Mass extinction of Pacific Island Birds
Research Assistant Professor Alison Boyer was interviewed today on local NPR station WUOT about her recent PNAS paper about extinctions of birds on Pacific islands. The interview can be heard here.
by armsworth
Research Assistant Professor Alison Boyer was interviewed today on local NPR station WUOT about her recent PNAS paper about extinctions of birds on Pacific islands. The interview can be heard here.
by artsciweb
Alison Boyer, Research Assistant Professor in the UTK EEB department, recently coauthored a paper in PNAS on the drivers and hotspots of extinction risk in marine mammals.
Abstract:
The world’s oceans are undergoing profound changes as a result of human activities. However, the consequences of escalating human impacts on marine mammal biodiversity remain poorly understood. The International Union for the Conservation of Nature (IUCN) identifies 25% of marine mammals as at risk of extinction, but the conservation status of nearly 40% of marine mammals remains unknown due to insufficient data. Predictive models of extinction risk are crucial to informing present and future conservation needs, yet such models have not been developed for marine mammals. In this paper, we: (i) used powerful machine-learning and spatial-modeling approaches to understand the intrinsic and extrinsic drivers of marine mammal extinction risk; (ii) used this information to predict risk across all marine mammals, including IUCN “Data Deficient” species; and (iii) conducted a spatially explicit assessment of these results to understand how risk is distributed across the world’s oceans. Rate of offspring production was the most important predictor of risk. Additional predictors included taxonomic group, small geographic range area, and small social group size. Although the interaction of both intrinsic and extrinsic variables was important in predicting risk, overall, intrinsic traits were more important than extrinsic variables. In addition to the 32 species already on the IUCN Red List, our model identified 15 more species, suggesting that 37% of all marine mammals are at risk of extinction. Most at-risk species occur in coastal areas and in productive regions of the high seas. We identify 13 global hotspots of risk and show how they overlap with human impacts and Marine Protected Areas.
by artsciweb
Alison Boyer, a new Research Assistant Professor in EEB, just published a paper in last week’s issue of Science.
The Evolution of Maximum Body Size of Terrestrial Mammals
Felisa A. Smith, Alison G. Boyer, James H. Brown, Daniel P. Costa, Tamar Dayan,
S. K. Morgan Ernest, Alistair R. Evans, Mikael Fortelius, John L. Gittleman,
Marcus J. Hamilton, Larisa E. Harding, Kari Lintulaakso, S. Kathleen Lyons,
Christy McCain, Jordan G. Okie, Juha J. Saarinen, Richard M. Sibly, Patrick R. Stephens, Jessica Theodor, Mark D. Uhen
Science 330, 1216 (2010);
DOI: 10.1126/science.1194830
Abstract:
The extinction of dinosaurs at the Cretaceous/Paleogene (K/Pg) boundary was the seminal event that opened the door for the subsequent diversification of terrestrial mammals. Our compilation of maximum body size at the ordinal level by sub-epoch shows a near-exponential increase after the K/Pg. On each continent, the maximum size of mammals leveled off after 40 million years ago and thereafter remained approximately constant. There was remarkable congruence in the rate, trajectory, and upper limit across continents, orders, and trophic guilds, despite differences in geological and climatic history, turnover of lineages, and ecological variation. Our analysis suggests that although the primary driver for the evolution of giant mammals was diversification to fill ecological niches, environmental temperature and land area may have ultimately constrained the maximum size achieved.
by artsciweb
Alison Boyer, a new Research Assistant Professor in EEB, just published a paper in last week’s issue of Science.
The Evolution of Maximum Body Size of Terrestrial Mammals
Felisa A. Smith, Alison G. Boyer, James H. Brown, Daniel P. Costa, Tamar Dayan,
S. K. Morgan Ernest, Alistair R. Evans, Mikael Fortelius, John L. Gittleman,
Marcus J. Hamilton, Larisa E. Harding, Kari Lintulaakso, S. Kathleen Lyons,
Christy McCain, Jordan G. Okie, Juha J. Saarinen, Richard M. Sibly, Patrick R. Stephens, Jessica Theodor, Mark D. Uhen
Science 330, 1216 (2010);
DOI: 10.1126/science.1194830
Abstract:
The extinction of dinosaurs at the Cretaceous/Paleogene (K/Pg) boundary was the seminal event that opened the door for the subsequent diversification of terrestrial mammals. Our compilation of maximum body size at the ordinal level by sub-epoch shows a near-exponential increase after the K/Pg. On each continent, the maximum size of mammals leveled off after 40 million years ago and thereafter remained approximately constant. There was remarkable congruence in the rate, trajectory, and upper limit across continents, orders, and trophic guilds, despite differences in geological and climatic history, turnover of lineages, and ecological variation. Our analysis suggests that although the primary driver for the evolution of giant mammals was diversification to fill ecological niches, environmental temperature and land area may have ultimately constrained the maximum size achieved.