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Bracketing phenogenotypic limits of mammalian hybridization.

ABSTRACT: An increasing number of mammalian species have been shown to have a history of hybridization and introgression based on genetic analyses. Only relatively few fossils, however, preserve genetic material, and morphology must be used to identify the species and determine whether morphologically intermediate fossils could represent hybrids. Because dental and cranial fossils are typically the key body parts studied in mammalian palaeontology, here we bracket the potential for phenotypically extreme hybridizations by examining uniquely preserved cranio-dental material of a captive hybrid between grey and ringed seals. We analysed how distinct these species are genetically and morphologically, how easy it is to identify the hybrids using morphology and whether comparable hybridizations happen in the wild. We show that the genetic distance between these species is more than twice the modern human-Neanderthal distance, but still within that of morphologically similar species pairs known to hybridize. By contrast, morphological and developmental analyses show grey and ringed seals to be highly disparate, and that the hybrid is a predictable intermediate. Genetic analyses of the parent populations reveal introgression in the wild, suggesting that grey-ringed seal hybridization is not limited to captivity. Taken together, we postulate that there is considerable potential for mammalian hybridization between phenotypically disparate taxa.

SUBMITTER: Savriama Y

PROVIDER: S-EPMC6281900 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

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Bracketing phenogenotypic limits of mammalian hybridization.

Savriama Yoland Y Valtonen Mia M Kammonen Juhana I JI Rastas Pasi P Smolander Olli-Pekka OP Lyyski Annina A Häkkinen Teemu J TJ Corfe Ian J IJ Gerber Sylvain S Salazar-Ciudad Isaac I Paulin Lars L Holm Liisa L Löytynoja Ari A Auvinen Petri P Jernvall Jukka J

Royal Society open science 20181128 11

An increasing number of mammalian species have been shown to have a history of hybridization and introgression based on genetic analyses. Only relatively few fossils, however, preserve genetic material, and morphology must be used to identify the species and determine whether morphologically intermediate fossils could represent hybrids. Because dental and cranial fossils are typically the key body parts studied in mammalian palaeontology, here we bracket the potential for phenotypically extreme ...[more]

PMID: 30564397

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Bracketing phenogenotypic limits of mammalian hybridization.

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Bracketing phenogenotypic limits of mammalian hybridization.

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