This is the eBook version of the printed book. This Element is an excerpt from Curious Folks Ask 2: 188 Real Answers on Our Fellow Creatures, Our Planet, and Beyond (9780137057399) by Sherry Seethaler. Available in print and digital formats.   Now revealed: scientific secrets of genetics, species, extinction, evolution, and animal thought!   Zoologists and conservationists are making heroic efforts to rebuild populations of certain animal species on the verge of extinction. These populations are often rebuilt from very small numbers of individuals. What risks do these populations face as a result of this lack of genetic diversity? The rebuilding of the California condor population is a case in point....