I saw pictures of a praying mantis, that was supposed to look like a leaf. It was scary how accurate it resembled a green leaf. How does the DNA of a bug, know what a leaf looks like?
In: Biology
It doesn’t. It just happens to be that way because of evolution and random genetic mutation, just like how all of us humans look a little different from each other.
Imagine you have 100 praying mantises. 20 of them have polka dots, 20 of them are tie-dye coloured, 20 of them are just bright eye-searing neon hot pink, 20 of them have writing on their bodies that says ‘EAT ME’…and 20 of them look kind of like leaves. Not accurate leaves, but at least they’re green and vaguely leafy.
The 20 that look like leaves are going to be *far* less likely to be found and eaten by predators than the ones that don’t. So those 20 get to survive and pass on their DNA, which makes them look like leaves, to little mantis babies that will also look like leaves.
Say those 20 mantises have 100 mantis babies and they all look like leaves. 20 of them barely look like leaves, 20 look a little more like leaves, and so on until the last 20 look almost perfectly like leaves.
Which ones are more likely to survive and pass on their DNA again? The last group, right?
That’s simplified and sped up, obviously, but that’s ‘survival of the fittest’ in a nutshell. You have some mantises with DNA that happens to make them look like leaves. Over many, many generations, the praying mantises that just so happen to look like leaves are the ones that survive because of the advantage that gives them. The more you look like a leaf, the more likely you are to survive, so you end up with progressively better and better ‘camouflage’. But it’s *not* a conscious, deliberate decision to look like a leaf.
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