M.S. Zoology, University of Washington. 1996
Sc. B. Aquatic Biology, Brown University. 1993

Research Interests:

Evolution of marine invertebrates, evolution of development, systematics, functional morphology, paleobiology, life history evolution, and morphological integration.

Current Research:

Marine invertebrates typically develop through a planktonic larval stage. These larvae provide a means of dispersal for animals that are often sedentary during their adult life. However some species develop without going through such a larval stage (direct development) and thus do not have such a high potential for dispersal. This difference in dispersal ability has been shown to result in differences in speciation and extinction rates. I am interested in the causes of differences in development type and their evolutionary consequences.

My research focuses on Crepidula, a genus of sex-changing marine gastropods, with about 50 species. In the Pritzker lab I am sequencing fragments of COI, 16S and 28S genes to determine the relationships of all Crepidula species. These sequences, combined with observations of development, will allow me to test the hypotheses that development type is correlated with rates of molecular evolution and that direct development has evolved multiple times in this group. In addition I plan to examine the association between development type and ecological variables like body size, habitat depth and latitude. This research is supported primarily by grants from the National Geographic Society and the National Science Foundation.

Publications:

Collin, R. 2001. The effects of mode of development on phylogoegraphy and population structure of North Atlantic Crepidula (Gastropoda: Calyptraeidae). Molecular Ecology 10: 2249-2262

Collin, R. 2000. Sex change, reproduction, and development of Crepidula adunca and Crepidula lingulata (Gastropoda: Calyptraeidae). The Veliger 34:24-33.

Collin, R. 2000. Phylogeny of the Crepidula plana (Gastropoda: Calyptraeidae) cryptic species complex in North America. Canadian Journal of Zoology 78:1500-1514.

Collin, R. 1997. Ontogenetic changes in subtle skeletal asymmetries during development of the sand dollar Dendraster excentricus Evolution 51(3): 999-1005.

Collin, R. 1997. Hydrophobic larval shells: another character for higher level systematics of gastropods. Journal of Molluscan Studies. 63: 425-430.

Collin, R. 1997. Increasing effective malacological communication: A commentary on writing descriptions of molluscan development. The Veliger 40(3): 276-277.

Collin, R. 1995. Sex, size, and position: A test of models predicting the size at sex change in the protandrous gastropod Crepidula fornicata. American Naturalist 146(6):815-831.

Collin, R. and C. M. Janis. 1997. Phylogenetic constraints on feeding adaptations: Why there were no suspension-feeding marine reptiles? E. Nichols and J. Calloway eds. Ancient Marine Reptiles. Society of Vertebrate Paleontology symposium on Mesozoic marine reptiles. Academic Press.

Collin, R. and J. Voltzow. 1998. Initiation, calcification, and form of larval "archaeogastropod" shells. Journal of Morphology. 235(1): 77-89.

Collin, R. and J. B. Wise. 1997. Morphology and development of Odostomia columbiana (Gastropoda: Pyramidellidae). Biological Bulletin 192: 243-252.

Current Position:

http://striweb.si.edu/collinlab/