Book Review: Your Inner Fish
Neil Shubin's Book About Evolution, Descent and Hemorrhoids
Nov 12, 2008
Neil Shubin is a paleontologist who has spent most of his career working with fish. A series of events led him to a position teaching anatomy at the University of Chicago, a position not obviously suited to a professional paleontologist. It turns out that a background in paleontology is of great advantage when teaching human anatomy.
The Road Map to the Human Body
According to Shubin, "The simplest way to teach students the nerves in the human head is to show them the state of affairs in sharks. The easiest road map to their limbs lies in fish. Reptiles are a real help with the structure of the brain." Human beings carry their evolutionary roots throughout their bodies and a grasp of simpler creatures allows medical students to get a handle on some of the more convoluted structures in the human form.
A Fish Out of Water
The first section of Your Inner Fish deals with Shubin's search for a fossil of a creature that The Theory of Evolution by Natural Selection said must exist but had yet to be found.
An intermediate stage between fish and reptile had long been hypothesized to have existed during the Late Devonian, some 375 million years ago. Sure enough, in some exposed rocks from the Late Devonian, Shubin's team discovered something positively astounding. A fish with wrists.
Named "Tiktaalik" with the help of Inuit elders in the region of the Canadian Arctic where the fossil was found, the creature exhibits numerous transitional features as water breathing fish began the long, slow evolutionary climb onto land.
It's all in the Wrist
Tiktaalik, like all fossils, has an interesting story to tell. In this case, it's the story of how human beings are put together. Shubin explains how the development of Tiktaalik's wrists as analogous to the single upper arm bone, two bone forearm, many boned wrist structure found in every mammal's anatomy. Further, he shows how the fin structures of fish like Tiktaalik hold the blue print for the mammalian paw and the opposable thumb structures in the hands of primates.
Evolutionary Missteps
Through examples in fish, insects, reptiles and other primates, Shubin details the many and quirky twists and turns that happened over billions of years of evolution that have resulted in human beings. The causes of such human afflictions as obesity and heart disease and even hemorrhoids are traced to our abandoning the hunter gatherer lifestyle that humans evolved for in favour of a modern existence dominated by office work and take out food. Choking and sleep apnea are part of an evolutionary trade off made to favour the ability to speak. Hiccups, hernias and our susceptibility to microbial infection all have their explanation in our inner fish.
Neil Shubin provides an evolutionary road map to the human condition, free of the weight of scientific jargon and mile long Latin words. He has taken the adventure of a lifetime, made an invaluable contribution to the study of The Theory of Evolution by Natural Selection and he has had the good grace to write an accessible, entertaining book to allow everyone to share the joy and excitement of the experience.
Your Inner Fish is published by Pantheon Books, a division of Random House Inc., New York. Copyright 2008. ISBN: 978-0-375-42447-2
