caa a22 4500 445892722 CHVBK 20180317145621.0 cr unu---uuuuu 170323e20110301xx s 000 0 eng 10.1007/s10750-010-0517-z doi (NATIONALLICENCE)springer-10.1007/s10750-010-0517-z Analysing threshold effects in the sexual dynamics of cyclically parthenogenetic rotifer populations [Elektronische Daten] [M. Serra, H. Smith, J. Weitz, T. Snell] Sex in some cyclically parthenogenetic rotifers is triggered when a threshold population density is achieved. In Brachionus, accumulation of a mixis-inducing protein (MIP) that the rotifers excrete into the medium is the proximal signal. Models explicitly accounting for MIP dynamics suggest that either (1) a positive feedback of MIP concentration on MIP production or (2) a switching relationship between the proportion of sexual females and MIP concentration is needed to produce a threshold response of mixis to population density. In order to examine both possibilities, experiments were conducted to estimate the sexual response to a dilution series of medium containing the MIP. The resulting sexual response patterns are consistent with the existence of a threshold response of mixis, but are insufficient to reject one hypothesized mechanism for the threshold response in favor of the other. However, the observed smooth increase of sexual offspring with MIP concentration is consistent with the hypothesis of positive feedback on MIP production, and deserves further investigation. Springer Science+Business Media B.V., 2010 Mixis threshold nationallicence Rotifera nationallicence Dynamic models nationallicence Quorum sensing nationallicence Positive feedback nationallicence Serra M. Institute Cavanilles of Biodiversity and Evolutionary Biology, University of Valencia, Valencia, Spain aut Smith H. School of Biology, Georgia Institute of Technology, Atlanta, GA, USA aut Weitz J. School of Biology, Georgia Institute of Technology, Atlanta, GA, USA aut Snell T. School of Biology, Georgia Institute of Technology, Atlanta, GA, USA aut Hydrobiologia Springer Netherlands 662/1(2011-03-01), 121-130 0018-8158 662:1<121 2011 662 10750 https://doi.org/10.1007/s10750-010-0517-z text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10750-010-0517-z text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Serra M. Institute Cavanilles of Biodiversity and Evolutionary Biology, University of Valencia, Valencia, Spain aut NATIONALLICENCE 700 1- Smith H. School of Biology, Georgia Institute of Technology, Atlanta, GA, USA aut NATIONALLICENCE 700 1- Weitz J. School of Biology, Georgia Institute of Technology, Atlanta, GA, USA aut NATIONALLICENCE 700 1- Snell T. School of Biology, Georgia Institute of Technology, Atlanta, GA, USA aut NATIONALLICENCE 773 0- Hydrobiologia Springer Netherlands 662/1(2011-03-01), 121-130 0018-8158 662:1<121 2011 662 10750 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer