The Sixth Extinction Chapter Summary

The Sixth Extinction: An Unnatural History details the continued loss of biodiversity that has occurred since the rise of mankind. Elizabeth Kolbert claims that we are now in the midst of a sixth mass extinction, and that, if precautionary measures are not taken, the loss of biodiversity would be catastrophic. Chapter one begins by describing the golden frogs in the town of El Valle de Antón, and how they were beginning to disappear. The frogs disappeared due to a fungus called Batrachochytrium dendrobatidis. This fungus has spread around the world at a lightning-quick rate, killing all sorts of amphibious organisms at an unnatural rate. The cause of the rapid spreading of the fungus has been theorized to be due to humans inadvertently spreading

However with the rising temperatures in the tropics, the plants and animals are moving to higher and higher altitudes. The most concerning issue is that the climate seems to be rising at an alarmingly fast rate. At this rate, some species will not be able to migrate quick enough to survive the sudden rise in temperature. Many, many species are going to die out thanks to the change in climate. In chapter nine Kolbert writes about the lack of undeveloped land that is left in the world. The little land that has remained undeveloped exist as small ‘islands’ within an ocean of developed land. In one of these land ‘islands,’ Kolbert discusses the decline in species of birds. These islands also have an overall lower biodiversity when compared to the surrounding land, which can be attributed to the severely limited amount of space and organisms that can live in the space. One of these islands, a rainforest, has an amazingly large amount of biodiversity. However due to the small space available, the biodiversity is dropping at a rapid rate. This is bad for the ecosystem as a whole, since if one organism goes extinct, all of the other species are affected in some

Kolbet then goes on the tell that this is due to invasive species: species that are introduced to an area where they are not native. This can lead to two outcomes: either the species will not be well suited for the new environment, and as such will die out very quickly, or the new species will flourish and the organisms that lived there before will be killed as they have no defense mechanisms to defend themselves. Humans are the leading cause of invasive species, as we transport organisms around the world. Kolbert then moves to chapter eleven in which she visits a zoo and finds a sumatran rhino that is one of five that are still living on the planet. These rhinos were once found all over the Himalayas, however when they began to become endangered, people swooped in to try to save the species. The people saved some rhinos, however the rhinos were unable to live under the various conditions that existed in the zoos. Eventually, they decided to artificially inseminate the rhinos, in hopes that the species would continue living. Kolbert then asks a question: why is it that giant animals go extinct so quickly? It is theorized that climate change could have killed many species, but the more likely answer is that humankind killed these giant animals. Prior to the rise of mankind, being a large creature was advantageous,