This is the only species we know capable of regulating its own oxygen intake and transporting it to different parts of the body. Science can’t explain how this is possible.
The lack of a spinal column means that the hagfish is extremely flexible. It can even tie itself up in knots in order to scrape the slime off its body and escape danger.
Hagfish do not fear enemies much larger than themselves. Sharks and any other killers that might foolhardily go in for the kill are often choked in seconds by their slime.
5. Inside and out
To consume its prey (which is often dead or dying) not only does it scrape the flesh away with its teeth, but it can also crawl inside the creature and eat its way out from inside.