Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network™

Open Access. Powered by Scholars. Published by Universities.®

Ecology and Evolutionary Biology

Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 11821 - 11850 of 12812

Full-Text Articles in Entire DC Network

Extension's Perspective Of Federal, State And Private Animal Damage Control Programs, Gary J. San Julian Sep 1987

Extension's Perspective Of Federal, State And Private Animal Damage Control Programs, Gary J. San Julian

Wildlife Damage Management Conference

Extension personnel are in a unique position to observe and to be involved in animal damage control (ADC) programs at the federal, state and private levels. In order to offer educational programs, we must interpret regulations and policies to provide a workable interface between ourselves, other agencies and the public. This is not an easy task in such a sensitive and emotional area.


Report Of The Rock Lobster Industry Advisory Committee To The Hon. Minister For Fisheries., Rock Lobster Industry Advisory Committee Sep 1987

Report Of The Rock Lobster Industry Advisory Committee To The Hon. Minister For Fisheries., Rock Lobster Industry Advisory Committee

Fisheries Management Papers

The Committee recognises that the exploitation rate on the rock lobster stocks is very high and that this factor is a major importance in formulating the advice on management measures. However, the Committee also recognises the high level of capital investment in the industry and that any recommendation which leads to a significant change in the management rules is likely to have a far reaching effect on many of the participants. Accordingly, the Committee endeavours to reduce to a minimum the year to year changes in the management rules. When changes are required the Committee places considerable weight on matters …


Benthic Invertebrates And Crayfish Of Lake Mead, Susan K. Peck, William L. Pratt, James E. Pollard, Larry J. Paulson, Donald H. Baepler Sep 1987

Benthic Invertebrates And Crayfish Of Lake Mead, Susan K. Peck, William L. Pratt, James E. Pollard, Larry J. Paulson, Donald H. Baepler

Publications (WR)

The objectives of this study were to:

1. Establish baseline densities of benthic invertebrates and relative abundance of crayfish in Lake Mead.

2. Evaluate the distributions of benthic organisms and crayfish in relation to existing habitat conditions and 1imnological characteristics of Lake Mead.

3. Measure seasonal changes in abundances of benthic organisms and crayfish in Lake Mead.

4. Compare observations of Procambarus clarkii life history in Lake Mead to reports from other aquatic systems.

5. Evaluate the importance of benthic organisms and crayfish as food sources for game fish in Lake Mead.


Further Options For Management Of The Shark Bay Snapper Fishery : Discussion Paper., P. Millington Jul 1987

Further Options For Management Of The Shark Bay Snapper Fishery : Discussion Paper., P. Millington

Fisheries Management Papers

A limited entry fishing regime for snapper was introduced in Shark Bay in order to constrain growth in fishing effort. Additional measures were introduced to reduce the number of vessels in the fishery, control areas fished and limit permitted fishing gear, with the ultimate objective of reducing catches from traditional fishing areas to long term sustainable levels.


A Taxonomic Survey Of The Family Gyrinidae (Coleoptera) Of The State Of Virginia, Jerrold R. Harris Jul 1987

A Taxonomic Survey Of The Family Gyrinidae (Coleoptera) Of The State Of Virginia, Jerrold R. Harris

Biological Sciences Theses & Dissertations

The aquatic insect fanua of Virginia is not very well known. This is especially true of the order Coleoptera. There are few taxonomic studies on the families of Coleoptera found within the state, and one of the least known is the family Gyrinidae. It is the intent of this study to determine what species of Gyrinidae are found within the state and where they are found. Collections of the beetles were made throughout the state from March to December.

Twenty-one species of Gyrinidae were identified in Virginia, nine species of Dineutus and 12 species of Gyrinus. The family is distributed …


The Prairie Naturalist Volume 19, No.2. June 1987 Jun 1987

The Prairie Naturalist Volume 19, No.2. June 1987

The Prairie Naturalist

Paul B. Kannowski, Editor

Nikki R. Seabloom, Assistant Editor

Douglas H. Johnson, Book Review Editor

TABLE OF CONTENTS

WESTERN SNOWBERRY COMMUNITY STRUCTURE IN SOUTH CENTRAL NORTH DAKOTA ▪ D. R. Kirby and T. A. Ransom-Nelson

