[Virginia-American]

You're welcome!

Another interesting vestigism is the recurrent laryngeal nerve. It's the part of the vagus nerve that controls the vocal cords in mammals. The interesting thing is that it starts in the brainstem, goes into the chest, loops around the aortic arch, and then goes back up into the throat.

This adds about 15 feet in a giraffe.

It's too late for me to hunt down a good reference, but basically what happened is that in fish the nerve goes to a gill, and the heart is much further forward.

The mammalian heart moves down into the chest, and the topology forces the nerve to follow it.

[Seamoth]

Fascinating. So you're saying that there's no "reason" for the nerve to wrap around the heart before ending at the throat? Now that you mention it, the pulsation of fish gills do resemble the vibration of vocal cords!