Smaller American Lawns Today. Edible Estates. Freedom Lawns. Recent thinking about the American suburban lawn sounds like a microcosm of the debate about diversity and sustainability in agriculture in general. Read all about it in The New Yorker.
A few seeds held in a muddy hand
A review of The Oxford Book of Modern Science Writing by Richard Dawkins included a beautifully poetic rumination on agrobiodiversity:
The great Ice Age herds were destined to vanish. When they did so, another hand, like the hand that grasped the stone by the river long ago, would pluck a handful of grass seed and hold it contemplatively. In that moment, the golden towers of man, his turning wheels, the vast learning of his packed libraries would glimmer dimly there in the ancestor of wheat, a few seeds held in a muddy hand. Without the gift of flowers and the infinite diversity of their fruits, man and bird, if they had continued to exist at all, would be today unrecognizable. Archaeopteryx, the lizard-bird, might still be snapping at beetles on a sequoia limb; man might still be a nocturnal insectivore gnawing a roach in the dark. The weight of a petal has changed the face of the world and made it ours.
You can get the full thing online. It’s from How Flowers Changed the World by Loren Eiseley.
The deep history of dogs and horses
And talking of horses. It’s kinda amazing to think that the dog and the horse, eventually domesticated at different times and in different places in Eurasia, can trace their lineages back to ancestors which co-evolved as hunter and prey on the grasslands of a continent — North America — which was at the time completely cut off from the rest of the world, and to which they were re-introduced, again quite independently, millions of years later.
Grey horses understood
An easy way to mark yourself as a novice is to call a white horse white. They’re greys. I don’t know why, but there it is. ((Probably specifically to enable horsey types to act superior.)) Today, thanks to a paper in Nature Genetics, I do know why they’re grey. ((Gerli Rosengren Pielberg, Anna Golovko, Elisabeth Sundström, Ino Curik, Johan Lennartsson, Monika H Seltenhammer, Thomas Druml, Matthew Binns, Carolyn Fitzsimmons, Gabriella Lindgren, Kaj Sandberg, Roswitha Baumung, Monika Vetterlein, Sara Strömberg, Manfred Grabherr, Claire Wade, Kerstin Lindblad-Toh, Fredrik Pontén, Carl-Henrik Heldin, Johann Sölkner, Leif Andersson (2008). A cis-acting regulatory mutation causes premature hair graying and susceptibility to melanoma in the horse Nature Genetics, (), – DOI: 10.1038/ng.185)) Turns out they are over-expressing two genes on horse chromosome 25, thanks to a duplicated bit of DNA 4600 base pairs long. And that’s true in more than 800 greys from 8 different breeds. the duplication has not been found in any non-grey horses.
Greys generally start off with dark hair, but gradually lose the dark pigment, leaving them with white hair and, usually, black-skin. Alas, greys also often develop melanomas that reduce their lifespan, and also show depigmentation of the skin like viteligo in humans. So what’s going on? Leif Andersson and his colleagues suggest that maybe the two genes, called STX17 and NR4A3, may be speeding up the rate of division of pigment cells in the skin and the hair follicles. In the skin, this leads to melanomas. In the hair follicles it depletes the stem cells.
The miombo woodlands on Google Earth
A video on capturing, sharing and interacting with spatial information on the miombo woodlands of Malawi. Via.