J�NSSON, K.I.; Lund University, Sweden: A life history perspective to desiccation tolerance Extreme desiccation tolerance, or anhydrobiosis, is a phenotypic trait that has evolved as a response to desiccating conditions imposed by the environment. Periods of anhydrobiosis represent a specific life history stage characterised demographically by a survival function, but such periods may also influence […]

DELPH, Lynda F.*; ASHMAN, Tia-Lynn; Indiana University; University of Pittsburgh: Traits affecting mate acquisition in flowering plants: harmony vs. opposition among traits and sex functions Sexual selection can occur in plants even though individuals do not directly interact via a process known as interaction-independent sexual selection.� For example, if variation exists among individuals in flower […]

MICHIELS, N. K.; BRAUER, B.; University of Muenster, Germany; University of Groningen, Netherlands: The transition from hermaphroditism to dioecy: is sexual conflict important? Hermaphroditism can outcompete gonochorism when mating opportunities are unpredictable and rare, resulting in diminishing returns for the male function. But what happens to hermaphrodites with frequent mating chances? Empirical data from frequently […]

WEEKS, Stephen C.; The University of Akron: The evolution of androdioecy in the ephemeral pool clam shrimp, Eulimnadia texana In androdioecious species, males coexist with hermaphrodites. Androdioecy is rare, found in only a handful of species, and is thought to be a short-lived mechanism for species transitioning from hermaphroditic to gonochoristic reproduction. Most androdioecious species […]

KOENE, J.M.; Vrije Universiteit: Tales of two snails: Sexual selection and sexual conflict in Lymnaea stagnalis and Helix aspersa Sexual selection and sexual conflict have been shown to play key roles in the evolution of species with separate sexes. Experimental evidence is accumulating that this is also true for simultaneous hermaphrodites. For example, many species […]

WEBSTER, Joanne P.; Imperial College Faculty of Medicine: Snails and Schistosomes – Sex and Success. Biomphalaria glabrata are simultaneous hermaphroditic freshwater snails that act as intermediate hosts for the macroparasitic trematode Schistosoma mansoni, the causative agent of schistosomiasis. Heritability and strain-specificity of both snail resistance and susceptibility to schistosome infection have been documented in this […]

PETERSEN, C.W.; College of the Atlantic: Sexual conflict and cooperation in hermaphroditic fishes Mating behavior in simultaneously hermaphroditic seabasses has been often cited as an example of cooperation among unrelated conspecifics. The predominant mating behavior in this group involves egg trading, where individuals reciprocally fertilize parcels of eggs from a partner. Egg trading has been […]

BAUER, R.T.; Univ. Louisiana, Lafayette: Same Sexual System but Variable Sociobiology: Evolution of Protandric Simultaneous Hermaphroditism in Lysmata Shrimps Hermaphroditism is rare in decapod crustaceans except for protandry (male to female sex change) in over 40 caridean shrimp species. In Lysmata spp., individuals go through a male phase (MP) before changing to the female phase […]

GHISELIN, Michael T.; California Academy of Sciences: Sexual Selection in Hermaphrodites: Where Did our Ideas Come From? Interpretations of hermaphroditism have been influenced by the old idea that organisms can be arranged in a series from lower to higher, with human beings at the top, leading toward the angels and God (the scala naturae). The […]

LEONARD, J.L.*; Univ. of California, Santa Cruz: Sexual Selection in Hermaphrodites: What Does It Look Like and Where Do We Find It? Darwin believed that his theory of sexual selection would apply only to animals with sophisticated behavior and sensory systems. Modern emphasis on variance in mating success as an index of the opportunity for […]