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 18931 - 18960 of 19670

Full-Text Articles in Entire DC Network

Nutritional Quality And Herbage Production Of Intermediate Wheatgrass (Agropyron Intermedium [Host] Beauv.) When Infested With Black Grass Bugs (Labops Hesperius Uhler), Alan M. Gray May 1975

Nutritional Quality And Herbage Production Of Intermediate Wheatgrass (Agropyron Intermedium [Host] Beauv.) When Infested With Black Grass Bugs (Labops Hesperius Uhler), Alan M. Gray

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Two intermediate wheatgrass seedings with different levels of grass bug infestation were evaluated for herbage production, seedhead production, percent dry matter, crude protein, and cell contents. Study sites were located at different elevations on mountain summer ranges in northern (Site I) and central (Site II) Utah. Study plots at Site I and Site II were infested with 113 and 210 bugs per sweep, respectively. Herbage production appeared to be reduced in early spring on the site with the higher infestation; however, no effect on season-long herbage production could be detected on either site. Seedhead production on infested plots was reduced …


Exploratory Sensitivity Analysis Of A Stream Ecosystem Model, Joseph H. Wlosinski May 1975

Exploratory Sensitivity Analysis Of A Stream Ecosystem Model, Joseph H. Wlosinski

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The framework of a stream ecosystem simulation model is described. Using this framework and data from two different geographical areas, a cold desert stream and a generalized mountain stream, exploratory sensitivity analysis was performed on the model. This was accomplished by qualitatively comparing outputs of a series of simulations in which a different level of a driving variable was used in each simulation. Based on these results, recommendations are made for improving the structure of the model.


Plant Light Responses Under Snow, Steven G. Richardson May 1975

Plant Light Responses Under Snow, Steven G. Richardson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Several montane plant species and one alpine species were observed to grow under snow, and the seeds of 19 species germinated under snow. The spectral irradiance of light penetrating up to 198 cm of snow was measured with a device employing a photomultiplier tube and a series of interference filters. In deep snow, the measured peak in transmission was near 500 nm, but in older, more shallow snow the peak was at 550 nm. On two occasions measurements were made both before and after sunrise. There was a shift in the spectra toward the longer wavelengths as the sun rose …


A New Subspecies Of Geomys Bursarius (Mammalia: Geomyidae) From Texas And New Mexico, Robert J. Baker, Hugh H. Genoways Apr 1975

A New Subspecies Of Geomys Bursarius (Mammalia: Geomyidae) From Texas And New Mexico, Robert J. Baker, Hugh H. Genoways

University of Nebraska State Museum: Mammalogy Papers

As part of a study of the systematics and ecology of pocket gophers occurring on the high plains of Texas and eastern New Mexico, numerous populations of the plains pocket gopher, Geomys bursarius, were examined karyotypically. Four chromosomal races were described from this area by Baker et al. (1973). Additional studies lead us to believe that two of these races represent an undescribed subspecies of the plains pocket gopher. In addition to karyological evidence, specimens of this subspecies are morphologically distinct from those of all contiguous populations of Geomys bursarius major, the race to which they previously were assigned. …


Mammals Of The Guadalupe Mountains National Park, Texas, Hugh H. Genoways, Robert J. Baker, John E. Cornely Apr 1975

Mammals Of The Guadalupe Mountains National Park, Texas, Hugh H. Genoways, Robert J. Baker, John E. Cornely

University of Nebraska State Museum: Mammalogy Papers

Our survey began in late May 1973 and continued through August 1975. The objectives of our study, which was supported by the National Park Service, were to survey the mammals occurring in the Guadalupe Mountains National Park, Texas, and to correlate their distribution with major plant associations. This inventory of the natural resources of the park is preliminary to the development of any serious management program. Therefore, we present the following accounts to serve as baseline data for future mammalian work in the park and development of the master plan for the park.


