Royal Society Open Science, Journal Year: 2025, Volume and Issue: 12(4)
Published: April 1, 2025
Chondrichthyans (sharks, rays and chimaera) are a fascinating case study through which to examine reproductive biology. While most vertebrate lineages have converged upon either placental viviparity or oviparity, chondrichthyans exhibit unparalleled diversity in mode other aspects of Despite this, our understanding variation this clade remains incomplete. Namely, several 'unusual' traits been repeatedly observed some chondrichthyan taxa, but we little no their adaptive value. Here, I focus on two (facultative parthenogenesis the deposition multiple embryos with separate yolks within single eggcase (MEPE)), theoretically result exponential increases fecundity. discuss theoretical fitness consequences these traits, range species eco-evolutionary contexts they documented major open questions regarding prevalence evolutionary consequences. It appears likely that both facultative MEPE at least taxa ecological contexts. However, additional data needed determine true effect lifetime fecundity, frequency occur, potential population-level effects cues triggers might favour switches from 'typical' sexual reproduction MEPE.
Language: Английский