January 12, 2005

NO MATTER HOW YOU JIGGLE AND HOW YOU DANCE THE DANG THINGS JUST WON'T SPECIATE:

Bones of contention: The discovery of a new species of human astounded the world. But is it what it seems? John Vidal went to remotest Flores to find out (John Vidal, January 13, 2005, Guardian)

If you want to understand human evolution, it may be worth starting with Johannes Daak from the remote village of Akel in the heavily forested centre of the Indonesian island of Flores. Johannes, from the Manggarai ethnic group, reckons he is 100 years old and says he owes his longevity and enduring strength to having only ever known one woman. He says he owes his stature to his ancestors.

Johannes is no more than 4ft 1in (1m 25cm) tall, give or take an inch. His grandfather and father were also tiny, and so is his son. All of them had "normal" sized mothers, but for some reason, only the males in his family seem to be small.

Next month, two researchers from Indonesia's leading Gadjah Mada University in Yogyakarta, will head to Akel and nearby Rampasasa villages to measure Johannes's family and other "little" people who live there. The size and proportions of their limbs and skulls will then be compared with those of the most celebrated skeleton in the world - Homo floresiensis, aka the Hobbit, the little lady of Flores, ebu, or, in the shorthand of the scientists who found the skeleton in a Flores cave called Lian Bua, LB1.

This 13,000-year-old, 1m tall, 25-year-old hominin with a brain one-third the size of modern man's, was found just a few miles from Johannes's village and was a scientific sensation last October when the team of Australian and Indonesians that unearthed it claimed in the journal Nature that it was an entirely new human species. Dubbing it Homo floresiensis and nicknaming it hobbit, they said it was a descendant of a long-extinct ancestor of modern man (Homo erectus), thought to have flourished between 1.8m and possibly 300,000 years ago. Dubbed one of the breakthroughs of 2004 by US journal Science, it made worldwide news.

Fossils show only about 10 human species and 50 sub-species, so finding a brand new one is a huge story for anthropologists, and Homo floresiensis was greeted as the most breathtaking and important discovery in 150 years, changing our understanding of late human evolutionary geography, biology and culture. It was not only the smallest adult hominid found, but the Australian team even suggested that because it came so late in the human evolutionary scale, a group of Homo floresiensis could be alive today in the forests of Flores.

But every major find has a backlash, and in this case a fierce, high-level challenge has come from academics in several countries. Leading them is Professor Teuka Jacob, who heads the Laboratory of Bioanthropology and Paleoanthropology at Gadjah Mada. The only man outside the excavating team to have inspected the skeleton, Jacob says it is conceivable that Johannes' family are descendants of the Little Lady of Flores.

But even if his researchers find no direct link, he says he is certain from his own preliminary inspection that the bones now locked in a safe in his vault at the university do not belong to a new species within the genus homo, or even a sub-species, but a pygmy version of Homo sapiens - not unlike Johannes.

And he claims that behind the intense media attention last October were ill-equipped, hurried young academics whose work was not properly scrutinised.


Has any Darwinist claim ever withstood serious examination?

Posted by Orrin Judd at January 12, 2005 10:51 PM
Comments

Well, yes, particulate inheritance.

Now you're going to tell me that isn't how it works, no?

Posted by: Harry Eagar at January 12, 2005 11:46 PM

No, that it isn't Darwinian.

Posted by: oj at January 13, 2005 12:02 AM

That the environment shapes and culls pre-existing genotypes rather than creating those genotypes (e.g., Lamarkism is wrong).

Posted by: Annoying Old Guy at January 13, 2005 9:55 AM

AOG:

Yes, that's the chief claim that doesn't withstand scrutiny.

Posted by: oj at January 13, 2005 10:06 AM

Big picture, I'm with you (because/and it makes the most empirical sense to me) that God created the various beasts of the field (and, separately, us). But my view on how all this happened is perhaps my least consistent opinion over the course of my 29 years.

Regarding speciation: what about wolves and dogs? Isn't that speciation?

Posted by: rds at January 13, 2005 12:20 PM

rds: By the classical test for separate species (can't produce fertile offspring), no. Wolf/dog hybrids are usually fertile.

Posted by: joe shropshire at January 13, 2005 12:27 PM

indeed, Darwin's famed finches, once thought to have speciated, can crossbreed fine, they just don't. Nothing speciates due to natural selection.

Posted by: oj at January 13, 2005 12:32 PM

When you say "nothing speciates due to natural selection," does that mean that speciation can occur in other ways?

