[__ Science __ ] Do All Human Bodies Host “5 Traces of Ancient Species”?

[AIG.com]

A recent article highlighting homology claims every person today has five traces of ancient species in their bodies today.

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[BeyondET]

The human body host around 10,000 different species.

 

[Barbarian]

AIG misses it again, confusing analogous organs with homologous organs:

"So is homology really evidence for evolution? Well, it’s true that, if all of life did share a common ancestor, we’d expect to find similarities. But it’s likewise true that if all of life had a common Designer we’d expect to see similarities—after all, engineers don’t “reinvent the wheel” every time they make something! "

For example, a broad pelvis is actually uniquely human, the result of larger skull sizes in the birth canal. It has nothing to do with being upright. But our backs and knees show the evidence of us evolving from quadrupeds. How so?
The mammalian spine is well-adapted to a horizontal life. But not so much for a vertical one. Stacked upright, the spine puts huge forces on the lumbrosacral joint, which fails in a large number of humans, often causing permanent disability and pain. The lumbar curve is a modification that only partly alleviates the defect.

If one designed a human spine from scratch, it would not position spinal nerves so as to become entrapped and damaged if a vertebral disk were to blow out. But because humans did evolve from other primates, this is the structure we inherited and it was not possible to re-route nerves around the spine so as to avoid this. There is just no intermediate form that would work.

Effective walking requires a repositioning of the femur to angle inward, giving humans a slightly knock-kneed posture. It is biomechanically efficient for walking, compared to the rocking gait we see when chimps walk upright. But it puts huge pressures on the ligaments of the knee, which frequently fail under the stress. It is a particular problem for women athletes, presumably because wider pelvises will result in even greater stresses. I have two two daughters who played soccer avidly and went on to play in college. They both have had knee problems. I have son who still plays hockey in his 50s. And he had to have knee surgery. It just isn't a very good adaptation.

The homologies that show evolution also involve what we might consider to be good design. The wings of birds are biomechanically efficient in a way that adapted the upper limb structure of bipedal theropod dinosaurs to flight. Not surprisingly, the wings of bats work differently, but are biomechanically efficient in a way that adapted the upper limb structure of quadrupedal mammals to flight. Wings of birds and bats are analogous structures, but they are not homologous with regard to the taxa from which they evolved. Which is an important point. They are homologous with regard to primitive amniotes, from which mammals and dinosaurs evolved. Contrary to AIG's assumptions, not all tetrapods had ten digits.

The most significant finding about these tetrapods was the number of digits on their front and hind limbs: anywhere from 6 to 8, a strong indication that they couldn't have been the ancestors of later five-toed tetrapods and their mammalian, avian, and reptilian descendants... Among the notable post-gap tetrapods are the tiny Casineria, which had five-toed feet

They Came From Beneath the Sea: The First Tetrapods

About 400 million years ago, a fish with primitive lungs and stumpy limbs climbed out of the water and onto dry land. Learn about the first tetrapods.

www.thoughtco.com