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Full-Text Articles in Zoology

The Ecology And Life History Of The Mexican Tetra, Astyanax Mexicanus, (Teleostei: Characidae) In The Lower Rio Grande Valley, Texas, Mario Estrada May 1999

The Ecology And Life History Of The Mexican Tetra, Astyanax Mexicanus, (Teleostei: Characidae) In The Lower Rio Grande Valley, Texas, Mario Estrada

Theses and Dissertations - UTB/UTPA

The Mexican tetra has been found to migrate from shallow waters in the spring and summer months into deeper waters during the winter months when temperatures are too cold for their survival. This fish is omnivorous with insect material being the major source of food. Its food types include green algae, nematoceran larvae, hemipterans, coleopterans, hymenopterans, dipterans, ostracods, fish eggs and amphipods. Furthermore, size classes showed that the Mexican tetras reached their largest size at the River site and smaller sizes at the Bridge and Gate sites and apparently breed year round. They are capable of producing from 300 to …


Conservation Status Of The Southern Appalachian Herpetofauna, Joseph C. Mitchell, Thomas K. Pauley, David I. Withers, Steven M. Roble, Brian T. Miller, Alvin L. Braswell, Paul V. Cupp Jr., Christopher S. Hobson Apr 1999

Conservation Status Of The Southern Appalachian Herpetofauna, Joseph C. Mitchell, Thomas K. Pauley, David I. Withers, Steven M. Roble, Brian T. Miller, Alvin L. Braswell, Paul V. Cupp Jr., Christopher S. Hobson

Virginia Journal of Science

Seventy one species of amphibians (55 salamanders, 16 anurans) and 46 species of reptiles (15 turtles, 8 lizards, 23 snakes) inhabit a five state area (Kentucky, North Carolina, Tennessee, Virginia, West Virginia) in the southern Appalachian region bordered by the Potomac River, the Blue Ridge Mountains, and the western margin of the Appalachian Plateau. Of these, 47.9 % of the amphibian fauna and 52.2 % of the reptilian fauna are listed as being of conservation concern by federal, state, and Natural Heritage programs in all or a portion of their ranges of this region. The Shenandoah salamander (Plethodon Shenandoah …


Chemical Communication Of Estrous Cycle Status And Change In Social Behaviors With Reproductive State In Captive Female Asian Elephants, Elephas Maximus, Barbara Elaine Slade Feb 1999

Chemical Communication Of Estrous Cycle Status And Change In Social Behaviors With Reproductive State In Captive Female Asian Elephants, Elephas Maximus, Barbara Elaine Slade

Dissertations and Theses

Elephants use several well-developed sensory systems for communicating within and between social groups. Female elephants sniff, touch and flehmen to the urine and genitals of herdmembers. In addition, communication through social behaviors is prevalent. Female elephants frequently communicate through affiliate tactile and aggressive behaviors. Furthermore, although female elephants are not known to display behavioral signs of estrus, these females exhibit a tail slapping behavior that may be an implement for dispersing chemical signals to conspecifics or nearby male elephants.

The present study addresses two areas of research. The purpose of part one was first, to determine if female Asian elephants …


The Mayfly Newsletter, Peter M. Grant Jan 1999

The Mayfly Newsletter, Peter M. Grant

The Mayfly Newsletter

The Mayfly Newsletter is the official newsletter of the Permanent Committee of the International Conferences on Ephemeroptera.


Microbial Colonization Of The Cloacae Of Nestling Tree Swallows, Tamara K. Mills, Michael P. Lombardo, Patrick A. Thorpe Jan 1999

Microbial Colonization Of The Cloacae Of Nestling Tree Swallows, Tamara K. Mills, Michael P. Lombardo, Patrick A. Thorpe

Peer Reviewed Publications

Microbes have the potential to be important selective forces in many aspects of avian biology. Microbes can affect fitness as a result of either their pathogenic or beneficial effects on host health. Little is known about the chronology of microbial colonization of nestlings or the effects of microbes on fledgling condition. We set out to (1) characterize the time course of microbial colonization of the cloacae of nestling Tree Swallows (Tachycineta bicolor), (2) examine the relationship between cloacal microbes and fledgling condition, and (3) determine if nest mates had similar assemblages of cloacal microbes. We repeatedly measured nestlings …


The Chondrocranium Of The Mexican Burrowing Toad, Rhinophrynus Dorsalis, Charles C. Swart, Rafael O. De Sá Jan 1999

