A genetic parasite may explain why humans and other apes lack tails
Not having a tail is one way apes differ from monkeys
![Two chimpanzees hang from a rope with two hands above a grassy field. Both are facing away from the camera.](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2024/02/022824_eg_tails_feat.jpg?fit=1030%2C580&ssl=1)
A new study suggests that apes, including chimpanzees and humans, lack tails because a genetic parasite altered a gene important for tail development when the group diverged from other primates around 25 million years ago.
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