17 research outputs found
Recommended from our members
A bibliography of Oregon mammalogy
Published March 1982. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalo
Mammal collections of the Western Hemisphere: A survey and directory of collections
As a periodic assessment of the mammal collection resource, the Systematic Collections Committee (SCC) of the American Society of Mammalogists undertakes decadal surveys of the collections held in the Western Hemisphere. The SCC surveyed 429 collections and compiled a directory of 395 active collections containing 5,275,155 catalogued specimens. Over the past decade, 43 collections have been lost or transferred and 38 new or unsurveyed collections were added. Growth in number of total specimens, expansion of genomic resource collections, and substantial gains in digitization and web accessibility were documented, as well as slight shifts in proportional representation of taxonomic groups owing to increasingly balanced geographic representation of collections relative to previous surveys. While we find the overall health of Western Hemisphere collections to be adequate in some areas, gaps in spatial and temporal coverage and clear threats to long-term growth and vitality of these resources have also been identified. Major expansion of the collective mammal collection resource along with a recommitment to appropriate levels of funding will be required to meet the challenges ahead for mammalogists and other users, and to ensure samples are broad and varied enough that unanticipated future needs can be powerfully addressed. © 2018 The Author(s)
Fossil History of Notiosorex (Soricomorpha: Soricidae) Shrews with Descriptions of New Fossil Species
Notiosorex shrews (Soricomorpha; Soricidae) have a fossil history that extends to the Miocene (i.e., mid-Hemphillian), In the intervening 6.69 million years, N. repenningi, N. jacksoni, and what heretofore was considered N. crawfordi existed with varying degrees of overlap in occurrence timewise and in geographic distribution in areas of the southwestern United States and northern Mexico. Examination of unusually small fossil specimens of Notiosorex indicated the presence of another species referable to this genus present in late Pleistocene- (i.e., early Wisconsinan) to Holocene-aged deposits. Based on statistical analyses, these specimens were as distinct from any of the other fossil or extant species of Notiosorex as any other pair of species within the genus. I referred these specimens to the new species N. harrisi. Analyses also indicted fossils heretofore considered N. crawfordl were equally distinct from other forms of Notiosorex. I referred them to the new species N. dalquesti. Individuals referred to the fossil species of Notiosorex range in size from the smaller N. harrisi, to N. dalquesti, to N. jacksoni, to the larger N. repenningi. This size differential could be related to changing climatic conditions with the concomitant ecological succession that occurred, which provided a driving force for speciation within the genus. The changing climate and unique morphological and physiological adaptations allowed fossil taxa of Notiosorex to expand their distributions into areas subsequently less suitable for other forms of shrews, Present-day notiosoricini shrews occur throughout much of the southwestern United States and northern Mexico in a variety of habitats in association with rough, rocky terrain. Thus, if climate, even indirectly, was the driving force for speciation among fossil taxa of Notiosorex, other forces must have acted on the extant species N. cockrumi, N. crawfordl, N. evotis, and N. villai
Recommended from our members
A morphologic and morphometric analysis of the "Sorex vagrans species complex" in the Pacific Coast region
Shrews of the "Sorex vagrans species complex" were classified into
nine taxa on the basis of morphologic and morphometric analyses of
2,299 specimens from Washington, west of the Cascade Mountains in
Oregon, and in the Coast Ranges of California. In Washington, Sorex
monticolus setosus and S. m. obscurus occur west and east of the
Cascade Mountains, respectively. Oregon specimens heretofore
considered S. m. bairdii were shown to possess morphometric differences
sufficient to indicate they were specifically distinct from S.
monticolus in Washington. The Columbia River may have acted as a
barrier that led to a speciation event separating bairdii and
monticolus. Seven specimens from Oregon, referred to S. m. setosus,
were collected within 27 km of a landslide that dammed the Columbia
River about 740 years ago. The slide probably was responsible for
introduction of the taxon into Oregon. Holotypes of S. yaquinae (= S.
pacificus yaquinae) and S. pacificus appear morphologically identical
(the latter is damaged), thus the taxa were synonomized; the latter
species name has priority. These shrews occur in the Oregon Coast
Range from Taft, Lincoln Co., to Coquille, Coos Co., eastward to H. J.
