sexual dimorphism

Examples of sexual dimorphism in the following topics:

• Sexual Selection

  • Sexual selection, the selection pressure on males and females to obtain matings, can result in traits designed to maximize sexual success.
  • The selection pressures on males and females to obtain matings is known as sexual selection.
  • These differences are called sexual dimorphisms and arise from the variation in male reproductive success.
  • Sexual dimorphism varies widely among species; some species are even sex-role reversed.
  • Discuss the effects of sexual dimorphism on the reproductive potential of an organism

• Phylum Rotifera

  • Rotifers are dioecious organisms (having either male or female genitalia) and exhibit sexual dimorphism (males and females have different forms).

• Phylum Echinodermata

  • Echinoderms are sexually dimorphic and release their eggs and sperm cells into water; fertilization is external.
  • In some species, the larvae divide asexually and multiply before they reach sexual maturity.

• Phylum Nemertea

  • Animals in phylum Nemertea show sexual dimorphism, although freshwater species may be hermaphroditic.

• Early Hominins

  • For example, sexual dimorphism was more exaggerated than in modern humans.

• Characteristics and Evolution of Primates

  • The very arboreal gibbons are smaller than the great apes; they have low sexual dimorphism (that is, the genders are not markedly different in size); and they have relatively longer arms used for swinging/brachiating through trees.

• Genus Homo

  • Its degree of sexual dimorphism was less than earlier species, with males being 20 to 30 percent larger than females, which is close to the size difference seen in our species.

• Classification of Phylum Mollusca

  • Sexual dimorphism is seen in this class of animals.

• Advantages and Disadvantages of Sexual Reproduction

  • The fact that most eukaryotes reproduce sexually is evidence of its evolutionary success.
  • Scientists recognize some real disadvantages to sexual reproduction.
  • In sexual populations, the males are not producing the offspring themselves.
  • Why is sexuality (and meiosis) so common?
  • Thus, sexually-reproducing organisms alternate between haploid and diploid stages .

• Plant Reproductive Development and Structure

  • Plants have developed various strategies, both sexual and asexual, to ensure reproductive success.
  • Some plants reproduce sexually while others reproduce asexually, in contrast to animal species, which rely almost exclusively on sexual reproduction.
  • Plant sexual reproduction usually depends on pollinating agents, while asexual reproduction is independent of these agents.
  • All plants have the means and corresponding structures for reproducing sexually.
  • The basic function of a flower is to produce seeds through sexual reproduction.