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Random Samples

Howdy all. 

>From a weekly Science emailing two interesting notes this morning:

Michael Patrick Corriss 

Random Samples
Volume 315, Number 5815, Issue of 23 February 2007
Â2007 by The American Association for the Advancement of Science.

NETWATCH: On The Hoof 

What does a dromedary camel loping across a sand dune have in common with a 
Lippizaner stallion high-stepping around a ring and a rhinoceros luxuriating in 
a mud puddle? They are all ungulates, mammals that typically sport the 
overgrown toenails known as hooves. To learn more about the group or individual 
species, drop by the Ultimate Ungulate page from Brent Huffman, a keeper at the 
Toronto Zoo in Canada.
Introductory pages summarize some of the surprises from recent molecular 
studies on mammalian evolution, which distanced the ungulates from elephants 
and aardvarks, long thought to be their next of kin. Hoofed animals are 
actually more closely related to bats. Species accounts cover most of the more 
than 250 ungulates, offering details on the animals' diet, habitat, behavior, 
and range.



Fifteen bird species have been newly discovered by a DNA identification 
technique called bar coding, researchers reported online 19 February in 
Molecular Ecology Notes. They've also uncovered six new bat species in bat-rich 

 A different bat.

The Barcode of Life project seeks to determine the DNA sequence of the same 
mitochondrial gene in millions of Earth's fauna. The variations in the sequence 
provide a unique, easy-to-read species identifier, scientists say.
Until now, bar coding hadn't been tested in either mammals or widespread bird 
populations. For the bird probe, evolutionary biologist Paul Hebert of the 
University of Guelph in Canada and colleagues cataloged DNA from 2500 specimens 
supplied by museums and bird banders in the United States and Canada. The 
samples represent 643 of the 690 known North America-based species. Bar codes 
supplied some surprises, revealing 15 "cryptic" species: birds so similar to 
other birds that they had not been seen as distinct. What's more, eight 
supposed gull species turned out to be just one, and birds from 14 other 
supposed species were virtually identical to at least one other species.

In the mammalian end of the project, Hebert's team turned to Guyana, taking 
tissue samples from 840 bat specimens in the Royal Ontario Museum. There was 
concern that the species would be too closely related to reveal genetic 
differences. Yet the researchers easily distinguished the 80 or so species in 
the collection and discerned several new ones, Hebert says. Such studies have 
the potential to "break bar coding" by proving to skeptics that species can't 
always be distinguished on the basis of just one gene, says project member Mark 
Stoeckle of Rockefeller University in New York City. "But it's worked 
everywhere it's been applied."