The Chondrocranium Of The Mexican Burrowing Toad, Rhinophrynus Dorsalis, Charles C. Swart, Rafael O. De Sá

Biology Faculty Publications

The chondrocranium of Rhinophrynus dorsalis is described and illustrated. Autapomorphies of R. dorsalis are the presence of the symplectic cartilage and a cartilaginous process on the ascending process of the palatoquadrate. Synapomorphies of Rhinophrynus shared with the Pipidae are: (1) early formation of the lower jaw and (2) presence of a suprarostral plate. Alternative developmental pathways for the formation of the suprarostral plate are considered. Histological data indicates that the suprarostral plate forms from: (1) the early fusion of the cornua trabeculae with the suprarostral cartilages, (2) an anterior growth of the ethmold plate, and (3) subsequent fusion …


Unidad De Los Anfibios Modernos Como Grupo Natural, Rafael O. De Sá Jan 1999

Unidad De Los Anfibios Modernos Como Grupo Natural, Rafael O. De Sá

Biology Faculty Publications

RESUMEN

La monofilia de la infraclase Lissamphibia ha sido cuestionada. Algunos autores sugieren un origen independiente del Orden Gymnophiona basados en la condición compacta (= estegocrotafía) del cráneo de la cecilias. La presente revisión indica la irrelevancia del estegocrotafismo para establecer las relaciones filogenéticas del grupo. Los datos disponibles sugieren: 1) el estegocrotafismo es secundariamente derivado en cecilias, y 2) Lissamphibia representa un grupo monofilético.

SUMMARY

Unity of modern Amphibians as a natural group

The monophyly of Lissamphibia has been previously questioned. Some authors suggested an independent origin of Gymnophiona based on the solid condition (= stegokrotaphy) of the caecilian …


The Mayfly Newsletter, Peter M. Grant Jun 1998

The Mayfly Newsletter, Peter M. Grant

The Mayfly Newsletter

The Mayfly Newsletter is the official newsletter of the Permanent Committee of the International Conferences on Ephemeroptera.


Tapeinosperma Alatum (Myrsinaceae): A Remarkable New Species From Ceram, Diane Holland, P.F. Stevens Jan 1998

Tapeinosperma Alatum (Myrsinaceae): A Remarkable New Species From Ceram, Diane Holland, P.F. Stevens

Biology Department Faculty Works

A new pachycaul species Tapeinosperma alatum D.E. Holland & P.F. Stevens (Myrsinaceae) is described from South Central Ceram. It is characterized by its huge leaves, over 1 m long, and congested, almost Gunnera-like. inflorescence. The distinctive distribution of the Papuasian pachycaul species of Tapeinosperma is briefly compared with that of a number of other unrelated taxa.


Phorbol Ester Activation Of An Nhe-Like Electroneutral Na+ /H+ Antiporter In Isolated E-Cells Of Lobster (Homarus Americanus) Hepatopancreas, Jeff Duerr, Gregory A. Ahearn Jan 1998

Phorbol Ester Activation Of An Nhe-Like Electroneutral Na+ /H+ Antiporter In Isolated E-Cells Of Lobster (Homarus Americanus) Hepatopancreas, Jeff Duerr, Gregory A. Ahearn

Faculty Publications - Department of Biological & Molecular Science

The basolateral membrane of Atlantic lobster (Homarus americanus) epithelium possesses an electroneutral Na+ /H+ antiporter that functionally resembles members of the vertebrate NHE family. Regulatory mechanisms of this antiporter in purified hepatopancreatic E-cell suspensions, produced with a centrifugal elutriation technique, were investigated. Suspensions routinely consisted of greater than 95% E-cells displaying greater than 90% viability. Intracellular pH (pHi) was monitored by loading cells with the fluorescent dye 2´,7´-bis(carboxyethyl)-5,6- carboxyfluorescein (BCECF), and placing suspensions in a spectrofluorometer. Recovery from induced acid-loading was mediated by a Na+ -dependent, dimethylamiloride-sensitive proton efflux. Antiport activation was a sigmoidal function of pHi at values below …


Intraspecific Heterochrony And Life History Evolution: Decoupling Somatic And Sexual Development In A Facultatively Paedomorphic Salamander, Travis J. Ryan, Raymond D. Semlitsch Jan 1998

Intraspecific Heterochrony And Life History Evolution: Decoupling Somatic And Sexual Development In A Facultatively Paedomorphic Salamander, Travis J. Ryan, Raymond D. Semlitsch

