Susumu Tomiya

Kyoto University | Kyodai · Center for International Collaboratioin and Advanced Studies in Primatology

We performed the ecometric analysis using the gear-ratio of calcaneus of artiodactyl fossils of the Tebingan fauna, comparing with the data of extant artiodactyls. The paleoenvironment of the Tebingan fauna was likely a predominantly evergreen environment with some grassland with relatively high precipitation throughout the year, indicating the sta...

Carnivoraforms (crown carnivorans and their closest relatives) first occupied hypercarnivorous niches near the dawn of the late Eocene, 40–37 Ma. This followed the decline or extinction of earlier carnivorous groups, Mesonychia and Oxyaenodonta, leaving carnivoraforms and hyaenodontan meat-eaters as high trophic level consumers. The pattern of this...

Despite the rising emphasis on STEM (science, technology, engineering, and mathematics) education in the last two decades, the United States has seen little change in student performance, based on international assessments. Transforming science education from the more traditional, lecture-format classes to inquiry-driven exercises is central for im...

The middle Eocene Washakie Formation of Wyoming, USA, provides a rare window, within a single depositional basin, into the faunal transition that followed the early Eocene warming events. Based on extensive examination, we report a minimum of 27 species of carnivorous mammals from this formation, more than doubling the previous taxic count. Include...

Macroevolutionary consequences of competition among large clades have long been sought in patterns of lineage diversification. However, mechanistically clear examples of such effects remain elusive. Here we postulated that the limited phenotypic diversity and insular gigantism in lagomorphs could be explained at least in part by an evolutionary con...

The Nimravidae were hypercarnivorous mammals first found in the middle Eocene. Filling cat-like morphological and ecological roles across the northern continents until the Miocene, nimravids were not cats at all, but have been interpreted as stem-feliforms or even as stem-carnivorans. The early phase of the clade’s evolutionary history in North Ame...

Museum of Comparative Zoology (MCZ) VPM-4225, a carnivoran dentary, is described here for the first time, 82 years after it was collected in the Duchesnean (late middle Eocene) portion of the Galisteo Formation in New Mexico. It evidently corresponds to the specimen—never identified by its catalog number, never described, and considered missing fo...

Despite rising emphasis on STEM education, public high-school students typically receive minimal exposure to historical biology/geology in school, and opportunities to participate in hands-on paleontological research and collections care are rare. We believe greater access to such opportunities will improve the public’s scientific literacy on biodi...

Recent advances in genomics and palaeontology have begun to unravel the complex evolutionary history of the gray wolf, Canis lupus Still, much of their phenotypic variation across time and space remains to be documented. We examined the limb morphology of the fossil and modern North American gray wolves from the late Quaternary (<ca 70 ka) to bette...

The Middle to Late Eocene sediments of Texas have yielded a wealth of fossil material that offers a rare window on a diverse and highly endemic mammalian fauna from that time in the southern part of North America. These faunal data are particularly significant because the narrative of mammalian evolution in the Paleogene of North America has tradit...

Abstract Mammalian body mass strongly correlates with life history and population properties at the scale of mouse to elephant. Large body size is thus often associated with elevated extinction risk. I examined the North American fossil record (28-1 million years ago) of 276 terrestrial genera to uncover the relationship between body size and extin...

The extinct group of carnivorous mammals that gave rise to the living mammalian order Carnivora (which today includes dogs, cats, and their relatives) are known as basal carnivoraforms. According to previous molecular and paleontological studies, the evolutionary history of this group during the middle Eocene (49 to 37 million years ago) holds a ke...

Background/Question/Methods The need for proactive approaches to mammalian conservation has precipitated efforts to identify biological correlates of extinction risk. Studies frequently point to life-history traits and ecological properties that are significantly correlated with body size as reliable predictors of species’ vulnerability to enviro...

Here we report on vertebrate fossil assemblages from two late Quaternary localities in the eastern San Francisco Bay region, Pacheco 1 and Pacheco 2. At least six species of extinct mammalian megaherbivores are known from Pacheco 1. The probable occurrence of Megalonyx jeffersonii suggests a late Pleistocene age for the assemblage. Pacheco 2 has yi...

List of comparative specimens examined. (DOC)

Measurements of the lower first molars of Lycophocyon hutchisoni, Hesperocyon gregarius, Urocyon cinereoargenteus townsendi, and Martes pennanti columbiana used for the analysis of size variation. (DOC)

Nexus file for the program Mesquite [144] containing the character matrix for the cladistic analysis, most-parsimonious trees for the full set of 50 OTUs (labeled as MPT50-1 through MPT50-132) and the subset consisting of 33 OTUs (labeled as MPT33-1 through MPT33-32), and the strict consensus for each set of taxa (labeled Consensus50 and Consensus3...

Despite a long history of research, the phylogenetic origin and initial diversification of the mammalian crown-group Carnivora remain elusive. Well-preserved fossil materials of basal carnivorans are essential for resolving these issues, and for constraining the timing of the carnivoran origin, which constitutes an important time-calibration point...

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 a...

The University of California Museum of Paleontology (UCMP) maintains the largest university museum fossil collection in the world and promotes research and education at its home, University of California, Berkeley, and far beyond. The museum supplies crucial materials and intellectual resources to a wide variety of university courses, where graduat...