Editors' Note To Biological Investigations In The Guadalupe Mountains National Park, Texas., Hugh H. Genoways, Robert J. Baker Apr 1975

Editors' Note To Biological Investigations In The Guadalupe Mountains National Park, Texas., Hugh H. Genoways, Robert J. Baker

University of Nebraska State Museum: Mammalogy Papers

The Guadalupe Mountains National Park, which is located in TransPecos Texas between Carlsbad, New Mexico, and EI Paso, Texas, is one of the newest national parks being formed by the Congress in 1967. The Guadalupe Mountains and the associated Chihuahuan Desert included in the park represent a unique biological area in which a fragile biological equilibrium exists between the fauna and flora of the Chihuahuan Desert of the lowlands and the Rocky Mountains of the high elevations. The preservation of this area will depend upon sound management decisions. This volume is the result of a symposium held at The Museum …


Limnological Investigation Of The Muskegon County, Michigan, Wastewater Storage Lagoons, W. Randolph Frykberg Apr 1975

Limnological Investigation Of The Muskegon County, Michigan, Wastewater Storage Lagoons, W. Randolph Frykberg

Masters Theses

No abstract provided.


A Comparative Study Of Some Population Characteristics Of Calyptraea Fastigiata Gould, Crepidula Lingulata Gould, And Crepidula Nummaria Gould (Gastropoda, Prosobranchia), Roger Harold Goodwill Apr 1975

A Comparative Study Of Some Population Characteristics Of Calyptraea Fastigiata Gould, Crepidula Lingulata Gould, And Crepidula Nummaria Gould (Gastropoda, Prosobranchia), Roger Harold Goodwill

Theses and Dissertations

A comparative study of the field populations of Crepidula lingulata, Crepidula nurnmaria, and Calyptraea fastigiata indicated all three preferred a rocky substrate but favored different size rocks. Their positions on the rocks varied but the greatest numbers were found attached to the undersides. Crepidula lingulata and C. nummaria preferred larger rocks and were found in intraspecific associations more often than C. fastigiata which preferred smaller rocks. These associations occurred with a 1:1 sex ratio; however, the overall population did not. Crepidula lingulata had a high female count and C. fastigiata a high male count. Males, of all three species, were …


Diatom Phytoplankton And Periphyton Studies Of The Headwaters Of Henrys Fork Of The Snake River, Island Park, Idaho, Richard L. Clark Apr 1975

Diatom Phytoplankton And Periphyton Studies Of The Headwaters Of Henrys Fork Of The Snake River, Island Park, Idaho, Richard L. Clark

Theses and Dissertations

An ecological baseline study of the diatom flora was conducted on the headwaters of Henrys Fork of the Snake River, Idaho. The diatom flora of this spring fed drainage basin consisted of both phytoplankton and periphyton. Thirty-nine genera, two hundred forty-four species, eighty-two additional varieties, and seven additional forms were identified from these waters. Species of Melosira, Stephanodiscus, Fragilaria, Synedra, and Asterionella were found in the plankton of Henrys Lake and Island Park Reservoir. Diatoma, Fragilaria, Synedra, Eunotia, Achnanthes, Navicula, Pinnularia, Gomphonema, Cymbella, Nitzschia, and Surirella were the important genera present in the periphyton.


Special Report On Zoo Reform Mar 1975

Special Report On Zoo Reform

Special Reports

The Humane Society of the United States has taken the lead for the past 3 1/2 years in reforming American zoos. HSUS has awakened Americans to the fact that wild animals have been caged inhumanely for many decades in the nation's zoos and that major and drastic actions are necessary to correct these problems. While HSUS has continued to insist that no wild animal should be exploited simply to create an attraction or exhibit, such is not the state of the world as it exists today. Consequently, HSUS is determined to do everything in its power to alleviate the suffering …


The Prairie Naturalist Volume 7, No.1. March 1975 Mar 1975

The Prairie Naturalist Volume 7, No.1. March 1975

The Prairie Naturalist

MIGRATION OF BIRDS IN NORTH DAKOTA DURING FAll 1974 ▪ J. T. Lokemoen & D. H. Johnson.

