Some Assembly Required: Decoding Four Billion Years of Life, from Ancient Fossils to DNA

Expanding on his previous two best sellers (Your Inner Fish; The Universe Within), Shubin (organismal biology & anatomy, Univ. of Chicago) shows how evidence from fossils combines with discoveries from DNA to promote new understandings of evolution. Taking a tour of the ideas of scientists over centuries, Shubin explains how creatures often did not develop new organs over time, as science once asserted, but rather repurposed existing organs to serve new functions. The author notes that changes in the timing of embryonic development, controlled by DNA, lead to differences in bodies. These changes, he says, act as recipes for bodies, encoded in DNA, passed along generations. Minor alterations in the code can have outsized ramifications, sometimes resulting in genetic defects or disease. Remnants of the molecules formed from these recipes can be traced through the ages, as clear a history as that found in fossils. Shubin explores deviations in genetic code, copycat codes, invasions of viruses and bacteria (co-opted for our use) into human DNA, and current experiments in genome editing.