Mammalogy Papers: University of Nebraska State Museum Copyright (c) 2013 University of Nebraska - Lincoln All rights reserved. http://digitalcommons.unl.edu/museummammalogy Recent documents in Mammalogy Papers: University of Nebraska State Museum en-us Tue, 02 Apr 2013 10:51:49 PDT 3600 Examination of Annual Variation in the Adult Sex Ratio of Pronghorn (<i>Antilocapra americana</i>) http://digitalcommons.unl.edu/museummammalogy/161 http://digitalcommons.unl.edu/museummammalogy/161 Tue, 06 Nov 2012 06:47:08 PST The adult sex ratio (ASR) is an important component of a population’s demographics and can be used as an indicator of a population’s status. However, the causes of annual variation in ASRs are unknown for many species. Fluctuations in ASR can arise through demographic stochasticity and intense selective harvesting. In this study we investigate the longterm patterns of variation in the ASRs (bucks: 100 does) for four populations of pronghorn (Antilocapra americana) in western Nebraska. We used multiple variables in a model selection process to predict annual fluctuation of pronghorn ASRs. We found that the number of bucks: 100 does significantly varied over the four populations. The best predictors of annual variation in pronghorn ASRs were variable across all populations. The number of pronghorn bucks harvested in the previous year’s hunting season and the previous year’s density of pronghorn were the most common predictors of ASR fluctuation. Buck harvest was an important predictor variable in only two of the four populations. Variation of harvest strategies within the populations could account for the lack of importance of buck harvest in half of the populations. The relationship between density and ASR is novel but difficult to interpret due to lack of data on birth sex ratios and fawn survival. More data on pronghorn demographics are needed in order to better explain the connection between density and ASR.

]]> Justin D. Hoffman et al. Genetic Diversity of Neotropical <i>Myotis</i> (Chiroptera: Vespertilionidae) with an Emphasis on South American Species http://digitalcommons.unl.edu/museummammalogy/160 http://digitalcommons.unl.edu/museummammalogy/160 Thu, 04 Oct 2012 06:32:48 PDT Background: Cryptic morphological variation in the Chiropteran genus Myotis limits the understanding of species boundaries and species richness within the genus. Several authors have suggested that it is likely there are unrecognized species-level lineages of Myotis in the Neotropics. This study provides an assessment of the diversity in New World Myotis by analyzing cytochrome-b gene variation from an expansive sample ranging throughout North, Central, and South America. We provide baseline genetic data for researchers investigating phylogeographic and phylogenetic patterns of Myotis in these regions, with an emphasis on South America.

Methodology and Principal Findings: Cytochrome-b sequences were generated and phylogenetically analyzed from 215 specimens, providing DNA sequence data for the most species of New World Myotis to date. Based on genetic data in our sample, and on comparisons with available DNA sequence data from GenBank, we estimate the number of species-level genetic lineages in South America alone to be at least 18, rather than the 15 species currently recognized.

Conclusions: Our findings provide evidence that the perception of lower species richness in South American Myotis is largely due to a combination of cryptic morphological variation and insufficient sampling coverage in genetic-based systematic studies. A more accurate assessment of the level of diversity and species richness in New World Myotis is not only helpful for delimiting species boundaries, but also for understanding evolutionary processes within this globally distributed bat genus.

]]> Roxanne J. Larsen et al. Analysis of Sonagrams of American Bison (<i>Bison Bison</i>) http://digitalcommons.unl.edu/museummammalogy/159 http://digitalcommons.unl.edu/museummammalogy/159 Wed, 28 Mar 2012 13:26:09 PDT The sound made by adult male American bison (Bison bison) during agonistic behavior has been described as a "roar" because of its similarity to the roar of an African lion (Shult, 1972). Bulls roar any time of the year, but more commonly and most intensively during the rut when there are many agonistic confrontations between competing males. McHugh (1958), Shult (1972), and Petersburg (1973) have described this roaring and under what circumstances it occurs.

