For those of you having problems with the link provided in the last email,
try copying and pasting it into your browser. That worked for me. If all
else fails, read what I read below:

Time to update taxonomy?
8 January 2003
by Henry Nicholls

Taxonomy is stuck in the 18th Century, claims Canadian zoologist Paul
Hebert, who calls for a molecular revolution. "There is no more likely death
of a discipline than the failure to innovate," he warns.

With the right funding and support from the taxonomic community, Hebert,
professor of zoology at the University of Guelph, predicts that using DNA to
identify and help categorize new species would make a complete inventory of
life a feasible goal in as little as 20 years.

Traditionally, species have been identified and categorized on the basis of
morphological differences, but parts of the academic community are becoming
increasingly concerned that "morphological taxonomy", pioneered by Linnaeus
in the 1750s, is no longer equipped to account for the extent of earth's
biodiversity, frequently estimated at between 10- and 15-million species.

"Let's face it, the morphological approach has had 250 years to advance the
task, and we're only 10% of the way towards the goalposts," Hebert told
BioMedNet News. His solution, to which many taxonomists are strongly
opposed, is to distinguish between species on the basis of similarities and
differences in their DNA.

A DNA-based taxonomy would vastly accelerate the final inventory of life,
says Hebert. Each novel organism would be described rapidly and simply by a
"barcode" - a number that corresponds to a sequence of its DNA. Hebert
envisages this "gene species" as a first, mandatory step towards describing
a real species. At a later stage, traditional taxonomists could make the
formal morphological description of the specimen, which would then become
associated with its DNA barcode, he suggests.

Although most taxonomists support a role for DNA in taxonomic research, some
have expressed strong concerns about any move that would make DNA sequencing
a mandatory step in the description of a new species.

Many think that describing a species using DNA is expensive and unnecessary.
"In most instances, a quick survey of morphology will serve the same
purpose," write Ole Seberg, professor of evolutionary botany at the
University of Copenhagen in Denmark, and colleagues in a letter to be
published in the February issue of Trends in Ecology and Evolution (TREE).

There is also concern that a DNA-based taxonomy would exclude those in the
developing world, who have limited access to sequencing technology. "It
would disenfranchise a large fraction of the taxonomic community," warns
Charles Godfray, professor of evolutionary biology at Imperial College in
London and director of the country's Centre for Population Biology. Godfray
propelled the idea of a "taxonomic crisis" into the public arena in a
commentary published last year in the journal Nature.

Another fear is that turning taxonomy into a molecular science will drain
precious funds from what is already a desperately impoverished discipline.
"Training more taxonomists is a better use of resources than DNA taxonomy,"
said Diana Lipscomb, professor of systematics at George Washington
University in Washington D.C., whose criticism of a DNA-based system also
appears in TREE. "Experts, not sequencing technicians, are needed to help
complete the incredible challenge of documenting the earth's species in the
next few decades," she told BioMedNet News.

There is also concern about the accuracy of DNA data, with fears that
problems aligning sequences could introduce glaring errors into any database
that attempted to provide a molecular account of life.

However, Hebert believes that research he recently published in the
Proceedings of the Royal Society of London Series B provides compelling
evidence that DNA can be a reliable character on which to base taxonomic
description.

By analyzing just the sequence of the gene that encodes mitochondrial
cytochrome c oxidase I in a group of 200 lepidopterans, Hebert and his
colleagues successfully distinguished between the different species with
100% accuracy. Furthermore, the phylogenetic tree they produced based on
differences in this gene sequence corresponded very closely with the
phylogeny produced by conventional morphological means.

Nevertheless, several researchers remain uneasy about using a single feature
to identify species. "The molecular biology [of a species] is just a
particularly valuable set of character states ... perhaps the most important
set of character states, but it's not all there is," said Godfray. Lipscomb
goes further: "There is no credible reason to give DNA characters greater
stature than any other character type," she writes.

But Diethard Tautz, professor of genetics at the University of Cologne in
Germany, who has also contributed to the ongoing debate in TREE, believes
that he does have a credible reason. "Morphological structures ... will
often require new terminology and a lot of personal experience to identify
them unequivocally," he explained, whereas "DNA characters are universal,"
he told BioMedNet News.

Hebert also has a coherent counter-argument to each of the concerns raised
against the DNA-based world that he and Tautz are proposing. "I'm not
surprised to find that people are getting shirty about it," he said. "To
some extent, this is shaking the foundations of a tradition that's probably
the oldest and noblest tradition in biology."


Related links on other sites:
Paul Hebert Laboratory
http://www.uoguelph.ca/~phebert/

Bruce G. Livett PhD
Reader in Biochemistry and Molecular Biology
University of Melbourne,
Victoria, AUSTRALIA 3010
Phone: +61-3-8344 5911 / 5920
Fax: +61-3-9347 7730
Email: [log in to unmask]
Home: 48 Nicholas St. Ashburton, Victoria 3147, Australia
Email: [log in to unmask] (home)
Cone Shells: http://grimwade.biochem.unimelb.edu.au/cone/
==========================================
Nature Science Update: http://www.nature.com/nsu/020715/020715-11.html

----- Original Message -----
From: "BioMedNet" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Saturday, January 11, 2003 3:05 PM
Subject: A Message from Bruce Livett


> Personal message:
> Time to update taxonomy?  Take a look at this link on BioMedNet from
> 8 January 2003
> by Henry Nicholls
> Taxonomy is stuck in the 18th Century, claims Canadian zoologist Paul
Hebert, who calls for a molecular revolution. "There is no more likely death
of a discipline than the failure to innovate," he warns.  Enjoy the read :)
BGL
>
> The following Special Report has been sent to you by Bruce Livett
<[log in to unmask]>.
>
> -----------------------------
> Time to update taxonomy?
> 8 January 2003
>
> Taxonomy is stuck in the 18th Century, claims Canadian zoologist Paul
Hebert, who calls for a molecular revolution. "There is no more likely death
of a discipline than the failure to innovate," he warns.
> -----------------------------
>
> To read the full article, click the link below, or cut and paste the
entire link into your browser.
>
http://news.bmn.com/friend/80973eea7d/%2Fsreport%2Fprevious%3Fday%3D030109%2
6story%3D1