I think all of us here have heard about humans being part reptile and perhaps have even tried to study up on this a bit. It is no secret I have mentioned it many times through the years. Of course with most people who speak of the reptile in the human, the details mostly revolve around the reptilian brain stem and our actions that stem from there. That is no secret either.
Scientifically and medically it has been proven long ago that the oldest part of the human brain is reptile in construct. You can pick up many great books on the brain and find this information in great detail. Since the reptile section of our brain happens to be the oldest section, it is agreed upon by many doctors that it mostly controls our primitive emotional range of fight/aggression or flight/fear; basically our base survival instincts as opposed to the nurturing actions of communal animals or the intellect regions of the brain. And it should be no surprise to anyone that human beings in general have the tendency to be far more aggressive and “cold-blooded” than our mammalian counterparts, probably in-part because of the primal reptilian limbic region of our brains.
However, the brain stem is not the only part of the human body that happens to be reptile in structure. I think most people who mention humans being part reptile do not realize this reality.
The piriformis is a slender muscle that runs from the inside of the sacrum to the top of the femur in humans. Even so it can also be found in reptiles as the caudofemoral elevator muscles. In living reptiles today as well as reptile fossils from creatures long ago the caudofemoral elevator runs from the reptile’s tail to its femur. They are much larger and more developed in the reptile than the human because in a reptile they provide large amounts of force, mainly thrusting, required to extend the leg with power while running. Since the human being is a hybrid of reptile and mammal we do not possess tails and so the caudofemoral elevator evolved (or deteriorated) into the much smaller and less powerful piriformis. Nevertheless it is yet another aspect of the human body that is a remnant of a reptilian structure.
Many knives are constructed with weight saving holes in the blades. Some blades are so thick for their purpose that they become cumbersome to wield or even carry and so holes are pounded into the hot metal during their construction. This obviously cuts down on weight. Our pelvises have something similar. There is a large hole in our pelvis called the obturator foramen. In reptiles today as well as ancient reptile beasts this hole was much smaller. They have and had very little weight bearing need on their pelvis structure. We as upright standing humans require the pelvis to support a great deal of weight. This means that the pelvis from the reptile structure had to change to support such weight. Two major things happened. The first was that the pelvis had to grow larger and much heavier than those of a reptile to support the weight. But where heaviness of bone comes into play, the energy expenditure to maintain it also increases. It seems that the body responded to this demand by enlarging the once small obturator foramen hole of our reptilian counterpart into a decent sized opening to lessen the weight of the bone and allow the pelvis to carry the weight above it more efficiently.
Through studying the human body we can discover a number of interesting features that are reptilian in structure, mixed in with all our mammalian parts, that just goes to show that we are hybrid creatures, split between reptile and mammal. Anyone who studies the natures of both mammals and reptiles can clearly see the major differences in traits, actions, interactions, lifestyles and so many other details. Is it no wonder humans seem to possess a large number of conflicting issues all the way down to DNA structures? The mashing of reptilian and mammalian DNA and everything built upon them both automatically creates strife as they are so dissimilar in nature.