This is also what makes people unable to dive into the sea by themselves to explore the seabed, but need special ships with special reinforcement compartments to do that. Current military submarines only reach an average maximum depth of about 300-400 m. Yet there are marine creatures that can swim around at depths of up to several kilometers without any special measures. So, how did they do it?
First of all, let’s go over a few of them. Pelican eel
Pelican eel. With their oversized jaws and stretchable sub-jaws, they could swallow prey even larger than them.