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Full-Text Articles in Biodiversity

Distribution And Natural History Of Amphibians And Reptiles In Western Nebraska With Ecological Notes On The Herpetiles Of Arapaho Prairie, Royce E. Ballinger, John D. Lynch, Patrick H. Cole Sep 1979

Distribution And Natural History Of Amphibians And Reptiles In Western Nebraska With Ecological Notes On The Herpetiles Of Arapaho Prairie, Royce E. Ballinger, John D. Lynch, Patrick H. Cole

Papers in Herpetology

Introduction: The distribution and natural history of amphibians and reptiles have been little studied in the northern states of the great plains. Relative to other vertebrate groups, the herpetofauna of grasslands is depauperate particularly at higher latitudes where temperature becomes a limiting factor to poikilotherms. Nevertheless, certain species of amphibians and reptiles are common in specific habitats and thus form a conspicuous component of the prairie fauna. The purposes of the present study were to document the distributions of herpetiles in a specified region of western Nebraska and to describe general aspects of their natural history. We hope such information …


The Prairie Naturalist Volume 11, Number 3. September 1979 Sep 1979

The Prairie Naturalist Volume 11, Number 3. September 1979

The Prairie Naturalist

DISTRIBUTION AND NATURAL HISTORY OF AMPHIBIANS AND REPTILES IN WESTERN NEBRASKA WITH ECOLOGICAL NOTES ON THE HERPETILES OF ARAPAHO PRAIRIE ▪ R. E. Ballinger, J. D. Lynch and P. H. Cole

AVIAN MORTALITY FROM A SEVERE HAIL STORM ▪ J. L. Piehl

EFFECTS OF A SUMMER STORM ON BIRD POPULATIONS ▪ D. H. Johnson

SEXING AND AGING CRITERIA FOR THE WHITE PELICAN ▪ G. R. Lingle and N. F. Sloan

CANVASBACK DUCK RECOVERS FROM COMPOUND LUXATION TO WING ▪ H. A. Doty

SECOND NORTH DAKOTA RECORD OF LOUISIANA WATERTHRUSH ▪ C. A. Faanes

FIRST NESTING RECORD OF A LOUISIANA HERON …


The Prairie Naturalist Volume 11 , Number 2. June 1979 Jun 1979

The Prairie Naturalist Volume 11 , Number 2. June 1979

The Prairie Naturalist

SPECIES WITH EXTRA FLORAL NECTARIES IN A TEMPERATE FLORA (NEBRASKA) ▪ Kathleen H. Keeler

PLANTS OF MOUNT GOLIATH RESEARCH NATURAL AREA ▪ Jeanette Hartman and Rod Mitchell

STATUS OF THE STURGEON CHUB (HYBOPSIS GELIDA) AND SICKLEFIN CHUB (HYBOPSIS MEEKI) IN NORTH DAKOTA ▪ Robert C. Reigh and Dean S. Elsen

OBSERVATIONS ON COYOTE BIOLOGY IN NORTH-CENTRAL MISSOURI ▪ Fred B. Samson and Bill D. Hill

DESTRUCTION TO NESTING BIRDS ON A MARSH BAY BY A SINGLE STORM ▪ Martin K. McNicholl

BOOK REVIEWS

Presentations on Predators ▪ Staff

Migratory Game Birds ▪ Ronald A. Ryder

Wolf …


Distribution Of Plants With Extrafloral Nectaries And Ants At Two Elevations In Jamaica, Kathleen H. Keeler Jun 1979

Distribution Of Plants With Extrafloral Nectaries And Ants At Two Elevations In Jamaica, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

Frequencies of plants with extrafloral nectaries were determined for two elevations in Jamaica. Extrafloral nectaries were found on 0.28 of the plants at sea level (Happy Grove, Portland) and 0.00 of the plants at 1310 m (Whitfield Hall, St. Thomas). Ant abundance, as indicated by discovery of and recruitment to baits, was greater at the lower elevation site. However, despite the apparent absence of plants with extrafloral nectaries, there were abundant ants at 1310 m.


