Two Homogametic Genotypes – One Crayfish: On the Consequences of Intersexuality
Tom Levy,
Tomer Ventura,
Giulio De Leo,
Nufar Grinshpan,
Faiza Amterat Abu Abayed,
Rivka Manor,
Amit Savaya,
Menachem Y. Sklarz,
Vered Chalifa-Caspi,
Dan Mishmar,
Amir Sagi
Affiliations
Tom Levy
Department of Life Sciences, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
Tomer Ventura
GenEcology Research Centre, School of Science and Engineering, University of the Sunshine Coast, Maroochydore, QLD 4558, Australia
Giulio De Leo
Hopkins Marine Station of Stanford University, Pacific Grove, CA 93950, USA; Woods Institute for the Environment, Stanford University, Pacific Grove, CA 93950, USA
Nufar Grinshpan
Department of Life Sciences, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
Faiza Amterat Abu Abayed
Department of Life Sciences, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
Rivka Manor
Department of Life Sciences, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
Amit Savaya
Department of Life Sciences, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
Menachem Y. Sklarz
The National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
Vered Chalifa-Caspi
The National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
Dan Mishmar
Department of Life Sciences, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
Amir Sagi
Department of Life Sciences, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel; The National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel; Corresponding author
Summary: In the Australian redclaw crayfish, Cherax quadricarinatus (WZ/ZZ system), intersexuals, although exhibiting both male and female gonopores, are functional males bearing a female genotype (WZ males). Therefore, the occurrence of the unusual homogametic WW females in nature is plausible. We developed W/Z genomic sex markers and used them to investigate the genotypic structure of experimental and native C. quadricarinatus populations in Australia. We discovered, for the first time, the natural occurrence of WW females in crustacean populations. By modeling population dynamics, we found that intersexuals contribute to the growth rate of crayfish populations in the short term. Given the vastly fragmented C. quadricarinatus habitat, which is characterized by drought-flood cycles, we speculate that intersexuals contribute to the fitness of this species since they lead to occasional increment in the population growth rate which potentially supports crayfish population restoration and establishment under extinction threats or colonization events.