LIFE-FORMS AND GEOGRAPHIC AFFINITIES OF THE SOUTHEASTERN NORTH DAKOTA FLORA ▪ G. J. Seiler and W. T. Barker

THE EFFECT OF BURNING AND INSECT HERBIVORY ON SEED PRODUCTION OF TWO PRAIRIE FORBS ▪ M. A. Davis, K. M. Lemon, and A. M. Dybvig

CANVASBACK NESTING ON MAN-MADE ISLANDS IN MONTANA ▪ D. M. Prellwitz

CHRISTMAS BIRD COUNTS FOR NORTH DAKOTA - 1986 ▪ R. N. …


Karyotypic Analysis Of Five Rodents And A Marsupial From Belize, Central America, David W. Burton, John W. Bickham, Hugh H. Genoways, Timothy J. Mccarthy May 1987

Karyotypic Analysis Of Five Rodents And A Marsupial From Belize, Central America, David W. Burton, John W. Bickham, Hugh H. Genoways, Timothy J. Mccarthy

University of Nebraska State Museum: Mammalogy Papers

Karyotypes and chromosomal banding patterns of six species of small mammals from Belize are presented and discussed in light of relevant data in the literature. Individuals of Heteromys desmarestianus had FN values of 72, which differs from previous reports. G-bands were obtained and compared to fluorescent bands (DAPI) and with the location of NOR sites. The karyotypes of Peromyscus mexicanus, Sigmodon hispidus, Oryzomys couesi, and Ototylomys phyllotis are identical to the karyotypes for these species described in the literature. Active NORs were located on four pairs of chromosomes in O. phyllotis and fluorescent bands obtained with the …


Factors Affecting The Sprouting Response Of Woody Caatinga Species And Their Implications For Improved Caatinga Management, Linda Howell Hardesty May 1987

Factors Affecting The Sprouting Response Of Woody Caatinga Species And Their Implications For Improved Caatinga Management, Linda Howell Hardesty

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In northeast Brazil grazing is a major use of much of the semiarid woodlands (caatinga). Animal production is limited by lack of dry season forage, primarily deciduous tree leaves. Management is constrained by the persistence of undesirable trees that sprout from the stump (coppice). This study evaluates the possibility of manipulating coppicing trees to improve caatinga management, particularly dry season forage production.

The season of cutting can influence coppicing. Trees were cut early and late in the wet and dry seasons. After two years, trees of all species cut in the late wet season produced less biomass than those cut …


Las Vegas Wash And Lake Mead Proposed Water Quality Standards: Revisions And Rationale, State Of Nevada: Division Of Environmental Protection May 1987

Las Vegas Wash And Lake Mead Proposed Water Quality Standards: Revisions And Rationale, State Of Nevada: Division Of Environmental Protection

Publications (WR)

Rationale of review and for proposed changes to the Nevada Pollution Control Regulations (NAC 445.1354, 445.1355, 445.1356, 455.1367, 445.1352, 445.1353, 445.1350, 445.1351) before the State Environmental Commission on June 23 and 24, 1987.


Comparison Of Littoral And Limnetic Zooplankton Communities Of Lake Mead, Patrick Joseph Sollberger May 1987

Comparison Of Littoral And Limnetic Zooplankton Communities Of Lake Mead, Patrick Joseph Sollberger

Publications (WR)

Microfaunal communities were studied in littoral (inshore) and limnetic (offshore) areas of the lower basin in Lake Mead to compare species composition and abundance between the two zones. Planktonic forms (zooplankton) dominated inshore and offshore habitats and the occurrence of littoral species was low. Therefore, high similarity in zooplankton species composition was found among all sampling stations. This was perhaps due to two main factors: (i) the physical and chemical environment among the stations were very similar and (ii) the lack of aquatic vegetation in the littoral zone reduced the occurrence of littoral species.

Although species composition did not vary …


Impact Of Development On Traditional Pastoralism In Somalia, Abdulkadir A. Handulle May 1987

Impact Of Development On Traditional Pastoralism In Somalia, Abdulkadir A. Handulle

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

The Somali pastoral nomads live in an environmental condition of risk and uncertainty. The scarce and unreliable rainfall is the primary element ·which determines the existence of nomadic pastoralism. The lands devoted to pastoralism in Somalia are those arid and semi-arid areas that could not sustain cropping, so that pastoralism may be considered the only rational utilization of the land resource. Nomads live in an environment where the survival of both animals and plants are constrained by many factors such as droughts. Yet, both nomads and their animals have evolved by learning numerous adaptive strategies to cope with their harsh, …


Autecological And Grazing Control Studies Of Dyers Woad (Isatis Tinctoria L.) On Northern Utah Rangelands, Kassim O. Farah May 1987

Autecological And Grazing Control Studies Of Dyers Woad (Isatis Tinctoria L.) On Northern Utah Rangelands, Kassim O. Farah

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Dyers woad (Isatis tinctoria L.) is a noxious weed on northern Utah rangelands. Chemical and mechanical means of control are unsuitable for rangelands. A potential alternative, biological control, is difficult due to a lack of basic ecological information. To remedy this, some aspects of the population biology and autecolgy of dyers woad were studied. The feasibility of controlling dyers woad by early spring grazing was also investigated via clipping experiments.

A population study followed the survivorship of experimentally established populations over two years. Fall germinating individuals (1984) overwintered as rosettes twice and all survivors reproduced successfully. Spring germinating individuals …


Utilization Of Crested Wheatgrass Plants By Cattle Under Several Grazing Regimes, Patricia Selann Johnson May 1987

Utilization Of Crested Wheatgrass Plants By Cattle Under Several Grazing Regimes, Patricia Selann Johnson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Patterns of grazing on individual crested wheatgrass plants were studied using scale maps of plant basal outlines within randomly located plots. The occurrence and extent (part of plant grazed, stubble height) of grazing on each plant was recorded on the maps at two and three day intervals throughout a grazing treatment. Allometric equations for estimating phytomass from plant photosynthetic volume were generated using nonlinear regression analysis. Equations were specific to year. The percent weight remaining in the stubble of a grazed plant was estimated using a second-order polynomial equation relating cumulative percent plant height to cumulative percent plant weight. A …


Behavioral Feeding Specialization In Pinaroloxias Inornata, The “Darwin's Finch” Of Cocos Island, Costa Rica, Tracey K. Werner, Thomas W. Sherry Apr 1987

Behavioral Feeding Specialization In Pinaroloxias Inornata, The “Darwin's Finch” Of Cocos Island, Costa Rica, Tracey K. Werner, Thomas W. Sherry

Dartmouth Scholarship

As a population, Cocos Finches exhibit a broad range of feeding behaviors spanning those of several families of birds on the mainland, while individuals feed as specialists year-round. Although this extreme intraspecific variability occurs as predicted in a tropical oceanic island environment, these specializations challenge contemporary ecological theory in that they are not attributable to individual differences in age, sex, gross morphology, or opportunistic exploitation of patchy resources. Instead, they appear to originate and be maintained behaviorally, possibly via observational learning. This phenomenon adds another direction to the evolutionary radiation of the Darwin's Finches and underscores the necessity for detailed …


Attraction To Blood As A Factor In Tail-Biting By Pigs, David Fraser Apr 1987

Attraction To Blood As A Factor In Tail-Biting By Pigs, David Fraser

Abnormal Behavior Collection

Canvas models, about the size of a pig's tail, were impregnated with pigs' blood or left plain, and were presented to pigs for 12 days in a 2-choice preference test. The pigs showed large, consistent, individual differences in response: some pigs chewed the models continuously while others chewed only slightly; some chewed much more on the blood-covered model, while others showed no preference. On average, the pigs chewed considerably more on the blood-covered model than on the plain one. In a second experiment, pigs presented with a choice test involving a blood-covered and a plain model showed a significant increase …


Effect Of Changes In Regional Forest Abundance On The Decline And Recovery Of A Forest Bird Community, Robert A. Askins, Margarett J. Philbrick Mar 1987

Effect Of Changes In Regional Forest Abundance On The Decline And Recovery Of A Forest Bird Community, Robert A. Askins, Margarett J. Philbrick

Biology Faculty Publications

Bird populations were monitored for 32 years in a 23-ha tract of hemlock-hardwood forest. Between 1953 and 1976 the total abundance of long-distance migrants declined significantly and four species disappeared, but after 1976 both the total abundance and the number of species increased. Multiple regression analysis shows that the abundance of long-distance migrants was negatively related to abundance of bird species characteristic of suburban habitats and positively related to the amount of forest within 2 km of the study area. The decline in long-distance migrants before 1976 occurred when suburban species were increasing and nearby forest was destroyed. The increase …


