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

doi:10.1016/j.isci.2020.101652

Two Homogametic Genotypes - One Crayfish: On the Consequences of Intersexuality

iScience. 2020 Oct 6;23(11):101652. doi: 10.1016/j.isci.2020.101652. eCollection 2020 Nov 20.

Authors

Tom Levy¹, Tomer Ventura², Giulio De Leo^{3

4}, Nufar Grinshpan¹, Faiza Amterat Abu Abayed¹, Rivka Manor¹, Amit Savaya¹, Menachem Y Sklarz⁵, Vered Chalifa-Caspi⁵, Dan Mishmar¹, Amir Sagi^{1

5}

Affiliations

¹ Department of Life Sciences, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel.
² GenEcology Research Centre, School of Science and Engineering, University of the Sunshine Coast, Maroochydore, QLD 4558, Australia.
³ Hopkins Marine Station of Stanford University, Pacific Grove, CA 93950, USA.
⁴ Woods Institute for the Environment, Stanford University, Pacific Grove, CA 93950, USA.
⁵ The National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel.

Abstract

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.

Keywords: evolutionary biology; genetics; genotyping; zoology.