Scholarship and Professional Work - LAS

Morphological features such as size and shape are the most common focus in studies of heterochronic change. Frequently, these easily observed and measured features are treated as a major target of selection, potentially ignoring traits more closely related to fitness. We question the primacy of morphological data in studies of heterochrony, and instead suggest that principal sources of fitness, such as life history characteristics, are not only the chief targets of selection, but changes in them may necessitate changes in other (subordinate) elements of the organism. We use an experimental approach to investigate the timing of metamorphosis and maturation in …


Chondrocranial Anatomy And Skeletogenesis In Dendrobates Auratus, Rafael O. De Sá, Shannon Hill Jan 1998

Chondrocranial Anatomy And Skeletogenesis In Dendrobates Auratus, Rafael O. De Sá, Shannon Hill

Biology Faculty Publications

The larval chondrocranium and visceral skeleton of Dendrobates auratus ls described and compared with those of other dendrobatids. Four characters, i.e. lack of fusion between orbital cartilages and otic capsules, wide processus muscularis palatoquadrati, lack of processus pseudopterygoideus, and lack of processus anterolateralis hyalis, represent derived conditions for Dendrobates within Dendrobatidae. Cranial and postcranial ossification sequences are reported for D. auratus and Epipedobates tricolor. Skeletogenesis is earlier in E. tricolor, but the overall pattern of ossification is similar in the two species.


The Mayfly Newsletter, Peter M. Grant Dec 1997

The Mayfly Newsletter, Peter M. Grant

The Mayfly Newsletter

The Mayfly Newsletter is the official newsletter of the Permanent Committee of the International Conferences on Ephemeroptera.


The Mayfly Newsletter, Peter M. Grant Jun 1997

The Mayfly Newsletter, Peter M. Grant

The Mayfly Newsletter

The Mayfly Newsletter is the official newsletter of the Permanent Committee of the International Conferences on Ephemeroptera.


An Analysis Of The Variation Within Cratoxylum Arborescens (Clusiaceae) In Malesia, A.C. Church, P.F. Stevens Jan 1997

An Analysis Of The Variation Within Cratoxylum Arborescens (Clusiaceae) In Malesia, A.C. Church, P.F. Stevens

Biology Department Faculty Works

The variation within the widespread West Malesian species Cratoxylum arborescens (Vahl) Blume was analyzed and three distinctive variants were found. These are recognized formally as varieties, var. arborescens, var. miquelii King, and var. borneense A.C. Church & P.F. Stevens. A key and full descriptions are given. The characters employed to delimit the three taxa are discussed and the selection of varietal rank is justified.


Description Of The Tadpole Of Atelopus Tricolor, E. O. Lavilla, Rafael O. De Sá, Ignacio De La Riva Jan 1997

Description Of The Tadpole Of Atelopus Tricolor, E. O. Lavilla, Rafael O. De Sá, Ignacio De La Riva

Biology Faculty Publications

Tadpoles of Atelopus belong to the gastromyzophorous guild of exotrophic larvae (Altig and Johnston, 1989), and are characterized by the presence of a conspicuous abdominal sucker and an expanded oral disc. The larvae of several Atelopus species have been described previously: A. varius (Starrett, 1967); A. certus, A. ignescens, and A. spumarius (Duellman and Lynch, 1969); A. cruciger (Mebs, 1980); A. flavescens (Lescure, 1981); A. peruensis (Gray and Cannatella, 1985); and A. subornatus (Lynch, 1986). These represent about 15% of the known species in the genus (Frost, 1985; Duellman, 1993). Although Atelopus tricolor was originally described at the beginning of …


Description Of Tadpoles Of Three Species Of Scinax (Anura: Hylidae), Rafael O. De Sá, Rocjard Wassersig, Arturo I. Kehr Jan 1997

Description Of Tadpoles Of Three Species Of Scinax (Anura: Hylidae), Rafael O. De Sá, Rocjard Wassersig, Arturo I. Kehr

Biology Faculty Publications

Larval morphological characteristics have been used to cluster species of Scinax in seven species groups and to support the monophyly of some of these groups. However, our present knowledge of Scinax tadpoles is incomplete; currently, tadpoles of only 21 of the approximately 80 recognized species have been described. Herein, we describe and illustrate the external morphology and oral disc characteristics of larval Scinax berthae, S. nebulosa, and S. boesemani. The presence of a "labial arm" supporting the P3 tooth row in S. boesemani, and its absence from S. nebulosa, is discussed in the light of our limited knowledge of tadpoles …


The Mayfly Newsletter, Peter M. Grant Dec 1996

The Mayfly Newsletter, Peter M. Grant

The Mayfly Newsletter

The Mayfly Newsletter is the official newsletter of the Permanent Committee of the International Conferences on Ephemeroptera.


