Scientific history, biogeography, and biological traits predict presence of cryptic or overlooked species

Biol Rev Camb Philos Soc. 2023 Dec 4. doi: 10.1111/brv.13034. Online ahead of print.ABSTRACTGenetic data show that many nominal species are composed of more than one biological species, and thus contain cryptic species in the broad sense (including overlooked species). When ignored, cryptic species generate confusion which, beyond biodiversity or vulnerability underestimation, blurs our understanding of ecological and evolutionary processes and may impact the soundness of decisions in conservation or medicine. However, very few hypotheses have been tested about factors that predispose a taxon to contain cryptic or overlooked species. To fill this gap, we surveyed the literature on free-living marine metazoans and built two data sets, one of 187,603 nominal species and another of 83 classes or phyla, to test several hypotheses, correcting for sequence data availability, taxon size and phylogenetic relatedness. We found a strong effect of scientific history: the probability of a taxon containing cryptic species was highest for the earliest described species and varied among time periods potentially consistently with an influence of prevailing scientific theories. The probability of cryptic species being present was also increased for species with large distribution ranges. They were more frequent in the north polar and south polar zones, contradicting previous predictions of more cryptic species in the tropics, and supporting the hypothesis that many cryptic species diverged re...

Source: Biological Reviews of the Cambridge Philosophical Society - December 4, 2023 Category: Biology Authors: Abigail E Cahill Emese Megl écz Anne Chenuil Source Type: research