to the students you serve. Choose something to establish as a norm on your campus or in your classroom. With minor changes in educational practice, we can impact students in a substantial way!
- Choose cultural text that relates to a student’s background,
- Use background music to teach acceptance (switch genres to expose students to different sounds),
- Allow students to request and receive help in a one-on-one or small group setting (e2L calls them workshops),
- Allow a student to lead peers in learning a skill or skill set (i.e. use of technology app),
- Create an incentive program where a LIFE ready skill is awarded (Autonomy, Growth Mindset, etc.), and
- Allow students to show mastery of a concept outside of an exam or paper (Poem, Speech, Rap, or Video).


|Byzantine painting of Adam Naming the Animals.|
Monday, June 1, 2015
Dinosaurs and Dragons - VBS by Pastor Ronnie Koch
Many children are enthralled with Dinosaurs and Dragons. Ancient bones that have been dug up seem to tell stories of great beasts that once roamed the land, sea and sky. In our Vacation Bible School today we talked about three important lessons the Bible has about Dinosaurs and Dragons.
1. God Created All Creatures.
Genesis 1: 24 And God said, “Let the earth bring forth living creatures according to their kinds—livestock and creeping things and beasts of the earth according to their kinds.” And it was so.
There are no beasts or monsters that are outside of God’s creation or outside of God’s control.
2. God Cared for All Creatures.
Especially in the days of Noah God protected them from the flood.
Genesis 7:14-16 every beast, according to its kind, and all the livestock according to their kinds, and every creeping thing that creeps on the earth, according to its kind, and every bird, according to its kind, every winged creature. 15 They went into the ark with Noah, two and two of all flesh in which there was the breath of life. 16 And those that entered, male and female of all flesh, went in as God had commanded him. And the LORD shut him in.
3. All Creatures Praise God.
Dinosaurs and Dragons teach us how powerful and wise our Creator is.
Psalm 148:7 & 10 Praise the LORD from the earth,
you great sea creatures and all deeps,
Beasts and all livestock,
creeping things and flying birds


"Sustainable Lifestyle Website" (Neta Nakash, Raleigh McCoy)
A major contributing factor to unsustainable actions is a lack of information. Most people don't have the express intention of living unsustainably; rather, they do not know the effects of their actions or are unfamiliar with more sustinable alternatives. This website seeks to remedy this problem amongst IES students. The IES sustainability website offers information specifically targeted at IES students living in Barcelona to help them amend their habits to live more sustainably. For simplicity, we have chosen to target three areas of sustainability: food, transportation, and general habits. Each area has its own page with information about sustainable habits, as well as links to outside web pages and pictures that communicate the information quickly and in an interesting way. Previous students designed a welcome page, a forum, resources about restaurants and grocery stores, and an item sharing registry. These resources will also be available on the same website.
1. What is the action
We have added relevant sections to a Sustainable Lifestyle Website under the categories of Food, General Habits, and Transportation. The suggestions on the website provide students with the means of being environmentally friendly and sustainable while in Barcelona, and hopefully they continue to do so in the future. This website was created by students in 2011 through sc.seeds4c.org and we have simply added these relevent pages under the 2013 tab at the top left corner of the webpage. IES students were notified about the website once we completed these three webpages.
1.1. Why this action makes things more sustainable?
This action is improving the sustainability of IES Abroad Barcelona by educating students about the concept of becoming sustainable, as well as giving them real world tools needed to be more sustainable. Many times, the root of the problem is not students making conscious decisions that harm the environment, but rather, a lack of knowledge about the effects of their actions and of alternatives. A simple lack of information, when aggregated over hundreds of IES students, creates an urgent threat to sustainability. Examples of positive changes to habits include accessing more sustainable modes of transport (walking, biking, and public transit), using products that are more sustainable, and reducing water consumption. The website seeks to change the habits of students in the long term, not just for their semester abroad, with the ultimate goal of long term reduction of waste, water use, and ecological footprint. Lastly, by publishing this information as a webpage we are eliminating paper or other waste, thus educating students in the most sustainable way possible.
1.2. "Cradle to Cradle" design
This design is cradle to cradle ready since it is all online, thus there is no waste. The webpage was updating using an already existing computer so no new waste was created. Electricity was needed to charge the computer. But ultimately there is no paper trail in this project or new waste! We chose to communicate this information electornically rather than through paper resources like fliers, handouts, brochures, etc. because the information will be available in perpetuity and endlessly distributable. This action seeks to be not just eco-efficient, but eco-effective by not advocating for quick fixes, but real solutions to unsustainable habits. For example, rather then suggesting that students use energy efficient appliances, we recommend that they simply do not rely on these appliances at all.
1.3. Similar actions from previous semesters
This action was started in 2011 and has information about vegetarian, vegan, and organic restaurants, as well as information about renting bikes through IES. Other actions from previous semesters that are similar to this one are listed below:
Courses:_:From 2011 Spring - Where to EAT in BCN Blog (Natalia - Liz - Ali - Jake)
Courses:_:From 2012 Fall - IES Environmentally Friendly Welcome Kit (Sean - Anthony - Jose)
1.3.1. Why This or a Similar Action Didn't Succeed in Previous Semesters?
The website was created successfully and presents the information in a clear, approriate manner. It is unclear if the website was advertised when it was implemented. This website was not advertised to us this semester so in this sense it was unsuccessful as a continued effort. Publishing a website and advertising through the means of the internet requires that students have access to the internet, which can pose a problem. However, the IES center has free WiFi for students as well as computers available to students, so any IES student has the ability to access the website.
October 4: Begin work on website, including researching information about sustainability pertaining to BCN
October 14: Website is ready for publishing
October 14: Wrote blurb for email to be sent to all students at IES
Octotober 14: Email website URL to IES Abroad webmaster. Request the addition of a link to our page on the IES website as soon as possible.
October 14: Email website URL to staff member involved with the student life department. Ask them to email the URL to all IES students along with a brief blurb that we will write describing the content available. Also, ask the department to publicize the website in future semesters via email, using the same blurb.
October 15: IES Students recieve email about existing website
2.1. The action
We updated the existing website to include three new pages with information about sustainable habits, sustainable transportation, and sustainable food choices. The new pages can be found under the tab called 2013 in the top left corner.
|Time Consuming||We decided to focus on implementing three categories, (Transportation, Habits, and Food) and hope that next semester students will continue to develop the website to provide even more resources|
|Requires basic HTML, or web design knowledge||We have asked for assistance we needed and create basic web pages that display the intended information and content rather then focusing on the design aspects|
|Dependent on IES staff to publicize||We did not have the resources available to reach a wide audience of IES students, so we had to ask IES staff member Jane Ewart for help. She was very accommodating, but it would have been better for us if we could have done it ourselves.|
|Having to deal with the existing IES GO Green website||Since we had to use their format and styling, we had to adapt to their format for presenting the information. This was a compromise we had to make and thus that was the solution.|
2.3. How will this action be sustained when you are not here?
IES will need to advertise about the website by promoting it during orientation, sending email reminders to the student body, and featuring a link on the IES home page. Select students in the following semester's sustainability class can choose to maintain and update the website as well and aid IES in the advertising of the website. The beauty of a website as opposed to other forms is that it does not degrade the way physical information will. This is not a poster that can be taken down, or a brochure that can be thrown away. Also, the concepts advertized on our page will not become obsolete for a long time - for instance, taking short showers will always be more sustainable than taking long showers. Therefore, the content does not need to be edited very often. The one thing that should be curated carefully is the links to external pages, making sure the links stay active. If the link URL changes, the link will no longer work. However, our site does not rely heavily on links; most of the information is unique text that is saved on the website's server.
3. Document format
No external documents were created for this project, simply the website itself.
5. Other References
The pictures used on the webpages come from the following URLs:
Most of the information provided in webpages comes from previous sustainability and environmental science courses.
Email to Jane Ewart regarding advertizing of website:
Is it possible to post this link to the IES Barcelona homepage and social media accounts? We really want to get the word out about this website and reach the widest audience possible. Below is the text of the email. Thank you so much for your help!
Subject- Small Changes, Big Results: Be Sustainable
Curious about sustainability while abroad in Barcelona? Your fellow students have created web pages with resources that will not only help save the planet but also your money. You can find information about sustainable habits, transportation, and food suggestions.
Here is the link, scroll over the tab that says 2013 for the newest information
The website host, sustainability.seeds4c.org allowed this website to be possible.
Xavi helped with formatting our specific web pages.
Olga provided us with necessary instructions on how to edit the website.
