TY - JOUR

T1 - The tempo and mode of barnacle evolution

AU - Pérez-Losada, Marcos

AU - Harp, Margaret

AU - Høeg, Jens T

AU - Achituv, Yair

AU - Jones, Diana

AU - Watanabe, Hiromi

AU - Crandall, Keith A

N1 - Keywords: Animals; Cell Nucleus; Evolution; Phylogeny; Sequence Analysis, DNA; Thoracica

PY - 2008

Y1 - 2008

N2 - Previous phylogenetic attempts at resolving barnacle evolutionary relationships are few and have relied on limited taxon sampling. Here we combine DNA sequences from three nuclear genes (18S, 28S and H3) and 44 morphological characters collected from 76 thoracican (ingroup) and 15 rhizocephalan (outgroup) species representing almost all the Thoracica families to assess the tempo and mode of barnacle evolution. Using phylogenetic methods of maximum parsimony, maximum likelihood, and Bayesian inference and 14 fossil calibrations, we found that: (1) Iblomorpha form a monophyletic group; (2) pedunculated barnacles without shell plates (Heteralepadomorpha) are not ancestral, but have evolved, at least twice, from plated forms; (3) the ontogenetic pattern with 5-->6-->8-->12+ plates does not reflect Thoracica shell evolution; (4) the traditional asymmetric barnacles (Verrucidae) and the Balanomorpha are each monophyletic and together they form a monophyletic group; (5) asymmetry and loss of a peduncle have evolved twice in the Thoracica, resulting in neither the Verrucomorpha nor the Sessilia forming monophyletic groups in their present definitions; (6) the Scalpellomorpha are not monophyletic; (7) the Thoracica suborders evolved since the Early Carboniferous (340mya) with the final radiation of the Sessilia in the Upper Jurassic (147mya). These results, therefore, reject many of the underlying hypotheses about character evolution in the Cirripedia Thoracica, stimulate a variety of new thoughts on thoracican radiation, and suggest the need for a major rearrangement in thoracican classification based on estimated phylogenetic relationships.

AB - Previous phylogenetic attempts at resolving barnacle evolutionary relationships are few and have relied on limited taxon sampling. Here we combine DNA sequences from three nuclear genes (18S, 28S and H3) and 44 morphological characters collected from 76 thoracican (ingroup) and 15 rhizocephalan (outgroup) species representing almost all the Thoracica families to assess the tempo and mode of barnacle evolution. Using phylogenetic methods of maximum parsimony, maximum likelihood, and Bayesian inference and 14 fossil calibrations, we found that: (1) Iblomorpha form a monophyletic group; (2) pedunculated barnacles without shell plates (Heteralepadomorpha) are not ancestral, but have evolved, at least twice, from plated forms; (3) the ontogenetic pattern with 5-->6-->8-->12+ plates does not reflect Thoracica shell evolution; (4) the traditional asymmetric barnacles (Verrucidae) and the Balanomorpha are each monophyletic and together they form a monophyletic group; (5) asymmetry and loss of a peduncle have evolved twice in the Thoracica, resulting in neither the Verrucomorpha nor the Sessilia forming monophyletic groups in their present definitions; (6) the Scalpellomorpha are not monophyletic; (7) the Thoracica suborders evolved since the Early Carboniferous (340mya) with the final radiation of the Sessilia in the Upper Jurassic (147mya). These results, therefore, reject many of the underlying hypotheses about character evolution in the Cirripedia Thoracica, stimulate a variety of new thoughts on thoracican radiation, and suggest the need for a major rearrangement in thoracican classification based on estimated phylogenetic relationships.

U2 - 10.1016/j.ympev.2007.10.004

DO - 10.1016/j.ympev.2007.10.004

M3 - Journal article

C2 - 18032070

VL - 46

SP - 328

EP - 346

JO - Molecular Phylogenetics and Evolution

JF - Molecular Phylogenetics and Evolution

SN - 1055-7903

IS - 1

ER -