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Thursday, July 30, 2009

Common descent, uncommon descent, and, hey, a ladder into ...

A while back, I wrote to a correspondent about the infant grasping reflex.

He had written to say that some Darwinist somewhere was fronting the ability of human infants to hang on a couple of minutes as evidence of common descent with chimpanzees, and wondered how I could possibly deal with this evidence. (Well, I guess it would buy the human infant a couple of minutes of life, right? Not an attractive prospect, in my view. Better look elsewhere for human survival.)

Look, I do not have a problem with common descent, until its advocates get up on their hind legs and start arguing for it. One gets some of the worst arguments in the world, fronted by vast academic paraphernalia - and, very often, implied threats if one doesn't agree thrown in.

Now, the story in question raised the question of what counts as evidence of common descent.

As a teenager, (I married when I was 20), I paid my way through school, net of scholarships, by looking after babies, toddlers, and other small children.

I am no expert, but I know a bit about such creatures. As I explained to my correspondent, the human infant does not use the grasp reflex primarily for hanging on to Mom, but primarily for stuffing any grasped object into its mouth.

This makes sense from the human infant's perspective, of course. While the child can recognize mom's voice before birth, her voice is mainly a source of reassurance, not information.

Eyesight is a very great benefit for a child - once he can distinguish the boundaries of one item from another. The first thing most kids learn to distinguish is smiles, which they begin to copy, typically around 6 to 8 weeks of age. Experts differ as to whether the child really reciprocates affection or is merely copying a routine.

I have no learning to justify entering this controversy, so let me note only note that, whatever may be the case with the child, millennia of humans have seen the results and said., "See! He knows I am his dad and I am so very proud of him!" or "She's my little princess! Just see how she smiles at me!" So the human race goes on.

It is curious that - if some expert opinion is true - the child is programmed to act like he knows what is happening before he does, because adults notice and react favourably.

Anyway , I told my correspondent,
Claims about common ancestry should be founded strictly on genome mapping, NOT on behaviour.

Behaviour is simply NOT a reliable guide. Closely related life forms can have different behaviour - and life forms too distantly related to shed any light on each other can have similar behaviour because the behaviour is a necessary adaptation for the life they must pursue.

For example, opossums and koalas have offspring that cling to their mothers, but because they are marsupials, no one suggests that it demonstrates anything about close common ancestry with humans or other placental mammals.

Accounts of similar behaviour may feel good to the already convinced, but, as an enterprise in the serious study of evolution, this sort of thing is doomed to failure.

If the human and chimpanzee genomes overlap about 70-76% (a reasonable figure – forget the 98-99% chimpanzee hype), that suggests common ancestry as a reasonable probability, given other similarities. Also, there are apparent “errors” (e.g. Vitamin C pseudogene) that appear in both genomes, which adds strength to the argument. For example, ID advocate Mike Behe talks about the Vitamin C pseudogene in Edge of Evolution, as evidence for common ancestry.
I don't know. I just follow the story, unlike the pundits who KNOW.

If you follow me on Twitter, I'll let you know when I have posted a number of stories to one of my blogs, generally about 5 new ones.

Find out why there is an intelligent design controversy:


Podcasts in the intelligent design controversy

1. Intelligent Evolution and Darwin's Rival

Click here to listen.

On this episode of ID the Future, Casey Luskin talks with historian Michael Flannery for the third and final installment of this series on Alfred Russell Wallace and Flannery's new book, Alfred Russel Wallace's Theory of Intelligent Evolution: How Wallace's World of Life Challenged Darwinism.

Wallace lived a century ago — how is it fair to call Wallace a seminal figure for intelligent design? Listen in as Michael Flannery explains that while we cannot judge Wallace by the standards of today, we should view him as a man who took the latest ideas of science and drew “one fundamental conclusion: that certain features of the universe and of living thing are best explained by an intelligent cause and that an undirected natural selection was inadequate explanation for many key aspects of biological life."

Flannery also discusses how Wallace most closely resembles ID theorist Michael Behe in his acceptance of common descent and skepticism that the Darwinian mechanisms of chance and utility are capable of explaining everything in nature.

Michael Flannery is Professor and Associate Director for Historical Collections at the Lister Hill Library of the Health Sciences at the University of Alabama at Birmingham. He has previously published on Alfred Russel Wallace in Forbes Magazine online, and his book is published by Erasmus Press.

Click on the links below if you missed the first installments of this series:

Part One
Part Two

Darwinism and popular culture: Well, aren't we all 30 per cent banana anyway?

Just getting back to real work, and clearing out my in tray:

Friend Nancy Pearcey writes to note:

A policeman can be fired for calling a black man a "banana-eating jungle monkey."

But a scientist can be fired for not calling Man a "banana-eating jungle monkey."

The former penalizes people for their racism; the latter penalizes people for their lack of evolutionism.

A bit odd, don't you think?

After all, if the evolutionary picture is the whole show, is not Mankind per se a "banana-eating jungle monkey"? Or at least a close cousin?

Racism is evil.

But we learn that from our true Creator. Not from nature.

Not from an impersonal, indifferent cosmos.
Okay, fine, but years ago, a learned rabbi pointed out that we all share 30 percent of our genes with a banana, give or take a few here and there, so ...

I don't know what I would do without learned rabbis.

Hey, if you follow me on Twitter, I'll let you know when I have posted a number of stories to one of my blogs, generally about 5 new ones.

Find out why there is an intelligent design controversy:

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