While the bull is roaring, its tongue is protruded and the sound is produced by forceful expiration of air over the vocal cords. In contrast, the "mooing" and loud "bawling" or "bellowing" of domestic cows and bulls (Bos taurus) are produced by both expiration and inspiration of air over the vocal cords (Kelemen, 1963).

The basic sound made by bison is a grunt. This varies from the barely audible vocalization of young calves to the loud roaring of the bulls. Although more common among bison bulls, cows protecting their newborn calves also roar (Mahan, 1978), but not as loudly as bulls. Sounds usually made by bison cows consist of soft gutteral grunts. Calves produce higher pitched grunts, often in response to their dam's somewhat louder grunting. Calves also bleat loudly, usually during active chases and play fights with other calves. Grunting occurs at all times of the year, but more frequently when the calves are very young and again when the calves begin leaving the cow and forming subgroups within the herd. McHugh (1958) discussed the function and occurrence of the sounds made by bison cows and calves. In general, their vocalizations are comparable in sound and function to that of domestic cows and calves.

]]> Harvey L. Gunderson et al. Bats of Barbados http://digitalcommons.unl.edu/museummammalogy/158 http://digitalcommons.unl.edu/museummammalogy/158 Wed, 28 Mar 2012 13:21:08 PDT The chiropteran fauna of Barbados includes representatives of four families — Noctilionidae, Phyllostomidae, Vespertilionidae, and Molossidae — including 1 piscivore (Noctilio leporinus), 1 omnivore (Brachyphylla cavernarum), 1 pollenivore/nectarivore (Monophyllus plethodon), 1 frugivore (Artibeus jamaicensis), and 2 insectivorous species (Myotis nyctor and Molossus molossus). Despite an early report, we believe that preponderance of the evidence available at this time is that E. fuscus is not part of the fauna of Barbados. The Barbadian chiropteran fauna of 6 species is much smaller than those on the four neighboring Lesser Antillean islands to the west and north. We believe that this is primarily the result of two factors—geological age and geographic isolation. Our work indicates that populations of the 6 species of bats on Barbados are in good condition in all cases, but only for Artibeus jamaicensis and Molossus molossus are the populations large enough to not be of ongoing concern. The maintenance of the chiropteran fauna can best be served by three management actions — preservation of caves and associated gullies, forests, and hydrological systems.

]]> Hugh H. Genoways et al. Habitat of Red-Backed Vole http://digitalcommons.unl.edu/museummammalogy/157 http://digitalcommons.unl.edu/museummammalogy/157 Wed, 28 Mar 2012 13:13:12 PDT These data are a part of a study of small mammal populations at Cedar Creek Forest, Anoka County, Minnesota. The live-trapping area of 5.0 acres, with 81 traps spaced 52 feet apart, was in a tamarack-white cedar bog. The study extended over a period of 7 years (1949-1955). Trapping periods of five days (four nights) extended from early May to the first part of October. In all, there were 14,580 trap-nights. A total of 428 voles were marked and weighed; data on 25 dead unmarked individuals are also included.

A frequency index was calculated for each station. This index was arrived at by multiplying the number of individuals caught at a station by the number of years they occurred at that station. These indices were grouped and represented on a map. Clethrionomys occupied mostly the white cedar area with sparse to medium cover. Within this area their distribution was most closely correlated with the presence of stumps, rotting logs and root systems in loose forest litter and sphagnum.

]]> Harvey L. Gunderson Mammal Observations at Lower Back River, Northwest Territories, Canada http://digitalcommons.unl.edu/museummammalogy/156 http://digitalcommons.unl.edu/museummammalogy/156 Wed, 28 Mar 2012 13:05:25 PDT The Back River drains the interior barrens of the Northwest Territories of Canada. According to Blanchet (1930) the river has its headwaters in a high plateau and flows through a sand plain basin (not in accord with conditions of our base camp). The country north of the Back River drainage is of low relief. The river takes a northerly direction for the last one-third of its course. To the east, between the river and Wager Bay, the country is known to be very rugged.