The Prairie Naturalist Volume 19, No. 1 March 1987 Mar 1987

The Prairie Naturalist Volume 19, No. 1 March 1987

The Prairie Naturalist

Paul B. Kannowski, Editor

Nikki R. Seabloom, Assistant Editor

Douglas H. Johnson, Book Review Editor

TABLE OF CONTENTS

ECOLOGY OF WHITE-TAILED DEER IN UPLAND PONDEROSA PINE HABITAT IN SOUTHEASTERN MONTANA ▪ G. L. Dusek

PRECISION AND BIAS OF A SUMMER AERIAL TRANSECT CENSUS OF PRONGHORN ANTELOPE ▪ S. H. Allen and J. M. Samuelson

ACTIVITY PATTERNS, MOVEMENTS, AND HOME RANGES OF PRAIRIE MINK ▪ T. W. Arnold and E. K. Fritzell

BRYOPHYTES OF THE SOUTH UNIT OF THEODORE ROOSEVELT NATIONAL PARK, NORTH DAKOTA ▪ C. L. Blaney and D. H. Norris

FALL FOOD HABITS OF WILD TURKEYS IN SOUTH CENTRAL …


Book Review Of Evolution As Religion, Carl J. Bajema Mar 1987

Book Review Of Evolution As Religion, Carl J. Bajema

Other Scholarly Publications

No abstract provided.


Western Rock Lobster Industry Compensation Study. Report To The Rock Lobster Industry Advisory Committee By Arthur Young Services., Arthur Young Services Feb 1987

Western Rock Lobster Industry Compensation Study. Report To The Rock Lobster Industry Advisory Committee By Arthur Young Services., Arthur Young Services

Fisheries Management Papers

Terms of reference are outlined in letter dated 11 August 1986. The Fisheries Department seeks to reduce western rock lobster fishing capacity to ensure the long-term viability of the fishery and has asked us to evaluate the financial implications of a number of specific resource management proposals.


Residual Pesticides In Fishes From Lake Chicot, Arkansas, C. M. Cooper, S. S. Knight Jan 1987

Residual Pesticides In Fishes From Lake Chicot, Arkansas, C. M. Cooper, S. S. Knight

Journal of the Arkansas Academy of Science

Samples of fish from isolated and flow-through portions of Lake Chicot, Arkansas, were analyzed for residual pesticide concentrations from 1978 and 1981. Where appropriate ecologically, fish flesh, viscera and whole fish, were analyzed for the common organochlorine insecticides DDT [1,1 ,1-trichloro -2,2bis(p-chlorophenyl)-ethane], DDE [1,1-dichloro-2,2-bis(p-chlorophenyl)-ethyene], DDD [1,1-dichloro -2,2-bis(p-chlorophenyl)-ethane], toxaphene (chlorinated camphene), chlordane, heptachlor, heptachlor epoxide, dieldrin, and endrin. DDT, DDT metabolites, and heptachlor were significantly (a = 0.05) higher in spotted gar (Lepisosteus oculatus) and yellow bullhead catfish (Ictalurus natalis) than in other species examined. Pesticide concentrations did not exceed the acceptable levels established by the U.S. Environmental Protection Agency although …


Report Of The Rock Lobster Industry Advisory Committee Meeting Of 27 January 1987 - Report By The Chairman Mr. B.K. Bowen., B. K. Bowen Jan 1987

Report Of The Rock Lobster Industry Advisory Committee Meeting Of 27 January 1987 - Report By The Chairman Mr. B.K. Bowen., B. K. Bowen

Fisheries Management Papers

The Rock Lobster Industry Advisory Committee met in Perth on Tuesday 17 January 1987. Committee discussed the following: Policy on 5% pot loss on replacement of vessels less than six years old. Study of industry funded compensation mechanism for fishing capacity reductions. 20 Fathom rule. Future maintenance of the zone E boundary. The recreational Rock Lobster Fishery. Rock Lobster pot distribution. Options for a 10 per cent reduction in fishing effort. 1987 coastal tour. Augusta-Windy Harbour Rock Lobster Working Group. Report on the 1986/87 season.


