birding-aus

Taxonomic Rethink in the Wings

To: Birding Aus <>
Subject: Taxonomic Rethink in the Wings
From: knightl <>
Date: Sun, 12 Dec 2004 17:24:39 +1000
http://www.newscientist.com/news/news.jsp?id=ns99996762

Birds of a feather not related to each other
09:30 11 December 04

If it walks like a flamingo and looks like a flamingo, it is not
necessarily a flamingo - or even a close relative. A controversial
genetic study suggests we have completely misunderstood how the
majority of birds are related, and that some species that look almost
identical are not related at all.

The discovery comes from an analysis of the evolution of the bird gene beta-fibrinogen . It suggests that the Neoaves, a group that includes
all modern bird species except waterfowl, landfowl and flightless
birds, actually comprises two distinct lineages called the Metaves and Coronaves, and that many birds which look alike are not in the same
lineage.

For instance, flamingos and roseate spoonbills - two pink, long-legged wading birds with similar-looking heads, wing shapes and plumage - are not related as previously thought. Flamingos, it turns out, belong to
the Metaves, while spoonbills belong to the Coronaves.

Matthew Fain and Peter Houde at New Mexico State University in Las
Cruces, US, analysed the number of different nucleotides found on
beta-fibrinogen across some 150 bird families. From that the
researchers constructed a new avian evolutionary tree.

Convergent evolution

They found two major lineages, each of which contains many examples of convergent evolution, the process by which two species that do not
share a recent evolutionary history nevertheless end up looking alike
and inhabiting a similar ecological niche.

Both lineages contain owl-like nocturnal predators, birds with long
curvy beaks that live on nectar, broad-winged oceanic divers and birds that evolved splayed toes to help them live in trees. Using this
classification, boobies and tropicbirds, two similar-looking types of
seabird, now belong to Coronaves and Metaves, respectively.

“People have been trying to classify birds based on their appearance for hundreds of years. It is valuable at some levels, but when you get to really deep divergences, you just hit a wall,” Houde says.

But Joel Cracraft at the American Museum of Natural History in New
York, US, is not convinced. “The base of modern birds is a very
difficult problem to resolve. This is a welcome data set, but it’s not going to be this simple,” he says. Fain and Houde are working with 11 other genes to corroborate their results.

Journal reference: Evolution (vol 58, p 2558)

--------------------------------------------
Birding-Aus is now on the Web at
www.birding-aus.org
--------------------------------------------
To unsubscribe from this mailing list, send the message 'unsubscribe
birding-aus' (no quotes, no Subject line)
to 


<Prev in Thread] Current Thread [Next in Thread>
  • Taxonomic Rethink in the Wings, knightl <=
Admin

The University of NSW School of Computer and Engineering takes no responsibility for the contents of this archive. It is purely a compilation of material sent by many people to the birding-aus mailing list. It has not been checked for accuracy nor its content verified in any way. If you wish to get material removed from the archive or have other queries about the archive e-mail Andrew Taylor at this address: andrewt@cse.unsw.EDU.AU