The chapter begins with Terri Roth, a researcher at the Cincinnati Zoo, giving an ultrasound to a female sumatran rhino that she has been trying to artificially inseminate. The rhino, Suci, was the result of Cincinnati Zoo's previous efforts to create offspring between two rhinos, who had three children and one grandchild by 2012. Scientists have gone to great lengths to preserve this species's population.

Sumatran Rhinos are classified as critically endangered because of humans, who have hunted them for their horns and destroyed their habitats for logging and agricultural purposes. Their population has declined by 90% since the 1980's to an estimated 100 rhinos in existence.

In 2014, despite being the first place to successfully breed Sumatran rhinos in 112 years, the Cincinnati Zoo lost Suci. By 2015, only 9 rhinos existed in captivity, including Suci's, brother, Harapan, who was the only Sumatran Rhino in the Western Hemisphere until he was moved to Indonesia.

https://www.youtube.com/watch?v=-IbvHAC3HqE

Kolbert uses the facts that humans were involved in the countless horrific deaths of rhinos and that the survival of the rhino on its own is not likely, to appeal to the sympathy of her readers and spark a desire for taking action to save them from extinction.

The breeding programs meant to save the population of Sumatran Rhinos have been mostly unsuccessful. This is because they are large mammals with long periods of pregnancy, common traits of megafauna that are not very advantageous when humans destroy habitats as quickly as they do. But, she also claims that human efforts and breeding programs are essential to saving a species and making a difference.

In these chapters, Kolbert relies on the logic of her audience to support her claim that humans caused the extinction of the megafauna throughout history. Looking at geological evidence, it is clear that the megafauna disappeared in pulses, occurring at different places and times, and that humans appeared in the same places at roughly the same times. This information also argues against climate change being the cause because it is unlikely that one single climate change could have caused this sequence of extinctions. So, logically, humans must be at fault for their extinctions.

In this chapter, Kolbert introduces the Leipzig Zoo in Eastern Germany and Svante Paabo, a researcher of ancient genetics and DNA. In 2006, Paabo announced the project of sequencing the Neanderthal genome after Neanderthal bones were dug up from numerous sites. After much research and work, he found that the sequences of Neanderthals were very similar to those of humans.

Kolbert establishes the credibility of her and her sources in this chapter. For instance, she cites the work of Svante Paabo, the self-proclaimed "father of paleogenetics" when she talks about the similarities between Neanderthal and human DNA. She also makes herself seem more credible by stating that Darwin, one of the most notable figures in science, agrees with her claim that humans were, in fact the cause of the extinction of the megafauna.

Svante Paabo based his research on the study of genomes. Genomes are the complete set of genetic material in an organism, used to determine how close or distant species are on each other's family tree. The comparison of the genomes of humans and Neanderthals concluded that we share a common ancestor. Kolbert uses the work of Svante Paabo to back up her claim that the difference in human and Neanderthal DNA is what gives us the destructive tendencies that we have. Paabo found that human and Neanderthal gene sequences are very similar, and that some humans shared more DNA with Neanderthals than others. Kolbert reasons that since Neanderthals had a pretty small impact on their environment, and our DNA is quite similar, whatever gives us the ability to destroy our ecosystem exists as a small mutation on the genetic level. In other words, humans have what she calls "the madness gene." The gene that killed off the Megafauna, outbred the Neanderthals, and will, eventually, drive humans themselves toward their own demise.