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Can sexual selection operate in temperature dependent sex determining organisms? Yes! Crocodiles are indeed a good example as the sex in determined by the temperature (ref) and they have some traits evolving through sexual selection (ref). I think you went almost all the way to the answer in your thoughts. Let's categorize things a little bit and talk ...


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The implied subject of your question is the prezygotic barrier and is one of the possible determining mechanisms of speciation, the others being temporo-spatial (meaning different time or place), behavioral, and mechanical (the organisms don't fit together, physically). Fundamentally, this means that gamete cells of each organism are chemically ...


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From jzx's answer, I thought of a possible answer to my own question. Maybe not producing identical twins all the time is a paradoxical evolutionary stable strategy for the following reason: Until recently in evolutionary history, the population remained constant when parents only had enough food to feed 2 children. Siblings didn't evolve to be fully ...


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What you describe could have happened under the right conditions. However, there are a few things you haven't considered. Because humans are especially altricial, always having twins would double the cost of children on parents. The benefit of sexual reproduction is immune diversity. So a population like this could be far more vulnerable to disease. So ...


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If we produced identical twins all the time then we'd completely lose genetic diversity which would, I assume, overwhelmingly compromise our adaptive capabilities. Don't forget, those identical twins then need to reproduce with other identical twins of others families. Moreover, and this is the more obvious explanation, as a consequence deleterious recessive ...


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Super oober short answer: The father is Cc, the mother is cc, there is a 50% chance the children will be albino (as you predicted). An explination on Mendelian genetics: First let's look at (what a lot of people consider) the normal Mendel table from here: Since the dad is normal, that means he has at least one Normal Gene. Which makes him C ? . We ...


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Change in genetic variance From what I have been taught, Natural Selection (or even Artificial Selection) is great for panning favorable genes from a species and bringing them to the fore, however, it does not introduce new genetic changes. Yes, you are pretty much right. In a given population, directional selection will ultimately reduce genetic ...


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You're right that the mutation must be in a germ cell in order to be passed on. Most errors are introduced during DNA replication (at a rate of around 10-10), which occurs a number of times between the zygote stage and mature gametes. This book estimates that there are 24 divisions between zygote and egg and 23n+34 divisions between zygote and sperm, where n ...



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