Campus Units

Ecology, Evolution and Organismal Biology

Document Type

Article

Publication Version

Accepted Manuscript

Publication Date

1-20-2021

Journal or Book Title

Organisms Diversity & Evolution

DOI

10.1007/s13127-021-00482-3

Abstract

Tentacles are fascinating, multifunctional organs found in many aquatic invertebrate groups. In bivalves, tentacles are morphologically diverse, performing protective and sensory roles in taxa from different ecological niches. Such diversity is particularly accentuated in Pteriomorphia, a clade comprising scallops, oysters, file clams, and relatives. However, little is known about the evolution of these organs and their role in bivalve radiation. To test hypotheses of convergent tentacular evolution and a possible association between tentacles and body orientation on the substrate, we first examined tentacle morphology in 108 preserved species representing 15 families across Pteriomorphia. Morphological descriptions of tentacle type (inner mantle fold tentacles – IFT; middle mantle fold tentacles – MFT) and position (marginal and submarginal) are provided, expanding the knowledge of less studied bivalve taxa. Then, we placed the morphological dataset under a molecular phylogenetic framework to estimate ancestral states. IFT had likely four independent origins, while MFT emerged twice independently. After being gained, tentacles have not been lost. In addition, evolution of MFT coincides with transitions in body position with the midsagittal plane parallel to the substrate in the clades of scallops (Pectinida) and oysters (Ostreida). Such a shift could be related to the increase of mantle exposure, favoring the emergence of serially repeated organs, such as tentacles. Altogether, our results support the convergent evolution of tentacles across different taxonomic levels, corroborating the plasticity of the molluscan body and the relevance of evolutionary convergences in the radiation of bivalves.

Comments

This is a manuscript of an article published as Audino, J.A., Serb, J.M. & Marian, J.E.A.R. Untangling the diversity and evolution of tentacles in scallops, oysters, and their relatives (Bivalvia: Pteriomorphia). Org Divers Evol (2021). doi:10.1007/s13127-021-00482-3. Posted with permission.

Copyright Owner

Springer Nature Switzerland AG

Language

en

File Format

application/pdf

Available for download on Thursday, January 20, 2022

Published Version

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