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The only vertebrate that eats with its mouth shut

作者:车恰沸    发布时间:2019-03-07 02:19:00    

By Colin Barras THE Pacific hagfish is the only vertebrate that can obey the cardinal rule of the dinner table: don’t eat with your mouth open. Uniquely among the 50,000 vertebrate species alive today, it can absorb nutrients through its skin. Vertebrate skin is impermeable to minimise chemical exchanges between the body and its surroundings. This is why backboned animals can live in salty or fresh water – and how they avoid excess water loss on land. But the primitive hagfish, thought to be as close as we can get in a living animal to the first vertebrate,

 

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