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Temperature-dependent sex determination (TSD) is a type of environmental sex determination in which the temperatures experienced during embryonic/larval development determine the sex of the offspring. [1] It is observed in reptiles and teleost fish, with some reports of it occurring in species of shrimp.
In species that use the XY sex-determination system, parthenogenetic offspring have two X chromosomes and are female. In species that use the ZW sex-determination system the offspring genotype may be one of ZW (female), [30] [31] ZZ (male), or WW (non-viable in most species, [33] but a fertile, [dubious – discuss] viable female in a few, e.g ...
Selective breeding (also called artificial selection) is the process by which humans use animal breeding and plant breeding to selectively develop particular phenotypic traits (characteristics) by choosing which typically animal or plant males and females will sexually reproduce and have offspring together.
In all cattle species, a female twin of a bull usually becomes infertile due to intrauterine exposure to high testosterone levels. She is functionally a partial intersex, and is commonly called a freemartin. A wild, young, unmarked bull is known as a micky in Australia. [7] An unbranded bovine of either sex is called a maverick in the US and ...
Some of the earliest examples of parent-offspring conflict were seen in bird broods and especially in raptor species. While parent birds often lay two eggs and attempt to raise two or more young, the strongest fledgling takes a greater share of the food brought by parents and will often kill the weaker sibling ().
Females that mate with more than one male obtain the aid of both and as a result of all three parents providing food and care to the offspring there is an increase in the survival of their young. The amount of help is determined based on mating share and paternity share. (Mating Systems, p 275)
In biology, offspring are the young creation of living organisms, produced either by sexual or asexual reproduction. Collective offspring may be known as a brood or progeny . This can refer to a set of simultaneous offspring, such as the chicks hatched from one clutch of eggs , or to all offspring produced over time, as with the honeybee .
Sexual selection is an evolutionary concept that has been used to explain why, in some species, male and female individuals behave differently in selecting mates. In 1930, Ronald Fisher wrote The Genetical Theory of Natural Selection, [3] in which he introduced the modern concept of parental investment, introduced the sexy son hypothesis, and introduced Fisher's principle.