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Microclimates associated with environmental and geographic factors directly affect the ability of an organism to survive in a particular area. Survival is affected by: predator/prey abundance, temperature, relative humidity. A group of organisms that are particularly prone to habitat sensitivity are web-building spiders, because building the web commits them to a particular site for a period of time. Anelosimus studiosus is a small (~8 mm) Theridiid spider that exhibits varying degrees of sociality: a subsocial phenotype and a social phenotype. Population densities of A. studiosus vary significantly among seemingly suitable habitats within its range in east Tennessee. I conducted a large-scale survey of east Tennessee lake systems to establish connections between spider presence and geographic features such as aspect, slope and elevation. These geographic features were shown to have a strong impact on overall spider density.

Anelosimus studiosus is a socially polyphenic spider. Individuals can be classified as social/tolerant or solitary/aggressive. These behavioral differences are associated with considerable variation in social structure. Here, we begin to examine the physiological differences that may underlie the behavioral dimorphism in this species and possible implications for the evolution of sociality. Octopamine is a neurotransmitter that has been found to elevate aggression in invertebrates. Serotonin has been shown, in some cases, to interact antagonistically with octopamine. We used High Pressure Liquid Chromatography with Electrochemical Detection to quantify levels of these neurochemicals among adult females from social (multi-female) and solitary (single-female) webs in east Tennessee. A subset of spiders was scored for individual social tendency. We found that higher octopamine levels are associated with a greater degree of aggression and intolerance, both at the individual level and the population level, while higher levels of serotonin are found in multi-female colonies and social individuals.

Quantifying individual differences in behavior and the extent that behavior is influenced by circadian control is of paramount importance in behavioral ecology. In addition, the proximate mechanisms underlying behavior are also critical in order to obtain a more complete picture of how behavior evolves. Biogenic amines (BAs) are simple nitrogenous compounds derived from amino acids and have been consistently and extensively linked to behavior. For this study, we analyzed temporal patterns of BAs in relation to the antipredator (boldness) and aggressive behavior in female Agelenopsis pennsylvanica, a funnel-web spider. Using HPLC-ED, we compared behavioral responses to temporal patterns of octopamine and serotonin, two BAs known to influence behavior in invertebrates. Our results suggest that, while there was a clear diel cycling pattern of both aggression and boldness, BAs do not follow this same pattern, suggesting that oscillations in absolute levels of BAs are not the underpinnings of behavioral oscillations.

Comic book superheroes have become adopted into American popular culture, and yet few have considered why these characters resonate with Americans. The first comic book superhero premiered in 1938 when Superman appeared on the cover of the first issue of Action Comics. For almost seventy years his adventures and the adventures of other costumed heroes have been continually published. Batman soon joined Superman as a popular costumed crime-fighter, and the early 1960s saw another generation of superheroes created that would be embraced in American culture. Among this new group of heroes were Spider-Man and the X-Men, who have proved as popular as Superman and Batman. The never-ending narratives of comic book characters provide a unique opportunity to analyze how superheroes have evolved across the decades to remain relevant for new generations of Americans. Superman, Batman, Spider-Man, and the X-Men are the most popular heroes, not only in comic books, but in other media adaptations. An exploration of why these specific characters have such resonance with Americans will provide insights into American mindsets, ideologies, and philosophies. Furthermore, comic books are uniquely positioned to allow a new historicist reading, as the characters' adventures have been published on a monthly schedule for decades. A consideration of the alterations made in the narratives to reflect the time periods is inherently enlightening.

Spiders produce multiple types of silk that exhibit diverse mechanical properties and biological functions. Most molecular studies of spider silk have focused on fibroins from dragline silk and capture silk, two important silk types involved in the survival of the spider. In this study we have focused on the characterization of egg case silk, a third silk fiber produced by the black widow spider, Latrodectus hesperus , whose DNA coding sequences have not been reported. Based upon solubility differences in 8 M guanidine hydrochloride, it is demonstrated by sodium dodecyl sulfate polyacrylamide gel electrophoresis and silver staining that the egg case silk is relatively complex at the molecular level, containing a large number of proteins with differing molecular weights. Protein components of egg case silk with a size about 100 kDa were obtained by a solubilization time course study, which indicates these proteins are likely to be embedded in the silk filament. Peptides in these 100 kDa proteins were released by tryptic in-gel and in-solution digestion. The peptides were sequenced using a MALDI tandem TOF mass spectrometer. Some of the de novo sequences were confirmed using a linear ion trap mass spectrometer equipped with a nanospray ion source. Combining the peptide sequences obtained, reverse genetics was employed to trace silk genes encoding proteins containing these de novo peptides. Three silk protein coding sequences were successfully discovered, which encode silk proteins named 3B, T1 and ECSP-1, respectively. 3B and T1 show the standard fibroin protein pattern. Amino acid repeat patterns were observed in these two silk clones. But the amino acid compositions of 3B and T1 show differences with the total amino acid composition of egg case silk, and also, the peptide sequences cannot be found in the primary amino acid sequences of 3B and T1. ECSP-1 protein represents one of the egg case silk proteins with a size of about 100 kDa. A number of peptide sequences obtained by mass spectrometric de novo sequencing were successfully located in ECSP-1's primary amino acid sequence. Sequence analysis demonstrates ECSP-1 represents a new class of silk proteins, with fibroin-like properties. The expression pattern of ecsp-1 is largely restricted to the tubuliform gland inside of the L. hesperus spider, with lower levels detected in the major and minor ampullate glands, which also confirms the identity of ECSP-1. It is also demonstrated that ECSP-1 assembles into higher aggregate structures through the formation of disulfide bonds. Peptide sequences from silk proteins from the Tarantula spider Grammostola rosea were also obtained. These sequences will be beneficial in obtaining genes encoding the silk from this spider species.

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