6.2. Students involved in this action
Neta Nakash came up with the idea to implement the Sustainable Lifestyle Website and was the official leader, outlining the necessary tasks for the project. Raleigh wrote the email blurb and sent the instructions to Jane. Neta has prior experience in HTML formatting so she was in charge of posting the researched and gathered information to the webpages as well as the images. Both students researched infomation to be put up on the website. Both students worked together on the IOA plan and met together to add content to the website.


* Any prices shown are subject to availability and market conditions.
The first European porcelain was successfully developed by Johann Friedrich Bottger, an alchemist in the service of August II in the early eighteenth century. A factory at Dresden was established in 1710 and, though technical issues blighted production in the first years, developments and experimentation continued and a consistent and high-quality output was established. Initial designs, largely owing to the technical brilliance and knowledge of the artists Samuel Stotzel (1685-1737) and Johann Gregorius Horoldt (1696-1775), took their inspiration from the East, with Chinoiserie representing a cultural fascination with the relatively unknown lands of China and Japan. The initial drive to produce porcelain in Europe was in order to source a cheaper, native alternative to export Chinese wares, which, though popular, were exceedingly expensive to ship to Europe and, especially given the porcelain-mania of Augusts, put severe strain on national coffers. Over time Meissen designs became more stylised and experimental, diverting from Asian models and including European landscape scenes.
Meissen's trademark crossed sword symbol first appeared in 1723-24, and were initially applied in overglaze enamel colour along with the initials KPM. After 1724, the crossed swords were applied alone; a tradition which continues to this day. A wide stylistic variety of this symbol is seen across Meissen wares, but cannot be used to accurately date pieces. Certain impressed marks began to appear on pieces in around 1735, and much work has been done in recent years to attribute these marks, known as 'formers marks' to specific potters. These formers marks were replaced by impressed numbers in 1739, and are generally found on the base, near the foot rim. Numbers or marks in gilt represent the 'guilder's mark' and other letters and numerals can refer to individual painters.
As the secret of 'true' porcelain spread across Europe during the eighteenth century, local production centres produced their own interpretations of the popular oriental designs. Soft-pastse porcelain manufactories already established in France, England, Italy and Spain turned their attention to hard-paste porcelain.
Abraham L. den Balluwen. 2000. Meissen Porcelain in the Rijksmuseum (Amsterdam, Waanders)
Ulrich Pietsche. 2011. Early Meissen Porcelain, The Wark Collection (London, Giles)
Jeffrey Munger. 2018. European Porcelain in the Metropolitan Museum of Art (New Haven, Yale UP)


You know when your kid’s not feeling well physically, but would you know what to look for if he or she had a mental illness?
It’s a growing problem in the United States, according to a recent report by the Centers for Disease Control and Prevention, which found that one out of five children in the U.S. has been diagnosed with a mental disorder.
Learn what the signs are, which disorders are overly diagnosed, and how you can find help.
What to look for
“The signs look different than adults,” said Dr. Elizabeth Waterman, a clinical psychologist at Morningside Recovery Center in Newport Beach, Cali. For example, depression often shows up as irritability, agitation and bouts of crying.
Teens with depression usually withdraw and become isolated from their friends, and they may have conflict with parents and authority. “It needs to be present significantly longer than for adults for it to be considered depression,” Waterman said.
Kids with anxiety usually worry a lot, fearing sleep, being separated or being alone, and getting injured.
Other signs may include:
• Hyperactivity: difficulty concentrating, completing homework, sitting still, and following rules
• Changes at school: poor grades, complaints of stomachaches and headaches, making excuses not to go to school, social and behavioral changes
• Loss of interest in regular extra-curricular activities
• Sleep changes: too much or not enough
• Eating and exercise: eating too much or not enough, exercising too much, taking laxatives, or binging or purging
• Increased mood swings, irritability, and anger
• Impulsivity: It’s normal for teens, but reckless driving, drinking, smoking, using drugs and sexual behaviors can be dangerous.
• Extreme or unexplained fear or sudden attachment
• Feelings of worthlessness, helplessness, hopelessness, and sadness
• Anxiety or panic attacks
• Destroying property, breaking the law, hurting animals, and hearing voices
• Talk about death, not wanting to live, and thoughts of suicide.
If you think your child may have a mental disorder, here’s what you should do.
Get a check-up
It’s important to make an appointment with your child’s pediatrician first to rule out a physical condition, an allergy, a learning disorder, or autism, which might look like a mental disorder, according to Diane Lang, an author, psychotherapist, and positive living expert.
