One fifth of the world's vertebrates are
threatened with extinction. That's the word from the 10th Conference of the
Parties to the Convention on Biological Diversity this week in Nagoya, Japan,
where a team of 174 scientists presented an assessment of the world's at-risk
vertebrate species.
According to the study, published in the October 28
issue of Science, the number of threatened species has grown dramatically in the
past four decades, exceeding the normal "background rate" of extinction by a
factor of two or three. The IUCN Red List of Threatened Species
currently lists 25,780 vertebrates as threatened, and an average of 52 species
become more threatened (based on the IUCN's categories of risk) every
year.
"The 'backbone' of biodiversity is being eroded," said Harvard
University entomologist Edward O. Wilson in a prepared statement. "One small step up the
Red List is one giant leap forward towards extinction. This is just a small
window on the global losses currently taking place."
There is small
amount of good news accompanying this study: The wide range of conservation
efforts around the world has actually slowed this rate of extinction.
But
current conservation efforts are far from adequate. According to a second study, also presented at the
conference and published in the same issue of Science, the world would
need to spend 10 times as much as it currently does on conservation in order to
halt the pending extinction of many species. "There is no question that
business-as-usual development pathways will lead to catastrophic biodiversity
loss," said one of the second study's lead authors, Paul Leadley of the
University of Paris?Sud, in a prepared statement. "Even optimistic
scenarios for this century consistently predict extinctions and shrinking
populations of many species."
The authors point out that all changes in
species population size and distribution matter, as they reflect the health and
well-being of the dominant species on the planet: humans. If species are dying
out, it is an indication of the long-term health of our own species, and we need
to be aware of the impact we are having on our own ecosystem.
http://www.scientificamerican.com/blog/post.cfm?id=extinction-crisis-revealed-one-fift-2010-10-27&sc=CAT_EVO_20101101
