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Is the kouprey a species?

The kouprey is a very elusive wild bovid that is said to roam the Southeast Asian jungle. It was only discovered by outsiders at the beginning of the last century, but it has seldom been seen since and there are concerns that it may, in fact, already be extinct. (It is currently listed on the IUCN Red List of Endangered Species). As if that wasn’t bad enough, there is now a vigorous debate about whether the kouprey is — or was — in fact, a separate species at all, or merely some type of feral hybrid.

A report published some months ago in the Journal of Zoology showed that a comparison of mitochondrial DNA obtained from several banteng revealed some homology — similarity — with a previously published DNA sequence from a kouprey. ((Galbreath et al., 2006. J. Zool. 270:561)) The banteng is another bovid that has to some degree been domesticated, but can also still be found in the wild in several Southeast Asian countries.  Based on their analysis, the authors concluded that the kouprey is more than likely just a hybrid originating from crosses between zebu cattle and the banteng. Now, some might argue that it is pretty bold to reach such a profound conclusion based on a very small sample size, and not surprisingly some have indeed so argued. They have pointed out that anatomical and even DNA evidence from their own studies did not support stripping the kouprey of its species status. ((Grigson, 2007. J Zool. 271:239; Hassanin and Robiquet, 2007. J. Zool. 271:246)) An alternative explanation might simply be that there has been introgression of DNA from one species into the other by occasional matings. And there is ample evidence that this has happened in other species. Cattle DNA is commonly found in the American bison, for example, because of past attempts by cattle breeders to generate what they thought would be more viable bison-cattle hybrids. ((Rasmussen et al., 2005. Mol. Reprod. Dev. 70:228))

What is clearly needed to settle the matter is additional analysis of nuclear DNA obtained from more than one kouprey. But if the animal has, indeed, already disappeared, that may prove to be difficult. ((Contributed by Michael Kubisch))

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Swiss clock up ecosystem services

A paper in the latest Journal of Applied Ecology demonstrates that biodiversity provides valuable ecosystem services — though, pace the previous post, it deals with just one of these services. Swiss researchers looked at the effect of “ecological compensation areas” (ECA), meadows managed in such a way as to maintain high levels of biodiversity, on nearby fields which were managed more intensively. In particular, they focused on the effect on pollinators. They concluded that pollinators will be more diverse and effective in intensively managed farmland — thus providing a better service — when there is a botanically diverse ECA close by.

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Biodiversity even more valuable

A study published in tomorrow’s Nature (news item) suggests that previous estimates of the value of biodiversity in supplying ecosystem services may have consistently underestimated its importance. This is because previous efforts looked at single services, such as clean water or pollination. Professor Andy Hector from the University of Zurich, Switzerland and Dr Robert Bagchi from the University of Oxford developed a new method to look at multiple ecosystem processes in the same analysis. According to Professor Hector “previous analyses have been too narrowly focused … and have effectively assumed that the species that are important for one ecosystem service can provide all the other services too – but that doesn’t seem to be the case”.

Applying their method to data from European grasslands, Hector and Bagchi found that higher levels of biodiversity were required when all seven of the measured ecosystem services were taken into account than when focusing on any single ecosystem service in isolation. Moreover, different ecosystem services were affected by different groups of species. Dr Bagchi explained that “because different species influence different ecosystem services more species are required for a fully-functioning ecosystem than for one managed with a single goal in mind”.

What’s really neat is that the researchers are now testing their ideas in the tropics. Professor Hector is one of the lead researchers on the Sabah Biodiversity Experiment in Malaysian Borneo, which investigates whether tree-replanting schemes are more successful in restoring fully-functioning forest ecosystems when they use a high diversity of species than the monocultures that are usually planted. That’ll be one to watch.

doi:10.1038/nature05947

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ni-Vanuatu get traditional

I don’t know how I missed it. Having just finished a longish stint in the South Pacific, I still try to keep up with what’s going on down there, but the fact that 2007 is the “Year of the Traditional Economy” in Vanuatu totally slipped through my net. ni-Vanuatu are wonderful, friendly people and this sounds like it’s going to be fun. I’m sorry I’m not there (or nearby at any rate) any more, I would probably have tried to link up with some of the planned activities, as agricultural biodiversity seems to be very much on the agenda. Here’s one of the things that people are being encouraged to do, for example:

Each family and community to feed more pigs and chickens, plant more and/or larger gardens, plant more yams and taro, plant more fruit and nut bearing trees, plant more trees for making canoes and tamtams, plant more pandanas trees and plant more of other traditional foods and resources not listed here.

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Selecting forages

You may remember a longish post sometime back describing a piece of software called LUCID which can be used to prepare multi-access keys for the identification of species or varieties. Well, I’ve recently come across a slightly different use to which LUCID can be put. Normally you would enter into the software what each species looks like — the length of their petioles, colour of their flowers, shape of their pistils. What if, instead, you put in how each species performs under different conditions — of altitude, precipitation, soil pH, salinity, management etc.? What you would end up with is a tool for selecting which species would do well under specified combinations of conditions, or for specific purposes. And that’s exactly what a consortium of organizations interested in forages for the tropics has done. There are also factsheets on each of several dozen tropical forage grasses and legumes, including photographs and maps of suitable geographic areas.