title: Cultural transmission of tool use in bottlenose dolphins.
abstract: In Shark Bay, wild bottlenose dolphins (Tursiops sp.) apparently use marine sponges as foraging tools. We demonstrate that genetic and ecological explanations for this behavior are inadequate; thus, "sponging" classifies as the first case of an existing material culture in a marine mammal species. Using mitochondrial DNA analyses, we show that sponging shows an almost exclusive vertical social transmission within a single matriline from mother to female offspring. Moreover, significant genetic relatedness among all adult spongers at the nuclear level indicates very recent coancestry, suggesting that all spongers are descendents of one recent "Sponging Eve." Unlike in apes, tool use in this population is almost exclusively limited to a single matriline that is part of a large albeit open social network of frequently interacting individuals, adding a new dimension to charting cultural phenomena among animals.
authors.affiliation: School of Biological, Earth, and Environmental Sciences, University of New South Wales, Sydney NSW 2052, Australia. michael.kruetzen@aim.unizh.ch
authors.forename: Michael
authors.initials: M
authors.lastname: Krützen
authors.forename: Janet
authors.initials: J
authors.lastname: Mann
authors.forename: Michael R
authors.initials: MR
authors.lastname: Heithaus
authors.forename: Richard C
authors.initials: RC
authors.lastname: Connor
authors.forename: Lars
authors.initials: L
authors.lastname: Bejder
authors.forename: William B
authors.initials: WB
authors.lastname: Sherwin
mesh_terms: D000818:Animals; D003299:Cooperative Behavior; D004289:Dolphins / Q000235:genetics / Q000523:psychology*; D005247:Feeding Behavior / Q000502:physiology*; D005260:Female; D008297:Male; D008957:Models, Genetic