Long-term Sabbatical
Chitons are basal marine mollusks with conservative morphology. As such they are important model animals for the study of molluscan evolution and marine animals in general. I propose to expand and synthesize ongoing research on worldwide chiton phylogeny and comparative phylogeography. I will focus on the diverse northern Pacific fauna, especially extending current collaborations with Ryan Kelly. We have already extracted and sequenced gene regions from over 1,800 chitons, representing 90 species and 90 percent of those present in the northeastern Pacific (or 10 percent of worldwide chitons). We propose to further analyze these mitochondrial and nuclear sequences, inferring genealogies within separate northern Pacific chiton clades. Building on recent global studies of chitons, we now have compelling evidence that about 10 northeastern Pacific chiton lineages have each radiated within the northern Pacific, together achieving the greatest disparity of morphology, ecology, and size known anywhere for chitons. Living and fossil chiton evidence suggests these radiations occurred surprisingly recently during Pleistocene climatic fluctuations, accompanied by shifting distributions but without obvious long-lasting blocks to gene flow. Our thorough comparative phylogeographic sampling provides us with tremendous potential for a model case of understanding oceanic speciation and diversification processes. I propose to also build on ongoing combined phylogenetic studies of worldwide chiton morphology and DNA, including ongoing international collaborations. This will improve our resolution of the origin and subsequent dispersal events from the northeastern Pacific "hotspot" of chiton diversity, including its historical relationship to Panamic, northwestern Pacific, Arctic, and northern Atlantic chiton faunas through time.
Chiton phylogeny and comparative phylogeography
| PI(s): | Douglas Eernisse (California State University-Fullerton) |
| Start Date: | 1-Sep-2006 |
| End Date: | 31-May-2007 |
| Keywords: | biodiversity, phylogenetics, comparative methods |
Chitons are basal marine mollusks with conservative morphology. As such they are important model animals for the study of molluscan evolution and marine animals in general. I propose to expand and synthesize ongoing research on worldwide chiton phylogeny and comparative phylogeography. I will focus on the diverse northern Pacific fauna, especially extending current collaborations with Ryan Kelly. We have already extracted and sequenced gene regions from over 1,800 chitons, representing 90 species and 90 percent of those present in the northeastern Pacific (or 10 percent of worldwide chitons). We propose to further analyze these mitochondrial and nuclear sequences, inferring genealogies within separate northern Pacific chiton clades. Building on recent global studies of chitons, we now have compelling evidence that about 10 northeastern Pacific chiton lineages have each radiated within the northern Pacific, together achieving the greatest disparity of morphology, ecology, and size known anywhere for chitons. Living and fossil chiton evidence suggests these radiations occurred surprisingly recently during Pleistocene climatic fluctuations, accompanied by shifting distributions but without obvious long-lasting blocks to gene flow. Our thorough comparative phylogeographic sampling provides us with tremendous potential for a model case of understanding oceanic speciation and diversification processes. I propose to also build on ongoing combined phylogenetic studies of worldwide chiton morphology and DNA, including ongoing international collaborations. This will improve our resolution of the origin and subsequent dispersal events from the northeastern Pacific "hotspot" of chiton diversity, including its historical relationship to Panamic, northwestern Pacific, Arctic, and northern Atlantic chiton faunas through time.Related products
Publications- Polyplacophora (Mollusca) from the San Diego Formation: a remarkable assemblage of fossil chitons from the Pliocene of Southern California Vendrasco, M., Eernisse, D., Powell, C., Fernandez, C. 2012. Polyplacophora (Mollusca) from the San Diego Formation: a remarkable assemblage of fossil chitons from the Pliocene of Southern California. Contributions in Science 520: 15-72.
- Polyplacophora (Mollusca) from the San Diego Formation: a remarkable assemblage of fossil chitons from the Pliocene of Southern California Vendrasco, M., Eernisse, D., Powell, C., Fernandez, C. 2012. Polyplacophora (Mollusca) from the San Diego Formation: a remarkable assemblage of fossil chitons from the Pliocene of Southern California. Contributions in Science 520: 15-72.
- A Chiton Uses Aragonite Lenses to Form Images Daniel I. Speiser, Douglas J. Eernisse and Sönke Johnsen. 2011, A Chiton Uses Aragonite Lenses to Form Images, Current Biology, volume 21, issue 8, pp. 665-670
- Henricia pumila sp. nov.: A brooding seastar (Asteroidea) from the coastal northeastern Pacific Eernisse, D., M. Strathmann, and R. Strathmann (2010). Henricia pumila sp. nov.: A brooding seastar (Asteroidea) from the coastal northeastern Pacific. Zootaxa 2329: 22-36.
- A New Genus And Two New Species Of Multiplacophorans (Mollusca, Polyplacophora, Neoloricata), Mississippian (Chesterian), Indiana Puchalski, S.S., C.C. Johnson, E.G. Kauffman, et al. (2009). A New Genus And Two New Species Of Multiplacophorans (Mollusca, Polyplacophora, Neoloricata), Mississippian (Chesterian), Indiana. Journal Of Paleontology 83(3): 422-430.
- You Say Conchaphila, I Say Lurida: Molecular Evidence For Restricting The Olympia Oyster (Ostrea Lurida Carpenter 1864) To Temperate Western North America Polson, M.P., W.E. Hewson, D.J. Eernisse, et al. (2009). You Say Conchaphila, I Say Lurida: Molecular Evidence For Restricting The Olympia Oyster (Ostrea Lurida Carpenter 1864) To Temperate Western North America. Journal Of Shellfish Research 28(1): 11-21.
- Reconstructing a radiation: the chiton genus Mopalia in the north Pacific Kelly, R. and D. Eernisse (2008). Reconstructing a radiation: the chiton genus Mopalia in the north Pacific. Invertebrate Systematics 22: 17-28.
