Listen to our friend, colleague and occasional contributor Andy Jarvis talk about his quest to document the predicted effect of climate change on the world’s top 50 crops. Via.
Goats gnaw on geographic given
We’re used to thinking — or at least assuming — in agrobiodiversity conservation that genetic distance is a monotonically increasing function of geographic distance. It is, after all, a reflection of the great Waldo Tobler’s First Law of Geography: “Everything is related to everything else, but near things are more related than distant things.” And yet. Why should that necessarily be so for crops and livestock, so willfully and incessantly moved to and fro by people in all kinds of unpredictable ways?
A paper just out in Molecular Ecology in effect tests the First Law of Geography with goat genetic diversity data, microsatellites in fact. ((BERTHOULY, C., DO NGOC, D., THÉVENON, S., BOUCHEL, D., NHU VAN, T., DANES, C., GROSBOIS, V., HOANG THANH, H., VU CHI, C., & MAILLARD, J. (2009). How does farmer connectivity influence livestock genetic structure? A case-study in a Vietnamese goat population Molecular Ecology DOI: 10.1111/j.1365-294X.2009.04342.x)). Goat populations were sampled in 3-8 villages in each of 2-5 communes in each of 10 districts in the remote, mountainous, ethnically mixed Vietnamese province of Hang Giang, for a total of 492 animals. The genetic relationships among the animals were then analyzed.
To the surprise of the authors, the spatial structure of the overall population was poorly explained by simple geographic distance. The ethnicity of their keepers and the husbandry practices to which they were subjected did a much better job of predicting the genetic distance between goats. The most dissimilar goats were not necessarily the ones which lived furthest apart, but rather the ones which were kept in different ways by people of different ethnic groups.
So, if you wanted to maximise the diversity in a Vietnamese goat conservation programme, or your chances of hybrid vigour, you’d pick animals from different ethnic groups or production systems, and not necessarily from different ends of the country. Which is something that I remember sort of almost subconsciously doing when I was collecting crops, but it is nice to see it validated like this. I can’t remember offhand similar work on crops, but no doubt Jacob will set me straight soon enough. In the meantime, I revel in a rule proven.
Reporting threats to agrobiodiversity: A modest proposal
Yesterday Hannes, à propos of something else, reminded me of a post I did a few months back about ProMED which asked the question “Why do we still not have an early warning system for genetic erosion?” Today I read about pestMapper — “[an] internet-based software tool for reporting and mapping biological invasions and other geographical and temporal events.” Whose objectives is basically to make a more participatory, Web 2.0-like ProMED. Coincidence? Maybe. Anyway, this is exactly the kind of thing we’ve been thinking here a “global genetic erosion threat reporting and monitoring portal” might look like. Any thoughts? An idea worth pursuing?
Nibbles: Chicory symbolism, Watermelon disease, Olive documentation, Camassia quamash, Pig maps
- Chicory averts evil. Gotta get me some.
- Genebank watermelon material reveals sources of resistance to WVD caused by SqVYV. What?
- Israelis, Palestinians and Germans collaborate on DNA fingerprinting and quality evaluation of olive trees. Wait, what? Scroll down.
- Genetic structure of Native American food plant not really affected by Native Americans. This is the bulb that kept Lewis & Clark alive, apparently.
- Tracing Paper compares hog distribution in 1922 and now, finds little difference.
Nibbles: Pluots, Village chickens, Axolotl, Artisanal fishing, Fruit and climate change, Stamps, Hornless cattle, Artemisin for malaria, Aquatic agroecosystems characterization, Speciation and ploidy
- What’s the difference between pluots and plumcots? By the guy who wrote the book.
- ACIAR publication on village chickens, and another. Thanks, DAD-Net.
- Modeling the axolotl, the edible Mexican salamander, before it’s too late.
- Artisanal fishing data. Via.
- USDA looking to expand its fruit collection to cope with climate change. NOt the only ones, I imagine.
- Danes stamp on allotments. No, wait. Allotments on Danish stamps.
- Aussies find genetic marker for hornless cattle that will jump on barbie by themselves.
- Breeding better Artemisia annua.
- The diversity of farmer-managed aquatic systems in SE Asia.
- 15% of angiosperm speciation events are accompanied by ploidy increase. Much more in domesticated species, I bet.