At the Ecological Society of America’s international meeting in Minneapolis last week, there were so many cool things to learn about, I felt like a kid in a candy store (as the EEB & Flow blog aptly put it). A few talks stood out as particularly exceptional, which I’ll summarize below. I’m sure I missed some equally fantastic talks; ESA Ecotone and EEB & Flow covered some that I did not attend. Without further ado, and in no particular order, these ecologists deserve a shout-out:
1) Justin Yeakel, a postdoc at Simon Fraser University, reported his research on extinction and food web dynamics over 6,000 years in Egypt by studying animals depicted on cave drawings and archaeological remains. He related animal presence/absence to human history and climactic change. He found that, “Persistence is predictable.” The sensitivity of animals to food web stability predicts their persistence. Virginia Gewin wrote a fantastic, more detailed summary of his research in an article in Nature News.
2) Erik Aschehoug, a postdoc and community ecologist at North Carolina State University, researches the rarest butterfly in the world, the St. Francis Satyr, native to a 5 hectare area along a river in eastern North Carolina. He recently discovered what the caterpillars of the species eat–a prairie wetland sedge called Carex mitchelliana–when his field assistant dropped his sunglasses in some weeds. This critically endangered butterfly spends most of its life as a caterpillar, so this sedge is essential to the population’s survival. Prairie wetlands are thought to be maintained by fire and flooding encouraged by beaver dams. As fire and beavers have declined in the area, so have the butterflies, researchers postulate. Aschehoug and his collaborators have discovered that cutting forest canopy along the river to open up wetland areas, which was thought to help restore the butterfly’s habitat, also increased predation rates on the butterfly, unless temporary dams were also built. Their results highlight the need for long-term monitoring to understand complex effects of restoration protocols. Funding is generally biased toward restoration action without this long-term monitoring and empirical approach.
3) Jacquelyn Gill, a postdoc at Brown University, questioned whether using the Pleistocene fossil record to calculate extinction rates will overestimate extinction rate, as had been previously suggested in the literature. According to her, this claim of overestimation is faulty because (1) it’s based on the last period of extinction, the last deglaciation of the Pleistocene, rather than looking over the whole time period; (2) it’s based on studies that focus on megafaunal extinctions; (3) the onset of the Pleistocene was changed from 1.8 million years ago to 2.5 million years ago, so researchers have missed some of what is now considered the Pleistocene when studying Pleistocene extinction; (4) different fields and different countries/continents call geological time periods and eras different names, which makes searching and integrating the literature very challenging; and (5) most researchers are limited by their taxonomic, temporal, or regional research framework. She asserts that considering the whole quaternary global record shows the true story, with 3 waves of extinction during the Pleistocene, the first associated with a cooling planet, the second with a change in the magnitude and duration of glacial and interglacials, and the third with human activity. From her extensive review of the literature, she found four mechanisms that pose the greatest extinction risk to a broad swath of organisms: (1) directional climate change combined with a geographical barrier to migration; (2) abrupt regime shifts (climate, acidification); (3) sea level rise; and (4) loss of ephemeral habitats.
4) Ty Tuff, a Ph.D. student at University of Colorado Boulder who is especially interested in integrating physics with ecology, is using 3D and 4D models of Earth to show that spatiotemporal patterns of migration across many taxa can be explained by solar current clines; ecologists have generally missed this pattern because of their terrestrial frame of reference. But solar current is influenced by Earth’s magnetosphere, atmosphere, and shape, all of which affect organisms’ activities in time and space. His take-home points were: (1) Observational frame of reference is relative to the observer. We are biased by our terrestrial perspective; (2) Ecologically significant dynamics happen at higher dimensions; and (3) Animals divert their flight/movement based on solar frame of reference. More to come on this one.
5) Nyeema Harris, a postdoc at University of California Berkeley, showed that carnivore extinction also causes extinction of parasites specialized on that host, which in turn increases the proportion of generalist parasites, many of which also parasitize humans. Thus, loss of big carnivores poses an indirect public health threat.