Friday, May 7, 2010

Family Tree

One of the difficulties with most theories of human evolution is that they assume that many of the alleged early hominids were members of different species, and that each of these species gradually gave way to another over millions of years on the way to producing modern man.

The problem is that the concept of a species is so nebulous as to be almost useless in these speculations. The textbook definition of species is a reproductively isolated population. In other words, if members of two disparate populations are unable, for whatever reason, to produce fertile offspring they are said to be reproductively isolated and thus belong to different species.

This definition entails that organisms isolated by geographical, physical, behavioral, or even temporal factors would be different species even if they were genetically compatible. Two individuals would be reproductively isolated if they were separated from each other by either distance or time (as are members of different generations of humans), or if they were physically incompatible, or if behavioral idiosyncrasies prevented synchronization of mating cycles.

This being the case it's a little absurd to think that just because two different hominids were physically different and/or lived at different times that they were therefore different species, but that's the assumption that's almost always made in the study of human evolution. Now, however, comes a story in the New York Times that bodes ill for this assumption. The report explains that indeed two different lines of hominids actually did interbreed and, though the Times never draws this conclusion, were thus conspecific:

Neanderthals mated with some modern humans after all and left their imprint in the human genome, a team of biologists has reported in the first detailed analysis of the Neanderthal genetic sequence.

The biologists, led by Svante Paabo of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, have been slowly reconstructing the genome of Neanderthals, the stocky hunters that dominated Europe until 30,000 years ago, by extracting the fragments of DNA that still exist in their fossil bones. Just last year, when the biologists first announced that they had decoded the Neanderthal genome, they reported no significant evidence of interbreeding.

Scientists say they have recovered 60 percent of the genome so far and hope to complete it. By comparing that genome with those of various present day humans, the team concluded that about 1 percent to 4 percent of the genome of non-Africans today is derived from Neanderthals.

It's interesting that the implications of this discovery are not mentioned in the article which insists on referring to "human-Neanderthal" interbreeding as if Neanderthals were not humans. The fact is that if such unions produced viable offspring then Neanderthals were human, and if that's the case then there wouldn't seem to be much warrant for treating Homo habilis and Homo erectus as different species from H. sapiens.

RLC

Only in America

This may be very hard for those still in possession of their rational faculties to believe but five high school students were threatened with suspension by their high school administrators the other day because they wore T-shirts that sported an American flag and refused to turn them inside out. Why were they told to turn them inside out? Because it was Cinco de Mayo and the California school they attended has a large Mexican-American population, and the principals were afraid that the Mexican students would be insulted by the shirts, which, of course, some of them were.

Here's an excerpt from the news report:

But to many Mexican-American students at Live Oak High School, this was a big deal. They say they were offended by the five boys and others for wearing American colors on a Mexican holiday.

"I think they should apologize cause it is a Mexican Heritage Day," Annicia Nunez, a Live Oak High student, said. "We don't deserve to be get disrespected like that. We wouldn't do that on Fourth of July."

As for an apology, the boys and their families say, 'fat chance.'

"I'm not going to apologize. I did nothing wrong," Galli said. "I went along with my normal day. I might have worn an American flag, but I'm an American and I'm proud to be an American."

Let's understand. These were American kids in an American school paid for by American taxpayers, but they weren't allowed to wear an American flag T-shirt because it was offensive to Mexican-American students who came to this country ostensibly to be Americans, or so we're always told.

I wonder if the school also took down the American flags around campus so as not to offend the sensibilities of Mexican students. I wonder if they ran a Mexican flag up the flag pole that morning. I wonder if they recited the pledge of allegiance in their classrooms to start the day.

Can you imagine Mexican officials threatening Mexican students for wearing Mexican flags on their shirts on the Fourth of July in a school in which there's a sizable minority of American students? Me neither.

At any rate, the district administrators were apparently appalled by the poor judgment and shameless, abject political correctness of their building principals. In a move that must have been a considerable embarrassment to the principals the district overruled them:

The five boys and their families met with a Morgan Hill Unified School District official Wednesday night. The district and the school do not see eye-to-eye on the incident and released the following statement:

The district does not concur with the Live Oak High School administration's interpretation of either board or district policy related to these actions.

The boys will not be suspended and were allowed to return to school Thursday. We spotted one of them when he got to campus -- and, yes, he was sporting an American flag T-shirt.

At least someone in that district has some common sense.

RLC