Some Potential Evolutionary Costs Associated With Paternal Care In The Water Bug Belostoma Flumineum Say, Larry Johnson Jan 1987

Some Potential Evolutionary Costs Associated With Paternal Care In The Water Bug Belostoma Flumineum Say, Larry Johnson

Masters Theses

Female water bugs (Belostoma flumineum) deposit eggs in a mucilaginous cement on the back of conspecific males, who then brood these eggs until hatching. Sex role reversal, in which females compete for males and males are discriminating, is predicted in this species because males provide parental care exclusively, and represent a limited resource. Presumably the advantage of this paternal behavior is increased survival of young. However, the potential exists for this egg-brooding behavior to incur evolutionary costs, and quantifying some of these costs was the thrust of this study.

One cost, a loss of polygynous opportunity, was investigated …


Characteristics Of Successful Competitors: An Evaluation Of Potential Growth Rate In Two Cold Desert Tussock Grasses, Eissenstat D. M., Caldwell M. M. Jan 1987

Characteristics Of Successful Competitors: An Evaluation Of Potential Growth Rate In Two Cold Desert Tussock Grasses, Eissenstat D. M., Caldwell M. M.

Aspen Bibliography

Within the first few weeks after seedling emergence, Agropyron desertorum, a more competitive tussock grass, had a much higher mean relative growth rate (RGR) than Agropyron spicatum, a very similar, but less competitive species. However, beyond the early seedling stage, the two grasses had a remarkably similar whole-plant RGR in hydroponic culture and aboveground RGR in glasshouse soil, if root temperatures were above approximately 12° C. At soil temperatures between 5 and 12° C, A. desertorum exhibited a 66% greater aboveground RGR than A. spicatum (P < 0.05). Both species responded similarly to warming soil temperatures. In the field, however, tiller growth rates were generally similar. Neither species showed marked tiller elongation until a couple of weeks after snowmelt, by which time soil temperatures, at least to a depth of 10 cm, were above 12° C for a significant portion of the day. Above-ground biomass accumulation over a three-year period indicated that both grasses had similar potential growth rates whereas Artemisia tridentata ssp. vaseyana, a common neighbor planted in the same plots, had a much greater potential growth rate. The greater competitive ability of adult A. desertorum, as compared to A. spicatum, cannot be attributed to appreciable differences in potential growth rates.


Distribution And Current Status Of The Threatened Dismal Swamp Southeastern Shrew, Sorex Longirostris Fisheri, Robert K. Rose, Roger K. Everton, Thomas M. Padgett Jan 1987

Distribution And Current Status Of The Threatened Dismal Swamp Southeastern Shrew, Sorex Longirostris Fisheri, Robert K. Rose, Roger K. Everton, Thomas M. Padgett

Biological Sciences Faculty Publications

The Dismal Swamp southeastern shrew, Sorex longirostris fisheri, was given "Threatened" status by the U.S. Fish and Wildlife Service in 1986 because of its limited distribution and the potential threat of interbreeding with the nearby upland subspecies, Sorex l. longirostris. Known from about 20 specimens collected before 1980 and a few dozen taken since then, "fisheri" seems to have morphologically diverged from the smaller upland "longirostris" in association with the development of the Dismal Swamp. The detection of southeastern shrews that are intermediate in size between the two subspecies, coupled with the location of these collection sites on …


Hyla Versicolor-Chrysoscelis Species Complex Of Gray Treefrogs In Arkansas: Histological And Ultrastructural Evidence, Phyllis Chaffin, Stanley E. Trauth Jan 1987

Hyla Versicolor-Chrysoscelis Species Complex Of Gray Treefrogs In Arkansas: Histological And Ultrastructural Evidence, Phyllis Chaffin, Stanley E. Trauth

Journal of the Arkansas Academy of Science

We investigated the Hyla versicolor-chrysoscelis species complex (tetraploid and diploid species, respectively) of cryptic gray treefrogs from Arkansas using light and scanning electron microscopy. From previous studies of this treefrog complex in other states, H. versicolor has been shown to exhibit larger nuclear diameters and larger toe pad epithelial cells than H. chrysoscelis. Based upon average nuclear diameters of eyelid epithelial cells, we found two or possibly three groups of frogs. The presumed H. versicolor exhibited greatly enlarged toe pad epithelial cells using scanning electron microscopy and were found in four counties, three of which are in the Ozark Mountains. …


