Shubin Chapter Summary

Shubin starts off by telling us about his discovery of Tiktaalik, a fish which represents the evolutionary transition between fish and primitive land-living animals. Shubin states that, “Tiktaalik has a shoulder, elbow, and wrist composed of the same bones as an upper arm, forearm, and wrist in a human,” showing its connections to the human body. He then moves onto the history of our hands, referring to Sir Richard Owen’s discovery that there was a fundamental design in all vertebrate land animals along with many marine animals. Limbs had a one bone, two bones, and several little bones structure which penguins, bats, seals, whales and even dinosaurs had. Shubin then goes into detail, connecting this all to genetics, discussing a gene which …show more content…
Teeth are a great way to discover when an organism existed and based on the shape, figure out what they ate. Shubin describes that many of the hard structures of organisms, such as bones and armor, originated from teeth. Without the development of teeth, organisms would not have feathers, hair, or even mammary glands. Shubin moves onto the head describing that every vertebrate animal starts with four arches (Branchial arches/gill arches) which develop into different functions, concluding that we are all modified sharks. Shubin moves onto the nose and the sense of smell. 3% of our genome is devoted to the sense of smell which is why we are able to smell and identify around 10,000 unique smells. Not only are there two different proteins which determine whether an organism can smell in water or in the air but like other gene traits, scent genes can be tracked by mutations because there is a limited amount of change that can occur and creatures who are more related to each other have lost similar scents as a result of