- Species vulnerability to climate change: impacts on spatial conservation priorities and species representation. Yes, you can focus on sensitive species, but it comes at the cost of representativeness.
- Estimating management costs of protected areas: A novel approach from the Eastern Arc Mountains, Tanzania. Those are $ costs per pixel on the map, which I’ve never seen before. Don’t think they took into account the effects of climate change, though. Maybe they should get in touch with the Aussies above?
- The use of mycorrhizal inoculation in the domestication of Ziziphus mauritiana and Tamarindus indica in Mali (West Africa). It would help.
- A new integrative indicator to assess crop genetic diversity. Includes varietal richness, spatial evenness, between-variety genetic diversity, and within-variety genetic diversity. Not much left, really. Anyway, remember this from last week? Anyone out there going to put 2 and 2 together?
- Assessing Nutritional Diversity of Cropping Systems in African Villages. A new tool! Different from the integrative indicator above! Anyone going to put 4 and 2 together?
- Agriculture-Nutrition Pathways Recognising the Obstacles. “The pathways between agriculture and nutrition seem to be laden with impediments, particularly in the form of intricate household preferences.” Those pesky preferences.
- The chestnut blight fungus world tour: successive introduction events from diverse origins in an invasive plant fungal pathogen. Asia to N. America to Europe, but more than once. All very complicated. The surprising thing is that low diversity and low admixture have nevertheless still resulted in success in disparate places. What fiendish molecular or biochemical mechanism is behind this? Only more research will show, natch.
- Translocation of wild populations: conservation implications for the genetic diversity of the black-lipped pearl oyster Pinctada margaritifera. Introducing some wild individuals near farms leads to more diverse farmed populations, right? Nope. The farmed populations are way diverse already and if anything the diversity is moving the other way.
- Maize x Teosinte Hybrid Cobs Do Not Prevent Crop Gene Introgression. That’s because the hybrid cobs break apart much more easily than maize.
- Detecting population structure and recent demographic history in endangered livestock breeds: the case of the Italian autochthonous donkeys. Microsatellites confirm existence of 8 breeds of Italian donkey, though there is also significant substructuring within each by farm. This apparently calls for a “synergic management strategy at the farm level,” which basically means using the breed as the unit of conservation but being careful about inbreeding.
- Evolutionary tools for phytosanitary risk analysis: phylogenetic signal as a predictor of host range of plant pests and pathogens. Work out host susceptibility by looking at existing pest preferences and phylogenetic distance from the stuff the pest is known to like.
Nibbles: AVRDC, PPB, Local foods, Emergency food, AnGR meeting, Tilapia, Agave, Asses, New cassava, Diversity for services, Climate change and phenology
- 40 years of AVRDC celebrated. Lots more stuff on vegetables below, so stick around if that grabbed you.
- Breeding with farmers, an ICARDA manual. Are there any examples with vegetables, I wonder?
- Let’s Go Local! See the ABC piece before it disappears from the front page. But it’s not just karat bananas that you need, of course.
- Going local in Philippines too. And India for that matter. And, ahem, Arkansas. Oh and Amazonia.
- Another use for baobab. I feel a factsheet coming on.
- And here are some utterly different fruits.
- Talking AnGR in Latin America.
- GIFT tilapia in India! Look it up, we did a Brainfood on it.
- A Belgian milestone. Put out more flags.
- Is it Cinco de Mayo yet? Well, break out the tequila anyway.
- Is it World Donkey Day yet?
- “Farmer associations hope TME 419 will soon spread across the whole country.” That would be a fancy new cassava in DRC. Anybody worried about that at all?
- Plant diversity key to zzzzzzzzzz…
- Well this will wake you up.
Nibbles: Fungi, Pastoralism, Climate hoofprints, Ancient farmers, Pineberry, Yellow Rust, Rio+20
- Mushrooms in Art: why, and what good has it been.
- Keep moving that livestock; it’s more profitable.
- And … noted promiscuous communication expert confuses cow and elephant in search of livestock’s climate hoofprint.
- Best blog account of those Swedish farmers from Cyprus.
- Back to the strawberry’s future: meet the pineberry.
- Too late for Robigalia, yellow rust threatens triticale.
- Lecture of Dr Maurits van den Berg – “The future of land”. You’ll get nothing from the link, but the presentation made me wish I’d been there.
Brainfood: Lupin restoration, Balkan wheat drought tolerance, Metabarcoding, Wild sheep genetics, Organic vegetables, Diversity protects, Sorghum geneflow, Wild sunflower genetics
- A Molecular and Fitness Evaluation of Commercially Available versus Locally Collected Blue Lupine Lupinus perennis L. Seeds for Use in Ecosystem Restoration Efforts. Commercial seed sources can be dodgy, and that’s a problem.
