Posted on 01/02/2008 7:36:33 PM PST by blam
Giraffes And Frogs Provide More Evidence Of New Species Hidden In Plain Sight
Genetic subdivision in the giraffe based on microsatellites alleles. (Credit: David M Brown et al., Courtesy BMC Biology)
ScienceDaily (Jan. 2, 2008) Two new articles provide further evidence that we have hugely underestimated the number of species with which we share our planet. Today sophisticated genetic techniques mean that superficially identical animals previously classed as members of a single species, including the frogs and giraffes in these studies, could in fact come from several distinct 'cryptic' species.
In the Upper Amazon, Kathryn Elmer and Stephen Lougheed working at Queen's University, Kingston, Canada teamed up with José Dávila from Instituto de Investigación en Recursos Cinegéticos, Cuidad Real, Spain to investigate the terrestrial leaflitter frog (Eleutherodactylus ockendeni) at 13 locations across Ecuador.
Looking at the frogs' mitochondrial and nuclear DNA, the researchers found three distinct species, which look very much alike. These species have distinct geographic distributions, but these don't correspond to modern landscape barriers. Coupled with phylogenetic analyses, this suggests they diverged before the Ecuadorean Andes arose, in the Miocene period over 5.3 million years ago.
"Our research coupled with other studies suggests that species richness in the upper Amazon is drastically underestimated by current inventories based on morphospecies," say the authors.
And in Africa, an interdisciplinary team from the University of California, Los Angeles, Omaha's Henry Doorly Zoo, and the Mpala Research Centre in Kenya has found that there may be more to the giraffe than meets the eye, too.
Their analysis of nuclear and mitochondrial DNA shows at least six genealogically distinct lineages of giraffe in Africa, with little evidence of interbreeding between them. Further divisions within these groups mean that in total the researchers have spotted 11 genetically distinct populations.
"Such extreme genetic subdivision within a large vertebrate with high dispersal capabilities is unprecedented and exceeds that of any other large African mammal," says graduate student David Brown, first author of the study. The researchers estimate that the giraffe populations they surveyed have been genetically distinct for between 0.13 and 1.62 million years. The findings have serious implications for giraffe conservation because some among these subgroups have as few as 100 members, making them highly endangered -- if not yet officially recognised -- species.
Journal articles:
Cryptic diversity and deep divergence in an upper Amazonian frog, Eleutherodactylus ockendeni. Kathryn R Elmer, Jose A Davila and Stephen C Lougheed. BMC Evolutionary Biology (in press)
Extensive Population Genetic Structure in the Giraffe. David M Brown, Rick A Brenneman, Klaus-Peter Koepfli, John P Pollinger, Borja Mila, Nicholas J Georgiadis, Edward E Louis Jr, Gregory F Grether, David K Jacobs and Robert K Wayne. BMC Biology (in press) http://www.biomedcentral.com/bmcevolbiol/
Adapted from materials provided by BioMed Central.
Bird Flu is an example of a new species forming right in front of our microscopes. When the species appears that is transmitted from human to human and kills everybody, that is an evolved species. Those who do not believe in evolution will not be affected of course.
All you need for a species is to look different somehow and breed true.
The struggle between species “lumpers” and “splitters” goes on (and on, and on. . .).
LOL
susie
So then, each breed of dog is a separate species?
susie
Each dog is a different species of the one dog.
I suppose you really believe that? Or, are you joking?
susie
It’s not a matter of belief but of balancing on the fine line between skepticism and enthusiasm.
Hmmmm.... did you think that up yourself?
susie
No, actually I found it in an old, dusty and forgotten book.
Sure thing. Bird Flu got ‘em all.
I wonder if Noah understood all of this.
These researchers will now embark on a save the froggy giraffe crusade and go after grant money whereas a farmer would crossbreed them and sell the frog legs as delicacies.
I have one black and white dog, one yellow dog and a chocolate colored one; they have to share a single habitat, I’m worried they will have all died off within a decade if I don’t do something soon.
Which brings you back to competition, right?
Each dog is a different species of the one dog.
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Allow me to correct this statement.
Each dogBREED is a different RACE of the one SPECIES.
You have genus and species. The rest are more or less nonfunctional classifications that keep biologists and Richard Dawkins employed and FR amused.
Since you “teach this stuff” I would hope that you are aware that that definition is full of holes and grey areas. Some species can produce fertile female offspring but sterile male offspring.
Are you saying there is a situation where a species has no fertile males?
There are many (esp. insects) with infrequent fertile males. I would not be surprised if there were instances where the fertile males had not yet been observed, but I can’t think offhand of a diploid species definitively shown to have none, ever.
From where?
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