My Inner Fish

     This week, we watched the video series, Your Inner Fish. In it, we learned about some of features that we have that can be traced back to fish and reptiles. These features include hair, our sense of hearing, smell, rough skin, and the ability to push yourself up. We got these features from our common ancestors. From fish, we got features such as dropping gonads, the ability to push ourselves up,  and many other features. From reptiles, we got features such as specialized teeth, hair, and extra ear bones. One thing that I learned about was that at 8 weeks, a fetus has a yolk sac. This is a remnant from  when our ancestors laid eggs. This shows that we have a distant ancestor that laid eggs. The yolk sac is a vestigial structure. We also learned why mass extinctions are important. They allow those who survive to get more opportunities by occupying new niches. After the dinosaurs died out, mammals were able to dominate and come out of their burrows to occupy the niches left by the dinosaurs. If the mass extinction that killed the dinosaurs had not existed, mammals would not have been able to dominate. This video series showed me that although we are distantly related to fishes and reptiles, we still have many features that come from them.

Gorgonopsid teeth that allowed them to shred an chew their food like humans do