- Sorghum going to need a hand in India. Rice in China? Maybe not so much.
- Photos of the 6th Annual Hawaii Seed Exchange.
- More Pacific stuff: 3000-year-old Lapita chickens were haplogroup E, “a geographically widespread major haplogroup consisting of European, Middle Eastern, Indian, and Chinese domestic chickens.”
- More on that thing about the gut biota being adapted to ethnic diets.
- Wolves may have been turned into dogs earlier than previously thought.
- Organic farming good for underground mutualists. Which sounds totally appropriate somehow.
- Crop wild relatives: all you ever needed to know.
- Bring back bees by bringing back the boy scout bee-keeping badge.
- Here’s a weird one. US to cut 1.5 trillion calories from food by 2015. And there are 1 billion hungry. You do the math.
- Farmers rear endemic moths on intercropped host plants for high quality silk in Madagascar. Enough hot buttons in there for ya?
Spatially explicit conservation
The May 2010 Diversity and Distributions is a special issue on “Conservation biogeography — foundations, concepts and challenges.” I haven’t had a chance to go through it all, but there are very interesting-looking contributions on how to improve niche model, the role of citizen science and the biogeography of climate change. More when I actually read a couple of the papers.
Crop genebanks in the Global Biodiversity Outlook
Seed banks play an important role in conserving the diversity of plant species and crop varieties for future generations. Among the most ambitious programmes for ex situ conservation are the Millennium Seed Bank Partnership, initiated by the Royal Botanic Gardens Kew and its partners worldwide, which now includes nearly 2 billion seeds from 30,000 wild plant species, mainly from drylands; and the complementary Svalbard Global Seed Vault, which has been constructed in Norway, close to the Arctic Circle, to provide the ultimate safety net against accidental loss of agricultural diversity in traditional gene banks. The vault has capacity to conserve 4.5 million crop seed samples.
That’s from the section on genetic diversity from the CBD/UNEP Global Biodiversity Outlook 3, just out (pp 51-53 of a large pdf). And very welcome it is too.
Some of it is not particularly well done, but one is surprised to see it done at all. It would have been nice to have had more examples of genetic erosion than this estimate for rice in China, for example:
…the number of local rice varieties being cultivated has declined from 46,000 in the 1950s to slightly more than 1,000 in 2006.
And what does this mean exactly? Who cultivates wild relatives of rice?
In some 60 to 70 per cent of the areas where wild relatives of rice used to grow, it is either no longer found or the area devoted to its cultivation has been greatly reduced.
Probably something has been lost in translation. On the positive side of the conservation ledger, there is the assertion that:
For some 200 to 300 crops, it is estimated that over 70% of genetic diversity is already conserved in gene banks, meeting the target set under the Global Strategy for Plant Conservation.
This figure is much quoted, but I’ve never fully understood how it was arrived at.
Anyway, as I say, at least crop diversity and its ex situ conservation is in there. And the International Treaty on Plant Genetic Resources for Food and Agriculture gets a mention. We should be grateful for that.
Gulf oil spill not much of a threat to one crop wild relative
The Gulf oil spill is threatening some Globally Important Bird Areas, according to the LA Times:
And other protected areas too. Unfortunately, we don’t have a similar map for crop wild relatives, at least not just yet, at least not so easily available. So it’s hard to estimate the overall threat posed by the oil spill on these genetic resources — which are arguably of greater importance than most birds, but there you go. What we can do — just about — is look at the distribution of individual species. And that is what our friend Julian at CIAT has done for a wild bean, Phaseolus polystachyus.
Not in any particular danger, though one or two coastal populations may be affected, I suppose. But I just wonder if one day the LA Times will publish a map showing the Globally Important Crop Wild Relative Areas threatened by some calamity or other.
Getting to grips with ecological interactions
Something just in from our occasional contributor Jacob van Etten.
Climate change will shift the limits of the suitable areas of many wild animals and plants, including crop wild relatives. Some species may adapt by gradually moving into areas which resemble their current home area. In other cases, no bridges exist to connect old and new suitable areas and a helping hand may be needed. Translocating species, or “assisted migration” has complex risks and ethical implications. Another approach would be to intensify ex situ collection efforts aimed at those species vulnerable to climate change. “Niche modeling”, which matches species to specific climatic conditions is helpful to locate problem areas.
All of this assumes that currently animals and plants are mainly held in place by climatic factors. ((There are other issues with niche models as well and more sophisticated approaches are being developed.)) But what if this is not the case? Imagine the aftermath of a glaciation. The ice retreats and species start to move towards the poles to occupy new territory. Two competing species, A and B, start to expand their range, but A is a better disperser than A. Since species A arrives first in most places, competing species B is absent, but not because the area is not suited climatically for species B. This would seriously confuse a niche model and its ability to predict future distributions after climate change.
Gilman and co-authors review the evidence on how interactions between different species influences the impact of climate change on species in a recent paper. ((Gilman, S., Urban, M., Tewksbury, J., Gilchrist, G., & Holt, R. (2010). A framework for community interactions under climate change Trends in Ecology & Evolution DOI: 10.1016/j.tree.2010.03.002)) Experiments with fruit flies, literature reviews and modeling studies all show that biotic interactions are crucial in predicting the effects of climate change. However, most models to predict the effects of climate change on species survival ignore these interspecific interactions. The complexity of webs of ecological interactions makes it difficult to draw general conclusions.
Gilman et al. suggest a divide-and-conquer approach to solve the puzzle. They propose to split communities in small modules of 2-4 interacting species, each characterized by a different network of interaction (mutualism, predation, competition, etc.). Through coupled modeling and empirical studies focused on such modules, Gilman et al. hope that some general trends will emerge. Lots of work needs to be done, however, before ecologists will be able to distinguish those trends. Gilman et al. also note that putting the modules together in communities may not be straightforward.
Obviously, this approach requires massive data collection and experimentation, premised on the idea that in the end some pattern will emerge from the data and that it will be possible to predict community level phenomena from the constituent elements. In spite of the importance of all this work to gain insight in the workings of ecological communities, there is no guarantee that we will end up being able to predict species extinction before it happens. In my view, ecological interactions are just too complex to draw any hard conclusions from bottom-up studies. For instance, pollinator networks can change from year to year. And only part of this information on ecological interactions is relevant to predict species survival/extinction. The approach proposed by Gilman et al. seems to steer towards a mismatch between ecological work and the hard questions of management, conservation and policy making.
How can the ecological interactions relevant under climate change be understood without losing ourselves in the details while working with available data? The decreasing costs of DNA analysis and the push for citizen science for conservation will hopefully make more data on gene flow and species occurrence available for monitoring purposes. Would it be possible to infer interactions from these data?
In molecular biology inferring complex interactions from massive data is very common. Vera-Licona and Laubenbacher (2008) apply mathematical methods originally developed for the inference of biochemical networks to ecological interactions. The method makes it possible to pinpoint the sources of remaining uncertainty. It seems that the method is being picked up by others. My feeling is that work along these lines will become important to bring ecology closer to management practice.