Prior to this we had only identified linkage of the 2 sex traits and 1 SSR Spigler et al. The most direct evidence for the important role of the dmrt1 gene has come from the discovery that the sex-determining gene of medaka, dmy originates from a duplicated copy of the autosomal dmrt1 gene [ 44 ].
Blackler AW Germ-cell transfer and sex ratio in Xenopus laevis. Uller T, Helantera H. Population consequences of genetically controlled sex determining mechanisms in Pickering sex reversal. Supplementary Material Additional file 1: Overview of the literature on the effects of temperature on sex ratios and related gene expression in fish.
Gonadal sox9 expression in fish.
The genome sequence of silkworm, Bombyx mori. The fruit fly D. Weird animal genomes and the evolution of vertebrate sex and sex chromosomes. On the other hand, if it has to develop free in water, it becomes a female. These include the Amami spiny rat Tokudaia osimensis and the Tokunoshima spiny rat Tokudaia tokunoshimensis and Sorex araneusa shrew species.
Tissue and sexually dimorphic expression of ovarian and brain aromatase mRNA in the Japanese medaka Oryzias latipes : implications for their preferential roles in ovarian and neural differentiation and development. In addition, genetically controlled sex determining mechanisms in Pickering recent highly interesting study that analyzed sox9b medaka mutants demonstrated that sox9b is not required in genetically controlled sex determining mechanisms in Pickering determination but is indispensable for the proper proliferation and survival of germ cells in both female and male medaka gonads [ ].
Sex determination in multicellular organisms and protistan mating types. However, an experiment in Atlantic silverside showed that TSD could rapidly evolve in response to selection because a balanced sex ratio was reached after 8 to 10 generations by increasing repeatedly the number of individuals with the minority sex in an extreme and constant temperature environment [ ].
These two groups both evolved the ZW system separately, as evidenced by the existence of different sex chromosomal locations.
For example, in the Atlantic silverside, TSD is geography-dependent. In insects, paralogs of transformer tra , a key gene in the sex determination cascade of Drosophila , have evolved as the primary switch in houseflies Musca domestica  , as well as the haplodiploid wasp Nasonia vitripennis  and the honeybee Apis mellifera .
Main article: ZW sex-determination system. Indeed, viable and fertile YY and WW genotypes could repeatedly be produced in some fish and amphibians [ 13 , 67 ]. For example, fig wasp species show: a more extreme sex ratio shifts in more variable environments, when there is stronger selection to adjust sex ratios in response to environmental conditions Herre, ; Herre et al, , and 2 more precise lower variance sex ratios in situations where selection for precise sex ratios stabilizing selection is greater West and Herre,