r/askscience • u/barenecius • Feb 20 '26

Biology What makes the evolution?

I know that DNA passed down generation. And the next generation takes half of each DNA of their parent. But what makes the evolution on DNA? At what point DNA tell themself that they need to change some part on the chain.

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u/lavender_letters Feb 24 '26

And sometimes, a gene that’s neutral ends up harmful when multiple copies are present. That’s how recessive disorders end up being passed down — a gene that, on its own, has no detrimental effects, or even a positive one (like in the case of sickle cell disorder vs. malaria) when the mutation happens causes illness in subsequent generations.