Chapter 04: The Luck of the Ammonites

In the beginning of this chapter, we view the hill town of Gubbio which is north of Rome described as a municipal fossil. As the city gets inspected, there are visible signs of asteroid interaction in the clay, rocks, and minerals analyzed at the hill town. The passages for the hill town were very tight but “the evidence of the asteriod’s impact” lied in  “thin layer of clay about halfway up the gorge” (p. 71). This realisation would lead to the author looking for traces of asteroid and meteorite interaction in different minerals like limestone, which she would find that iridium in clay was a hint since it was common in meteorites. Eventually leading us to the Cretaceous era, where the author begins to look at how some of the ammonites died resulting in some mass extinctions. However, even though there were hints to how some may have died, it was seen as “unclear what aspect of the impact-the heat, the darkness, the cold, the change in water chemistry-did in the ammonites” (p. 90). This discovery could describe the theme that biochemical systems vary in ability to recover from disturbances since we don’t know if the impact of the volcanoes or asteroids shifted their environment which could result in the effect of their biochemical systems [P/CL].