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Full-Text Articles in Life Sciences

Spots Of Adult Male Red-Spotted Newts Are Redder And Brighter Than In Females: Evidence For A Role In Mate Selection?, Andrew K. Davis, Kristine L. Grayson Nov 2008

Spots Of Adult Male Red-Spotted Newts Are Redder And Brighter Than In Females: Evidence For A Role In Mate Selection?, Andrew K. Davis, Kristine L. Grayson

Biology Faculty Publications

As aquatic adults, eastern red-spotted newts (Notophthalmus v. viridescens) are generally green with two rows of dorsal spots, which vary in number between individuals and range in colour from orange to red. The function of these spots is unknown, but it is possible that they serve as sexual ornamentations and we examined this hypothesis by testing for sexual dimorphism in spot characteristics. We used an image analysis approach that has been used previously with this and other amphibian species to compare the number, size and colour – redness (hue score) and brightness – of spots in 100 male …


A New Reproductive Mode In The Genus Melanzophryniscus Gallardo, 1961 (Anura: Bufonidae) With Description Of A New Species From The State Of Paraná, Brazil, José A. Langone, Magno V. Segallo, Marcos Bornschein, Rafael O. De Sá Apr 2008

A New Reproductive Mode In The Genus Melanzophryniscus Gallardo, 1961 (Anura: Bufonidae) With Description Of A New Species From The State Of Paraná, Brazil, José A. Langone, Magno V. Segallo, Marcos Bornschein, Rafael O. De Sá

Biology Faculty Publications

A new species of bufonid toad of the genus Melanophryniscus is described from a mountaintop that is part of the Serra do Mar in the northeastern State of Paraná, Brazil. Melanophryniscus alipioi sp. nov. is distinguished from other known species by its uniformly dark brown dorsal color and a unique breeding site. The new species reproduces in bromeliads, a reproductive mode previously unknown for this genus. This species might be susceptible to current habitat lost.


Exploring The Role Of Iscsua And Suf Operon In Shigella Flexneri Invasion And Resistance To Oxidative Stress, Benjamin R. Lloyd Apr 2008

Exploring The Role Of Iscsua And Suf Operon In Shigella Flexneri Invasion And Resistance To Oxidative Stress, Benjamin R. Lloyd

Honors Theses

Shigella flexneri is a facultative intracellular pathogen capable of causing dysentery, a condition that afflicts many around the world, especially in developing countries. There are several aspects of Shigella pathogenesis that are not well understood, including a number of genetic and cellular changes that allow Shigella to adapt to stresses encountered while invading and replicating within the eukaryotic cytosol. It was the goal of this research to examine the roles of iscSUA and suf, gene systems predicted to encode for iron-sulfur cluster biosynthesis proteins, in Shigella surviving exposure to oxidative stress agents and during Shigella invasion and plaque formation …


Use Of Phylogenetic Stains To Determine The Feeding Preferences Of Microbivorous Soil Nematodes, E. Harlan Michelle Apr 2008

Use Of Phylogenetic Stains To Determine The Feeding Preferences Of Microbivorous Soil Nematodes, E. Harlan Michelle

Honors Theses

Due to their numerous and diverse roles in soil ecological processes – most notably decomposition and nutrient mineralization – nematodes have long been recognized as important biotic indicators of soil health (Ekschmitt et al., 2001; Ritz and Trudgill, 1999). The predominate means of assessing the information that these organisms might contain has been through nematode community analyses, a methodology that seeks to convert the vast amount of data regarding features such as diversity, maturity and richness into a series of indices which can be used to evaluate soil health and make comparisons across samples. Performance of these analyses typically involves …


Characterization Of Sox Family Members In Sponge Stem Cells And During Development, Karen E. Leeds Apr 2008

Characterization Of Sox Family Members In Sponge Stem Cells And During Development, Karen E. Leeds

Honors Theses

Sponges are considered the oldest and most basal part of the metazoan lineage and therefore possess a unique set of gene families that are highly conserved among all animals. One of these gene families is known as Sox transcription factors. Sox genes are known to play important roles in complex animals such as the specification of the primary layers of the body, determination of sex, and most recently induction of induced pluirpotent stem cells (iPS cells) from both human and mouse fibroblasts with the help of three other transcription factors. We have found that two different demosponge species Halichondria bowerbanki …


What Do Students Have To Say About Ecology And Evolution? Using Podcasting To Apply Integrative Biology Themes Across The Tree Of Life, Amy M. Treonis, Malcolm Hill, Theresa Dolson, Sue Mcginnis, Elizabeth Miles Jan 2008

What Do Students Have To Say About Ecology And Evolution? Using Podcasting To Apply Integrative Biology Themes Across The Tree Of Life, Amy M. Treonis, Malcolm Hill, Theresa Dolson, Sue Mcginnis, Elizabeth Miles

Biology Faculty Publications

We describe a versatile podcasting assignment that requires students to (i) review primary and secondary literature relating to an assigned organism with the goal of identifying the main features of its ecology and evolution, (ii) prepare an enhanced podcast about their organism, and (iii) critique peer podcasts. The goal of this assignment is for each student to gain a fuller appreciation for and understanding of biological diversity. This assignment will enhance students' research, technology, and communication skills while reinforcing the main themes of integrative biology.


