How did tetrapods evolve their skeletal adaptations?

Response #1 

Student 1, 

Great post on skeletal adaptations of tetrapods –human hands vs chimpanzee hands. At a glance, the hands of human and chimpanzee look nearly identical. They share many characteristics. However, there are many features that set the two hands apart. You have clearly stated some of the similarities and differences between human and chimpanzee hands. Human and chimpanzee hand have the same number of phalanges. In addition, chimpanzee’s fingers are long, and their palm is small when compared to that of humans. However, there numerous other similarities and differences between human and chimpanzee hands. They both have opposable thumbs, but the human thumb is much longer, very muscular, and very mobile when compared to the thumbs of chimpanzees (Young, 2002). When it comes to prints, human and chimpanzee hands, both hand finger and palm prints. However, human fingerprints have a higher ride density when compared to that of chimpanzee (Gargulinski, 2018). Overall, the post is great. 

Response #2 

Student 2, 

Great post on skeletal adaptations of tetrapods –skeletal differences between humans and apes. Although humans and apes diverged from a common ancestor, the human skeleton system has changed significantly after the evolutionary split with apes. You have clearly discussed most of the key skeletal differences between humans and apes. The human skeletal system differs from the skeletal system of apes in many aspects. When it comes to chest or rib cage, humans have a broader chest while apes have rib cages that are round, barrel-shaped (Apes vs Hominin Skeletons, n.d). The pelvis of human is much broader and more "bowl-shaped" when compared to that of apes. The feet of apes tend to be flat-footed while that of humans are arched. When it comes to knee-valgus angle, the valgus angle is larger in humans as when compared to apes (Apes vs Hominin Skeletons, n.d). There are numerous similarities and differences between the skeletal system of humans and the skeletal system of apes, and you have clearly discussed most of them. Overall, the post is great. 

References 

Gargulinki, R. (2018). Human Vs. primate hands. [Online]. Retrieved February 2, 2020, from https://sciencing.com/human-vs-primate-hands-6137415.html 

Apes vs Hominin Skeletons. (n.d). Apes vs hominin skeletons. [Online. Retrieved February 2, 2020, from https://www.pathwayz.org/Tree/Plain/APES+VS.+HOMININ+SKELETONS . 

Young, R. (2002). Evolution of the human hand: The role of throwing and clubbing. Journal of Anatomy, vol. 202 (1): 165-174.