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Aug

1

2008
 
 

What do krill kill?



Using molecular techniques to understand krill diet put another krill on the barbieComplex food webs could become easier to analyze with the advent of molecular techniques to identify the remains of prey items from part-digested stomach contents. However, a major stumbling block has been spotting the DNA of rare prey items against a background overwhelmed by the predator's own DNA. Writing in Frontiers in Zoology, Hege Vestheim and Simon Jarman – biologists at the University of Oslo and the Australian Antarctic Division, respectively – describe a new method to block predator DNA from the identification process. As a result, their tests on Antarctic krill Euphausia superba were able to identify, for the first time, what one of the most abundant animals in the world eats to survive the winter. The method must assume krill don't resort to cannibalism to make it through the toughest half of the year, but otherwise presents a neat way to find out what an animal has eaten: the study even, er, threw up several unknown species of algae. Source: Vestheim H & Jarman SN (2008) Blocking primers to enhance PCR amplification of rare sequences in mixed samples – a case study on prey DNA in Antarctic krill stomachs. Frontiers in Zoology DOI: 10.1186/1742-9994-5-12 Image: © NOAA

Filed Under Endangered species, Marine, Monitoring, Restoration, Tools and technology | Leave a Comment

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Jun

6

2007
 
 

Mists slowly clearing over clouded leopards



Species revisions continue, with major conservation implications clouded leopardClouded leopards continue to be a target for taxonomic splitters, as a study published recently in Frontiers in Zoology demonstrates. Andreas Wilting, at the University of Würzburg, and colleagues built on the findings of earlier studies to confirm the proposed new status of cloudies on Borneo, recently upgraded from subspecies to species (Neofelis diardi). But they went further than that: having reiterated that mainland leopards Neofelis nebulosa were distinct from those found on Borneo and Sumatra, they discovered that the latter two islands host significantly different N. diardi subspecies. The upshot of this latest split is that the island populations should be treated as separate conservation units, whose long term management plans should be designed independently. Watch this space for yet more new clouded leopard taxa, each more rare and vulnerable than the last. Source: Wilting A, Buckley-Beason VA, Feldhaar H, Gadau J, O’Brien SJ & Linsenmair KE (2007) Clouded leopard phylogeny revisited: support for species recognition and population division between Borneo and Sumatra. Frontiers in Zoology DOI: 10.1186/1742-9994-4-15 Related story in Conservation magazine: Democratizing Taxonomy Image © Dieter Spears

Filed Under Endangered species, Habitat, Monitoring, Restoration | 1 Comment

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Mar

9

2007
 
 

Mind the gap



Blue, but which blue?Butterfly DNA barcoding study reinforces need for traditional taxonomy DNA barcoding doesn’t always work, according to a recent study published in Frontiers of Zoology. Martin Wiemers and Konrad Fiedler, both at the University of Vienna, found that the so-called “barcoding gap”, upon which the technique depends, doesn’t exist among some well-studied species of Lycaenid butterflies. The hi-tech method (think Spock’s “tricorder”) uses differences in a single short stretch of mitochondrial DNA to classify life, relying on the genetic sequences of individuals of the same species being more alike than those of individuals from different species. Unfortunately, Wiemers and Fiedler found that in their study’s butterflies at least, there was a substantial overlap in the within- and between-species differences. We still need those crusty old-fashioned taxonomists after all. Source: Wiemers M & Fiedler K (2007) Does the DNA barcoding gap exist? - a case study in blue butterflies (Lepidoptera: Lycaenidae). Frontiers in Zoology DOI:10.1186/1742-9994-4-8 Image © Nikolay Dimitrov Related article in Conservation magazine: Democratizing taxonomy

Filed Under Economics and conservation, Monitoring, Tools and technology | Leave a Comment

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