Legs

Portunidae crab is its family (you can tell by the flattened back simming legs) probably the blue crab also known as Callinectes sapidus. You can easily search this name and find the family history, taxonomy etc

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... have been a bit more flexible, but the general trend seems to have been toward leg loss, as in insects. Plus wings that did not start as legs.

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Because it's not so easy to gain or lose limbs. Even aquatic mammals which seem to have no limbs, have still rudimentary legs. In other words, it is easier to change something than to gain or lose it.

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... or have vestigial limbs that add up to 4 limbs, why is it that there are no, let's say, hexapedal ( it would be possible for a, let's say, 4 legs bird? )

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... the bathroom or take off my pants to change them without washing my hands. I feel like I am spreading "bathroom and poop germs" on to my legs while sitting on the toilet and onto my pants when I pick them up after done using the bathroom. I cant wear shorts or anything that shows my legs ...

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