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HEMIZYGOSITY. "Meiotic recombination establishes connections between homologous chromosomes to promote segregation. Hemizygous regions of sex chromosomes have no homologous chromosome to recombine with yet must be transmitted through meiosis. An extreme case of hemizygosity exists in the genus Caenorhabditis, where males have a single X chromosome that completely lacks a homologous partner." https://lnkd.in/evK6USz View in LinkedIn

ISOGAMY. "There are numerous species which are sexual and do not have this problem because they do not produce males or females. Yeast, for example, are isogamous sexual organisms which have two mating types which fuse and recombine their haploid genomes. Both sexes reproduce during the haploid and diploid stages of their life cycle and have a 100% chance of passing their genes into their offspring." https://en.m.wikipedia.org/wiki/Evolution_of_sexual_reproduction#Two-fold_cost_of_sex View in LinkedIn

“FAST REPRODUCTIVE STRATEGIES (R STRATEGIES) are used by mice and rabbits to make many offspring quickly. Typically, these organisms are small, live short lives and rapidly come to sexual maturity. Their numerous offspring are swiftly independent, with low survivorship.” https://lnkd.in/e3_feD9 View in LinkedIn

ANISOGAMY. "It is widely believed that a disadvantage of sexual reproduction is that a sexually reproducing organism will only be able to pass on 50% of its genes to each offspring. This is a consequence of the fact that gametes from sexually reproducing species are haploid. This, however, conflates sex and reproduction which are two separate events. The "two-fold cost of sex" may more accurately be described as the cost of anisogamy. Not all sexual organisms are anisogamous." https://en.m.wikipedia.org/wiki/Evolution_of_sexual_reproduction#Two-fold_cost_of_sex View in LinkedIn

SEXUAL POLYGAMY. “Polygyny is one male with many females (lions) versus polyandry or one female with many males (bees). Many primates and dolphins are promiscuous, with multiple indiscriminate matings.” https://lnkd.in/e3_feD9 View in LinkedIn

ASEXUAL ADVANTAGE. "In most multicellular sexual species, the population consists of two sexes, only one of which is capable of bearing young (with the exception of simultaneous hermaphrodites). In an asexual species, each member of the population is capable of bearing young. This implies that an asexual population has an intrinsic capacity to grow more rapidly with each generation." (John Maynard Smith). https://lnkd.in/eQbyfmX View in LinkedIn

SEXUAL MONOGAMY. Over 90% of birds mate with a single mate for more than one breeding season, including eagles, albatross, swans, and swallows. These require more extended rearing of the offspring. https://lnkd.in/e3_feD9 View in LinkedIn

TWO FOLD COST. "The evolution of sexual reproduction is a major puzzle for biologists. The two-fold cost of sex is that only 50% of organisms reproduce and organisms only pass on 50% of their genes." https://lnkd.in/e3hvRP7 View in LinkedIn

ALLOGAMY VS AUTOGAMY. “Allogamy" (cross-fertilization) is a term used in the field of biological reproduction describing the fertilization of an ovum from one individual with the spermatozoa of another. By contrast, autogamy is the term used for self-fertilization.” https://en.m.wikipedia.org/wiki/Allogamy View in LinkedIn

“EXTERNAL SEXUAL SEXUAL REPRODUCTION is where the egg is fertilized outside the female, such as in corals, fish, plants, fungi. Aquatic creatures often use this method because their sperm will not desiccate. Broadcast spawning in reef fish often release eggs and sperm simultaneously such as in boxfish, abalone and corals. Demersal spawning involves laying eggs and sperm into a protected place (clownfish).” https://lnkd.in/e3_feD9 View in LinkedIn