The first known exploration of the Back River, then called the Great Fish River, was by Sir George Back and his party, who left England in 1833 to search for Sir John Ross. Back's party wintered at Ft. Reliance. During the summer of 1834 they went down the Back River to its mouth and returned to Ft. Reliance where they again spent the winter, returning to England in 1835. In the appendix of Back's report (1836) there is a list of specimens collected and observed. The collecting was done by Mr. Richard King, surgeon to the expedition.

In 1855 Chief Factor James Anderson of the Hudson's Bay Company made a similar journey (Clarke, 1940a) hoping to find traces of the ill-fated Franklin Expedition. Both these exploring trips support Stefansson's statement (1929) that much arctic exploration has been a by-product of search parties.

So far as is known, Back and Anderson and their parties were the only white men who had visited in summer the area selected for the University of Minnesota- Wilkie Foundation expedition to the Back River. Members of the expedition were Dr. W. J. Breckenridge, Harvey L. Gunderson, John A. Jarosz, R. Spence Taylor, Robert J. Wilkie, James W. Wilkie and Dr. Lawrence Larson. The party was in the vicinity of Mount Meadowbank along the Back River from July 13 to August 6, 1953.

Our camp was located at an elevation of about 150 feet above sea level on a bay of the Back River at 66°10' N. latitude and 96°57' W. longitude, about 125 miles northwest of Baker Lake. The topography in the vicinity of camp was undulating with many high hills. The highest of these was Mount Meadowbank with an altitude of 570 feet. Some of the hills were composed of metamorphosed rock outcrops, others of rubble dumped by retreating glaciers, and eskers of many miles in length were not uncommon. The surface of the hills was covered with material ranging in size from gravel to desk-sized boulders, most often one or the other, rarely both.

Those valleys and depressions not filled with water, had carpets of sedge and moss-covered peaty tussocks. There were innumerable small lakes. Two factors cause poor drainage in the Barren Grounds. One is the presence of permafrost, the other is that the youth of the land has not yet allowed for the development of permanent stream and river valleys, with the exception of the large rivers. Arctic soils are generally acidic because of this poor drainage and poor aeration. Organic decay by bacterial action is extremely slow due to the low temperatures. Consequently, nitrogen and salts needed by plants are rather scarce.

]]> H. L. Gunderson et al. Red-Backed Vole with a Tick Attached Near Eyeball http://digitalcommons.unl.edu/museummammalogy/155 http://digitalcommons.unl.edu/museummammalogy/155 Wed, 28 Mar 2012 12:54:14 PDT A red-backed vole (Clethrionomys gapperi), with a tick attached to or just under the inner corner of the eyelid at the canthus, was caught in a live trap on July 11, 1961. This is an unusual place of attachment and it is difficult to understand how the tick could have become attached at a point where it could easily be scratched off by either the forefoot or hind foot of the vole.

]]> H. L. Gunderson The Lemming Vole, <i>Synaptomys borealis</i>, in Northern Minnesota http://digitalcommons.unl.edu/museummammalogy/153 http://digitalcommons.unl.edu/museummammalogy/153 Wed, 14 Mar 2012 14:34:18 PDT Lemming voles of the subgenus Mictomys have never been recorded from north-central United States, although they might be expected to occur there judging from records of the species Synaptomys (Mictomys) borealis from southern Manitoba. Recently, examination of specimens in the collection of the Minnesota Museum of Natural History reveals that Synaptomys borealis does occur in north-central United States for we have found the following specimens referable to that species: one immature female (No. 951, MMNH) from Williams, Lake of the Woods County, Minnesota, collected by Gustav Swanson, August 5, 1932; one adult male (No. 2552, MMNH) from Warroad, Roseau County, Minnesota, collected by H. L. Gunderson and B. J. Hayward, July 27,1948.

