Honors Bio class 10

Today in class we talked about evolution and the importance of fossil evidence to prove this theory. We reviewed the process of uncovering a fossil and how fossils are formed through sediment and pressure so that the bones are hardened. Then we took a closer look at a particular type of transition fossil called the Tiktaalik. The Tiktaalik was a very important piece of evidence for evolution because it displayed the transition between a fish and a land animal. You are able to see the changes in its bone structure along its ribs, skull, "arms" and "legs." One can compare it's arm to the structure of a human arm, in order to observe the differences and similarities. Its ribs are also expanded like a humans, so that it can lie on its stomach and maneuver around obstacles better. This important change was prompted by the movement of the tectonic plates, which led to drastic changes in the environment. the Tiktaalik adapted because it was forced to live in shallower waters, which made land more convenient and readily available. Land also offered a larger diversity of food, such as insects, for the Tiktaalik to eat. After the lecture, we visited the museum to view the exhibit on the Tiktaalik: