<span>b The growth of teeth in chickens supports the hypothesis of a common ancestor between birds and reptiles. This is a generally accepted hypothesis, and i'd go with this answer. Obviously we can't say whether chickens will have teeth with certainty, the chickens with teeth are clearly still chickens, and a baby croc isn't hatching out of a chicken egg any time soon.
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Answer:
The sex chromosomes are referred to as X and Y, and their combination determines a person's sex. Typically, human females have two X chromosomes while males possess an XY pairing. This XY sex-determination system is found in most mammals as well as some reptiles and plants.
Men determine the sex of a baby depending on whether their sperm is carrying an X or Y chromosome. An X chromosome combines with the mother's X chromosome to make a baby girl (XX) and a Y chromosome will combine with the mother's to make a boy.
Explanation:
Answer:
geographical isolation
Explanation:
Reproductive isolation is a process of evolution that ensures that members of different species are incapable of mating and when they do, such mating do not result into any offspring or leads to the production of invalid offspring.
There are two mechanisms of reproductive isolation:
- Pre-zygotic mechanisms prevents fertilization between two different species and these include habitat isolation, mating seasons, mechanical isolation, gamete isolation, geographical isolation and behavioral isolation.
- Post-zygotic isolation prevents the products of fertilization from becoming valid and this include hybrid inviability, hybrid sterility and hybrid breakdown.
<em>Geographical isolation involves the existence of geographical barriers between two populations such that there cannot be mating between the two. The two populations eventually evolve to become different species.</em>
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