Chapter 6 : The Sea Around Us (Angel Jorge)

In Chapter 6 of Elizabeth Kolbert's The Sixth Extinction, readers are introduced to a small island in the middle of the Tyrrhenian Sea called Castello Aragonese. The island was formed many million years ago, due to the pressure between the African and Eurasian tectonic plates in a phenomenon that sometimes causes the release of carbon dioxide. Kolbert travels to the island in the winter in order to investigate the carbon dioxide levels in its surrounding waters. In Chapter 5, Kolbert brings up an important topic, the effect of atmospheric carbon dioxide levels in the Earth's oceans. Right away, the marine life at Castello Aragonese doesn’t look very healthy; the high levels of carbon dioxide in the water seem to be interfering with life. One of the most important ways that human beings alter their environment is by burning fossil fuels. Operating under an old paradigm, scientists believed that burning fossil fuels didn’t alter the Earth’s atmosphere in any major way but under the new paradigm, it seems clear that humanity’s fuel consumption will have major ramifications for the temperature and acidity of the oceans. The most immediate impact of increased oceanic acidity on marine life is the erosion of sea creatures’ shells. Much like the ammonites in the previous mass-extinction, mollusks used to have a huge evolutionary advantage, now they seem to be at an evolutionary disadvantage. There is nothing unprecedented about the projected acidity of the ocean as Kolbert says here,"the oceans have experienced growing and declining acidity at many points in the history of the planet," (Page 117)."Kolbert’s point is that humans are increasing the acidity of the oceans quickly; so quickly, in fact, that species don’t have enough time to adapt to their changing environments. This relates to the theme that humans alter natural systems. Kolbert states that humans' impact on the ocean has left behind a trail of death and we are changing the oceans so severely and quickly that we are wiping out species left and right.