August 1, 2013.
Leptasterias spp. are six-rayed sea stars found along the rocky intertidal of the northeast Pacific Alaska to Santa Catalina Island, southern California. In central California, three clades of Leptasterias are found in separate or mixed populations, in diverse habitats that range from shallow pools of seagrass and algae to bare rock exposed to crashing waves. Initial field observations of two clades from different locations suggested that behavioral variation may relate to habitat differences among clades. To measure differences in activity, the righting response was timed at both field sites. As a result of behavioral variation observed in the field, more extensive tests were conducted in the lab. Individual behaviors recorded included: location in tank, response to food cue, aeration and mobile substrate, attachment surface, and contact with other stars. Stars living in sea grass and algae may extend their arms and tube feet to move and collect food. Stars living on rocks and within crevices may use to differentiation their tube feet and arms to conform to the irregularities of the rock surface with a tight suction and feed directly on their prey. The experiments provide measures of behavioral variation among the clades while housed in a common environment, suggesting behavioral variation that may be correlated with genetic differentiation.
Animal Sciences | Biology | Marine Biology | Zoology
C. Sarah Cohen
Romberg Tiburon Center for Environmental Studies (RTC)
This material is based upon work supported by the S.D. Bechtel, Jr. Foundation and by the National Science Foundation under Grant No. 0952013. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the S.D. Bechtel, Jr. Foundation or the National Science Foundation. This project has also been made possible with support of the National Marine Sanctuary Foundation. The STAR program is administered by the Cal Poly Center for Excellence in Science and Mathematics Education (CESaME) on behalf of the California State University (CSU).