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Full-Text Articles in Biology
Morphological Divergence Of Native And Recently Established Populations Of White Sands Pupfish (Cyprinodon Tularosa), Michael L. Collyer, James M. Novak, Craig A. Stockwell
Morphological Divergence Of Native And Recently Established Populations Of White Sands Pupfish (Cyprinodon Tularosa), Michael L. Collyer, James M. Novak, Craig A. Stockwell
Faculty Research & Creative Activity
We used landmark-based geometric morphometric methods to describe patterns of body shape variation and shape covariation with size among populations of the threatened White Sands Pupfish (Cyprinodon tularosa), a species that occurs in dissimilar aquatic habitats. White Sands Pupfish populations include two genetically distinct, native populations that have been historically isolated in Salt Creek, a saline river, and Malpais Spring, a brackish spring. In addition, two populations were established approximately 30 years before this study by translocation of fish from Salt Creek to Lost River (a saline river) and Mound Spring (a brackish spring). We found significant body shape variation …
High Levels Of Fluctuating Asymmetry In Populations Of Apodemus Flavicollis From The Most Contaminated Areas In Chornobyl, Taras K. Oleksyk, James M. Novak, James R. Purdue, Sergiy P. Gashchak, Michael H. Smith
High Levels Of Fluctuating Asymmetry In Populations Of Apodemus Flavicollis From The Most Contaminated Areas In Chornobyl, Taras K. Oleksyk, James M. Novak, James R. Purdue, Sergiy P. Gashchak, Michael H. Smith
Faculty Research & Creative Activity
Random deviations from the perfect symmetry of normally bilaterally symmetrical characters for an individual with a given genotype occur during individual development due to the influence of multiple environmental factors. Fluctuating asymmetry (FA) is often used as a measure of developmental instability, and can be estimated as the variance of the distribution of differences between the left and right sides. We addressed the question of whether levels of FA were elevated in radioactively contaminated populations living around Chornobyl compared to those in reference populations of the yellow-necked mouse (Apodemus flavicollis). In addition, we studied amounts of directional asymmetry (DA) when …
Problems With Developmental Stability In Two Rodent Species From Chornobyl, Taras K. Oleksyk, Michael H. Smith, Sergiy P. Gashchak, James M. Novak, James R. Purdue
Problems With Developmental Stability In Two Rodent Species From Chornobyl, Taras K. Oleksyk, Michael H. Smith, Sergiy P. Gashchak, James M. Novak, James R. Purdue
Faculty Research & Creative Activity
Changes in developmental patterns are some of the most important effects that may be observed at radioactively contaminated sites like those at Chornobyl. Developmental instability may arise from the interactions between an organism's genotype and its environment and be manifested as deviant morphology. Fluctuating asymmetry (FA) is a measure of deviations from the expected bilateral symmetry of the body. Our objective was to test for differences in FA in two rodent species (Apodemus flavicollis and Clethrionomys glareolus) that live in habitats suirounding the failed Chornobyl reactor. Rodents were collected from four different locations (two contaminated and two reference sites), and …
Evaluation Of Molar Size As A Basis For Distinguishing Wild Boar From Domestic Swine: Employing The Present To Decipher The Past, John J. Mayer, James M. Novak, I. Lehr Brisbin Jr.
Evaluation Of Molar Size As A Basis For Distinguishing Wild Boar From Domestic Swine: Employing The Present To Decipher The Past, John J. Mayer, James M. Novak, I. Lehr Brisbin Jr.
Faculty Research & Creative Activity
No abstract provided.
Morphological Asymmetry In Mammals: Genetics And Homeostasis Reconsidered, James M. Novak, Olin E. Rhodes Jr., Michael H. Smith, Ronald K. Chesser
Morphological Asymmetry In Mammals: Genetics And Homeostasis Reconsidered, James M. Novak, Olin E. Rhodes Jr., Michael H. Smith, Ronald K. Chesser
Faculty Research & Creative Activity
It has been hypothesized that developmental stability is increased at higher levels of genetic variability (heterozygosity) in animals. However, the existence of this relationship is questionable for homeotherms in general and mammals in particular. The difference between the sides of a bilateral character in an individual is a measure of fluctuating asymmetry that can be used as a measure of the developmental stability of mammals. Increased developmental stability should result in a greater degree of similarity between the right and left side of the body even though environmental variability would tend to increase the differences between right and left sides …
Morphological Asymmetry And Interspecific Hybridization: A Case Study Using Hylid Frogs, Trip Lamb, James M. Novak, Diane L. Mahoney
Morphological Asymmetry And Interspecific Hybridization: A Case Study Using Hylid Frogs, Trip Lamb, James M. Novak, Diane L. Mahoney
Faculty Research & Creative Activity
The limited studies addressing developmental stability of interspecific hybrids suggest a positive association between the level of fluctuating asymmetry and 1) the degree of divergence between parental species, and 2) the recency of the contact zone. To evaluate these associations, we examined asymmetry in a recentlyestablished hybrid population of treefrogs (Hyla cinerea and H. gratiosa) that show marked structural gene divergence. Fluctuating asymmetry (FA), directional asymmetry, and antisymmetry were assessed for eight paired osteometric traits in allozymically-defined parental and hybrid categories. FA levels varied considerably among traits. Nonetheless, for any given trait, the hybrid categories did not demonstrate elevated levels …