]]> Ralph M. Wetzel et al. Mule Deer Record for Minnesota http://digitalcommons.unl.edu/museummammalogy/152 http://digitalcommons.unl.edu/museummammalogy/152 Wed, 14 Mar 2012 14:31:37 PDT During the hunting season of 1947, Leonard Nygren shot a deer near Pillager, Cass County, Minnesota. The deer, which weighed 153 pounds dressed, was disqualified in a sportsman's contest because it was not considered a white-tailed deer, according to a newspaper report. The report was investigated and the animal in question was identified as a mule deer, Odocoileus hemionus. This extends the known range of this deer in Minnesota nearly 100 miles to the east. John Jarosz, Museum Preparator, and the writer went to Nygren's place nine miles north of Pillager and measured and skinned the animal which is now specimen number 2457 in the Minnesota Museum of Natural History collection. The . total length of the animal was 72 inches, the ears were 10 inches, the metatarsal gland was 7 inches long, and the tail had a black tip. The vertical tine of the antler was not dichotomously branched, although quite long.

]]> Harvey L. Gunderson Evolutionary history of Caribbean species of <i>Myotis</i>, with evidence of a third Lesser Antillean endemic http://digitalcommons.unl.edu/museummammalogy/151 http://digitalcommons.unl.edu/museummammalogy/151 Thu, 08 Mar 2012 12:25:52 PST Currently, four species of Myotis are known from the islands of the Caribbean (Myotis dominicensis, M. martiniquensis, M. nesopolus, and M. nigricans). Myotis dominicensis and M. martiniquensis are endemic to the Lesser Antilles, whereas M. nesopolus and M. nigricans are considered conspecific with mainland populations. Recent phylogenetic and phylogeographic studies provided hypotheses regarding the origin and diversification of M. dominicensis and M. martiniquensis. However, these studies focused primarily on convergent morphology or distribution patterns of this genus and not on the evolutionary history of Caribbean Myotis. Here, we explore variation across multiple datasets generated from Caribbean Myotis. We present morphologic and genetic (mitochondrial and nuclear) data from an extensive sample of Caribbean Myotis species, including the previously unsampled taxa M. martiniquensis nyctor and M. nesopolus. Our data indicate that the historically recognized subspecies M. m. nyctor is genetically and morphologically distinct from M. martiniquensis, warranting recognition of a third Caribbean endemic—Myotis nyctor. Moreover, we provide evidence of unrecognized species-level variation in Caribbean and northern South American populations of Myotis.

]]> Roxanne J. Larsen et al. Factors influencing long-term population dynamics of pronghorn (<i>Antilocapra americana</i>): evidence of an Allee effect http://digitalcommons.unl.edu/museummammalogy/150 http://digitalcommons.unl.edu/museummammalogy/150 Tue, 14 Feb 2012 07:35:04 PST Populations of pronghorn (Antilocapra americana) are subjected to multiple forms of density-dependent and density-independent regulation. Little is known about the combined effects of these variables across multiple populations throughout the landscape. The objectives of this study were to examine long-term trends in density and recruitment in pronghorn and to assess how different forms of regulation influence these trends. We used multiple density-dependent and density-independent explanatory variables in a model selection process to explain variation in pronghorn density and July fawn : doe ratios from 1955 to 1993 in 4 pronghorn management units in Nebraska. We also investigated levels of density-dependent feedback in each management unit. Examination of long-term population trends suggested that pronghorn populations in Nebraska exhibited an Allee effect (inverse density dependence), in which population growth decreases as density decreases. We suggest that variation in rangeland condition and presence of adequate forage could explain the presence of the Allee effect. Both density-dependent and density-independent variables affected pronghorn populations, with density of cattle, spring precipitation, abundance of winter wheat, and hunting harvest most important for explaining fluctuations in pronghorn densities. Snow depth and density of cattle best explained yearly July fawn : doe ratios. The importance of each factor was variable across the different management units. Management objectives aimed at improving access to and abundance of food resources during times when rangeland condition is poor could prevent drastic declines in pronghorn populations.

]]> Justin D. Hoffman et al. HISTORICAL BIOGEOGRAPHY OF NEBRASKA PRONGHORNS (<i>ANTILOCAPRA AMERICANA</i>) http://digitalcommons.unl.edu/museummammalogy/149 http://digitalcommons.unl.edu/museummammalogy/149 Tue, 14 Feb 2012 07:30:25 PST Archeological and paleontological records indicate that the pronghorn (Antilocapra americana) have a history of at least 20,000 years of occurrence within the current boundaries of Nebraska. Pronghorns occurred throughout the state for much of its history. With the evidence at hand we concluded that the eastern boundary of the geographic distribution of the pronghorn south of the Niobrara River in Nebraska at the beginning of the 19th century was along the western perimeter of the eastern deciduous forest and tallgrass prairie. This excluded most of the easternmost tier of counties in the state. This geographic arrangement persisted throughout most of the Holocene. The boundary, however, was never a straight line, but a dynamic system of fluctuating distribution. By the early 20th century, the pronghorn was nearly extirpated from Nebraska, with only scattered herds in the western panhandle. With a ban on hunting beginning in 1907 and management by the Nebraska Game and Parks Commission, the population in the panhandle had increased to the point that a hunting season was reinstituted in 1953. To establish herds of pronghorns in previously occupied areas beyond the panhandle, 1,106 individuals were translocated between 1958 and 1962 primarily to the Sandhills region of Nebraska. Currently, the pronghorn possess stable populations throughout nearly half of Nebraska, including the panhandle and most of the Sandhills.

]]> Justin D. Hoffman et al. OBITUARY: JERRY RONALD CHOATE, 1943–2009 http://digitalcommons.unl.edu/museummammalogy/148 http://digitalcommons.unl.edu/museummammalogy/148 Tue, 14 Feb 2012 07:24:31 PST Jerry Ronald Choate (1943–2009) had just retired as Director of the Sternberg Museum of Natural History and Professor of Biological Sciences, Fort Hays State University, Hays, Kansas, at the time of his death. Jerry served the American Society of Mammalogists in numerous capacities, including Recording Secretary, First Vice President, and most notably as a member and chair of the Board of Trustees.

The hallmark of Jerry’s life was to turn the ordinary into something magnificent. Whether it was his photography that changed an ordinary landscape into a magnificent masterpiece, or his convincing a reluctant graduate student that they could do good science, assistant professors that they could be good mentors, colleagues that they could do good science, it was always the same. He exuded quiet confidence that it could be done with hard work and perseverance. In many ways Jerry Choate was both ‘‘one of a kind’’ and an ‘‘exemplar’’ of his generation of field mammalogists. His personality was both complex and multilayered on the one hand, while straightforward ‘‘eyes on the road’’ on the other hand. Jerry Choate’s huge and lasting successes in education, science, and university and community development probably exceeded his expectations for himself but were inevitable, given his dogged determination and work ethic. Jerry was a finisher.

]]> Elmer J. Finck et al. Karyotypes of Shrews of the Genera <i>Cryptotis</i> and <i>Blarina</i> (Mammalia: Soricidae) http://digitalcommons.unl.edu/museummammalogy/147 http://digitalcommons.unl.edu/museummammalogy/147 Tue, 14 Feb 2012 07:06:55 PST Cryptotis parva has a diploid number of 52 and a fundamental number of 50. Blarina brevicauda in Nebraska and Pennsylvania has a diploid number of 49 or 50 and a fundamental number of 48. Blarina carolinensis in Nebraska and Kansas has a diploid number of 52 and a fundamental number of 62. The X-chromosome in all 3 species is a large metacentric chromosome. The Y-chromosome is a small acrocentric in Blarina, whereas in Cryptotis it is a small subtelocentric.

]]> Hugh H. Genoways et al. CHARACTERIZATION OF A CONTACT ZONE BETWEEN TWO SUBSPECIES OF THE BIG BROWN BAT (<i>EPTESICUS FUSCUS</i>) IN NEBRASKA http://digitalcommons.unl.edu/museummammalogy/146 http://digitalcommons.unl.edu/museummammalogy/146 Tue, 14 Feb 2012 07:02:09 PST Two subspecies of the big brown bat (Eptesicus fuscus) are reported to occur in Nebraska. The eastern race, E. f. fuscus, is reportedly bigger and darker than its western counterpart E. f. pallidus. Where these 2 subspecies come in contact is the subject of debate. We used external, cranial, and colorimetric data to investigate geographic variation among populations of E. fuscus in Nebraska to determine the location of the zone of contact between E. f. fuscus and E. f. pallidus. We discovered significant variation in external, cranial, and colorimetric data, suggesting that E. fuscus is represented by 2 subspecies in Nebraska. Our results showed that E. f. pallidus is smaller, possesses lighter pelage, and is restricted to the northern and western parts of Nebraska, whereas E. f. fuscus is larger, possesses darker pelage, and occurs in southern and southeastern parts of the state. Populations located between these regions represent intergrades of the 2 subspecies. We suggest that the subspecific boundary represents a broad zone of integration running in a northeast to southwest direction and may reflect the position of temperature and precipitation clines.

]]> Justin D. Hoffman et al. Annotated Checklist of Mammals of the Yucatan Peninsula, Mexico. III. Marsupialia, Insectivora, Primates, Edentata, Lagomorpha http://digitalcommons.unl.edu/museummammalogy/145 http://digitalcommons.unl.edu/museummammalogy/145 Thu, 03 Nov 2011 14:30:23 PDT This is the third in a series of papers detailing the distribution of mammalian species occurring on the Yucatan Peninsula of Mexico. The present paper deals with 12 native species belonging to the following orders: Marsupialia, six; Insectivora, one; Primates, two; Edentata, two; Lagomorpha, one. None of these species is endemic to the peninsula, although it constitutes the major part of the geographic range of Alouatta pigra. Endemic subspecies include Didelphis virginiana yucatanensis, Marmosa mexicana mayensis, and Sylvilagus floridanus yucatanicus.

]]> J. Knox Jones et al. A New Species of <i>Oryzomys</i> (Rodentia: Muridae) from an Isolated Pocket of Cerrado in Eastern Bolivia http://digitalcommons.unl.edu/museummammalogy/144 http://digitalcommons.unl.edu/museummammalogy/144 Wed, 26 Oct 2011 12:15:55 PDT Reliable characterization of a species is an essential step toward eventual reconstruction of phylogenetic alliances among related taxa (Musser et al. 1998). Although characterization of species within the genus Oryzomys has met with some confusion in the past, significant work has taken place to help better define specific limits within this group (Musser et al. 1998; Bonvicino and Moreira 2001; Langguth and Bonvicino 2002).

In spite of several recent surveys performed in the eastern Bolivian Panhandle (Emmons 1993; Taber et al. 1997; Brooks et al. 2002), our knowledge of the mammalian fauna in this region is still incomplete, and further studies are warranted. For example, of 1,259 collecting localities in Bolivia analyzed by Anderson (1997), less than two percent are from the eastern panhandle of Santa Cruz Department. Thus, this region constitutes a priority for mammalian exploration and conservation.

In mid-April 1999, during an expedition to the eastern Bolivian panhandle (Brooks et al. 2002), we collected a single specimen of the genus Oryzomys that could not be assigned to any known species previously reported for the region in former studies (e.g., Anderson 1993, 1997). Extensive morphological comparisons with deposited voucher specimens revealed that this specimen may represent an undescribed species most closely related to the O. subflavus group (Guy Musser, pers. comm.). To confirm this taxonomic hypothesis, molecular analyses using a portion of the mitochondrial cytochrome-b gene were perfonned to establish phylogenetic relationships. Molecular data supported our conclusion that this specimen represents a new taxon within the genus. In this study, we describe a new form of Oryzomys from the Department of Santa Cruz, Bolivia.