Find a specialist
When getting an evaluation, instead of jumping to conclusions, focus on getting an accurate diagnosis or ruling one out. “It could easily be that it is a behavioral issue or a lack of parenting skills,” said Waterman, who added that a therapist or child psychologist can make a diagnosis, provide treatment or recommend family therapy or parenting skills training.
Know that some disorders are overly diagnosed
Attention deficit-hyperactivity disorder (ADHD) is the most common parent-reported diagnosis, according to the same CDC report. Yet both Waterman and Lang agree that ADHD is overly diagnosed, which is why it’s important to confirm the diagnosis with the pediatrician, psychologist or psychiatrist.
And some show up later
“(Schizophrenia and bipolar disorder) are being diagnosed in children far too often,” Waterman said. These two disorders also tend to show up later on in the teen years, so it’s rare that a young child would have it.
Don’t use labels
Avoid terms like ‘depression’ or ‘anxiety disorder,’ because they can be damaging to a child’s self esteem, Waterman said. Instead, talk about the symptoms as the problem and explain that your child is getting help so he or she doesn’t have to feel worried, for example.
Oftentimes, parents don’t really understand how the child is feeling or how to help them, which is why learning all you can about your child’s disorder is crucial. “If a parent gets educated on what the child’s going through, they can learn how to cope with it better themselves,” Lang said.
Sharing your experience with other parents who are going through the same thing can help you cope. Check with your child’s pediatrician or local hospital for information about local support groups.
There is hope
“Mental illness is treatable,” said Lang. Parents should feel confident that with professional help, their child can get better.
Julie Revelant is a health journalist and a consultant who provides content marketing and copywriting services for the healthcare industry. She's also a mom of two. Learn more about Julie at revelantwriting.com.


Learn the names of fruits and vegetables in English for children with toy velcro cutting food and Peppa Pig ESL, first we wash and cook lots of fun toy food fruits and vegetables. And then we learn the colours and names in english with nursery rhymes. Peppa Pig and Daddy Pig is very very hungry, so first we wash the velcro toy vegetables and then we cook them. Perfect Edutaintment video for toddlers, babies and pre-schoolers but also for people who want’s to learn English as a second language.
Mamma Kangaroo makes fun and exciting videos for kids of all ages, your kid can learn all about food and have a lot of fun while doing so with Mamma Kangaroo learning videos. You can also learn colours, shapes, and even the alphabet with Mamma Kangaroo’s fun videos for babies and toddlers. Come back weekly for more fun videos.


Recently voted “Teacher of the Year” of her Austin, TX campus, special teacher, Hannah Cash, uses Especially Education task boxes to build independence in her students with mild to moderate disabilities, and shares the quick and simple editable data collection system she developed to ensure student progress can easily be monitored by multiple adults.
One thing I knew I wanted to incorporate in my classroom this year was task boxes.
After being introduced to task boxes, I was impressed with the concept and knew it could change the structure of my class while also promoting student independence.
However, one thing I knew could potentially be an issue with task boxes was data collection. After a few months of trial and error, I believe I have developed a successful and streamlined data collection system.
Before I go into data collection, it is important to describe how task boxes changed my life as well as how I use them in my classroom. Task boxes are part of my academic rotations.
I typically have small group lessons at my table while students are working on task boxes at their desk with a Teaching Assistant sitting next to them.
Task boxes serve a different purpose for each student.
Currently, my students have a wide range of abilities. While some students with multiple impairments are working on mobility, other students are concentrating on multiplication. With my current students, I use task boxes for the following purposes:
- Building independence. For these students, my go-to task boxes are The Original Task Box Bundle.
- Generalizing objectives taught and extra practice. For these students, my go-to task boxes are Math Higher Level Task Boxes.
- Mobility (i.e. picking up an item and matching it to another item). For these students, my go-to task boxes are Basic Skills Task Boxes.
Since each task box provides a different purpose, I realized data collection would look different for each student. because I want students to understand the objective of the task box, and are able to complete it independently, the first thing I created was a data collection sheet to determine if students are completing tasks correctly.
The second data sheet I designed makes sure students are working towards completing the task- without worrying about accuracy.
It is important students become independent and begin a task box without needing prompting from teachers.
I am lucky to have a Teaching Assistant monitor my students while they are working on the task boxes.
During this time, the assistant collects data and help students if needed. However, there are plenty of times when TAs are pulled or out in inclusion and I have to collect the data. One thing I found helpful is getting everything set up in the morning.
I fill in all the task boxes given and any other information I can (such as the total number of activities in the task box).