REPRODUCTION AND DEVELOPMENT OF FOUR MALLARD LINES ▪ R. J. Greenwood


A New Kimballian Peccary From Nebraska, C. Bertrand Schultz, Larry D. Martin Feb 1975

A New Kimballian Peccary From Nebraska, C. Bertrand Schultz, Larry D. Martin

Bulletin of the University of Nebraska State Museum (1924–2023)

A new species of Pliocene peccary, Prosthennops (Macrogens) graffhami; is described from the Kimball Formation, Ogallala Group, Frontier County, Nebraska. This new species is the latest in geologic age and most advanced in the genus.

The remains of fossil vertebrates are generally rare in the upper part of the Ogallala group, and some have maintained that Hemphillian faunas such as Coffee Ranch and Smith County, Kansas, represent the latest Ogallala faunas. Later faunas than are typically considered as Hemphillian, containing more advanced forms, occur in the Kimball Formation and deposits of equivalent age. Known faunas which may …


Bears (Ursidae) From The Late Cenozoic Of Nebraska, C. Bertrand Schultz, Larry D. Martin Feb 1975

Bears (Ursidae) From The Late Cenozoic Of Nebraska, C. Bertrand Schultz, Larry D. Martin

Bulletin of the University of Nebraska State Museum (1924–2023)

A ramus and partial premaxilla establish the presence of a new subspecies of Indarctos in the upper Pliocene (Kimball Formation, Ogallala Group) of Frontier County, Nebraska. An extremely large species of Agriotherium is represented by fragmentary remains from the middle Pliocene (middle part of Ash Hollow Formation, Ogallala Group) of Sherman County, Nebraska.

This study is part of a series of papers dealing primarily with the fauna of the Kimball formation in Nebraska (Barbour 1927, 1929; Barbour and Schultz, 1941; Schultz and Stout, 1948, 1961; Kent 1963, 1967; Tanner, 1967; Short, 1969; Martin and Tate, 1970; Schultz, Schultz, and Martin, …


Scimitar-Toothed Cats, Machairodus And Nimravides, From The Pliocene Of Kansas And Nebraska, Larry D. Martin, C. Bertrand Schultz Feb 1975

Scimitar-Toothed Cats, Machairodus And Nimravides, From The Pliocene Of Kansas And Nebraska, Larry D. Martin, C. Bertrand Schultz

Bulletin of the University of Nebraska State Museum (1924–2023)

"Machairodus catocopis Cope" is shown to be a pseudaelurin cat belonging to the genus Nimravides Kitts. Nimravides thinobates (Macdonald) is a possible synonym of N. catocopis (Cope). Nimravides is compared with the Eurasian Machairodus-like cat, Dinofelis. Machairodus (Heterofelis) coloradensis is reported from the Kimball Formation, upper Pliocene (Kimballian) of Cheyenne County, Nebraska, and from the upper part of the Ash Hollow Formation, Pliocene (Hemphillian) of Sherman County, Nebraska. The Kimballian form is described as a new subspecies, Machairodus coloradensis tanneri.

The genus Machairodus has long been associated with the Hemphillian of North America and the …


Cenozoic Mammals From The Central Great Plains, C. Bertrand Schultz, Larry D. Martin, R. George Corner, Lloyd G. Tanner Feb 1975

Cenozoic Mammals From The Central Great Plains, C. Bertrand Schultz, Larry D. Martin, R. George Corner, Lloyd G. Tanner

Bulletin of the University of Nebraska State Museum (1924–2023)

Includes:

Part 1. Middle and Late Cenozoic Tapirs from Nebraska. By C. Bertrand Schultz, Larry D. Martin, and R. George Corner.

