Friday, July 27, 2007

Long-term rainforest study in danger

Of all the ironic things...

It looks like one of the world's watershed ecological experiments is in danger of succumbing to the pressures it was designed to study. The Biological Dynamics of Forest Fragmentation Project (formerly the Minimum Critical Size of Ecosystems Project) is a large-scale field experiment on the effects of habitat fragmentation that has been in existence since the late 1970s. This study, initiated by Dr. Thomas Lovejoy, essentially took a swath of Amazon rainforest and created a patchwork of forest fragments of different sizes. The initial intent was to empirically solve the SLOSS question (Single Large or Several Small) - the question for conservation biologists of whether it is better (biodiversity-wise) to create one large reserve or many, smaller ones who's total area equaled the larger (the SLOSS argument, in turn, was influenced by another seminal work - MacArthur's and Wilson's Theory of Island Biogeography). As with any good scientific endeavor, this experiment has revealed a lot more than it originally set out to - e.g. the importance of edge effects, microhabitat changes, habitat diversity, and on and on...The work that has come out of this study has influenced countless conservation efforts and has been a cornerstone topic for teaching about environmental science, experimental design, conservation biology, and general ecology.

Unfortunately, it now seems that the experiment is in serious of danger of being destroyed by encroaching development. The population in the surrounding area has grown to the point where people are starting to spread out into the experimental area - burning some of the forest plots and raiding research camps. I suppose this sort of thing was inevitable with the rate of population growth, especially in developing countries, but it will be a sad day for science if/when such an important and innovative experiment is forced to shut down.

Wednesday, July 25, 2007

Astrophysics Rocks!

Sorry marine biologists, but it looks like you're not the only rock stars in the science community.

The field of astrophysics is about to usher in their very own MEGA rock star - Brian May, formerly of Queen. Apparently the 60-year old rocker has just about wrapped up his doctoral dissertation on "Radial Velocities in the Zodiacal Dust Cloud".

How many PhDs do you know of that are also world-wide musical icons? Really, who would of thought that "Fat Bottomed Girls" would be written by a physicist?

(Thanks for the link, Linda)

Thursday, July 05, 2007

Tangled Bank #83

The latest edition of the Tangled Bank is now up over at Aardvarchaeology.

Monday, July 02, 2007

African elephants live in Africa for a reason

In this month's Scientific American is an article about a topic that gets my blood going whenever I read about it - the concept of Pleistocene Rewilding. For those of you who haven't heard of it, Pleistocene Rewilding is the idea that we should introduce non-native megafauna to North American ecosystems. The basic idea is that up to 10,000 years or so ago, relatives of these animals roamed North America as key cogs in the natural landscape. Then humans arrived and most of the large animals went extinct. The correlation between the extinctions and the arrival of Homo sapiens has lead to the hypothesis that humans hunted the large herbivores to the point where their populations were too low to be sustained. With a lack of large herbivores, large carnivores were also unable to survive. The Pleistocene rewilding is an attempt to reverse this Pleistocene overkill.

Lions, mammoths, camels, horses, cheetahs, and others were all found in various ecosystems throughout North America and helped shape the evolution and ecology of plants and animals still found today. For example, it is hypothesized that the pronghorn's speed evolved to help it evade American cheetahs (why else should it run over 60 mph?), and that the large seeds of the honey locust tree were eaten and dispersed by mammoths (now, the honey locust has no natural seed dispersal). Proponents of Pleistocene rewilding see North American ecosystems as "broken", missing major players. Since the missing fauna are now extinct, the idea is to use extant species as proxies. Re-wilders want to import African elephants, cheetahs, lions, and camels to restore North America to what it was (might have been?) before humans killed off the large mammals.

I first read about Pleistocene rewilding some years ago in the now-defunct journal Wild Earth. More recently, researchers at Cornell have reinvigorated the rewilding push. I think it is a monumentally bad idea. First, it's gimmicky - the article in SciAm talks about the increased tourist revenues it would bring in and even shows an illustration with a monorail in the background. If this is what you want, go to Disney's Animal Kingdom, Six Flags' Wild Safari, or the San Diego Zoo's Wild Animal Park. Second, and most important, these animals don't belong here. I'm all for the conservation and restoration of ecosystems. The reintroduction of wolves to Yellowstone was a phenomenal, watershed event. But Canis lupus used to live there - in historic times nonetheless - and still were living relatively nearby. Before zoos, African elephants NEVER lived in North America. African cheetahs NEVER lived in North America. The Dromedary Camel NEVER lived in North America. And even though the American and African lions are considered subspecies of Panthera leo I wonder how similar they truly were (isolated for at least tens of thousnads of years, living in different environments). Haven't we seen the results time and time again of introducing non-native species to ecosystems?

I might think differently about Pleistocene rewilding if we were able to actually reintroduce the Pleisotcene fauna. How great would it be to see herds of mammoths roaming around? Or the chance to see a cheetah chase down a pronghorn? Alas, unless there's some Jurassic Park technologies out there, this ain't happening.