In evolution, does a whole species evolve simultaneously or does it effect just one specific creature which then passes on its evolved genes to its offspring? i.e the first monkey to stand upright had an advantage over other monkey hence mated more often
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Lucky_Marty
ANSWERS: 2
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The latter. Individuals with genetic mutations that help them live longer/better pass on their genes. If enough individuals with the same mutation reproduce, the species as a whole can acquire this mutation OVER TIME.
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A bit of both. In some cases, a mutation appears in one animal and spreads from that animal's offspring. But in other cases, there is already variation across the whole group, so the whole group changes together. For example, if a gene for an extra colour sensor in the eye appeared, and was massively advantageous, then it would spread by the first mechanism. But if, for example, the weather got colder and thicker fur was an advantage, there would probably already be some variation in fur thickness across the whole population. In that case, all the thick-furred would be advantaged, and all the thin-furred disadvantaged. People tend to think mostly of the first mechanism - a valuable invention spreading from a single starter. But scientists now believe that the latter occurs much more often: a population with quite a lot of variation in its genome encounters changed circumstances, and the genome is "pushed" in the direction which gives the most advantage.
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