Status Of The Instream Flow Issue In Arkansas, 1987, Stephen P. Filipek, William E. Keith, John Giese Jan 1987

Status Of The Instream Flow Issue In Arkansas, 1987, Stephen P. Filipek, William E. Keith, John Giese

Journal of the Arkansas Academy of Science

Expansion of Arkansas' population with concurrent increases in the state's domestic, industrial, and agricultural water uses and possible out-of-state diversion are placing substantial demands on the state's water resources. In an attempt to address this growing concern, Act 1051 (1985) of the Arkansas legislature was passed requiring the determination of present and future state water needs. A specific area of this mandate was the quantification of instream flow requirements. Basic instream flow needs are maintenance of the aquatic ecosystem and dependent riparian environment. Flow reservation may compliment other instream uses such as recreation, navigation, water quality, and groundwater recharge. However, …


The Identification Of The Threatened Southeastern Shrew Using Multivariate Statistical Techniques, Thomas M. Padgett, Roger K. Everton, Robert K. Rose Jan 1987

The Identification Of The Threatened Southeastern Shrew Using Multivariate Statistical Techniques, Thomas M. Padgett, Roger K. Everton, Robert K. Rose

Biological Sciences Faculty Publications

The threatened subspecies of the southeastern shrew, Sorex longirostris fisheri, is endemic to the Great Dismal Swamp of southeastern Virginia. Previous studies based on discriminant analysis of external measurements determined that intergrades with the upland form, Sorex l. longirostris, exist along the periphery of the Swamp. To better discriminate among these populations, a study of cranial morphology was initiated. Fifteen cranial measurements were taken, using 59 specimens of Sorex collected previously form southeastern Virginia, including the Dismal Swamp. Both Principal Component and Cluster Analyses revealed no significant cranial variation or morphometric patterns within the specimens examined, but a …


A Synthetic Approach To The Study Of Animal Intelligence, Alan Kamil Jan 1987

A Synthetic Approach To The Study Of Animal Intelligence, Alan Kamil

Papers in Behavior in Biological Sciences

Psychologists have been studying animal learning for about a century. This century of experimental and theoretical work has produced some remarkable successes, particularly in understanding basic conditioning processes. However, these successes are limited in two major ways. First, they have been confined to a narrow domain. Recent research from a variety of settings has demonstrated that animals have mental abilities far beyond what they were given credit for just a few years ago. We must dramatically expand the range of phenomena addressed by the study of animal learning. Second, there has been an almost complete failure to place animal learning …


Alloparental Care In The Prairie Skink, Eumeces Septentrionalis: A Case Of Mistaken Identity?, Louis A. Somma Jan 1987

Alloparental Care In The Prairie Skink, Eumeces Septentrionalis: A Case Of Mistaken Identity?, Louis A. Somma

Papers in Herpetology

Alloparental care , or one individual caring for the eggs or young of another , ha s been documented for a variety of verte brate organism s (Coyne & Sohn 1978; Frame et a1. 1983; Gowaty & Karlin 1984) . In t h i s a rticle I document an instance of alloparental care in the prairie skink , Eumeces septentrionalis .


Morphological Variation, Karyology, And Systematic Relationships Of Heteromys Gaumeri (Rodentia: Heteromyidae), Mark D. Engstrom, Hugh H. Genoways, Priscilla K. Tucker Jan 1987

Morphological Variation, Karyology, And Systematic Relationships Of Heteromys Gaumeri (Rodentia: Heteromyidae), Mark D. Engstrom, Hugh H. Genoways, Priscilla K. Tucker

University of Nebraska State Museum: Mammalogy Papers

Morphological variation was assessed within and among populations of Heteromys gaumeri using univariate and multivariate statistical analyses of external and cranial measurements. Although patterns and amount of nongeographic variation in H. gaumeri were similar to other heteromyines, geographic variation was relatively conservative. Mean values of most characters were statistically homogeneous among localities and spatially unpatterned. Consequently, no association was found between levels of within- and among-sample variation for individual characters (the "Kluge-Kerfoot phenomenon"). Populations of H. gaumeri were chromosomally monomorphic. The lack of morphological and chromosomal variation in H. gaumeri contrasts sharply with patterns in other heteromyines. Heteromys gaumeri is …