Biology Projects 2010
Scorpion Responses to Moonlight.
Faculty Mentor - Dr. Carl Kloock
revious experiments have shown that scorpions respond to low levels of ultraviolet (UV) light in the laboratory, but it is not known whether this matters in their natural environment. This summer's REVSUP project will look at the effect of moonlight on scorpion behavior and ask whether scorpions respond to the UV light in moonlight by changing their refuge-seeking behavior. Activities will include collection of scorpions from their natural environment, maintenance of a laboratory scorpion population, building of experimental equipment (including potentially some light carpentry and electronics), videotaping of scorpion behaviors in several contexts and analysis of those tapes. Please note: Scorpions are nocturnal animals, so collection and videotaping must occur at night - thus participants will be expected to work at night for much of this project
Identification of antifungal bacteria from invasive fouling bryozoa of California.
Faculty Mentor - Dr. Antje Lauer
Invasive Bryozoa (= colonial marine filter feeding invertebrates) such as Bugula sp., and Watersipora sp. have outcompeted many native invertebrate species on California's coast. With the loss of diversity of invertebrate marine species at California's coast, the general health of this ecosystem will become out of balance which will have a considerable impact on other organisms as well. Furthermore, we also loose potential sources for interesting metabolites produced by these invertebrates and their associated microorganisms that can be potentially used against human pathogens and cancer. Bryozoan species that possess associations with bacteria are usually among the most frequently encountered fouling bryozoans. Beside of endosymbionts, epibiotic bacterial species on the frontal membrane of Bryozoa might be involved in fighting off other invertebrate larvae and microorganisms, including potential pathogens that could result in overgrowth of the bryozoa or cause disease. For example, antifungal metabolites produced by epibiotic bacteria could prevent fungal overgrowth of bryozoa or an infection by a fungal pathogen. The protective character of epibiotic bacteria is known for other organisms including humans. In this project, we want to isolate and identify bacteria from Bryozoa and test them against different marine fungal species that can be a possible threat to Bryozoa and against some species of dermatophytes that can cause disease in humans. This work will advance our understanding about the adaptation in two invasive fouling Bryozoa and elucidate the role symbiotic microorganisms' play in their extraordinarily successful invasion of California's coast (and worldwide), but also investigates if natural products from these bacteria have a potential of being used in human medicine.
Vascular Transport of California Native Shrubs
Faculty Mentors - Dr. R. Brandon Pratt
Wood, referred to as xylem by scientists, is a globally important commodity that has been important to humans for building material, shelter, and fuel for millennia. In plants, wood makes up the water transport tissue that is crucial for moving water and chemicals throughout the plant body to maintain healthy functioning. Understanding how wood functions not only enables more efficient use of this important resource, but it also helps us understand how plants are adapted to the environment, how ecosystems function, and plant evolution.
Although wood is commercially and physiologically important, many aspects of wood function remain a mystery. Summer research will focus on the physiology of water transport in wood in a ecological context. Sampled species will include some of California's beautiful and rare woody shrubs.
Dr. Pratt's laboratory includes a vibrant and fun loving group that includes undergraduates, Master's students, and post-doctoral scholars.
Genetic Studies on the Endangered Bakersfield Cactus, Opuntia basilaris var. treleasei
Faculty Mentor - Dr. Paul Smith
The Beavertail Cactus, Opuntia basilaris, is a small prickly pear cactus that is distributed throughout the southwest USA, mostly in the Mojave and Colorado Deserts (Fig 1A). The Bakersfield Cactus (Fig 1C), O. basilaris var. treleasei, is an endangered species/variety of O. basilaris (Fig 1C), and is the only native cactus in the Great San Joaquin Valley. The taxonomic status of the endangered Bakersfield Cactus is currently in a state of flux, it has been treated as: (1) a separate distinct species, (2) a susbspecies, and (3) currently as a variety. There are some morphological differences between Bakersfield Cactus and true O. basilaris to support specific status, including pad shape and glochid structure (Bakersfield Cactus possess spines, whereas true O. basilaris do not). This project will utilize modern molecular genetic methods to learn more about the genetic variation between Bakersfield Cactus and true O. basilaris. Specifically, we will determine if there is genetic evidence to support the specific status of the Bakersfield Cactus.
Figure 1. Opuntia basilaris. (A) distribution of O. basilaris proper. (B) True O. basilaris with spineless glochids. (C) Bakersfield Cactus, glochids with spines.
Do bacteria found on the skin of the North American Bullfrog (Rana catesbeiana) play a role in protecting it from the fungal pathogen Batrachochytrium dendrobatidis (Bd)?
Faculty Mentor - Dr. Kathleen Szick-Miranda
This study focuses on the bacterial diversity found on the skin of the Northern American Bullfrog Rana catesbeiana, an invasive species in California that is able to successfully outcompete other native amphibian species. One reason that explains its success is that it is immune to a variety of amphibian diseases including Chydridiomycosis, a skin disease caused by a fungus known as Batrachochytrium dendrobatidis (Bd). Chytridiomycosis is responsible for major amphibian declines worldwide. The reasons why the bullfrog can get infected, but does not succumb to the disease are not known. Recent research suggests that resident skin bacteria can play a role in protecting amphibians against Bd. Our study focuses on the diversity and antifungal ability of the cutaneous bacteria of R. catesbeiana from three different locations in the Southern San Joaquin Valley, CA. Participants in this research project will isolate skin bacteria and test their antifungal potential against Bd. and other potentially pathogenic fungi. In addition, participants will learn the fundamentals of research design, analysis and interpretation. The data collected from this project may have the potential to widely impact global amphibian conservation as well as human health issues by identifying probiotics that can lead to the discovery of potential antibiotics or novel chemotherapeutic compounds in the future.