TY - JOUR

T1 - Independent and adaptive evolution of phenotypic novelties driven by coral symbiosis in barnacle larvae

AU - Dreyer, Niklas

AU - Tsai, Pei Che

AU - Olesen, Jørgen

AU - Kolbasov, Gregory A.

AU - Høeg, Jens T.

AU - Chan, Benny K. K.

N1 - Publisher Copyright: © 2021 The Authors. Evolution © 2021 The Society for the Study of Evolution.

PY - 2022

Y1 - 2022

N2 - The invasion of novel habitats is recognized as a major promotor of adaptive trait evolution in animals. We tested whether similar ecological niches entail independent and adaptive evolution of key phenotypic structures related to larval host invasion in distantly related taxa. We use disparately related clades of coral barnacles as our model system (Acrothoracica: Berndtia and Thoracicalcarea: Pyrgomatidae). We analyze the larval antennular phenotypes and functional morphologies facilitating host invasion. Extensive video recordings show that coral host invasion is carried out exclusively by cypris larvae with spear-shaped antennules. These first exercise a series of complex probing behaviors followed by repeated antennular penetration of the soft host tissues, which subsequently facilitates permanent invasion. Phylogenetic mapping of larval form and function related to niche invasion in 99 species of barnacles (Thecostraca) compellingly shows that the spear phenotype is uniquely associated with corals and penetrative behaviors. These features evolved independently in the two coral barnacle clades and from ancestors with fundamentally different antennular phenotypes. The larval host invasion system in coral barnacles likely evolved adaptively across millions of years for overcoming challenges associated with invading and entering demanding coral hosts.

AB - The invasion of novel habitats is recognized as a major promotor of adaptive trait evolution in animals. We tested whether similar ecological niches entail independent and adaptive evolution of key phenotypic structures related to larval host invasion in distantly related taxa. We use disparately related clades of coral barnacles as our model system (Acrothoracica: Berndtia and Thoracicalcarea: Pyrgomatidae). We analyze the larval antennular phenotypes and functional morphologies facilitating host invasion. Extensive video recordings show that coral host invasion is carried out exclusively by cypris larvae with spear-shaped antennules. These first exercise a series of complex probing behaviors followed by repeated antennular penetration of the soft host tissues, which subsequently facilitates permanent invasion. Phylogenetic mapping of larval form and function related to niche invasion in 99 species of barnacles (Thecostraca) compellingly shows that the spear phenotype is uniquely associated with corals and penetrative behaviors. These features evolved independently in the two coral barnacle clades and from ancestors with fundamentally different antennular phenotypes. The larval host invasion system in coral barnacles likely evolved adaptively across millions of years for overcoming challenges associated with invading and entering demanding coral hosts.

KW - Adaptive host invasion

KW - barnacle phylogeny

KW - coral barnacle

KW - larval phenotypes

U2 - 10.1111/evo.14380

DO - 10.1111/evo.14380

M3 - Journal article

C2 - 34705275

AN - SCOPUS:85121347289

VL - 76

SP - 139

EP - 157

JO - Evolution; international journal of organic evolution

JF - Evolution; international journal of organic evolution

SN - 0014-3820

IS - 1

ER -