Part 2. Stratigraphic Occurrences of Teleoceras, with a New Kimballian Species from Nebraska. By Lloyd G. Tanner.

Part 3. A New Kimballian Peccary from Nebraska. By C. Bertrand Schultz and Larry D. Martin.

Part 4. Bears (Ursidae) from the Late Cenozoic of Nebraska. By C. Bertrand Schultz and Larry D. Martin.

Part 5. Scimitar-toothed Cats, Machairodus and Nimravides, from the Pliocene of Kansas and Nebraska. By Larry D. Martin and C. Bertrand Schultz.

84 pp


The Surveillance Of Rodent Populations In East Africa In Relation To Plague Endemicity, S. Msangi Jan 1975

The Surveillance Of Rodent Populations In East Africa In Relation To Plague Endemicity, S. Msangi

Tanzania Journal of Science

Plague has been endemic in East Africa from very early times. The fact that the plague organism occurring in the area is mostly Pasteurella pestis var. antiqua which is said to have been associated with the Justinian pandemic of the 6th century A. D. would seem to support the contention that this endemicity was established during that pandemic. The maintenance of this endemicity has been made possible by the presence in the area of suitable rodent reservoirs, efficient flea vectors and favourable climatic and ecological conditions. The main reservoirs of plague in East Africa are Rattus rattus, Praomys natalensis and …


Annotated Checklist Of Mammals Of The Yucatán Peninsula, México. Iv. Carnivora, Sirenia, Perissodactyla, Artiodactyla, Hugh H. Genoways, Robert J. Baker Jan 1975

Annotated Checklist Of Mammals Of The Yucatán Peninsula, México. Iv. Carnivora, Sirenia, Perissodactyla, Artiodactyla, Hugh H. Genoways, Robert J. Baker

University of Nebraska State Museum: Mammalogy Papers

This is the fourth in a series of papers by Jones, et al., dealing with the systematics and distributional status of mammals on the Yucatán Peninsula of México. The present contribution lists 24 native species belonging to the orders Carnivora (18 species), Sirenia (one), Perissodactyla (one), and Artiodactyla (four). Among the carnivores there are one canid, six procyonids, six mustelids, and five felids, whereas the Artiodactyla is represented by two families (Tayassuidae and Cervidae), each with two species.

The Yucatán Peninsula as treated in this series of papers includes the Mexican states of Campeche and Yucatan, and the Federal Territory …


The Primitive Hunter Culture, Pleistocene Extinction, And The Rise Of Agriculture, Vernon L. Smith Jan 1975

The Primitive Hunter Culture, Pleistocene Extinction, And The Rise Of Agriculture, Vernon L. Smith

Economics Faculty Articles and Research

The hypothesis that megafauna extinction some 10,000 years ago was due to "overkill" by Paleolithic hunters is examined using an economic model of a replenishable resource. The large herding animals that became extinct, such as mammoth, bison, camel, and mastodon, presented low hunting cost and high kill value. The absence of appropriation provided incentives for the wastage killing evident in some kill sites, while the slow growth, long lives, and long maturation of large animals increased their vulnerability to extinction. Free-access hunting is compared with socially optimal hunting and used to interpret the development of conservationist ethics, and controls, in …


Phomopsis : The Causal Fungus Of Lupinosis, P Mcr Wood, A. G. P. Brown Jan 1975

Phomopsis : The Causal Fungus Of Lupinosis, P Mcr Wood, A. G. P. Brown

Journal of the Department of Agriculture, Western Australia, Series 4

It is now well known that lupinosis of sheep and cattle follows ingestion of lupin stubble colonised by the fungus Phomopsis rossiana. The fungus infects green lupins but persists on the stubble and under certain conditions apparently produces a toxin which causes the disease.

As Phomopsis is now widespread on lupins in Western Australia its ecology has been studied in detail as a basis for possible control measures.

This article outlines what is known so far of the disease and its control.


