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The last important –and possibly the most spectacular– turnover in South American mammal history occurred around the Pleistocene-Holocene boundary, when 100% of megamammal species and about 80% of large mammal specie...

The parameterized extinction data of Fitzpatrick and Massa (1986, 1988) for the ultraviolet and various sources for the optical and near-infrared are used to derive a meaningful average extinction law over the 3.5 micron...

"We investigate the relationship between the nested organization of mutualistic systems and their robustness against the extinction of species. We establish that a nested pattern of contacts is the best possible one as f...

During the latest Pleistocene-earliest Holocene, South American terrestrial vertebrate faunas suffered one of the largest (and probably the youngest) extinction in the world for this lapse. Megamammals, most of the large...

The optical properties of metal nanoparticles have long been of interest in physical chemistry, starting with Faraday's investigations of colloidal gold in the middle 1800s. More recently, new lithographic techniques as ...

We present a full-sky 100 km map that is a reprocessed composite of the COBE/DIRBE and IRAS/ ISSA maps, with the zodiacal foreground and conrmed point sources removed. Before using the ISSA maps, we remove the remaining ...

Low resolution spectra in the λλ3500-4600 Å wavelength range of 23 stars with the B[e] phenomenon are presented. Spectral classification of 15 program stars was performed using the BCD spectrophotometric system, based...

The present study includes a review of the geographic and stratigraphic distribution of short-faced bears (Ursidae, Tremarctinae) in South America. In addition, the authors discuss biogeographic hypotheses regarding the ...

Context. We present the second Gaia data release, Gaia DR2, consisting of astrometry, photometry, radial velocities, and information on astrophysical parameters and variability, for sources brighter than magnitude 21. In...

Leon Festinger's theory of cognitive dissonance has been widely recognized for its important and influential concepts in areas of motivation and social psychology. The theory of dissonance is here applied to the problem ...

Human alteration of Earth is substantial and growing. Between one-third and one-half of the land surface has been transformed by human action; the carbon dioxide concentration in the atmosphere has increased by nearly 30...

We present spectral and photometric observations of 10 Type Ia supernovae (SNe Ia) in the redshift range 0.16 z 0.62. The luminosity distances of these objects are determined by methods that employ relations between SN I...

Biogeography was stuck in a "natural history phase" dominated by the collection of data, the young Princeton biologists Robert H. MacArthur and Edward O. Wilson argued in 1967. In this book, the authors developed a gener...