Status Updates From Your Inner Fish: A Journey ...

Open and close your mouth:
your teeth always come together in the same position, with
upper and lower teeth fitting together precisely. Because
the upper and lower cusps, basins, and ridges match closely,
we are able to break up food with maximal efficiency. In
fact, a mismatch between upper and lower teeth can shatter
our teeth, and enrich our dentists.

Reptiles also lack the precise occlusion—the
fit between upper and lower teeth—that humans and other
mammals have. Also, whereas we mammals replace our
teeth only once, reptiles typically receive visits from the
tooth fairy for their entire lives, replacing their teeth
continually as they wear and break down.

Our limbs exist in three dimensions: they have a top and a
bottom, a pinky side and a thumb side, a base and a tip. The
bones at the tips, in our fingers, are different from the
bones at the shoulder. Likewise, our hands are different
from one side to the other. Our pinkies are shaped
differently from our thumbs.

This guy is clearly very intelligent but a poor writer