This method helps data collection take only a few seconds to complete.
Since the school day is always so busy, I usually have the data sheets piled up at my table and will review them after school. I like to take some time at the end of the day to review and see what concepts my students are struggling with or what they are mastering.
This helps with understanding what I may need to reteach or if I feel that the students are ready to move to the next concept.
Another thing I like to do with the data collected is celebrate student achievement. One of my favorite things with data collection is being able to show the students the progress they have made. This gives students a chance to bask in their accomplishments.
I have included the data collection sheets I currently use and hope it’s something you can start to use in your classrooms, too!
Ever since I can remember, I’ve been drawn to people with special needs. It makes me happy to watch my students grow and progress with all their hard work. I truly believe I was put on this planet to work with these children.
If you’ve seen my posts recently, you may be thinking, “wow, Michaela sure has been posting a lot about her projects and activities! But why?”
Well, as a special education teacher in a self-contained classroom, I know how challenging it can be for my students to access the grade-level curriculum. Resources are limited and can require hours worth of accommodations and modifications.
The intention behind my TPT store is to provide teachers with adapted teaching materials that focus on the prerequisite skills needed to master grade-level standards and provide engaging, hands-on activities that make learning exciting and appropriate.


The world’s water resources are rapidly running dry creating a global crisis for every living being on the planet. 1 billion - nearly 1/6th of the world’s population - are already facing water shortages on a daily basis.
A report by the United Nations states that by 2030 almost half the global population will be living in water stressed areas. At the current rate, the hugely populated area of Beijing will have exhausted its water supplies by 2030. In the United States, the Colorado River supplies tens of millions of people and millions of acres of farmland. Drought could cause shortages to a massive number of people dependent on this water source.
Scientists foresee that there will be an increasing number of wildfires as the results of climate change intensify.
- In 2008 alone, California’s fires devastated 380,310 acres of land.
- In 2007, more than 200 wildfires occurred in South Eastern Europe.
- In 2009, 28 districts in Nepal experienced wildfires in the pre-monsoon period; this is unprecedented and a direct effect of global warming.
- A decade of drought in Australia has greatly increased the intensity of bush fires.
Fires release more carbon into the atmosphere, and the loss of trees results in less carbon being sequestered. In the coming years, wild fires are predicted to spread to previously fire-free regions of the world due to climate change.
One of the largest contributors to fire pollution exacerbating global warming is the tens of thousands of fires, many in the Amazon region, burnt annually to clear forest for livestock grazing and livestock feed.
Drought is one of the major problems our world is facing and is set to escalate dramatically in the coming years if present trends continue.
- In 2009, China’s worst drought in five decades caused massive loss of vital crops in 12 provinces.
- Aquifers under Beijing, Bangkok, Delhi and many more locations are drying up.
- The world’s major rivers such as the Ganges, Jordan, Nile and Yangtze are all suffering as climate change intensifies.
- Since 2003, Australia has been experiencing drought that has now led to heavy water restrictions and massive losses for thousands of farmers.
- Southern Madagascar has experienced three years of crop failures in the past 5 years, seeing an increase of malnutrition and death in children.
- Due to drought, 2009 saw Argentina’s smallest wheat crop for 100 years, putting strains on global supplies.
It is predicted that most parts of the United States will soon be experiencing national water shortages. Even in Europe as many as 120 million people have little access to clean water.


Say goodbye to mystery meat - and all other types of meat - at public school cafeterias that are embracing the Meatless Monday trend.
A vegetarian diet isn't one embraced by the majority of Americans today. In fact, according to the Johns Hopkins Center for a Livable Future, most Americans exceed the daily amount of recommended protein by a significant amount, with much of it coming from meat and animal products every day. However, many public schools are hoping to change that trend by introducing "Meatless Mondays" to their students and faculty.
According to an article last year by U.S. News and World Report, numerous schools across the country have begun offering vegetarian selections to students on a daily basis. These choices were provided in addition to meat entrees, giving students both diet options. However, Meatless Mondays are a new concept that was recently introduced by Baltimore City Public Schools and is quickly spreading across the nation as other school districts are hopping onboard the vegetarian bandwagon.
Going Meatless in Baltimore
A report in the Washington Post stated the Baltimore City Public Schools launched their Meatless Mondays campaign in October of last year. Instead of the usual fare of hamburgers, pizza and "pigs-in-a-blanket," the schools are providing students with healthy, meatless options like cheese sandwiches, cheese lasagna and mixed vegetable bowls.
