Fitness correlates of sex reversal
Among the wild-caught adults, XX sex-reversed males had similar body
mass as normal males (LME, slope ± SE = 1.47 ± 1.29, t98= 1.15, p = 0.254; Figure 2). However, among the lab-raised animals we
found several signs of reduced fitness and/or increased physiological
stress in the XX sex-reversed males, including reduced body mass,
increased spleen size, and liver abnormalities (see details in
Supporting Information, pages 11-12, Table S5, Figures S6-7). In 2 out
of the 6 individuals that were genetically female but had testes with
normal anatomy, histological analysis revealed oogonia in otherwise
normal testicular tissue (Figure S3), in contrast to the 17 males
dissected in 2016 that all had testes without oogonia. These two
individuals had small testes relative to their body size and age (Figure
S8). The remaining 4 sex-reversed individuals showed completely normal
testicular histology in the examined sections (Figure S3). In those two
individuals that had XX siblings only (possibly sired by an XX male; see
above), testis size was large relative to their body size and age
(Figure S8), and testis histology showed a more mature developmental
stage than in the rest of the histologically examined individuals
(Figure S3).