(full paper is archived in the Miller Library)
Title: Biogeography of Symbiodinium in Anthopleura
elegantissima on the California coast
Student Author(s): Sanders, Jon
Faculty Advisor(s): Somero, George
Pages: 20
Location: Final Papers Biology 175H
Date: June 2005
Abstract: The algal-cnidarian symbiosis is a useful system for
investigating patterns of selection and adaptation different from
standard single-organism models. Current research, mostly focused on
tropical ecosystems, indicates that the host/symbiont relationship
can be flexible: hosts can house different symbionts under different
conditions. This flexibility may allow for adaptation of the entire
symbiotic system (holosymbiont) rather than the individual players.
However, less is known about the behavior of temperate
algal-cnidarian systems. In this study, I examine the fine scale
dinoflagellate symbiont biogeography in the temperate sea anemone
Anthopleura elegantissima, as first observed by LaJeunesse and
Trench (2000). Restriction Fragment Length Polymorphism (RFLP)
analysis of small subunit (SSU) ribosomal DNA indicates a complex
transition zone from Cape Mendecino (N40º 24', W124º 23')
to Salt Point (N38º 33', W123º 20'), with anemones to the
north harboring Symbiodinium muscatinei and those to the south
co-harboring S. muscatinei and S. californium. S.
californium is present in the north and south of the transition
zone, but absent from the center. A new RFLP signature was found in
anemones from the center of the transition zone, suggesting the
presence of a third dinoflagellate species endemic to that area.