Monday, April 15, 2013

What Darwin Didn't Know- Ch 1 -The Scope of Challenges - Part 5: The Problem of Intermediates - Pt 2


Book Cover: What Darwin Didn't Know
I dove into Geoffrey Simmons' "What Darwin Didn't Know" (2004), to evaluate an anti-evolution book.

I'm maintaining an index of my responses here.

Today's Chapter - 1: The Scope of Challenges - Part 5:  The Problem of Intermediates - Pt 2

My highlighter caught fire while highlighting every sentence in this next bit from "What Simmons Doesn't Know About Evolution." Frustrated, I hurled the highlighter across the room, and decided to just dive in.

Misconception 1: ALL the Permutations!

If humans truly had monkeys as prehistoric intermediates, shouldn't there still be, somewhere in the world, a remote family of humans that still walk on all fours, or a few folks with very long arms, or people who hang from and procreate in trees, or groups who still eat ticks found on their spouses?
I think I've identified yet another part of evolutionary theory Simmons doesn't get. Evolution doesn't produce every possible permutation between two species.

Let's say that "evolution-river theory" talks about how rivers/streams tend to branch apart, every once in awhile, so that the original river ends up being 8-10 small streams by the time it reaches the ocean. Simmons' objection here would be that "evolution-river theory" predicts that we should find all sorts of "partial rivers" that are currently in middle of solid rock, or up in trees, between two independent sub-streams, and since we don't find those, "evolution-river theory" is wrong, or has major problems.

Chimpanzees and bonobos (yes, spell checker, "bonobos" is spelled right, and no, it's not a misspelling of "nanobots") are still fairly tree-living. It's quite possible that our lineage, living in plains, and walking around up-right, emerged after we branched off from chimps 6-8 million years ago.

Why is that important? Here's a hint - something Simmons isn't getting or remembering here. Species tend to evolve as a group.

Flock of Birds
Courtesy Wikipedia - CC
If we make an analogy to flocks of birds (the cloud ones, not the V-shaped ones), the "average genetics" of the group tend to move around as a group, because they'll inter-breed and average out over time. When the Chimp/Human common ancestor split off, it'd be like that flock of birds splitting, and the two sub-groups flying off in different directions. Simmons' objection would be like pointing out that if it were true that the two currently independent flocks of birds came from a single group in the past, then why is it we don't see birds at intermediate points that are half-group A and half-group B, between the two flock positions, even if they're a hundred miles apart?

That's how deranged the objection comes across to those who understand how evolution works.

Let's gracefully segue from his question about spouses eating each other's ticks to his next bit.

Misconception 2: Misapplication of "survival of the fittest"

Shouldn't some humans have retained a hair coat?
Some have. If you're brave, click here for a Google Image Search of "hairy people".

Desmond Morris wrote that there are 193 living species of monkeys and apes, and that 193 are covered with hair. It seems odd that only one line requires parkas, gloves, and electric heating for chilly nights. Survival of the fittest should have enhanced those who had natural protection from the cold.
We have multiple problems with this argument.

First, as I pointed out before, that loss could have happened after we branched off, so of course it'd be isolated to our lineage.

Second, and probably more importantly, he's not understanding the influences of environment and history on the human lineage... as well as what would constitute a beneficial mutation. Let's build a possible narrative, where these problems he brings up would not be a problem under evolutionary theory (whether it's factually supported or not is another question, but I'll address that later).

Branching off from Chimpanzee Common Ancestors

Once our lineage branched off, it probably migrated into the plains of Africa. That's important, because the environment is different than those who stayed in the jungles.

There are far fewer trees, and far less fruit. Thus tree-climbing becomes a novelty, and other sources of food must be found, not to mention, new sources of defense, other than climbing the nearest tree.

We were already a social species at that point, so we had a tendency to work together for survival and defense.

Eating Animals

We weren't completely vegetarian, either, given that we apparently liked to (or needed to) eat bugs. With the fruit gone, there's another option - eating animals (delicious meat).

Not only would that satisfy most of our nutritional requirements, but big powerful brains need lots of calories, so this step was arguably an important step in our intellectual advancement. As an aside, this is a big reason why simply being smarter isn't advantageous enough for all creatures to evolve to be intelligent - consistent high-calorie food sources are a must (link to article about meat eating and bigger brains) (which is probably one reason why most predatory creatures are more intelligent than prey). Owning a supercomputer does not give you any advantages if you don't have the 20 kilowatts to power it.

Whether our arms got shorter, or our legs got longer, having arms that were too-long would be an impediment for running - which is something tree-dwellers don't have to do frequently. Additionally, our capacity to coordinate enough to start hunting larger animals, like elephants, rhinoceros or deer, meant that we needed to carry tools, like spears (which our larger meat-powered brains could then accomplish). We may have started on smaller animals, but this gave us access to significantly larger portions of food.

It starts to be easier to see how our current configuration might be advantageous in that environemnt, does it not?

Animal Skins

It doesn't take a genius tool-user to figure out that there's parts of the large animals, one's group has killed, that could be fashioned into more tools. It probably didn't take long until those skins, set aside from the animals, turned leathery, and our ancestors started wearing them to protect them from the rain... and found the practice broadly useful.

Hair/Fur is not a Pinnacle of Evolution

To have fur is arguably a necessity for those creatures who cannot create clothes. Once humanity's ancestors stated fashioning artificial protection, we no longer needed fur. It wasn't a question of random happenstance.

Fur isn't a perfect solution. First, one can't take it off if it gets too hot - and heat exhaustion is a potential problem.

Second, it's a massive hygiene problem.

Have you ever seen cats, mice, chipmunks, dogs, etc, licking/grooming themselves? No, it's not that they think their own fur is tasty. It's hygiene - a constant effort, where they must dedicate a considerable amount of time and energy into removing parasites and creatures from hiding in their fur, potentially giving them diseases - often fatal ones.

Let's put it this way - which is easier to clean, a smooth kitchen counter, or a nice thick rug? Having clear, smooth skin is much easier to clean/maintain than when it's covered with fur - and when we changed our biological environment where not having a fur coat didn't mean potentially freezing to death anymore, having fur actually became a detriment... where those who had fur were more likely to die from disease than those who didn't. Natural selection takes over, and disables that gene (which does sometimes get switched on in some people).

Plus, no more tick-eating.

So, no, fur is not a pinnacle of evolution that all creatures should have.

Once again, Simmons is using an example of evolution, that would actually confirm evolution, as a problem for evolution.

Unsupported Narrative

As I mentioned before, the above narrative is something I made up... probably. I may have pieced together disparate facts I know, and it may mostly turn out to be true.

Here's the thing - that's all I need to do to shoot down Simmons' arguments. His approach of "casting doubt" on evolution by asserting straw man characterizations of what it'd necessarily produce if it were true, is so tenuous, that all I have to do is point out a possible alternative that works within evolutionary theory... and his argument is shot to hell, because it relies on his assertions being the only possible outcome.

While my narrative is unsupported, Simmons's ignorance does not refute, or even cast doubt, on evolution.

Again, he doesn't know how to refute scientific theories.


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Okay, that's one more paragraph done. There's still more to this section. Maybe I'll get through it next time.


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