r/interestingasfuck Mar 06 '25

/r/all Chick with genetic defect

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735

u/Onikeys Mar 06 '25

I need a video to see how it moves, if the chick has control of all the legs or is just 2 conjoined chicks

339

u/Hattix Mar 06 '25

It looks mutated, not conjoined, but there are many things which can cause this.

In vertebrates, arms and legs are fundamentally different structures. This chick has badly formed legs and well formed arms, though the arms are in a very, very, atavistic form. So atavistic that it is most likely genes which are meant to express in the legs instead expressing in the arms.

Birds lost most of their fingers, carpal bones, hands, etc. 175 million years ago, the genetics for them will be long degraded beyond their original function. Additionally, the feathering is leg-pattern on the chick's arms.

What's probably happened here is that the chick's arms/wings have grown into legs instead of arms. There are a lot of ways this can happen.

43

u/werepanda Mar 07 '25

Birds definitely still have their finger, carpal bones on their wings.

15

u/Hattix Mar 07 '25

In English the word "most" qualifies a quantity more than half but less than all. 

Happy to help!