The Behaviour Of Swine, J. P. Signoret, B. A. Baldwin, D. Fraser, E. S. E. Hafez Jan 1975

The Behaviour Of Swine, J. P. Signoret, B. A. Baldwin, D. Fraser, E. S. E. Hafez

Mammalogy Collection

The pig was a forest-dwelling animal from the beginning of its history. In some parts of the world it has been domesticated for at least 7000 years. The European breeds of domestic swine were derived from the local wild pig, Sus scrofa. Herds ranged in pastures and forests and kept indoors only for fattening. The breeds in the Far East were derived from another wild pig, Sus vittatus, a smaller animal with shorter legs and a higher reproductive ability (Mohr 1960; Zeuner 1963). The two types interbred readily. The modem breeds of pig evolved from different crossings between the two …


Special Report On Controlling America's Pet Population Jan 1975

Special Report On Controlling America's Pet Population

Special Reports

HSUS estimates that public and private animal control programs cost the nation as much as $500 million a year. Much of this expense is required for the feeding and care of unwanted animals during the 5 to 10 days they are held for adoption, killing the 80% that are not adopted or redeemed, and disposing of the carcasses. The result is both an unconscionable waste of life and a needless drain on public and private money.

A large part of the blame for people undertaking pet ownership without having made a total commitment to the animal lies with the pet …


Aquatic Ascomycetes From Lake Itasca, Minnesota, A. R. Cavaliere Jan 1975

Aquatic Ascomycetes From Lake Itasca, Minnesota, A. R. Cavaliere

Biology Faculty Publications

A preliminary report of the aquatic Ascomycetes of Lake Isasca, Minnesota. Included is an introduction, methods of harvesting and studying, a key, description, and illustrations of 19 common ascomycetous fungi inhabiting the study area.


Biological Control Of Insects On The Ord. 1. Production Of Sitotroga Cerealella For Mass Rearing Of Trichogramma Wasps, M Grimm, P. J. T. Lawrence Jan 1975

Biological Control Of Insects On The Ord. 1. Production Of Sitotroga Cerealella For Mass Rearing Of Trichogramma Wasps, M Grimm, P. J. T. Lawrence

Journal of the Department of Agriculture, Western Australia, Series 4

Department of Agriculture entomologists have developed a technique for the production and collection of eggs of the Angoumois grain moth (Sitotroga cerealella) for mass-rearing the parasitic waspTrichogramma pretiosum Riley.

Trichogramma is giving promising results in trials aimed at developing biological control of insect pests in the Ord River Irrigation Area.


Middle And Late Cenozoic Tapirs From Nebraska, C. Bertrand Schultz, Larry D. Martin, R. George Corner Jan 1975

Middle And Late Cenozoic Tapirs From Nebraska, C. Bertrand Schultz, Larry D. Martin, R. George Corner

Bulletin of the University of Nebraska State Museum (1924–2023)

The distribution and evolution of Late Cenozoic tapirs are discussed and the forms present in Nebraska are reported. Two new species are described from the Ogallala Pliocene of Nebraska, ?Tapirus johnsoni and ?T. simpsoni. Tapirs are known in Nebraska from the Early Oligocene through the Middle Pleistocene. The northern limit of the distribution of the tapirs contracts gradually southward in North America throughout the Tertiary, and even during the Pleistocene interglacials Nebraska must have been near the northern limit of their range.


Stratigraphic Occurrences Of Teleoceras With A New Kimballianspecies From Nebraska, Lloyd G. Tanner Jan 1975

Stratigraphic Occurrences Of Teleoceras With A New Kimballianspecies From Nebraska, Lloyd G. Tanner

Bulletin of the University of Nebraska State Museum (1924–2023)

Study of Teleoceras remains in the University of Nebraska State Museum indicates that this specialized, short-limbed rhinoceros inhabited the Central Great Plains from Early through Late Pliocene. Previously thought to have become extinct at the end of the middle Pliocene, this genus is now known from the very latest Pliocene. A new species, Teleoceras schultzi, is described from the Kimball Formation, Ogallala Group, Frontier County, Nebraska.