A Study Of Nongeographic Variation In Tatera Leucogaster (Mammalia: Rodentia) From Botswana, Pierre Swanepoel, Duane A. Schlitter, Hugh H. Genoways Mar 1979

A Study Of Nongeographic Variation In Tatera Leucogaster (Mammalia: Rodentia) From Botswana, Pierre Swanepoel, Duane A. Schlitter, Hugh H. Genoways

University of Nebraska State Museum: Mammalogy Papers

Specimens of Tatera leucogaster from six localities in Botswana were tested for variation with age, secondary sexual variation, and individual variation. Of the six age classes recognized, categories I, II, and III each formed their own group, whereas cat egories IV, V, and VI were not separable on a morphometric basis and were considered to be adults. Significant secondary sexual variation was found only in depth of braincase in which females were larger. The only character exhibiting unusually high individual variation was length of posterior palatal foramen. All other characters exhibited individual variation within acceptable limits.


The Prairie Naturalist Vol. 11, No. 1. March, 1979 Mar 1979

The Prairie Naturalist Vol. 11, No. 1. March, 1979

The Prairie Naturalist

ORIN ALVA STEVENS, A PRAIRIE NATURALIST ▪ G. Monson

FIRST RECORD OF LONG-TAILED JAEGER FOR NORTH DAKOTA ▪ T. Gatz and D. Treasure

NEW RECORDS OF THE DWARF SHREW (SOREX NANUS) IN SOUTH DAKOTA ▪ R. J. Cinq-Mars, R. S. Hoffmann and J. K. Jones, Jr.

THE ETHYLENE FROM BURNING LIGNITE AS A PROBABLE CAUSE OF COLUMNARITY IN NORTH DAKOTA JUNIPERS ▪ J. M. Murphy and D. J. Holden

CAMOUFLAGED COYOTE DEN ENTRANCES ▪ D. P. Althoff

CHRISTMAS BIRD COUNTS FOR NORTH DAKOTA - 1978 ▪ R.N. Randall

NOTES

An Upland Nest of the Virginia Rail in North …


Species With Extrafloral Nectaries In A Temperate Flora (Nebraska), Kathleen H. Keeler Mar 1979

Species With Extrafloral Nectaries In A Temperate Flora (Nebraska), Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

Extrafloral nectaries (EFNs) are glands on a plant, not involved in pollination, that produce solutions containing sugars (and other compounds). Long noted by morphologists, EFNs have recently been observed to be part of ant-plant mutualisms. The function of EFNs appears to be to attract aggressive insects, especially ants, which by disturbing or preying upon herbivores, reduce damage to the plant (Janzen, 1966a,b; Elias and Gelband, 1975; Keeler, 1975, 1977; Bentley, 1976, 1977a,b; Schemske, 1978; Tilman, 1978; Inouye and Taylor, 1979; Pickett ad Clark, 1979). Furthermore, they constitute an unusual plant defense against herbivores: at EFNs plants employ ants as a …


Wolf Howling And Its Role In Territory Maintenance, Fred H. Harrington, L. David Mech Jan 1979

Wolf Howling And Its Role In Territory Maintenance, Fred H. Harrington, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

The wolf (Canis lupus) is a wide-ranging social carnivore with a complex spatial organization (MECH, 1972; 1973). The precise manner in which this organization is maintained is unknown, but territory advertisement using olfactory and acoustic modes seems to be involved.

The acoustic mode includes primarily howling. Within a wolf pack, howling may be useful to reassemble separated members (MECH, 1966; THEBERGE & FALLS, 1967), and may communicate information on individual identity, location, and other behavioral and environmental contingencies (THEBERGE & FALLS, 1967). Between packs, however, howling may serve to advertise territory, communicating the locations of packs and thus …


Niobrara-Missouri River Fishery Investigations, Larry W. Hesse, Gene Zeurlein, Roger Vancil, Leonard Koziol, Brad Newcomb, Leigh Ann Retelsdorf Jan 1979

Niobrara-Missouri River Fishery Investigations, Larry W. Hesse, Gene Zeurlein, Roger Vancil, Leonard Koziol, Brad Newcomb, Leigh Ann Retelsdorf

Nebraska Game and Parks Commission: Publications

The Niobrara River heads in the table lands of eastern Wyoming and flows 786 kilometers (km) eastward across Nebraska joining the Missouri River near the town of Niobrara, Nebraska. The Niobrara is the largest Missouri River tributary between the last two mainstem impoundments (Lake Francis Case and Lewis and Clark Lake). Fish movement up the Niobrara is prevented by Nebraska Public Power District's (NPPD's) Spencer Hydroelectric Dam, 63.3 km upstream from the river mouth. The lower reach of the river is turbid and carries a considerable load of sand, silt, and organic debris into the Missouri River. The mean annual …


Nebraska Rainbow Trout, Nebraska Game And Parks, G. Zeurlein, L. Hesse, J. Seeb, L. Wishard Jan 1979

Nebraska Rainbow Trout, Nebraska Game And Parks, G. Zeurlein, L. Hesse, J. Seeb, L. Wishard

Nebraska Game and Parks Commission: Publications

Chapter 1 Lethal and Preferred Temperatures of Lake McConaughy Rainbow Trout Versus Domestic Strain Rainbow Trout By R. Vancil, G. Zuerlein and L. Hesse

Chapter 2 A Nitrifying Filter-Cooling Condenser System for Total Water Re-use in Cold-Water Fish Holding or Rearing Applications By L. Hesse, G. Zuerlein and R. Vancil

Chapter 3 Biochemical Genetic Analysis of Two Strains of Nebraska Rainbow Trout By J. Seeb and L. Wishard

The self-sustaining rainbow trout population living in Lake Mcconaughy and the North Platte River tributaries is unique to the Great Plains region. The population spends most of its adult life in the …


Specimen Catalog & Field Notes, Elizabeth Boyd Jan 1979

Specimen Catalog & Field Notes, Elizabeth Boyd

Division of Mammals - Field Notes and Catalogs

No abstract provided.


Revision Of The Antillean Bats Of The Genus Brachyphylla (Mammalia: Phyllostomatidae), Pierre Swanepoel, Hugh H. Genoways Dec 1978

Revision Of The Antillean Bats Of The Genus Brachyphylla (Mammalia: Phyllostomatidae), Pierre Swanepoel, Hugh H. Genoways

University of Nebraska State Museum: Mammalogy Papers

Nongeographic and geographic variation have been analyzed in the genus Brachyphylla. which belongs to the Antillean endemic subfamily Phyllonycterinae of the family Phylloslomatidae. Males were found to be generally larger than females: therefore, the sexes were analyzed separately for geographic variation. External measurements except length of forearm were found to displaya high degree of individual variation. They were not used in subsequent analyses. Of cranial measurements, greatest length of skull and condylobasal length showed the least individual variation, whereas palatal length, postorbital breadth (in samples from west of the Mona Passage only), and rostral width at canines showed relatively …


The Prairie Naturalist Volume 10, Number 4. December 1978 Dec 1978

The Prairie Naturalist Volume 10, Number 4. December 1978

The Prairie Naturalist

THE ORNITHOGEOGRAPHY OF THE GREAT PLAINS STATES ▪ Paul A. Johnsgard

CAPTURE OF GRAY PARTRIDGE BY FALCONRY IN NORTH DAKOTA ▪ John W. Schulz

INCUBATION RHYTHMS AND EGG TEMPERATURES OF AN AMERICAN GREEN-WINGED TEAL AND A RENESTING PINTAIL ▪ Alan D. Afton

TEMPORAL PATTERNS OF SPRING MIGRATION OF YELLOW-HEADED BLACKBIRDS IN NORTH DAKOTA ▪ Richard D. Crawford

CHECKLIST OF NORTH DAKOTA MAMMALS: COMMENTS ON STATUS AND DISTRIBUTION OF SPECIES ▪ Robert W. Seabloom

NOTE

First Nesting Record of Cattle Egret and Little Blue Heron in North Dakota ▪ Lloyd A. Jones

BOOK REVIEWS

Geese of the World ▪ Carl E. …


The Ornithogeography Of The Great Plains States, Paul A. Johnsgard Dec 1978

The Ornithogeography Of The Great Plains States, Paul A. Johnsgard

Paul Johnsgard Collection

It has long been recognized that the Great Plains represent a major transition zone in the distribution patterns of North American birds; field guides traditionally have treated the 100° W.longitude meridian as a convenient dividing line between eastern and western faunas. Furthermore, this line rather neatly bisects the political subdivisions of the Great Plains, namely the "plains states" extending from North Dakota southward through South Dakota, Nebraska, Oklahoma, and Texas. Of these, Texas is the least typical, its climate and fauna is strongly influenced by the Gulf Coast on the east and the Chihuahuan desert on the west. As a …


