Showing posts with label Donald Miles. Show all posts
Showing posts with label Donald Miles. Show all posts

Saturday, April 16, 2011

From Athens with love: greetings from "His Dudeness"






I have now spent about a week at Ohio University in Athens, and as you see on the pictures I have been working hard with Shawn. Apart from discussing geometric morphometrics, predator-mediated natural selection and dragonfly wings, I have had the opportunity to participate in several discussion groups, ranging from niche conservatism in salamanders to the strength of selection in natural populations. It has been fun and entertaining.

Athens is a lovely little liberal "latte-town" in Ohio, with about 30 000 inhabitants, of which about 70 % are students and academic staff at OU. There are an impressive high number of bars and coffee shops around, and one of the most popular is the Casa Nueva, which is on the uppermost picture. There we have had many margharithas and beers and listened to some good live music. 

By the way, OU scientists are impressive in their party mood and habits, we have been going out every evening, and I think I will need a loooong recovery when I am back in Sweden. I feel I have been very welcomed and well-treated during my visit, and the two research seminars I gave were very appreciated by students and faculty. I especially enjoyed discussing science with Molly Morris, who works on sexual selection in swordtails, and ecomorphologist Donald Miles, apart from Shawn, of course.

Close to Casa Nueva, on the corner in the picture above, there is an excellent T-shirt shop, where I bought the lovely T-shirt I am wearing, showing one of my favourite actors (Jeff Bridges, "The Dude") from one of may favourite movies The Big Lebowski. I use this T-shirt the first time before we go to a party (again!) tonight at Donald Miles' house. What could be a better combination than also trying out some of their excellent local beers from Ohio's microbreweries, and posing in front of the photographer (Shawn) at his motorcycle and Volkswagen bus?

Friday, May 14, 2010

Goodbye to 20 % of all lizards by 2080?

























An interesting, but depressing study was published in Science this Friday
. A research team lead by Barry Sinervo, and also including my colleagues Donald Miles (University of Ohio) and Jean Clobert (CNRS, France) have shown an alarming high rate of local population extinctions in Mexico over the last 35 years. Based on these observed real-time extinctions and biophysical modelling of lizard body temperatures in the field (based on experiments), they conclude that the rate of climate change and increasing temperatures are too high for the lizards to have time to adapt.

Lizards and other ectotherms are constrained in their foraging time in hot climates because they must avoid overheating. In particular, viviparous lizards suffer, since pregnant females are especially sensitive: they carry embryos in their bodies which easily die at high temperatures. It is therefore not surprising that most viviparous lizard populations are found at higher latitudes and altitudes, i. e. in colder climates. As temperatures increase dramatically in these environments, these viviparous lizards face a significantly higher extinction risk compared to oviparous lizards, largely because their foraging time becomes drastically reduced and they have to spend a larger part of the day in the shade, to avoid overheating.

The research team estimate, conservatively, that about 20 % of all lizard species on Earth run a significant and serious risk of becoming extinct before 2080, unless the current global warming trend is reversed. This is rather alarming, as lizards is only one of several organismal groups that are likely to have passed the "extinction" threshold determined by anthroprogenic global warming. Other groups that have been discussed are amphibians.

Perhaps we are now entering the next (the sixth) massextinction, which will also drag humans away from this planet? Keep in mind that one of the most famous massextinctions about 251 milllion years ago (The Perman-Triassic massextinction event) killed between 70 and 96 % of all living species, and happened after a global temperature increase of about 6 degrees. Incidentally, a six-degree temperature increase is one of the scenarios outlined by UN:s intergovernmental panel IPCC in their most pessimistic scenario over the coming 100 years (although some climate scientists consider this a rather realistic scenario). If so, Homo sapiens might not have long time left on this planet.

You can read more about this lizard study here, and do not forget to watch the video, where Jean Clobert and Barry Sinervo discuss their findings.