]]> Daniel M. Brooks et al. Bats of Barbuda, Northern Lesser Antilles http://digitalcommons.unl.edu/museummammalogy/143 http://digitalcommons.unl.edu/museummammalogy/143 Mon, 24 Oct 2011 11:22:09 PDT Five species of bats are known to occur on the Lesser Antillean island of Barbuda—Noctilio leporinus, Monophyllus plethodon, Brachyphylla cavernarum, Tadarida brasiliensis, and Molossus molossus. During the present study, two additional species of bats—Artibeus jamaicensis and Natalus stramineus—were added to the chiropteran fauna of the island. Although the ecological diversity of Barbuda is limited, this bat fauna matches those of islands in the region such as Antigua, Nevis, and St. Kitts. It is proposed that this biodiversity of bats is maintained because of the geology of Barbuda provides ample roosting sites and access to freshwater in caves, bluff faces, and sinkholes. The conservation of the chiropteran fauna of Barbuda, therefore, depends on the protection of these geological resources.

]]> Scott C. Pedersen et al. Systematic Revision of the Northern Short-tailed Shrew, <i>Blarina brevicauda</i> (Say) http://digitalcommons.unl.edu/museummammalogy/142 http://digitalcommons.unl.edu/museummammalogy/142 Wed, 31 Aug 2011 11:17:02 PDT Short-tailed shrews, genus Blarina, are common inhabitants of a variety of terrestrial habitats in most of eastern North America. Of the 4 species currently recognized, the northern short-tailed shrew, Blarina brevicauda (Say, 1823), is the most widely distributed, occurring from southern Canada southward to the central Great Plains and the Appalachian Mountains into Georgia and Alabama and along the East Coast as far south as southeastern North Carolina. It has been more than 65 years since geographic variation within this species has been studied. Accordingly, the objectives of this study were to examine geographic variation in Blarina brevicauda and to revise its intraspecific taxonomy as needed.

A total of 12,390 Holocene specimens of Blarina brevicauda from throughout the geographic range of the species and the fossil material of Blarina fossilis, B. ozarkensis, and B. simplicidens were examined during the course of this study. Nine cranial and mandibular measurements were taken from 2,736 Holocene specimens, which were grouped into 114 operational taxonomic units (OTUs) for statistical analysis. We used a single classification ANOVA to test for significant differences among means of OTUs and a principal component analysis (PCA) to extract eigenvectors and generate a 2-dimensional plot of OTUs.

Our analysis demonstrates that B. brevicauda consists of 7 well-defined subspecies. Two subspecies, the large-bodied B. b. brevicauda and the medium-sized B. b. talpoides, occupy almost the entire geographic range of the species, with restricted gene flow between these 2 subspecies where their geographic ranges abut in the vicinity of the Mississippi River and its valley. The other 5 subspecies occupy small to modest geographic ranges at the periphery of the range of the species and in isolated geographic areas—an undescribed subspecies on the Cumberland Plateau in Tennessee and adjacent Kentucky, B. b. knoxjonesi along the southeastern coast of North Carolina, another undescribed subspecies on the southern two-thirds of the Delmarva Peninsula, B. b. aloga on Martha’s Vineyard and Nantucket Island, and a third undescribed subspecies in the Kaw River Valley in northeastern Kansas. In each of these geographic areas, gene flow has been stopped or greatly restricted. We have chosen to recognize these 7 subspecies because we believe that each has begun to follow its own evolutionary path. These taxa are arranged in a geographic configuration that fits the pattern termed centrifugal speciation, or the development of small isolated peripheral and sometimes relictual populations as the parent taxon undergoes normal population expansion and contraction cycles. The fact that at least 3 of these peripheral populations are now partially in contact with the parental populations and have not been swamped out genetically indicates to us that they are adapting to their local conditions and are able to maintain their genetic identities. Our morphological data and mitochondrial DNA analyses by other workers indicate that these peripheral subspecies, with the possible exception of the 1 along the Kaw River valley, are derived from B. b. talpoides. These data also indicate that B. b. brevicauda and B. b. talpoides are semi-species.

