I found this fascinating and oddly disturbing:
Source: Wikipedia
Hagfish literally tie themselves in knots to escape a tricky situation – and that includes tying their bodies into complicated three-twist knots.
In many ways, hagfish are extraordinary. They are long, eel-like marine animals that carry far more blood relative to their body volume than any other fish, have four hearts – and only half a jaw.
It is partly because of this last feature that it is so useful for hagfish to tie knots in their long bodies. When the animal ties a knot at its tail end and slips it along the body to the head, it forms a broad flat surface that the hagfish’s upper jaw can work against, creating a makeshift lower jaw. Slipping a thick body knot along its body can also help a hagfish pull its head out of a tight spot if it gets stuck during hunting or feeding. [NewScientist (11 January 2020)]
Sounds like a critter designed by a committee meeting at a bar, doesn’t it? I mean, four hearts?!
And I must be in an odd frame of mind, because I keep wondering if our Universe is just a little particle in the gut of a cosmic hagfish …
