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Paula Mikkelsen Paleontological Research Institution, Ithaca, NY. Bivalvia Factoids. 2 nd largest molluscan class, ~ 20,000 extant species 100+ extant families Cambrian origin, excellent fossil record filter feeders to carnivores; 1 mm to giant clam
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Paula Mikkelsen Paleontological Research Institution, Ithaca, NY
Bivalvia Factoids • 2nd largest molluscan class, ~ 20,000 extant species • 100+ extant families • Cambrian origin, excellent fossil record • filter feeders to carnivores; 1 mm to giant clam • often dominant biomass in aquatic habitats • key part of world fisheries & aquaculture • important ecological and economic threat species • endangered freshwater taxa Zebra mussels Ship worms Freshwater mussels
Morphological Diversity Mikkelsen & Bieler (2007) Princeton University Press
Long research history • Conflicting single-character classifications • Hinges • Adductor muscles • Siphons • Ctenidia • Ciliation • Stomachs • Early numerical approaches (Purchon 1978)
Steps toward a synthesis Johnston & Haggart (1998) Harper et al. (2000) Taylor (1996) Bieler (2006)
Conflicting hypotheses Alternative hypotheses of higher bivalve relationships based on neontological (A, B, C, D), paleontological (E), molecular (G) and combined morphology + molecular evidence (F)
“Bivatol” research goals • Reconstruct phylogenetic relationships for representatives of all 100+ families based on a combination of shell, soft-anatomy, and molecular characters. • Explore new or previously underutilized anatomical and ultra-structural characters (stomach, gills, sperm, mantle), and a suite of new nuclear protein-coding genes never before used for bivalves. • Estimate the time origin of the major bivalve clades based on molecular sequence and fossil data.
John Taylor (BMNH) Sarah Chicone (PRI) John Zardus (Citadel) Brian Gollands (PRI) Dan Graf (ANSP) Gerhard Haszprunar (Munich) Liz Harper (U Cambr.) Tom Waller (NMNH) Protostome AToL Treatise on Invertebrate Paleontology Ellen Strong (NMNH) Rob Ross (PRI) John Healy (U Qld) Deidre Gonsalves-Jackson (VWC) ToLWeb Tim Collins (FIU) Gonzalo Giribet (MCZ) Paula Mikkelsen (PRI) Rüdiger Bieler (FMNH)
Morphology & Coordination Rüdiger Bieler –gills + veneroids Ellen Strong – stomachs Liz Harper – anomalos John Taylor – shell + lucinoids Tom Waller – paleo +pectinoids Gerhard Haszprunar – mantle John Healy – sperm Outreach Paula Mikkelsen Rob Ross – informal education Sarah Chicone – evolution exhibit Deirdre Gonsalves-Jackson – undergrad curriculum Brian Gollands –webmaster / IT Molecules Gonzalo Giribet Tim Collins – heterodonts John Zardus – protobranchs + development Dan Graf – unionoids Character masters Clade masters
Outreach Component • Teaching Evolution using Bivalves • Teacher development resource (K-12) • Undergraduate curriculum (undergrad) • Museum exhibit (public) • Website – “one-stop shop” for bivalve info (public +)
Teacher-Friendly Guideto Evolution using Bivalves Teacher-Friendly Guideto Evolution using Bivalves • resource for teaching essential evolutionary concepts using familiar objects • online + print-on-demand • emphasis on interactive online components • emulates PRI’s popular TFG to Geology
Evolution on the Half-Shell: The Exhibit • small footprint (1200-1500 ft2) • relatively small rental fee • modular design • family-friendly interactives • link to ongoing Bivatol research • to open in 2011 • diversity • fossil record • characters • phylogenetics • patterns of change • evolution continues
Currentstatus • Target taxa (283) & and short-term subset (80) • Preservation protocols • Specimen tracking & collections support in place • Student/postdoc recruiting underway • Outreach advisory board formed • Project server & webmaster in place • Website http://www.bivatol.org • Specimen acquisition underway