Melissa Mahoney, a chef and dietician with the Baltimore school district, said the idea started as an element of a themed-approach to school lunch menus. When the district realized that Meatless Mondays were a part of a national campaign backed by hospitals and animal-rights activists, they began working with the larger organization to develop their plan.
Benefits of Meatless Meals
The benefits the school district hopes to achieve through this initiative include:
· Introduction of a variety of fruits and vegetables to students and staff
· Improvement of the personal health of students and faculty
· Reduction of the district's carbon footprint
The ultimate goal of the program is to reduce meat consumption by 15%. However, the idea has not been embraced by everyone.
Pros and Cons
There are many advocates of the Meatless Mondays program, including former Beatle Paul McCartney, the Johns Hopkins Center for a Livable Future and animal-rights activists. However, not everyone is thrilled with the idea, particularly the American Meat Institute, the National Cattlemen's Beef Association, the National Pork Board and the Farm Bureau. These organizations have launched their own campaign to advocate for meat consumption and urged school districts like Baltimore to reconsider the Meatless Mondays program.
The Spreading Phenomenon
Despite opposition, the Meatless Monday program is continuing in Baltimore and is begin adopted at other school districts across the country. Meatless Mondays were introduced to the Oakland Unified School District at the beginning of the calendar year, according to the district website. The website cites health benefits of going meatless, such as a reduced risk of chronic diseases including heart disease, lower cholesterol and less overeating.
A report on Planet Green also listed five universities that were adopting the meatless program, including Oxford University, the University of Maryland and the University of California. School cafeterias removed meat from one of their cafeterias and beef from all of them to support the meatless movement.
Johns Hopkins Hospital is also introducing a Meatless Monday program into the cafe in their Wellness Corner to encourage staff, patients and visitors to adopt healthier eating habits. Executive Chef Shawn Fields said in a press release on the hospital website, "I'm looking forward to helping customers learn that they are not sacrificing taste by eating vegetarian meals." Fields' vegetarian chili is already a popular selection in the cafe and is offered as a regular menu selection. A promotional poster for the Meatless Mondays campaign offers a quote by Fields, "If you think chili needs meat, you don't know beans.
Meatless Mondays are a direct response to a report issued by former U.S. Surgeon General David Satcher, titled, "Healthy People 2010." The report recommended that individuals reduce their consumption of saturated fat by 15%. The 2005 Dietary Guidelines Advisory Committee, which was appointed by the Departments of Health and Agriculture, stated that people who eat more fruits and vegetables enjoy a lower risk of chronic diseases like cardiovascular disease, type 2 diabetes and some types of cancer.
Meatless Mondays are also designed to raise awareness of the health impact of eating too much meat and animal products, as well as the environmental impact of industrial meat production. For schools, meatless fare is a viable option in reducing the cost of school lunches, as well as introducing students to a variety of healthy foods they may not try otherwise. Despite the opposition to the program, it appears that Meatless Mondays are gaining speed across the country, as more schools, hospitals and universities experiment with the program.
February 06, 2017
There are many factors which come into play in determining the quality of your child's education, but one thing that many parents overlook is student-teacher ratio.
February 06, 2017
Does your child struggle to keep up in school? Is he performing well in one subject but not in another? If you answered "Yes" to either of these questions, you may want to consider hiring a private tutor.
February 03, 2017
Learn about how public schools are making their campuses greener through technology investments, policy changes, and eco-friendly student education.


Skip to comments.IPCC: Half of Renewable Energy is Wood, Charcoal, and Animal Dung
Posted on 05/11/2011 9:08:40 AM PDT by wewillnotcomply
The IPCC recently released the Summary of a report about renewable energy. Both Pielke Jr. and Donna Laframboise have mentioned it, and once the final report comes out at the end of the month I'm sure we'll hear more about it. However, in looking over the report I was stunned to find out what the IPCC considers as renewable energy (RE).
This story at Scientific American covers it very well. I recommend reading it.
Here's the problem. The IPCC has different categories of renewable energy. They include solar, wind, hydro, geothermal, ocean, and biomass. Biomass is by far the largest category, it constitutes 79% of all renewable energy. Biomass is broken down into two groups: modern and traditional. Modern biomass is the smaller group at 38%. That means that the IPCC considers the largest single source of renewable energy in the world to be traditional biomass. This image from the report says it all (click to view):
Why is this a problem? Look at their definition of traditional biomass:
Traditional biomass is defined by the International Energy Agency (IEA) as biomass consumption in the residential sector in developing countries and refers to the often-unsustainable use of wood, charcoal, agricultural residues, and animal dung for cooking and heating. All other biomass use is defined as modern [Annex I].
