When i got this packet, I thought to myself this is huge and its going to suck, but I was reading it and i actually found a lot of things interesting. I found out that vertebrates enter our world approximatley 350 million years ago and this event changedlife on earth forever. Land vertebrates are the descendents of bony fishes and had to adapt to the harsh conditions ashore. If you live on land then that means you have to breath air and the descendants had lungs which allow absorption of oxygen directly from air. I also learned that there are around 7,000 living species of reptiles, including lizards, sankes, turtles, and crocodiles. Their dry skin is covered with scales to prevent water loss and to prevent them from drying out. This ferature also allows the animal to lay eggs on land. Like most fishes, reptiles are cold blooded and they get very sluggish in cold temperatures. This feature tends to keep them out of the cold regions especially on land because the air temperature is colder then the ocean temperature. Last but not least i would like to talk about sea turtles. They belong to an ancient group of reptiles. They have an armored shell that is attached to their backbone, therefore if you take it off they would die. Also unlike land turtles, they can not retract their head into their shell and their legs are bigger then land turtles because it helps them swim. Overall this packet was pretty interesting.