Andrews Experimental Forest, Linn Co., southward in the Cascade
Mountains to near the California border. Sorex pacificus (= S. E.
yaguinae) is morphometrically distinct from bairdii with which it is
sympatric in the northern portion of its geographic range. Also, it is
morphometrically distinct from shrews heretofore considered S. p.
sonomae and S. p. pacificus and sympatric in the southern portion of
its range with shrews formerly assigned to the latter taxon.
Geographic variation within sonomae and pacificus is sufficient to
warrant application of distinct trinomials to both taxa. Within my
study area, S. vagrans exhibits no discernable geographic subunits.
For all taxa, except S. vagrans, I found a relationship between
latitude and the size of the projection on the medial edge of the first
upper incisors from largest in the north to no projection in the south.
This relationship likely is related to substantial differences in
temperature, precipitation, and associated environmental factors over
the 1,250 km from northern Washington south to San Francisco Bay,
California. The southward reduction and ultimate loss of the median
tine combined with the progressive enlargement of several skull
characters associated with greater masticatory ability strongly
suggests a dietary function for the median tine. Thus, changes in food
resources of shrews in a southward direction in relation to increasing
aridity and high temperatures possibly was the selective force
responsible for reduction or loss of tines in southern taxa
Revision of the extant taxa of the genus Notiosorex (Mammalia: Insectivora: Soricidae)
We evaluated the taxonomic status of three specimens of gray shrews, Notiosorex (Insectivora: Soricidae), collected in isolated mountain valleys in Tamaulipas, Mexico, with specimens referable to the Recent taxa N. crawfordi crawfordi (n = 229) and N. c. evotis (n = 34). Statistical analyses of cranial morphometric data revealed that the specimens from Tamaulipas represented a heretofore unknown taxon which is described herein as a new species of Notiosorex (N. villai). Also, N. c. evotis was found to be equally distinct from N. c. crawfordi, thus was elevated to specific status.
Resumen---Se evaluó el estado taxonómico de tres especímenes de la musaraña gris Notiosorex (Insectivora: Soricidae), colectados en valles dentro de las motañas en Tamaulipas, México y referidos a los taxa recientes N. crawfordi crawfordi (n = 229) y N. c. evotis (n = 34). Análisis estadísticos morfométricos del cráneo indicaron que los especímenes de Tamaulipas representan un taxón desconocido, el cual se describe como una especie nueva de Notiosorex (N. villai). Asimismo, N. c. evotis se encontró distinto a N. c. crawfordi, por lo que se elevó aI nivel específico
Land mammals of Oregon
This is the first comprehensive, up-to-date treatment of mammals in the state of Oregon since 1936, when Vernon Bailey's The Mammals and Life Zones of Oregon was published. It provides a basic reference for mammalogists, wildlife biologists, students, and anyone interested in mammalian life in the northwestern United States. Indeed, researchers in states adjacent to Oregon will find much useful information regarding the mammals their regions share with Oregon. Descriptions of all 136 extant or recently extirpated mammal species in Oregon are in the book, with information on geographical variation, diet, reproduction, ontogeny, mortality, and behavior. The authors provide range maps and lists of collection localities based on their examination of 55,265 museum specimens and brief accounts of morphology, species diversity, distribution, and fossil records. Keys to orders, families, and species are provided for identification of unknown specimens. Also helpful is the introductory section with its discussion of skull morphology, evolutionary history, basic taxonomy, zoogeography, zoonotic diseases, and the history of mammalogy in Oregon. A bibliography of 2,925 references makes the volume especially useful for anyone wishing to do further research
DISPERSAL AND DISPERSION OF AN INTRODUCED POPULATION OF SYLVILAGUS FLORIDANUS
Volume: 41Start Page: 167End Page: 17