Is The Amphibian Tree Of Life Really Fatally Flawed?, Darrel R. Frost, Taran Grant, Julian Faivovich, Raoul H. Bain, Alexander Haas, Celio F.B. Haddad, Rafael O. De Sá, Et Al. Jan 2008

Is The Amphibian Tree Of Life Really Fatally Flawed?, Darrel R. Frost, Taran Grant, Julian Faivovich, Raoul H. Bain, Alexander Haas, Celio F.B. Haddad, Rafael O. De Sá, Et Al.

Biology Faculty Publications

Wiens (2007, Q. Rev. Biol. 82, 55–56) recently published a severe critique of Frost et al.'s (2006, Bull. Am. Mus. Nat. Hist. 297, 1–370) monographic study of amphibian systematics, concluding that it is “a disaster” and recommending that readers “simply ignore this study”. Beyond the hyperbole, Wiens raised four general objections that he regarded as “fatal flaws”: (1) the sampling design was insufficient for the generic changes made and taxonomic changes were made without including all type species; (2) the nuclear gene most commonly used in amphibian phylogenetics, RAG-1, was not included, nor were the morphological characters that had justified …


Leptodactylus Cunicularius Sazima And Bokermann Rabbit-Burrow Frog, W. R. Heyer, M. M. Heyer, Rafael O. De Sá Jan 2008

Leptodactylus Cunicularius Sazima And Bokermann Rabbit-Burrow Frog, W. R. Heyer, M. M. Heyer, Rafael O. De Sá

Biology Faculty Publications

Adult Leptodactylus cunicularius are moderately small. The head is longer than wide and the hind limbs are long (Table 1; Heyer and Thompson 2000 provided definitions of adult size and leg length categories for Leptodactylus). Male vocal sacs are internal, not externally expanded. The snout is protruding, not sexually dimorphic. Male forearms are not hypertrophied and males lack asperities on the thumbs and chest. The dorsum is variegated with small, often confluent, spots and blotches. There is a very thin interrupted mid-dorsal light stripe (pinstripe). Usually, there is a noticeable light, irregular, elongate, mid-dorsal blotch in the scapular region. …


The Exploration Of Novel Symbiotic Bacteria That May Have Influential Roles In Sponge Life History, Brittany E. West Jan 2008

The Exploration Of Novel Symbiotic Bacteria That May Have Influential Roles In Sponge Life History, Brittany E. West

Honors Theses

Sponges produce an impressive variety of secondary metabolites that perform a variety of ecological functions. Many marine sponges even harbor diverse carotenoid compounds, an unusual class of secondary metabolites that animals are incapable of producing. Furthermore, sponges serve as hosts to an astonishingly diverse microbial community that can occupy up to sixty percent of a sponge's biomass. Our research ultimately hopes to link microbial species to the production of secondary compounds, like carotenoids, and to assess the ecological role of such compounds and their effect on sponge life history strategy. This study describes the ecological distribution of two species of …


Modulation Of Fast-Inactivating Potassium Channels By Accessory Subunits And Fatty Acids : A Role For Calcium?, Michelle M. Drzewiecki Jan 2008

Modulation Of Fast-Inactivating Potassium Channels By Accessory Subunits And Fatty Acids : A Role For Calcium?, Michelle M. Drzewiecki

Honors Theses

Potassium channel interacting proteins (KChIPs) co-assemble with Kv4 a subunits to form native complexes that encode considerable components of neuronal somatodendritic A- type K+current (Is,J in neurons, and transient outward current (ho) in cardiac myocytes. The binding of KChIPs to the cytoplasmic N-termini of Kv4 a subunits enhances surface expression by facilitating intracellular trafficking, stimulates subunit assembly, and regulates the functional gating properties of Kv4 channels. KChIPs, like many other neuronal calcium sensor proteins, contain four EF-hand calcium binding sites; two of which (EF-3 and 4) have particularly high affinity for calcium. Because Ca2+ is an important signaling molecule for …