Your inner reptile

Your Inner Reptile All around us, evidence of evolution is undeniable. From the anatomy to genetic makeup of our genes, our existence can be traced to animals millions of years ago. Neil Shumin demonstrates how we are victims of our inner reptiles, each day we live.
The earliest evidence is demonstrated in the remnant egg yolk at the beginning of embryonic development of a human. The egg yolk is still a dominant feature in the egg of a reptile and birds. The baby is also surrounded by amnion, a fluid cushioning the embryo. When reptiles ventured into the land, they faced a very imminent threat of having their eggs dry (YouTube). Amphibians turn to water for laying eggs, but reptiles came up with a more radical solution. Due to the harsh environmental conditions, they enclosed their embryo in a sac full of fluid (amnion) and covered it with a protective shell. This shell prevented the eggs from drying, and they could now lay eggs on the land and invade the land.
Such changes and evolution are not only evident in the comparison of our anatomy and that of reptiles, but also on the genetics. It is possible to compare genome of a human to genome of a fish or a chicken. Studies were conducted to look for a gene responsible for yolk production in the egg. Reptiles and birds have several of these genes. On researching humans for these genes, they were too observed to have yolk genes (YouTube). The genes were however dormant, not functional because our ancestors had stopped relying on the yolk for nourishment of the embryo. The genomes, however lie deep the genes like fossils from the past. These findings show that humans are distant relatives of an egg laying animal, they are related to the reptiles.
The skin of a reptile is dry and rough, covered with a thick layer of dead tissue to insulate against water. This layer has been demonstrated in humans. However, glands on the skin of humans produce a lubricant, making the skin of a human soft to the touch and moisturized.
In South Africa, a species named Mammal-like reptiles were discovered fossilized (YouTube). They were reptiles with mammal-like features. Reptiles have sharp teeth, but these mammal-like animals had started to have differentiation of teeth. Their teeth were designed for better carnivore diet, but the differentiation came with it matching of teeth as strategy, to get a bite, and strengthened them with more teeth roots.
Mass extinction eliminated most, but some survived with new better opportunity. During this time, some species were completely wiped off, but the ones that survived had better chances of survival. Among them were the mammal-like reptiles. They had resorted for underground homes to survive the extreme heat (YouTube). In these surroundings, whiskers may have developed then as sensory organs to lead them in the underground tunnels. Years later, they started using the body hair for another purpose; for warmth. Hair from ancestors after the aftermath of the great extinction then became part of the mammalian body.
Lab study of a developing lab tooth shows skin fold and form the tooth. This is not a new phenomenon of skin folding to form some vital connective tissues such as hair and glands. The E. D. A gene control the formation of these organs from the skin. Abnormality of this gene leads to conditions such as the inability to dissipate internal high temperatures.
The ear was another great development in the early mammals. This explains the high auditory perception in humans as they formed the three ear ossicles for better sound perception. The jaw bone had with time reduced in size with redundant bones, which would then become the ear bones. They redundant jaw bones took up another job in the ear becoming the ear ossicles. Hydrocardium, one of the earliest mammal, had started the journey of well-developed ear ossicles (YouTube). Too much sensory processing also had led to a bigger brain.
Years later, the dinosaurs pushed these small animals into hiding and until years later, when the dinosaurs became extinct did the mammals came up from underground and continued with the evolution. In effect, every day of our living reflects the inner reptile, starting from our anatomy, embryonic development among others.
Works Cited
YouTube,. 02 Your Inner Reptile – (Full Episodes). N. p., 2014. Web. 12 Dec. 2014.