The Mayfly Newsletter, Peter M. Grant May 1996

The Mayfly Newsletter, Peter M. Grant

The Mayfly Newsletter

The Mayfly Newsletter is the official newsletter of the Permanent Committee of the International Conferences on Ephemeroptera.


Communities Of Cloacal Bacteria In Tree Swallow Families, Michael P. Lombardo, Patrick A. Thorpe, R. Cichewicz, M. Henshaw, C. Millard, C. Steen, T. K. Zeller Jan 1996

Communities Of Cloacal Bacteria In Tree Swallow Families, Michael P. Lombardo, Patrick A. Thorpe, R. Cichewicz, M. Henshaw, C. Millard, C. Steen, T. K. Zeller

Peer Reviewed Publications

Our aim in this study was to survey the communities of bacteria found in the cloacae of adult and nestling Tree Swallows (Tachycineta bicolor), determine if there were familial patterns of prevalence, and determine if there were relationships between bacteria loads and nestling size when 12 days old and fledging success.


Leptodactylus Silvanimbus (Amphibia: Anura: Leptodactylidae): Natural History Notes, Advertisement Call, And Relationships, W. Ronald Heyer, Rafael O. De Sá, James R. Mccranie, Larry David Wilson Jan 1996

Leptodactylus Silvanimbus (Amphibia: Anura: Leptodactylidae): Natural History Notes, Advertisement Call, And Relationships, W. Ronald Heyer, Rafael O. De Sá, James R. Mccranie, Larry David Wilson

Biology Faculty Publications

In July 1995, we visited two of the three previously known localities for Leprodactylus silvanimbus in Departamento de Ocotepeque, Honduras. We found a new breeding site for the species, recorded its advertisement call, and collected and observed its adults and larvae. The purpose of this paper is to present the results of these new findings and to comment on the relationships L. silvanimbus.


Características De La Osificación Craneal En Phyllomedusa Boliviana (Anura: Hylidae), Rafael O. De Sá, E. O. Lavilla Jan 1996

Características De La Osificación Craneal En Phyllomedusa Boliviana (Anura: Hylidae), Rafael O. De Sá, E. O. Lavilla

Biology Faculty Publications

RESUMEN. Dentro de la familia Hylidae disponemos de información sobre las secuencias de osificación craneal para menos del 4.0% de sus miembros. El presente trabajo describe la secuencia de osificación craneal de Phyllomedusa boliviana. El patrón general de osificación es similar a lo reportado para otras especies de la familia, pero existen algunas diferencias importantes tales como la osificación tardía de los próoticos y la osificación premetamórfica de neopalatino, vómer, cuadrado-yugal, pterigoides y columela. El lento desarrollo ulterior de la osificación resulta en juveniles con cráneos extensamente cartilaginosos.

ABSTRACT. Characteristics of the cranial ossification in Phyllomedusa …


Hyla Multifasciata, Rafael O. De Sá Jan 1996

Hyla Multifasciata, Rafael O. De Sá

Biology Faculty Publications

Hyla multifasciata is a medium to large species in the albopunctata species group, adults ranging in size from 42 - 61 mm SVL (mean male SVL = 48 mm, mean female SVL = 53 mm). The head is longer than wide. The snout is rounded in dorsal view, whereas in lateral view it is rounded and protrudes slightly beyond the mandible. The canthus rostralis is rounded and distinct, the loreal region is concave, and the internarial region is convex. The eyes are large, approximately twice the diameter of the tympanum. The tympanum is separated from the eye by a distance …


Captive Environmental Influences On Behavior In Zoo Drills And Mandrills (Mandrillus), A Threatened Genus Of Primate, Erik Terdal Jan 1996

Captive Environmental Influences On Behavior In Zoo Drills And Mandrills (Mandrillus), A Threatened Genus Of Primate, Erik Terdal

Dissertations and Theses

Drills (Mandrillus leucophaeus) are an endangered species of African monkey (Cercopithecidae), and their sole congener the mandrill (Mandrillus sphinx) is vulnerable to extinction. Both species are threatened in the wild by deforestation and hunting.