- Comparison of responses to drought stress of 100 wheat accessions and landraces to identify opportunities for improving wheat drought resistance. 20 Balkan landraces seemed to be more drought tolerant than 80 accessions sourced globally.
- Towards next-generation biodiversity assessment using DNA metabarcoding. You gotta be kidding me, metabarcoding? Will they be applying it to soils? Yep.
- Selection and microevolution of coat pattern are cryptic in a wild population of sheep. You need to look at the genes.
- Will they buy it? The potential for marketing organic vegetables in the food vending sector to strengthen vegetable safety: A choice experiment study in three West African cities. Not enough.
- Plant diversity improves protection against soil-borne pathogens by fostering antagonistic bacterial communities. Chalk another one up to diversity. Did they say soil?
- Local scale patterns of gene flow and genetic diversity in a crop–wild–weedy complex of sorghum (Sorghum bicolor (L.) Moench) under traditional agricultural field conditions in Kenya. Mostly crop-to-wild, which could be a problem if transgenics are ever grown. If.
- Adaptation with gene flow across the landscape in a dune sunflower… is leading to “ecological” speciation.
Pitfalls in modeling the effects of climate change on genetic diversity
Don’t you just hate it when a striking message from an elegant model is complicated by, well, facts? I may have Nibbled a press release on a recent modeling study from Wageningen University. The crux of the results was that as species migrate north due to climate change, they shed diversity from the central, most diverse part of their distribution, which is bad for their ability to adapt.
Plant and animal species can lose their ability to adapt as a result of climate change. This is shown by research performed by Marleen Cobben with which she hopes to obtain her doctorate at Wageningen University (part of Wageningen UR) on 17 April 2012. Cobben used computer calculations to illustrate how the genetic base of plants and animals is seriously deteriorating due to climate change. The smaller genetic base makes species more vulnerable to problems such as diseases. Moreover, the fragmentation of landscapes and the loss of wildlife areas is accelerating this decline.
This was interesting to me because we routinely, and perhaps somewhat blindingly, these days say that climate change will lead to shifts in the distributions of species. Crop wild relatives, say. Shift that will absolutely require germplasm collecting and ex situ conservation. Nothing else will do. Forget about in situ, ex situ it must be. That’s because, when added up, these shifts in the distributions of individual species will result in profound alterations in the geographic patterns of species diversity. Some hotspots will disappear, some diversity-poor areas will be enriched. Difficult to plan in situ conservation under these conditions. Ergo, need to collect. Also, the distributional shifts required for a species to track the climate will in most cases surely be faster than the rate of migration of the species, leading inexorably to its extinction. Need to collect, and quick. I mean, what can a poor species do under climate change besides move or perish? Need to collect, I tell you.
Well, adapt, of course, that’s what it can do. And collecting is not going to help with that. Need to do in situ, maybe assisted migration, you clod.
So a study which suggests that climate change is likely to also result in a decrease in genetic diversity within species would seem to push the pendulum further towards ex situ. Without being able to delve into the particularities of the model, the results seemed plausible to me, assuming that the highest diversity was indeed found in the central part of the distribution. Genetic erosion ensues. Won’t be able to adapt. Need to collect!
I can’t remember if I did nibble it, but I certainly sent the link to the Crop Wild Relatives mailing list. And it elicited an interesting, skeptical reply from Prof. Jonathan Gressel of the Weizmann Institute of Science in Israel. The professor pointed to a possible mechanism by which climate change could conceivably increase genetic diversity.
Unfortunately it is common for modelers to to say that their research “shows” (in this case), demonstrates or even proves something. As a sometime modeler (first model on herbicide resistance published in the Journal of Theoretical Biology in 1978), the best models can do is suggest priorities for experimentation to validate them. Ignoring (or not knowing) one important parameter can skew the model. My mathematician colleague always kept mumbling at me: “Garbage in, Garbage Out”. I would hazard a guess that one parameter was left out of the simulations: the fact that sub-lethal stresses increase mutation rates. Thus, climate change stress will increase mutational diversity in pre-existing genes. For a discussion of this, see: Pest Management Science 67:253-257, 2011.
Oh no, you mean we have to do both ex situ and in situ? Well that won’t do at all. While I naturally hope Marleen Cobb successfully defended her PhD last week, I hope that when she comes round she’ll tweak her model and help us decide once and for all.