Learn More
Palaeontologists characterize mass extinctions as times when the Earth loses more than three-quarters of its species in a geologically short interval, as has happened only five times in the past 540 million years or so. Biologists now suggest that a sixth mass extinction may be under way, given the known species losses over the past few centuries and(More)
—The subfamily Equinae in the Great Plains region of North America underwent a dramatic radiation and subsequent decline as climate changed from warm and humid in the middle Miocene to cooler and more arid conditions during the late Miocene. Here we use ecological niche modeling (ENM), specifically the GARP (Genetic Algorithm using Rule-set Prediction)(More)
The horse subfamily Equinae underwent a major radiation during the Miocene in North America, diversifying from one species, Parahippus leonensis, to 70 species. This radiation has been linked to climatic and vegetation changes that occurred in North America during this time. However, the relationship between climate change and speciation has not previously(More)
Human impacts have left and are leaving distinctive imprints in the geological record. Here we show that in North America, the human-caused changes evident in the mammalian fossil record since c. 14,000 years ago are as pronounced as earlier faunal changes that subdivide Cenozoic epochs into the North American Land Mammal Ages (NALMAs). Accordingly, we(More)
An evaluation of the current status of two novel clusters, running Linux and NT, has been made to assess their performance for parallel CFD calculations. The core algorithm of the code is the conjugate gradient method used to solve the pressure equation. For good performance, a low latency and high bandwidth is required and the results indicate that,(More)
SUMMARY FLITE3D is a multigrid Euler solver. It is used extensively by British Aerospace in aircraft design and simulation. This paper presents experiences in parallelizing this industrial code. Owing to the employment of an agglomeration-based multigrid technique, the communication overhead on the coarser meshes could readily erode any gain from the use of(More)
Species distribution models (SDMs) assume species exist in isolation and do not influence one another's distributions, thus potentially limiting their ability to predict biodiversity patterns. Community-level models (CLMs) capitalize on species co-occurrences to fit shared environmental responses of species and communities, and therefore may result in more(More)
  • 1