Species can settle . This happens when the species’ environment is stable for many generations. Faced with an unchanging niche, the species will start to lose genetic diversity as the blind process of natural selection weeds out genes that aren’t perfectly optimal for that niche. The result will be a relatively homogeneous gene pool and a species

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There’s a theory in evolutionary biology called Fisher’s Fundamental Theorem of Natural Selection. It’s the idea that variance equals strength, because the more diverse a population is, the more chances it has to come up with new traits that can be selected for. No one can know what traits will be useful; that’s not how evolution works. But if you

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Another reason to be cautious is that natural selection is not the only process underlying biological changes over time. If most of the individuals in a population are wiped out in some sort of catastrophe, the lucky survivors are highly unlikely to represent an even-handed sample of all the variation present in the original population. The small

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It's unintuitive at first, but in biology, ecological thinking doesn't concern itself with individual organisms, but rather with entire species . This is because individual organisms aren't adaptive enough to change their behavior in meaningful ways. A tree, a shrub, a weed, a bacterium, even a snail or a bat — these individual organisms have

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