Preliminary Dove Banding Studies In Clark County, Arkansas, Thurman Booth, Peggy Rae Dorris, William N. Hunter, Benny Mays Jan 1975

Preliminary Dove Banding Studies In Clark County, Arkansas, Thurman Booth, Peggy Rae Dorris, William N. Hunter, Benny Mays

Journal of the Arkansas Academy of Science

In conjunction with the U.S. Department of Interior Fish and Wildlife Service, Henderson State University Biology Department made a preliminary study of mourning doves in Clark County, Arkansas, during June, July and August 1974. Three hundred seventy-one mourning doves were baited, trapped and banded to obtain information concerning age, sex, populations, retraps, deformities, effects on other animals, migrations and other behaviors.


Preliminary Checklist Of The Fishes Of The Illinois River, Arkansas, Michael R. Geihsler, Edgar D. Short, Paul D. Kittle Jan 1975

Preliminary Checklist Of The Fishes Of The Illinois River, Arkansas, Michael R. Geihsler, Edgar D. Short, Paul D. Kittle

Journal of the Arkansas Academy of Science

A survey of the fishes of the mainstream of the Illinois River in northwestern Arkansas produced 51 species representing 11 families. Four of these species, Ictiobus bubalus, smallmouth buffalo; Moxostoma carinatum, river redhorse; Lepomis gulosus, warmouth; and Percina phoxocephala, slenderhead darter, have not been recorded previously from the Arkansas part of the Illinois. Eleven additional species have been reported previously that were not collected during this survey, for a total of 62 species known in the Illinois River.


Age And Growth Of Bluegill, Lepomis Macrochirus Rafinesque, From Lake Fort Smith, Arkansas, Jacob J. Hogue, Raj V. Kilambi Jan 1975

Age And Growth Of Bluegill, Lepomis Macrochirus Rafinesque, From Lake Fort Smith, Arkansas, Jacob J. Hogue, Raj V. Kilambi

Journal of the Arkansas Academy of Science

A total of 337 bluegill from Lake Fort Smith were used for this study. Annuli were formed between late February and early June, the younger fish forming annuli earlier than older fish. Total length-scale radius and length-weight relationships were determined. Growth of bluegill was compared with that reported in other studies. Growth curves were analyzed by the Von Bertalanffy growth formula and the parameters were evaluated in terms of physical and biological factors.


Arkansas Butterflies And Skippers, Leo J. Paulissen Jan 1975

Arkansas Butterflies And Skippers, Leo J. Paulissen

Journal of the Arkansas Academy of Science

Since 1955 the writer has been compiling information on Arkansas butterflies and skippers. A list of species is presented from data obtained from personal collecting, extensive contacts with contemporary collectors, and a concerted literature search. A total of 151 species are listed on a chart which also shows from which of five designated areas in the state each species has been reported.


A Statistical Approach To The Study Of The Ecosystems Of Seven Ponds In East-Central Illinois, Gregory Lee Orr Jan 1975

A Statistical Approach To The Study Of The Ecosystems Of Seven Ponds In East-Central Illinois, Gregory Lee Orr

Masters Theses

Gross primary productivity, heterotrophic bacterial numbers, and net phytoplankton densities of seven ponds in Coles County, Illinois, were studied in relation to physical, chemical, and biological habitat variables (light intensity and duration, turbidity, water temperature, pH, dissolved oxygen, sulfur, nitrogen, phosphorus, production, bacteria, and phytoplankton). Ten observations were made for each pond (except where otherwise noted) from 17 June through 25 August 1974. Stepwise multiple linear regression analyses of the data were used in order to determine those environmental factors which were important in predicting (i.e., significantly correlated with) bacterial and phytoplankton densities, and production. A multiple linear regression equation …