Traditional biomass means cooking on wood stoves, it means difficult wood collection (done mostly by women), it means smoke inhalation and deforestation. Basically, traditional biomass is another way of saying abject poverty. It means no access to energy at all. Calling traditional biomass renewable energy is more than a strech.
It is bad enough that they are considering a lack of access to energy to actually be renewable energy, but what is even worse is that they consider it half of world's total amount of renewable energy!
I mentioned this to a colleague, and he told me it was even worse yet. Burning wood and charcoal creates black carbon. This aerosol is considered to have a warming impact on the atmosphere. Isn't one of the primary goals of renewable energy to combat climate change? After all, the report itself says (pg. 3):
As well as having a large potential to mitigate climate change, RE can provide wider benefits. RE may, if implemented properly, contribute to social and economic development, energy access, asecure energy supply, and reducing negative impacts on the environment and health [9.2, 9.3].
They claim that renewable energy can mitigate climate change and reduce negative impacts on the environment and health. However, their largest since source of renewable energy, traditional biomass, contributes to climate change by releasing black carbon, and has significantly negative impacts on both the environment, through deforestation, and on health, through smoke inhalation.
Including traditional biomass in a report on renewable energy cannot be defended. How can anyone now support renewable energy when it is defined as burning animal dung to heat your home or cook your food? Removing traditional biomass from the list of renewable energies may cut the UN's number in half, but leaving it in place renders the report useless. As the UN defines it currently, supporting renewable energy means supporting abject poverty.
Thanks for posting!
my husband does it all....he gets wood from downed trees locally, or even from our property which has alot of trees...
its hard work....but its using a resource that otherwise would just rot, that needs to be taken care of anyway, and it saves us a few bucks in heating costs....
so whats the problem?
IPCC: Half of Renewable Energy is Wood, Charcoal, and Animal Dung
Oh, for peat’s sake!! More evidence of crap science from IPCC.
Burning sticks and stones and an old bone
Causes global warming and smoggy ozone!
If you search information about rocket stoves and other alternatives to traditional self destructive native practices, you will find slightly conflicting data about the results of the traditional uses of biomass, but the conflicts appear to be mostly incidental. The differences are in exactly how inefficient fires are, precisely how many die from the smoke and burns, etc. The basics of poverty and little hope for improvement seem to agree.
But even with more efficient stoves, reasonably usable water hauling containers, village wells or whatever, if there is no coordination, no rule of law, if there is no person or entity keeping the impoverished masses from acting like locusts and turning the surrounding area into a wasteland, there is still no fuel nearby , no renewing actually occurring.
This also describes problems with trying to upgrade lives with water or electricity or transportation. You have to set a new paradigm to keep the young bucks from hacking into the water pipes when they are thirsty, or keep everyone from taking the saplings for fuel when trying to set up an orchard or renewable hedgerow for fuel. It is a huge leap going from striving for today day after day to having a plan and hope for tomorrow and next year and the grandchildren.
BUT... Does this actually have anything to do with global warming? Nah.
That doesn’t even take into account the ubiquity of “pull my finger”.
Use of biomass in the developed world is considered modern biomass, not traditional biomass. It is a different category.
“so whats the problem?”
Burning your own locally acquired wood, be it from your own property or not makes you a little more independent from the powers that be. If they can keep you in a situation where the Government can put you in the dark with no heat on a cold winter’s on a whim then you can be controlled.
And when they need to reinforce that knowledge on you they will.
And just like your husband, I will be gathering up the downed trees here for use in my own fireplace. It really makes a difference in the heating bills in the Winter.
My suggestion to the warmists is this: Try growing grass on the roof. Sucks in plenty of CO2, and the clippings make great fertilizer.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.


