Chapter 3: Handy Genes

For me, this chapter was the most interesting so far. I already guessed that i would enjoy reading this chapter because genes are so complex and fun to learn about. Some of the information i already knew, others i just learned, and there are still some that confuse me, but i still found it interesting.

The most interesting part of the chapter was that chickens and skates have similar genes to us. I never thought that creatures that are so far less advanced than us would have anything in common like that. I also liked how he mentioned that errors in the Sonic Hedgehog can cause multiple defects in the hand. He also noted that excess ZPA could cause birds to have pinkies or thumbs, which also explains why some humans have extra fingers or toes. I found it interesting to see how the injection of vitamin A manipulated the embryo in such a significant way.

I just wish that this chapter mentioned the Tiktaalik more, because that's what i was expecting the chapter would mention.

-Shay Fajardo