I suppose it is possible to define out of existence the possibility of speciation through cross breeding, because where it is possible (between dissimilar animals that produce fertile offspring like wolves and dogs) it is automatically not speciation.

Posted by: rds at January 13, 2005 1:07 PM

Speciation has occurred, but it seems Natural Selection is not the process by which it does.

Posted by: oj at January 13, 2005 1:21 PM

rds: if a male and a female can reliably produce fertile offspring then they're similar, not dissimilar, even if they don't look it. Here's the Wikipedia article on species. There are several definitions, of which the biological or isolation species is the most rigorous. Morphological classification isn't as reliable : biologists often did and occasionally still do make mistakes -- what were thought to be distinct species based on morphology turn out to be just varieties. In paleontology, morphology's all you've got to go on. That's reason enough for an interested layman to be skeptical of the latest headlines. Wolves and dogs are classified separately (canis lupus, canis rupus , etc. vs. canis familiaris ) and are distinct species under one definition on offer, the mate-recognition species (wild wolves rarely breed to dogs), but not really under the strictest definition (cross breed fertility's pretty good, genetic variance is about .2%, same number of chromosones, same number of nucleotides on each. ) Horses and donkeys are distinct species (different number of chromosones, for starters) even though there is, very occasionally, a fertile hinny (girl mule.) Bottom line is that there are areas of dispute, and that goes double with extra cheese for the human fossil record.

Posted by: joe shropshire at January 13, 2005 3:04 PM

Hence the frequency of out-and-out extinction. I'm curious what example you would give of two current species that you recognize to have speciated from a common ancestor though means other than natural selection.

Posted by: rds at January 13, 2005 3:08 PM

rds:

Presumably all species share common ancestors but speciation has occurred by other means than Natural Selection.

Posted by: oj at January 13, 2005 3:19 PM

Joe: I didn't expect such a useful entry from wikipedia. Thanks for that.

I didn't know about the fertile hinnies. Presumably over a few million years, it might occur that a geographically isolated population of horses and donkeys produces a few fertile hinnies, which in turn mate with some horses . . . until something new arises. But is it your view that it has never been documented that the "something new" in that circumstance eventually morphed into an animal that could no longer productively mate with pure representatives of its horse ancestors if such could still be found?

I'm still not clear on what speciation oj (or you) acknowledge and what you don't (and oj cryptically returns to this topic often enough that I'm curious where and why he draws his lines.

Posted by: rds at January 13, 2005 3:27 PM

oj: I'll stop pestering. But I'm not sure how you can tell (given the passage of millions of years) that natural selection has never caused the creation of a new species. If the hinnie-spawn in my above example happen to be better adapted to climbing along the edges of precipices because they startle less easily than horses, and their horse bretheren go extinct because the human inhabitants of the area hunt well on the open plain but not well on the edges of precipices and the hinnie-spawn survive for that very reason, I view that as the operation of natural selection (lots of hinnie spawn still around, no horses). I also see that as likely to have occurred sometime in the distant past. Maybe you've got a narrower definition of natural selection?

Posted by: rds at January 13, 2005 3:35 PM

Hm. I realize that I still don't have a new species created by natural selection, I just have one outlasting another.

Posted by: rds at January 13, 2005 3:43 PM

rds:

That's right, we can't rule out its ever having happened.

Posted by: oj at January 13, 2005 3:53 PM

rds:

Your hinnie spawn is still a horse.

Posted by: oj at January 13, 2005 3:53 PM

yes, still a horse in my example. I take your point that the phenomenon has not actually been observed, but cannot be ruled out.

Posted by: rds at January 13, 2005 3:59 PM

I thought Natural Selection only explained extinction.

Posted by: Jeff Guinn at January 13, 2005 7:03 PM

Jeff:

It doesn't explain that either.

Posted by: oj at January 13, 2005 7:30 PM

Natural Selection explains reproductive fitness. Extinctions are occasional artifacts of that.

Orrin will have to cite a predarwinian prediction of particulate inheritance or convict himself of the most stupid statement he's ever made about darwinism, which is saying something.

Posted by: Harry Eagar at January 14, 2005 8:39 PM

Well, particulate inheritance is Mendelian, not Darwinian, for one thing. Darwin was a blended man. For another, there's no evidence that evolution proceeds by particulate inheritance.

Posted by: oj at January 14, 2005 11:50 PM
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