Imagine you’re a columnist. You decide to write something about how the National Park Service is allowing a creationist book to be sold in their Grand Canyon stores, over the protests of its own geologists, who point out that NPS has a mandate to promote sound science. Hawking a book that claims that the Grand Canyon was carved by Noah’s Flood a few thousand years ago is the polar opposite of this mandate. So what do you write? Well, if you’re Republican consultant Jay Bryant, and you’re writing for the conservative web siteTown Hall, you declare that this as a clear-cut case of Darwinist atheists censoring freedom of speech in a desperate attempt to squelch Intelligent Design.
The Australian media are doing a fantastic job of keeping up with the developments with Homo floresiensis. Here’s the first three-dimensional reconstruction I’ve seen of the little hominid, made by an Australian archaeologist. It’s published on the Australian Broadcasting Corporation’s web site. I’m sure that as more bones emerge, the image will improve, but this is still a wonderful first look.
Homo floresiensis update: The Economist weighs in on the “borrowing” of the fossils. They mention that when the bones were removed, they were simply stuffed in a leather bag. This is not exactly the sort of procedure you see in protocols for avoiding contamination of ancient DNA. In the Australian, the discoverers of “Florence” vow to return to the fossil site, and this time they’ll put their discoveries in a really good safe. Wise move.
The New York Times, December 7, 2004
Scientists have used computer analysis to read evolution backward and reconstruct a large part of the genome of an 80-million-year-old mammal. This tiny shrewlike creature was the common ancestor of humans and other living mammals as diverse as horses, bats, tigers and whales.
Actual DNA molecules cannot survive such lengths of time. Mammal fossils from this period are extremely rare. But by tracking the course of mammalian evolution, scientists can pinpoint when a common ancestor existed and what, in general terms, it was like.
Continue reading “When Bats and Humans Were One and the Same”
In tomorrow’s New York Times, I have an article about how to reconstruct a genome that’s been gone for 80 million years. The genome in question belongs to the common ancestor of humans and many other mammals (fancy name: Boreoeutheria). In a paper in this month’s Genome Research, scientists compared the same chunk of DNA in 19 species of mammals. (The chunk is 1.1 million base pairs long and includes ten genes and a lot of junk.) The researchers could work their way backwards to the ancestral genetic chunk, and then showed they could be 98.5% certain of the accuracy of the reconstruction.