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Old 03-04-2014, 09:45 AM   #6
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Default Re: Cool Science Stuff

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Originally Posted by FanSince72 View Post
Interesting article.

It may attempt to explain some things about evolution and appears to lean on the "Quantum Entanglement" theory as its basis, but it (as well as many other evolutionary theories) still has a ways to go to explain specific and relevant evolutionary processes.

One of the things that has always been missing from scientific explanations about evolution is the connection between "need" and development.

For example, in many dissertations on evolutionary development of monkeys, it is said that they began as small mammals who took to the trees for safety from larger predators. These animals ate the leaves, soft stems and insects in those trees.

But living in trees required use of all of their arms and legs to keep them from falling and they are said to have thus developed tails to allow them to securely anchor their bodies leaving their hands free to gather food.

But the thing that never seems to get explained is HOW this came to be.
Developing a tail was surely an advantage but what caused the tail to emerge?
Even if a prehistoric mammal could have thought that such an appendage would be useful, I doubt it simply willed it into existence. So much of evolutionary science explains "after-the-fact" conditions such as "having a tail allowed them to exist in the trees...., etc., but very few touch on what occurred prior to such development and what specifically triggered that development.

Then there's the issue of time.
Surely a tail did not develop overnight and probably took hundreds of thousands or possibly millions of years to develop, so what did these animals do in the meantime?

Perhaps theories such as the one you posted will begin to shed some light on such development and I suspect that if this theory proves useful, the notion of "willing" something into existence may not be so far-fetched.
The mammals from which the monkeys evolved also had tails. The precursors to mammals had tails.

Nothing triggers the mutations for a purpose. It's entirely random. Mutations that have no use or are detrimental, don't survive. Those that help are naturally selected.

Evolutionary change is stuck with the prior structures. It can never go back to the drawing board. Consider recurrent laryngeal nerve in mammals. It takes a very circuitous course, looping from the brain stem down around the aorta and then back up to the larynx.

Quote:
One of nature’s worst designs is shown by the recurrent laryngeal nerve of mammals. Running from the brain to the larynx, this nerve helps us speak and swallow. The curious thing is that it is much longer than it needs to be. Rather than taking a direct route from the brain to the larynx, a distance of about a foot in humans, the nerve runs down into our chest, loops around the aorta and a ligament derived from an artery, and then travels back up to connect to the larynx. It winds up being three feet long. In giraffes the nerve takes a similar path, but one that runs all the way down that long neck and back up again: a distance fifteen feet longer than the direct route! When I first heard about this strange nerve, I had trouble believing it. Wanting to see for myself, I mustered up my courage to make a trip to the human anatomy lab and inspect my first corpse. An obliging professor showed me the nerve, tracing its course with a pencil down the torso and back up to the throat.

This circuitous path of the recurrent laryngeal nerve is not only poor design, but might even be maladaptive. That extra length makes it more prone to injury. It can, for example, be damaged by a blow to the chest, making it hard to talk or swallow. But the pathway makes sense when we understand how the recurrent laryngeal nerve evolved. Like the mammalian aorta itself, it descends from those branchial arches of our fishlike ancestors. In the early fishlike embryos of all vertebrates, the nerve runs from top to bottom alongside the blood vessel of the sixth branchial arch; it is a branch of the larger vagus nerve that travels along the back from the brain. And in adult fish, the nerve remains in that position, connecting the brain to the gills and helping them pump water.

During our evolution, the blood vessel from the fifth arch disappeared, and the vessels from the fourth and sixth arches moved downward into the future torso so that they could become the aorta and a ligament connecting the aorta to the pulmonary artery. But the laryngeal nerve, still behind the sixth arch, had to remain connected to the embryonic structures that become the larynx, structures that remained near the brain. As the future aorta evolved backward toward the heart, the laryngeal nerve was forced to evolve backward along with it. It would have been more efficient for the nerve to detour around the aorta, breaking and then re-forming itself on a more direct course, but natural selection couldn’t manage that, for severing and rejoining a nerve is a step that reduces fitness. To keep up with the backward evolution of the aorta, the laryngeal nerve had to become long and recurrent. And that evolutionary path is recapitulated during development, since as embryos we begin with the ancestral fishlike pattern of nerves and blood vessels. In the end, we’re left with bad design.
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