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12.29.2011

Human Evolution: Adapting to Adaptation

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I just finished watching a NOVA series about human evolution. It wasn't particularly well produced, but it was very informative. Pre-humans Homo erectus and Homo neanderthalensis (aka Homo heidelbergensis, because the ancestors of Neanderthals were found near Heidelberg, Germany) migrated out of Africa before Homo sapiens had evolved in Africa. Actually, to be clear, only Homo erectus actually migrated out of Africa, then the population that settled in Europe evolved into the Neanderthals as they adapted to the more temperate climate (they had to deal with winter). As an aside, a population of Homo erectus that made it to Indonesia evolved a smaller stature and today it is referred to as a species of "hobbit," although it is not the hobbit of J.R.R. Tolkien fame.

The remaining population of Homo erectus in Africa experienced dramatic climactic shifts (mainly drought) that reduced the population almost to extinction, but one small coastal population adapted to sea life and became the ingeniously tool using and enterprising Homo sapiens.

The Homo sapiens population grew and then also started migrating along the same geographic paths that earlier Homo erectus had taken up through the Middle East, then spreading into Europe, Asia, Indonesia, and eventually even to Australia (it's not clear that Homo erectus ever made it as far as Australia). Homo sapiens was a lot more crafty and technologically savvy. It would be nice to think that we interbred with Neanderthals and/or Homo erectus when we encountered them already living in Europe and Asia, but the available genetic evidence suggests we didn't (no shared genetic fingerprints to date).

So we probably either out competed them for resources or killed them off or drove them out, until they had no where left to go and died off. It sounds a lot like how humans act towards outsiders today. Maybe we can evolve ourselves away from that using our other great adaptation - CULTURE.

Because evolution is still going, and that means humanity can still evolve and adapt and improve. But it also means if we don't use the brains that nature gave us, we might go extinct from our own technological excesses. We are the first species that has ever had to adapt to its own adaptiveness.

As a distinct species, we are only about 200,000 years old, tops. Virtually embryonic. Granted, we have done a lot in the time allotted.

I think the human brain size is still growing. As an aside, I know that my own skull is gigantic, as evidenced by the rarity of hats that will fit my head. However, my individual Darwinian fitness is questionable. I may be too smart for my own good. But that's for the process of natural selection to decide (noting that it does not consciously decide anything in a rational way; that is but a figure of speech).

12.26.2011

Everything You Wanted to Know About Evolution and Then Some

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If you read "The Greatest Show on Earth" by Richard Dawkins and still don't believe in evolution by natural selection, you are without a doubt being willfully ignorant and self-deceiving.

If on the other hand you do not read "The Greatest Show on Earth" by Richard Dawkins BECAUSE you don't believe in evolution, then may God have mercy on your soul.

Regardless of your particular circumstance, I do not wish to debate you unless you have read it. For those of you in the category of having read the book and reached the conclusion that evolution by natural selection is obviously scientific fact, well, there is really nothing to debate (besides a few minutiae on the details) because we are in agreement.

This book is an in depth exploration of the scientific evidence for evolution, and it is airtight. It blasts every creationist fallacy out of the water with hard facts that are easily verifiable by anyone who cares to visit a natural history museum or even read a lay scientific journal every now and then.

Increasingly, I side with Dawkins that creationists are willfully self-deceiving and emotionally driven to elude the facts about evolution at all costs. Where it becomes really dangerous is when creationists, not satisfied to keep their religious beliefs to themselves, try to promulgate this scientific ignorance to others.

But anyone who reads this book will have the facts inescapably fire hosed into his or her face, eloquently and unapologetically. The outcome can only be one of two things - acceptance of evolution by natural selection as scientific fact or brutal self-acceptance of one's willful suspension of disbelief in creationism. The verifiable facts presented in this book leave no room for doubt. It is not speculation. He shows you the hard evidence for evolution (yes, even the fossils of the "intermediate species" that creationists refuse to acknowledge). You can, in most cases, touch the evidence and in all cases verify it with your own brain. To deny what Dawkins presents is to deny facts that Dawkins himself did not manufacture. He is just presenting hard scientific evidence gathered by many scientists over many years that irrefutably supports evolution by natural selection.

