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First study of global pollinator value

Back in October 2006 the Royal Society published an online version of a comprehensive study that was the first attempt to put a global value on pollinators. It attracted some attention back then, at The Worsted Witch, who got it from Science Daily. We missed it at the time ((Probably because the whole site was pretty new)), but as the paper version has just been published, that’s enough reason to revisit it ((Thanks to Michael Kubisch for sending the information below and the link)).

Very briefly, the article shows that 87 of the leading 115 crops depend to varying degrees on animal pollination. These 87 crops represent 35% of the world’s food production. While a few food plants are pollinated by birds or bats, the most important pollinators are, of course, honeybees, domesticated and wild. This is particularly troublesome in light of the various threats to the domesticated bee. The authors conclude that agricultural intensification jeopardizes wild bee populations and plead for more research into landscape management practices that would enhance wild bee viability.

Interestingly, I couldn’t find an actual cash value for pollination services in the article, but maybe I didn’t look hard enough.

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Magnolias in trouble

The Global Trees Campaign says that 131 of 245 wild Magnoliaceae are threatened worldwide. According to this press release from BGCI:

The significance of this potentially catastrophic loss lies not only in the threat to the genetic diversity of the family, but also because they are a highly sensitive indicator of the well-being of the forests in which they are found. Magnolias are among the most ancient groups of flowering plants and have long been cultivated by mankind.

You can download a PDF of the new Magnoliaceae Red List. The publication of the red list has been widely covered by the press, including New Scientist. Many species have medicinal uses and some are used for food.

Predictably, protected areas are highlighted as an important approach to the conservation of these species, particularly in their hotspot in southern China. A separate new study

concludes that protected areas are necessary for preventing the loss of species due to climate change – provided that shifts in species’ ranges are factored into early analysis of whether to expand current protected areas or create new ones.

The new red list includes distribution maps of all magnolias, clearly an important first step.

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Multiple founder effect

The common wisdom is that crops are most diverse in their centres (or secondary centres) of domestication, because that’s where people have been playing with them longest. Wild species, too, are often less diverse when they have moved to a new area. That’s down to the founder effect; a small bunch of founding individuals will have a less diversity than the population as a whole and is also more subject to random fluctuations that can change things from the original population. But on the Invasive Species Blog (via this month’s Mendel’s Garden) I recently read that reed canary grass (Phalaris arundinacea) is much more diverse in North America, where it is a recent arrival, than in Europe, its home. Genes from all over the old world are mixed up within single individuals in North America, whereas they are never found together in Europe. The reason, apparently, is that the species has been introduced many times, presumably from many places, and this has brought widely separated populations together and given the opportunity to mingle their genomes.

I wonder whether the same is true for some of the crops that have really travelled around, like tomatoes or peppers.

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Transitions

Well, my three months’ break in Kenya is coming to an end, unfortunately. I’ll be starting a new job in a couple of days, and, what with the moving and getting settled in and stuff, blogging will probably be a bit slow over the next week or so. But Jeremy will take up the slack, wont you Jeremy?