Karyotypes and Case Studies of Ten Individuals With Suspected Sex Chromosome Anomalies
The problem. This study will involve making a karyotype analysis and a case study of the residents of Woodward State Hospital and School who had been previously reported as having an abnormal X-chromatin constitution. Procedure. Buccal smears were taken from each individual and stained with carbolfuchsin. Cells were observed for their X-chromatin content. Blood samples of each resident were drawn, cultured and harvested according to standard procedures. Chromosomes were counted in 30-50 cells and karyotypes prepared with emphasis on identifying the X-chromosome complement of each cell line. Case studies of the family history and physical features of each individual were done. Findings. Six female residents suspected of having a 45,XO chromosome complement or possible 45,XO/46,XX mosaic condition were found to have a normal 46,XX chromosome complement. Two male residents suspected of having Turner's syndrome in the male were found to have a 46,XY chromosome complement. One male resident with a Klinefelter's phenotype had a 46,XY chromosome complement. One male had a 49,XXXXY chromosome complement. Conclusions. The six females in the study were found not to have Turner's syndrome or mosaicism for the syndrome. Two males suspected of being male Turner's phenotypes were found to have Down's syndrome but no indication of Turner's syndrome. One male was found to have chromatin negative Klinefelter's syndrome. One male had a 49,XXXXY chromosome complement and showed all the phenotypic features of that condition.
- Theses


The 61st session of the Commission on the Status of Women (CSW 61) was held in New York, U.S., from March 13-24, with the theme 'Women's Economic Empowerment in the Changing World of Work'.
The commission is one of the largest annual gatherings of global leaders, NGOs, private sector actors, United Nations partners and activists from around the world focusing on the status of rights and empowerment of all women and girls everywhere.
The elimination of discrimination against women in employment is an important measure to promote women's economic empowerment. In this article, experts of the Women's Studies Institute of China explained discrimination against women.
What Is Discrimination Against Women?
The Convention on the Elimination of All Forms of Discrimination against Women (CEDAW) was adopted at the 34th session of the United Nations General Assembly in 1979. In the convention, the term 'discrimination against women' shall mean, "any distinction, exclusion or restriction made on the basis of sex which has the effect or purpose of impairing or nullifying the recognition, enjoyment or exercise of women, irrespective of their marital status, on a basis of equality of men and women, of human rights and fundamental freedoms in the political, economic, social, cultural, civil or any other field".
What Is Gender Discrimination in Employment?
The Convention Concerning Discrimination in Respect of Employment and Occupation was published by the International Labor Organization (ILO) in 1958.
For the purpose of this convention the term 'employment discrimination' includes:
- Any distinction, exclusion or preference made on the basis of race, color, sex, religion, political opinion, national extraction or social origin, which has the effect of nullifying or impairing equality of opportunity or treatment in employment or occupation.
- Such other distinction, exclusion or preference which has the effect of nullifying or impairing equality of opportunity or treatment in employment or occupation as may be determined by the Member concerned after consultation with representative employers' and workers' organizations, where such exist, and with other appropriate bodies.
Therefore, gender discrimination in employment can be defined as "any distinction, exclusion or preference made on the basis of gender, which has the effect of nullifying or impairing equality of opportunity or treatment in employment or occupation.
Generally speaking, gender discrimination in employment can be divided into direct discrimination and indirect discrimination.
What Is Direct Discrimination?
Direct discrimination, which is also known as overt discrimination, means any direct or overt act that aims to give unequal treatment to an individual or group based on their age, gender, sexuality, skin color, ethnicity or nationality.
For instance, some employers normally set up extra "thresholds" for female candidates in recruitment, leading to women being in a disadvantaged position. These barriers include:
- Stipulating 'only male' or 'male preferred' in recruitment notices or ads.
- Rejecting women's applications if male candidates with the same qualifications submit their resumes.
- Setting up higher educational background requirements for female candidates.
- Setting up additional conditions, such as appearance and height standards for female candidates.
- Stipulating obligations of no marriage or reproduction between certain ages.
What Is Indirect Discrimination?
As opposed to direct discrimination, indirect discrimination, which is also known as covert discrimination, involves subtle or passive acts of prejudice. More often than not these acts are much harder to prove as employment discrimination but the substantial adverse effects do exist, therefore, it can also be called 'substantial discrimination'.
Employers' discriminatory behaviors normally include:
- No written examination or reexamination opportunities for female candidates.
- Expressing the complex of 'male preferred' intentionally or unintentionally in job interviews.
- Frequently enquiring about marital status and thoughts on family planning in job interviews.
- Employers stress that the job vacancy requires frequent overtime, business trips or a hard working environment and it is therefore more suitable for men.
- Enquiring about female candidates' fertility willingness or 'second-child' plans.
(Source: Women's Studies Institute of China / Translated and edited by Gender Study Network)