I was fascinated by the chapter on the evolution of humans. I already understood that humans did not evolve FROM chimpanzees (rather, chimps and humans both evolved from a common primate ancestor, no longer living, that had some features of both modern day species, but was not a chimp nor a human itself). Dawkins presented a fairly high level overview of the transitional species from Australopithecines (an upright walking primate with a chimp-sized brain) through primitive Homo species to modern Homo sapiens, but it clearly illustrated the concept of gradual change over time. Fossils "punctuate" the timeline between ancient primates and humans, because we do not have access to all the fossils of every primate that ever lived (if we did, we could see the gradual small changes from generation to generation). But the ones we do have are notable because even paleoanthropologists have a hard time classifying the fossils we have as one extinct species or another. This is because they have many features in common as well as some notable differences (largely in brain size, but there is overlap between the smallest brain of a more recent species and the largest brain of a more distant species, because of the natural variation, so sometimes it is difficult to decide).

One of the take home messages I got from reading the chapter on human evolution is that gradual change is very hard to discern. But we know that human beings have gradually changed just in the past few hundred years. We are generally larger in stature, and some might even argue intellectually more advanced as a species.

But when 40% of Americans still believe God created everything and the Earth is less than 6,000 years old, if the human species on the whole is really more intellectually advanced, then the other 60% of people must be REALLY intelligent to counterbalance the utterly ignorant.

In any case, all I know is that it is pretty miraculous and amazing that my evolutionary ancestors survived some 4.5 billion years from the first replicating organic molecules in the primal muck until now. You might think it is even more improbable and miraculous than some divine being putting everything together in seven days. But be that as it may, there is hard scientific proof for the miracle of evolution and that's good enough for my 1.3 liters of human brain matter.

12.24.2011

The New Testament Appears to be Largely Forged

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With the exception of some of Paul's letters, most of the books of the New Testament appear to biblical scholars to be forgeries by early Christian non-Apostolic authors.

There are a lot of good reasons for this, but the fact remains that most of the Apostles were completely illiterate and could not have penned the canonical books that bear their names. In addition, the originals were written in Greek, not Coptic or Aramaic, the languages that would have been spoken (but obviously not written) by Jesus and his Apostles. Often, they were anonymously authored and church fathers assigned the names of Apostles to them post facto.

It appears unknown Greek-speaking authors, 10-50 years after Jesus died, penned their versions of the events of Jesus' life (probably from traditional oral stories) and in some cases attributed them to an Apostle in order to give them "street cred." In other cases, church fathers attributed them to Apostles in order to allow them to be part of the Biblical canon.

Recall that the New Testament did not exist during the life of Jesus. It was compiled from 27 books of early Christian writings that came into existence after Jesus (and most of the Apostles) were long dead.

I have never liked publication bias. I do not like it in modern scientific research and I do not like it in the Bible, although there is very little I can do about it in either case.

Stay informed. Don't believe the hype.

12.19.2011

Common Ancestors

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My dad handed off his copy of Richard Dawkins' "The Greatest Show On Earth" to me yesterday. Naturally, I busted into it right away.

When you think about evolution (but first you need to know about it), you realize that any God worthy of the moniker would create and fully endorse a process like natural selection. It is so wonderfully simple and elegant and powerful.

One of the greatest points of confusion for unscientific and religiously deceived people is the idea that we evolved FROM chimpanzees. The fact is, we didn't.

Creationists try to use this argument to refute evolution, but it's a moot point, because no evolutionist claims we evolved from chimpanzees. Chimpanzees and humans exist today, so they could not have evolved from each other.

They evolved from a common ancestor that resembled a human and a chimp, but was actually neither. There was some point in time, millions of years ago, when a chimpy humanish looking beast branched into two lines of descent. One descendant population gradually changed over time, little by little, to become today's chimps. The other population of descendants gradually changed in a different way over time, to become today's humans. Today, the most human looking chimp and the most chimp looking human do not resemble each other very closely, but for some period of time after the point at which the populations branched from the common ancestor, the two evolving populations had a proportion of individuals that looked quite a lot alike (and a proportion that didn't).

Once you understand mathematical proportions and the idea of forks in the evolutionary road over long periods of time, evolution becomes almost common sense. At least I think so.

If you are a creationist or some other kind of non-believer in (or misunderstander of) evolution, I'd like to know what you think and what, if anything, still confuses you.

There's the false notion of random chance leading to the complexity of life, again largely used erroneously by creationists to refute evolution, but I think this is a non-issue. Natural selection is not a random process (although mutation can be). Natural selection is very non-random and biased. It "selects" for advantageous traits and kills off disadvantageous traits. That's not random. If it were, trait A would have no advantage over trait B, and evolution would not occur.

But since natural selection is "selective" by definition as a process, it is not random. So I really hope you are not one of those people who has been mislead into thinking evolution is a random process. If so, think about what I just said for 30 seconds and completely dispel the idea.

Better yet, read a Dawkins book (anathema!). He's quite knowledgeable on the subject, even if you don't care for his patronizing attitude toward creationists.