purcc 2012 - University of the Pacific

Poster Session Abstracts
states that females who have pups are more
aggressive towards non-filial pups than are
females without pups. The approach to sampling
will be done through focal sampling female
elephant seals with and without pups once an
interaction with a non-filial pup presents itself.
By sampling each female separately for ten
minute intervals, the data can be used to quantify
the amount of times a female exhibits aggressive
behavior. Preliminary findings show that
females who have pups are more prone to being
aggressive towards non-filial pups.
Behavioral thermoregulation of northern
elephant seal (Mirounga angustirostris)
adults and pups in a breeding colony at
Piedras Blancas, California
Patrick Kang, Jaeyoung Lee, Mike Trinh,
Pauline Montamayor, Christopher Nguyen
Faculty Mentor: Richard Tenaza
Our study tested the hypothesis that the Northern
elephant seal (NES) Mirounga angustirostris
uses coloration for thermoregulation on land.
The NES comes ashore every winter to breed
and—being adapted to living in cold seas for
most of the year—on shore they may be faced
with over-heating from higher temperatures and
direct solar radiation. Their large size and thick
blubber give adult NES’s low surface area to
volume ratios and a layer of thermal insulation
which are advantageous for conserving heat in
cold seas but disadvantageous for dissipating it
on land. However, they are very dark on the
back and pale beneath, which could allow them
to absorb or reflect heat by adjusting orientation
to the sun. Pups are born with no blubber but are
uniformly black, which could allow them to
absorb heat from the sun over the entire body
surface. We found that pups did tend to stay
exposed to sunlight in cooler hours and shaded
by their mothers’ shadows in warmer ones. In
adults we found that females exposed their
reflective bellies to the sun more than males at
all times and that both sexes were significantly
more likely to orient the belly toward the sun
during warmer hours compared to cooler ones.
Fluctuations and Sex Differences in Food
Consumption Relative to Molting in
Magellanic Pegnuins (Spheniscus
magellanicus) at San Francisco Zoo
Lisa Keikoan, Nick Le
Faculty Mentor: Richard Tenaza
Our objective was to measure food intake of
adult Magellanic penguins as they fatten up
before molting, fast while molting, and regain
condition afterwards. In late summer and early
fall every year Magellanic penguins shed all their
old feathers and grow new ones. Unable to enter
the water without mature feathers for insulation
penguins fast while molting, and to survive the
fast and grow new feathers they build up fat
stores beforehand. Using data from San
Francisco Zoo, we analyzed fish consumption of
29 female and 26 male penguins for 60 days
before the onset of molt and 40 days after. Data
were standardized for analysis by designating the
first day of molt Day Zero for every bird. Food
intake started increasing noticeably 50 days
before molt began, doubled—going from 200 to
400 g—over the next 30 days, and then more
than doubled again in the following 20 days.
While Magellanic penguins in the wild would
not eat at all while molting, at the zoo they did
but mean daily consumption dropped to 50 g for
both sexes. Molt took 21 days, following which
food consumption increased sharply,
quadrupling over the next 20 days for both sexes,
and then beginning to level off.
Rad51 Paralogs and Complexes – A
Study of Protein Function and
Interactions
Amber Overgard, Daniel Kee Lu
Faculty Mentor: Joanna Albala
Double-strand breaks in DNA have potential to
result in cancer. Currently, there are two methods
known for repairing such breaks and maintaining
genome integrity. These are non-homologous
end-joining (NHEJ) and homologous
recombination repair (HRR). HRR is
accomplished through the use of homologous
DNA strands, one strand acting as a template to
repair the other strand. A key protein in the
strand exchange and homologous pairing used
during HRR is Rad51. Presently, there are five
human proteins with homology to Rad51, these
paralogs are Rad51B, Rad51C, Rad51D, Xrcc2,
and Xrcc3. Loss of these protein functions leads
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