Review Of The Desert Pocket Gopher, Geomys Arenarius (Mammalia: Rodentia), Stephen L. Williams, Hugh H. Genoways Dec 1978

Review Of The Desert Pocket Gopher, Geomys Arenarius (Mammalia: Rodentia), Stephen L. Williams, Hugh H. Genoways

University of Nebraska State Museum: Mammalogy Papers

The desert pocket gopher (Geomys arenarius), which occupies a restricted geographic range in Texas, New Mexico, and Chihuahua, was examined for morphological variation. Univariate and multivariate analyses were used to determine age, sexual, individual, and geographic variation. Significant differences were found among different age classes and between sexes. Males displayed higher individual variation than females and external measurements were more variable than cranial measurements. Two subspecies--G. a. arenarius and G. a. brevirostris--were recognized after analyses of geographic variation.


Bats Are Beautiful, Hugh H. Genoways, Robert J. Baker Oct 1978

Bats Are Beautiful, Hugh H. Genoways, Robert J. Baker

University of Nebraska State Museum: Mammalogy Papers

The thought that "Bats are Beautiful" may bring a smile to your face as you think of these ugly little creatures hanging from the ceilings of haunted houses and flying around deserted bell towers at midnight. You may also remember old wives tales such as "all bats have rabies" or "bats try to fly into women's hair." None of these things is completely true, and some of the tales have no basis in fact whatsoever.

Actually, the 875 species of bats form a unique Order of mammals (those animals possessing hair at least somewhere on their bodies), since they are …


Notes On Distribution Of Three Species Of Mammals In South Dakota, J. Knox Jones Jr., Jerry R. Choate, Robert B. Wilhelm Sep 1978

Notes On Distribution Of Three Species Of Mammals In South Dakota, J. Knox Jones Jr., Jerry R. Choate, Robert B. Wilhelm

University of Nebraska State Museum: Mammalogy Papers

No definitive account of the mammals of South Dakota has been published and, therefore, the distribution of species occurring in that state is relatively poorly documented save for several geographically restricted faunal studies (Andersen and Jones 1971, on Harding County, Findley 1956, on Oay County, and Turner 1974, on the Black Hills, for example). Our own work in South Dakota began almost two decades ago, but in recent years has focued primarily on the unique environmental area in southern Bennett County. Three species of mammals for which we have important unpublished distributional records from the state are the eastern mole, …


A Mid-Continent Irruption Of Canada Lynx, 1962-63, Harvey L. Gunderson Sep 1978

A Mid-Continent Irruption Of Canada Lynx, 1962-63, Harvey L. Gunderson

University of Nebraska State Museum: Mammalogy Papers

There was a mid-continent irruption of the Canada lynx (Felis lynx) population and subsequent extensive movement into non-lynx habitats during the years 1962-1963. Lynx were found in the prairie provinces of Canada and the prairie areas of Minnesota, and North and South Dakota. They were also found in urban areas such as Minneapolis and St. Paul, Minnesota: Winnipeg, Manitoba: and Calgary, Saskatchewan, Canada. Causes for the irruption remain unknown but speculations include primarily a change in snowshoe hare population, disease, extensive forest fires and extensive spraying. Unusual behavior seemed to be most often reflected by a lack of …


The Prairie Naturalist Vol. 10, No. 3. September 1978 Sep 1978

The Prairie Naturalist Vol. 10, No. 3. September 1978

The Prairie Naturalist

NOTES ON DISTRIBUTION OF THREE SPECIES OF MAMMALS IN SOUTH DAKOTA ▪ J. K. Jones, Jr., J. R. Choate and R. B. Wilhelm

