Frontotemporal lobar degeneration progresses more rapidly than Alzheimer disease, and the fastest-progressing cases are those with the frontotemporal dementia clinical subtype, coexisting motor neuron disease, or tau-negative neuropathology.

True primates appeared suddenly on all three northern continents during the 100,000-yr-duration Paleocene-Eocene Thermal Maximum at the beginning of the Eocene, Ϸ55.5 mya. The simultaneous or nearly simultaneous appearance of euprimates on northern continents has been difficult to understand because the source area, immediate ancestors, and dispersal routes were all unknown. Now, omomyid haplorhine Teilhardina is known on all three continents in association with the carbon isotope excursion marking the Paleocene-Eocene Thermal Maximum. Relative position within the carbon isotope excursion indicates that Asian Teilhardina asiatica is oldest, European Teilhardina belgica is younger, and North American Teilhardina brandti and Teilhardina americana are, successively, youngest. Analysis of morphological characteristics of all four species supports an Asian origin and a westward Asia-toEurope-to-North America dispersal for Teilhardina. High-resolution isotope stratigraphy indicates that this dispersal happened in an interval of Ϸ25,000 yr. Rapid geographic dispersal and morphological character evolution in Teilhardina reported here are consistent with rates observed in other contexts.carbon isotope excursion ͉ euprimates ͉ omomyids

Semantic dementia is associated with significantly more behavioral dysfunction than other variants of primary progressive aphasia, specifically behavioral features typical of frontotemporal dementia.

The fossil mammals of the lower Eocene part of the Willwood Formation in the southern Bighorn Basin of northwest Wyoming constitute by far the largest sample of stratigraphically documented fossil mammals of any age from anywhere in the world. For this reason, the southern Bighorn Basin Willwood sample of fossil vertebrates has become the most important for empirically derived paleontological studies of tempo and mode of evolution in Mammalia. Locality data for 1,472 Willwood fossil mammal sites (about 1,146 hitherto unpublished) and the detailed Stratigraphic correlation of 941 of them into measured Stratigraphic sections (700 newly correlated) afford a framework for the biostratigraphic integration of nearly 80,000 catalogued and at least 30,000 uncatalogued specimens. Earlier published and unpublished measured sections of the Willwood Formation of the central and southern Bighorn Basin that related fossil mammal localities to one another are partly revised; all are tied to a new master section. Revisions to earlier sections do not materially affect published accounts of the principally gradual nature of evolution of Willwood mammals. A preliminary list of the Willwood mammal fauna of the southcentral and southeast Bighorn Basin and mammalian compositions for some of the most important sites are presented. Locality and Stratigraphic correlations are also provided for 37 fossil plant localities in the Fort Union, Willwood, and Tatman Formations, data that offer considerable potential for correlation of late Paleocene and early Eocene plant and mammal biostratigraphies. Fossil pollen also permits direct correlation of Willwood rocks with standard marine zonations.

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2015): Craniodental and postcranial morphology of Indohyaenodon raoi from the early Eocene of India, and its implications for ecology, phylogeny, and biogeography of hyaenodontid mammals, Journal of Vertebrate PaleontologyTo link to this article: http://dx.ABSTRACT-New remains of the early Eocene hyaenodontid Indohyaenodon raoi are described from the Vastan Lignite Mine in Gujarat, western India, including the first known rostrum, upper dentition, and postcrania, substantially expanding our knowledge of the species and providing insights into its functional morphology and relationships. Craniodental morphology suggests that I. raoi had a broad diet, including non-vertebrate material as well as flesh of a diversity of prey species. Postcranial morphology is broadly similar to that of other early hyaenodontids and suggests a scansorial locomotor repertoire. Dental morphology indicates that I. raoi is closely related to other South Asian hyaenodontids, with shared features including strong cingula, narrow premolars, and a reduced P4 protocone. We present the most comprehensive phylogenetic analysis of Hyaenodontidae to date, which corroborates this relationship but finds South Asian hyaenodontids to be the stem of a group that includes most African hyaenodontids. This and other higher-level relationships within Hyaenodontidae are, however, weakly supported, and substantially different alternative hypotheses of relationships are not significantly less parsimonious, reflecting strong character conflict. Factors contributing to this conflict include the isolation of hyaenodontid faunas on different continents during much of the Eocene, canalization and simplification of carnivorous dentitions, and a lack of non-dental material for critical hyaenodontid groups. The new phylogeny is consistent with either an African or an Asian origin for the group.

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