[87 pages]

]]> Wm. David Webster et al. Identification and characterization of the contact zone between short-tailed shrews (<i>Blarina</i>) in Iowa and Missouri http://digitalcommons.unl.edu/museummammalogy/141 http://digitalcommons.unl.edu/museummammalogy/141 Wed, 31 Aug 2011 11:02:45 PDT Short-tailed shrews (genus Blarina Gray, 1838) are characterized by divergent karyotypes and are genetically distinct. Blarina species are similar morphologically but, in most cases, can be distinguished morphometrically. Blarina distributions tend to be parapatric along well-defined contact zones; however, it has been suggested that the northern short-tailed shrew (Blarina brevicauda (Say, 1823)) and Elliot’s short-tailed shrew (Blarina hylophaga Elliot, 1899) occur sympatrically in Iowa and Missouri. To evaluate this possibility, 179 specimens were collected in southwestern Iowa and northwestern Missouri. Karyotypes and total length were used for field identification, and amplified fragment length polymorphism (AFLP) analysis was used to verify field identifications and to investigate the extent of hybridization. One hundred seventy-eight of 179 specimens were identified to species. The one exception had a karyotype of B. brevicauda (2n = 50, FN = 48); however, AFLP analysis indicated that this individual was likely an F1 hybrid. No backcrosses were detected, so it appears that introgression is minimal. The putative hybrid was trapped at a locality with B. brevicauda just north of a locality having only B. hylophaga. No locality contained both species. Therefore, these species are not broadly sympatric as has been suggested, but rather exhibit a distribution similar to the pattern of parapatry seen in most of the contact zones of Blarina.

Les musaraignes à queue courte (du genre Blarina Gray, 1838) se caractérisent par des caryotypes divergents et sont génétiquement distinctes. Les espèces de Blarina sont semblables morphologiquement, mais dans la plupart des cas, la morphométrie permet de les distinguer. Les répartitions des Blarina ont tendance à être parapatriques le long de zones de contact bien définies; on croit néanmoins que la grande musaraigne à queue courte (Blarina brevicauda (Say, 1823)) et la musaraigne à queue courte d’Elliot (Blarina hylophaga Elliot, 1899) se retrouvent en sympatrie en Iowa et au Missouri. Afin de vérifier cette possibilité, nous avons récolté 179 spécimens dans le sud-ouest de l’Iowa et le nord-ouest du Missouri. Les caryotypes et la longueur totale nous ont servi pour les identifications de terrain et une analyse du polymorphisme des longueurs des segments amplifiés (AFLP) a permis de confirmer les identifications de terrain et de déterminer l’importance de l’hybridation. Des 179 spécimens, 178 ont été identifiés à l’espèce. La seule exception avait un caryotype de B. brevicauda (2n = 50, FN = 48); cependant l’analyse de ALFP indique que cet individu est vraisemblablement un hybride de F1. Comme il n’y a aucune indication de rétrocroisement, l’introgression semble minimale. L’hybride putatif a été piégé dans une localité contenant B. brevicauda située juste au nord d’une localité où vit seulement B. hylophaga. Aucune localité ne contient les deux espèces. Les deux espèces ne possèdent donc pas une importante zone de sympatrie, comme on le croyait; ils ont plutôt une répartition parapatrique du type observé dans la plupart des zones de contact de Blarina.

]]> Cody W. Thompson et al.