A MID-CONTINENT IRRUPTION OF CANADA LYNX, 1962-63 ▪ H. L. Gunderson

CHECKLIST OF NORTH DAKOTA MAMMALS (REVISED) ▪ J. M. Wiebe and J. F. Cassel

DECLINE OF YEAR-CLASS STRENGTH OF BUFFALO FISHES IN LAKE SAKAKAWEA, NORTH DAKOTA ▪ D. W. Willis and J. B. Owen

NOTE

Pileated Woodpecker Eating Russian Olive Fruits ▪ R. S. McVoy

BOOK REVIEWS

Birds of the Prairie Provinces ▪ W. J. Maher

Wildlife of the Prairies ▪ C. R. Grondahl

Distribution Patterns …


Proposed Critical Habitat For The Whooping Crane Aug 1978

Proposed Critical Habitat For The Whooping Crane

Endangered Species Bulletin

The Service proposes eight additional areas as critical habitat in Kansas, Montana, Nebraska. North Dakota, and South Dakota for the endangered whooping crane (Grus americana) to those areas already determined to be critical habitat as published in the FEDERAL REGISTER of May 15, 1978 (43 FR 20938). If finalized, this rule would provide Federal protection of these areas under section 7 of the Endangered Species Act of 1973 and will further assure the conservation of the whooping crane.


The Prairie Naturalist Vol. 10, No. 2. June 1978 Jun 1978

The Prairie Naturalist Vol. 10, No. 2. June 1978

The Prairie Naturalist

ANALYSIS OF THE FLEHMEN DISPLAY IN AMERICAN BISON (BISON BISON) ▪ B. R. Mahan, M. P. Munger and H. L. Gunderson

AVIAN MORTALITY CAUSED BY A SEPTEMBER WIND AND. HAIL STORM ▪ K. F. Higgins and M. A. Johnson

DISTRIBUTION OF TWO SPECIES OF LONG-EARED BATS OF THE GENUS MYOTIS ON THE NORTHERN GREAT PLAINS ▪ J. K. Jones, Jr. and J. R. Choate

ALFALFA AND THE OCCURRENCE OF FISSURES ON THE NORTH DAKOTA PRAIRIES ▪ J. P. Bluemle, A. E Kehew, E. A. Brostuen and K. L. Harris

NOTES

An Observation of Badger Predation on Richardson Ground Squirrels ▪ …


Distribution Of Two Species Of Long-Eared Bats Of The Genus Myotis On The Northern Great Plains, J. Knox Jones Jr., Jerry R. Choate Jun 1978

Distribution Of Two Species Of Long-Eared Bats Of The Genus Myotis On The Northern Great Plains, J. Knox Jones Jr., Jerry R. Choate

University of Nebraska State Museum: Mammalogy Papers

Two long-eared species of the cosmopolitan bat genus Myotis, the long-eared myotis (Myotis evotis) and the fringe-tailed myotis (Myotis thysanodes), have been known for many years from the Northern Great Plains. Material acquired in the last decade or so, however, reveals a somewhat different distributional pattern for the two species than had been supposed on the basis of specimens obtained earlier, some of which have been misidentified in the published literature.


Bats Of Guadeloupe, Robert J. Baker, Hugh H. Genoways, John C. Patton May 1978

Bats Of Guadeloupe, Robert J. Baker, Hugh H. Genoways, John C. Patton

University of Nebraska State Museum: Mammalogy Papers

The bat fauna of the Lesser Antillean chain is of considerable interest because it is composed of a depauperate extension of the South American fauna, species that have a widespread distribution in the Antilles, and a few species that are endemic to the Lesser Antilles (Baker and Genoways, 1978). Relative to bat speciation and diversity, Guadeloupe is probably the most important island of the Antillean chain.

This report is concerned with the natural history and systematics of the 11 chiropteran species known from Guadeloupe, three of which are endemic. Comments concerning systematic relationships are based on specimens that we collected …


Determination Of Critical Habitat For The Whooping Crane May 1978

Determination Of Critical Habitat For The Whooping Crane

Endangered Species Bulletin

The Service determines Critical Habitat for the whooping crane (Grus americana). an Endangered species, in the States of Colorado, Idaho, Kansas, Nebraska, New Mexico, Oklahoma, and Texas. This rule provides Federal protection of these areas under Section 7 of the Endangered Species Act of 1973 and is taken to assure the conservation of the whooping crane.


