Your Inner Fish: A Journey into the 3.5-Billion-Year History of the Human Body

by Neil Shubin

you see an entire menagerie.

a continuum of forms showing beyond doubt that over time the bones at the back of the reptilian jaw got smaller and smaller, until they ultimately lay in the middle ear of mammals.

but by repurposing existing ones.

Bones originally used by reptiles to chew evolved in mammals to assist in hearing.

The key nerve for the functioning of both bones is the second-arch nerve, the facial nerve.

Our middle ear contains a record of two of the great transformations in the history of life.

but some of the most fascinating properties of these muscles relate to their involuntary action.

Organs can come about for one function, only to be repurposed over time for any number of new uses.

but they were debating one of the most important concepts in all of biology.

This biological “law of everything” is that every living thing on the planet had parents.

every living thing sprang from some parental genetic information.

Or does it continue to 3.8-billion-year-old pond scum, and beyond?

This prediction is true: the earliest mammal is much more recent than the earliest reptile.

related to me to different degrees.

You would have the same chance of seeing your ball go up the fifty-first time you dropped it as you would of finding strong evidence against these relationships.

It includes every animal from insects to humans.

They are clear evidence of the pitfalls of having an inner fish. Fish do not walk on two legs.

due to our having a body built for an active animal but the lifestyle of a spud.