Drills have a poor record of captive reproduction. Many individuals appear to have behavioral deficiencies which interfere with reproduction. Thus, the zoo population of drills does not serve as a “hedge” against the species’ total extinction: drills are endangered in captivity as well as in the wild. Mandrills, by contrast, reproduce well in captivity. Information on the behavior of mandrills in captivity may help zoo managers …


Morphometric, Isozyme And Random Amplified Polymorphic Dna (Rapd) : Analysis Of Sarotherodon Mossambicus Populations In Java, Indonesia, Yoedono Sovyanhadi Dec 1995

Morphometric, Isozyme And Random Amplified Polymorphic Dna (Rapd) : Analysis Of Sarotherodon Mossambicus Populations In Java, Indonesia, Yoedono Sovyanhadi

Loma Linda University Electronic Theses, Dissertations & Projects

The tilapia fish Sarotherodon mossambicus (Teleostei, Cichlidae) is an important protein source for Indonesians, is a strong competitor with some endemic species and .readily hybridizes with other tilapias. A base line assessment of the present genetic diversity of these populations in Indonesia was conducted to facilitate the management of this species. This study compared the effectiveness of the 3 techniques (morphometric, isozyme and RAPD) in revealing differences within and among 9 Javanese populations. The data were also used to estimate the rate of divergence among the populations.

Morphometric analysis showed significant size and shape differences among the populations. Isozyme and …


The Mayfly Newsletter, Peter M. Grant Nov 1995

The Mayfly Newsletter, Peter M. Grant

The Mayfly Newsletter

The Mayfly Newsletter is the official newsletter of the Permanent Committee of the International Conferences on Ephemeroptera.


The Mayfly Newsletter, Peter M. Grant May 1995

The Mayfly Newsletter, Peter M. Grant

The Mayfly Newsletter

The Mayfly Newsletter is the official newsletter of the Permanent Committee of the International Conferences on Ephemeroptera.


Effect Of Feathers As Nest Insulation On Incubation Behavior And Reproductive Performance Of Tree Swallows (Tachycineta Bicolor), Michael P. Lombardo, Ruth M. Bosman, Christine A. Faro, Stephen G. Houtteman, Timothy S. Kluisza Jan 1995

Effect Of Feathers As Nest Insulation On Incubation Behavior And Reproductive Performance Of Tree Swallows (Tachycineta Bicolor), Michael P. Lombardo, Ruth M. Bosman, Christine A. Faro, Stephen G. Houtteman, Timothy S. Kluisza

Peer Reviewed Publications

Many species of birds line their nests with feathers, presumably because of the insulative qualities of feathers and because feathers may act as a barrier between nest parasites and nestlings. In 1993, we experimentally examined the role of feathers as nest insulation on the incubation behavior, nestling growth, and reproductive performance of Tree Swallows (Tachycineta bicolor) nesting in boxes in western Michigan. There were no significant differences between the incubation rhythms of females with experimental nests (i.e. no feathers) and females with control nests (i.e. with feathers). Nestlings that were reared in control nests had significantly longer right …


Within-Pair Copulations: Are Female Tree Swallows Feathering Their Own Nests?, Michael P. Lombardo Jan 1995

Within-Pair Copulations: Are Female Tree Swallows Feathering Their Own Nests?, Michael P. Lombardo

Peer Reviewed Publications

A variety of hypotheses has been proposed to explain why socially monogamous birds copulate repeatedly with their mates when only a single copulation is necessary to fertilize an entire clutch (Birkhead and Møller 1992, Petrie 1992, Hunter et al. 1993). Petrie (1992) hypothesized that a female should copulate frequently with her mate so as to reduce her mate’s involvement in extrapair copulations. By reducing her mate’s involvement in extrapair copulations, a female may: (1) avoid the transmission of parasites and sexually transmitted diseases (Hamilton 1990); (2) may avoid sperm depletion by her mate; and (3) may monopolize her mate’s paternal …


Hyla Albopunctata, Rafael O. De Sá Jan 1995

Hyla Albopunctata, Rafael O. De Sá

Biology Faculty Publications

Hyla albopunctata is a medium-sized species in the albopunctata group, adults range in size from 42-52 mm SVL (males average 47 mm and females 49 mm). The head is triangular in outline, always longer than wide. The snout is moderately long and acuminate in dorsal view, whereas in lateral view, it is acuminate and protrudes beyond the mandible to form an angle of 45 degrees over the mandible. The canthus rostralis is rounded and distinct, the loreal region is slightly concave, and the internarial region is slightly convex. The eyes are large, approximately twice the diameter of the tympanum. The …