Bats From Southern Haiti, David Klingener, Hugh H. Genoways, Robert J. Baker Mar 1978

Bats From Southern Haiti, David Klingener, Hugh H. Genoways, Robert J. Baker

University of Nebraska State Museum: Mammalogy Papers

A collection of 450 specimens of bats from the Departement du Sud, Haiti, is described. Fifteen of the 17 species previously recorded from Hispaniola are represented, and Noctilio leporinus is reported from Haiti for the first time. Reproductive information for the months of January, May, June, August, and December is presented. Macrotus waterhousii is seasonally monoestrous, as on the mainland. The two species of stenodennines, Artibeus jamaicensis and Phyllops hailiensis, do not show bimodal seasonal polyestry as do stenodermines in Central America. Monophyllus redmani and the phyllonycterines may be seasonally monoestrous. Differences in reproductive biology between Haitian bats and …


The Prairie Naturalist Vol. 10. No. 1 March. 1978 Mar 1978

The Prairie Naturalist Vol. 10. No. 1 March. 1978

The Prairie Naturalist

KEY TO THE SKULLS OF NORTH DAKOTA MAMMALS ▪ J. M. Wiebe

RESPONSES OF PRAIRIE GROUSE TO AVIAN AND MAMMALIAN VISITORS ON DISPLAY GROUNDS IN NORTHWESTERN MINNESOTA ▪ D. W. Sparling, Jr. and W. D. Svedarsky

FIRST NESTING RECORD OF THE CASPIAN TERN IN NORTH DAKOTA ▪ J. F. Herman, R. A. Schmidt and K. J. Wilson

MARSH HAWK PREDATION ON BLACK TERN AND PECTORAL SANDPIPER ▪ G. D. Maxson

CHRISTMAS BIRD COUNTS FOR NORTH DAKOTA—1977 ▪ R. N. Randall

BOOK REVIEW

Audubon Society "Field Guides" ▪ D. L. Kubischta


Relating Wolf Scat Content To Prey Consumed, Theodore J. Floyd, L. David Mech, Peter A. Jordan Jan 1978

Relating Wolf Scat Content To Prey Consumed, Theodore J. Floyd, L. David Mech, Peter A. Jordan

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

In 9 trials, captive wolves (Canis lupus) were fed prey varying in size from snowshoe (Lepus americanus) to adult deer (Odocoileus virginianus), and the resulting scats were counted. collectible scats were distinguished from liquid, noncollectible stools. In collectible scats, the small prey occurred in greater proportion relative to the prey's weight, and in lesser proportion to the prey's numbers, than did the remains of larger prey. A regression equation with an excellent the data (r2 = 0.97) was derived to estimate the weight of prey eaten per collectible scat for With this information …


Zoogeography Of Antillean Bats, Robert J. Baker, Hugh H. Genoways Jan 1978

Zoogeography Of Antillean Bats, Robert J. Baker, Hugh H. Genoways

University of Nebraska State Museum: Mammalogy Papers

Analysis of the bat fauna of the Antillean Islands suggest that the most probable source of invasion of the islands by bats is by overwater dispersal. The bat fauna of ·the Greater Antilles is unique, a percentage of endemism on each island being over 50 percent except for the Virgin Islands which has 33 percent endemics.

The richest bat fauna in the Antilles is on Cuba (32 species) followed by Jamaica (23 species) then Hispaniola (17 species) and Puerto Rico (16 species). The number of species found on Cuba is probably the result of the island's proximity to Central and …


Ten-Year Index To The Prairie Naturalist Vols. 1-10 (1968-1978), Virginia Steinhaus Jan 1978

Ten-Year Index To The Prairie Naturalist Vols. 1-10 (1968-1978), Virginia Steinhaus

The Prairie Naturalist

11 pages

From: ACANTHOMYOPS CLAVIGER,

to: Zink, R.M.,


Morphometric Variation In The Tropical Pocket Gopher (Geomys Tropicalis), Stephen L. Williams, Hugh H. Genoways Nov 1977

Morphometric Variation In The Tropical Pocket Gopher (Geomys Tropicalis), Stephen L. Williams, Hugh H. Genoways

University of Nebraska State Museum: Mammalogy Papers

The tropical pocket gopher (Geomys tropicalis). which exhibits no chromosomal or genic variation, was examined for variability at the morphometrical level. Univariate and multivariate analyses were used to determine age, sexual, and geographical variation. Significant differences were found between different age classes and between sexes. The amount of individual variation was comparable with other rodents and did not exhibit the reduced variation expressed at the chromosomal and genic levels, G. tropicalis is considered to be a monotypic species.