are nematodes sexually dimorphic
By Laura Klappenbach. Sexual dimorphism is the difference in morphology between male and female members of the same species. Sexual dimorphism includes differences in size, coloration, or body structure between the sexes.For example, the male northern cardinal has a bright red plumage while the female has a duller plumage.Male lions have a mane, female lions do not. Below are some additional examples of sexual dimorphism: 1  Male elk (Cervus canadensis) grow antlers, while female elk do not have antlers.exual dimorphism includes differences in size, coloration, or body structure between the sexes. For example, the male northern cardinal has a bright red plumage while the female has a duller plumage. In most cases when size differences exist between the male and female of a species, it is the male that is the larger of the two sexes. But in a few species, such as birds of prey and owls, it is the female is the larger of the sexes and such a size difference is referred to as reverse sexual dimorphism.exual dimorphism includes differences in size, coloration, or body structure between the sexes. For example, the male northern cardinal has a bright red plumage while the female has a duller plumage. Sexual dimorphism is a phenotypic differentiation between males and females of the same species.exual dimorphism is maintained by the counteracting pressures of natural selection and sexual selection. For example, sexual dimorphism in coloration increases the vulnerability of bird species to predation by European sparrowhawks in Denmark. Most nematodes are dioecious, but some are monoecious and a few parthenogenetic forms are known. Dioecious species exhibit sexual dimorphism with females being larger than males. Males have a curled tail and more external ornamentation such as bursae, alae, and papillae (the males have more jewelry).ematodes exhibit determinate cleavage and nematode development has been well studied. The fate of each blastomere is determined early during cleavage and this has allowed researchers to mark and map the fate of each cell to learn which tissues will develop from a given cell. This is illustrated in Figure 22.33. Associated with morphological sexual dimorphism are several behavioral differences between males and females. Many of these are related to locating a mate, competition between males, and female choosiness.Animals also show sexual dimorphism relating to their roles as parents.Many parents continue to provide for their young after birth, with the female performing the bulk of the care in most species.ermanent sexual dimorphism can be nearly or completely independent of seasonal conditions and is characteristic of many worms, arthropods, and vertebrates. The males are much smaller than the females, for example, in nematodes, daph-nids, and ixodid ticks. Sexual dimorphism in birds can be manifested in size or plumage differences between the sexes. Sexual size dimorphism varies among taxa with males typically being larger, though this is not always the case i.e. birds of prey and some species of flightless birds.exual dimorphism is maintained by the counteracting pressures of natural selection and sexual selection. For example, sexual dimorphism in coloration increases the vulnerability of bird species to predation by European sparrowhawks in Denmark. Permanent and seasonal sexual dimorphism are distinguished. Permanent sexual dimorphism can be nearly or completely independent of seasonal conditions and is characteristic of many worms, arthropods, and vertebrates. The males are much smaller than the females, for example, in nematodes, daph-nids, and ixodid ticks.ermanent sexual dimorphism can be nearly or completely independent of seasonal conditions and is characteristic of many worms, arthropods, and vertebrates. The males are much smaller than the females, for example, in nematodes, daph-nids, and ixodid ticks. Common and easily identified types of dimorphism are ornamentation and coloration. A difference in coloration of sexes within a given species is called sexual dichromatism, which is commonly seen in many species of birds and reptiles.exual dimorphism is maintained by the counteracting pressures of natural selection and sexual selection. For example, sexual dimorphism in coloration increases the vulnerability of bird species to predation by European sparrowhawks in Denmark. The somatic muscles, pseudocoel, and cuticle function together as a hydrostatic skeleton in nematodes. The platymyarian type of muscle cell has contractile fibers on one side, next to the hypodermis, and a noncontractile myocyton bulging into the pseudocoel (Figure 22.8).ematodes exhibit determinate cleavage and nematode development has been well studied. The fate of each blastomere is determined early during cleavage and this has allowed researchers to mark and map the fate of each cell to learn which tissues will develop from a given cell. This is illustrated in Figure 22.33. Other possible examples are for secondary sex characteristics, body size, physical strength and morphology, ornamentation, behavior and other bodily traits. Traits such as ornamentation and breeding behavior found in only one sex imply that sexual selection over an extended period of time leads to sexual dimorphism.exual dimorphism is maintained by the counteracting pressures of natural selection and sexual selection. For example, sexual dimorphism in coloration increases the vulnerability of bird species to predation by European sparrowhawks in Denmark.
Yes