SEXUAL SPECIES ARE SEPARATED BY LARGER GENETIC GAPS THAN ASEXUAL SPECIES IN ROTIFERS

摘要: Why organisms diversify into discrete species instead of showing a continuum genotypic and phenotypic forms is an important yet rarely studied question in speciation biology. Does discreteness come from adaptation to fill niches or interspecific gaps generated by reproductive isolation? We investigate the importance isolation comparing genetic discreteness, terms intra- variation, between facultatively sexual monogonont rotifers obligately asexual bdelloid rotifers. calculated age (phylogenetic distance) average pairwise distance (raw within among evolutionarily significant units diversity six clades seven sampled for 4211 individuals total. find that are more than with respect divergence but exhibit similar levels intraspecific variation (species cohesiveness). This pattern arises because bdelloids have diversified clusters at faster net rate monogononts. Although sampling biases differences ecology independent sexuality might also affect these patterns, results consistent hypothesis less their diversification does not depend on evolution isolation.