title: Ancient androdioecy in the freshwater crustacean Eulimnadia.
abstract: Among the variety of reproductive mechanisms exhibited by living systems, one permutation--androdioecy (mixtures of males and hermaphrodites)--is distinguished by its rarity. Models of mating system evolution predict that androdioecy should be a brief stage between hermaphroditism and dioecy (separate males and females), or vice versa. Herein we report evidence of widespread and ancient androdioecy in crustaceans in the genus Eulimnadia, based on observations of over 33,000 shrimp from 36 locations from every continent except Antarctica. Using phylogenetic, biogeographical and palaeontological evidence, we infer that androdioecy in Eulimnadia has persisted for 24-180 million years and has been maintained through multiple speciation events. These results suggest that androdioecy is a highly successful aspect of the life history of these freshwater crustaceans, and has persisted for orders of magnitude longer than predicted by current models of this rare breeding system.
authors.affiliation: Department of Biology, The University of Akron, Akron, OH 44325-3908, USA. scw@uakron.edu
authors.forename: Stephen C
authors.initials: SC
authors.lastname: Weeks
authors.forename: Thomas F
authors.initials: TF
authors.lastname: Sanderson
authors.forename: Sadie K
authors.initials: SK
authors.lastname: Reed
authors.forename: Magdalena
authors.initials: M
authors.lastname: Zofkova
authors.forename: Brenton
authors.initials: B
authors.lastname: Knott
authors.forename: Usha
authors.initials: U
authors.lastname: Balaraman
authors.forename: Guido
authors.initials: G
authors.lastname: Pereira
authors.forename: Diana M
authors.initials: DM
authors.lastname: Senyo
authors.forename: Walter R
authors.initials: WR
authors.lastname: Hoeh
mesh_terms: D000818:Animals; D001483:Base Sequence; D005075:Biological Evolution; D003445:Crustacea / Q000235:genetics* / Q000502:physiology; D004247:DNA / Q000737:chemistry / Q000235:genetics; D012734:Disorders of Sex Development / Q000235:genetics*; D005260:Female; D008297:Male; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D012339:RNA, Ribosomal, 28S / Q000737:chemistry / Q000235:genetics; D016415:Sequence Alignment
chemical_list: D012339:RNA, Ribosomal, 28S; D004247:DNA