Meeting Abstract
Sea cucumbers are perhaps the most morphologically derived echinoderm; they possess a worm-like body plan, which sharply juxtaposes the pentaradial symmetry and armored body of other echinoderms. The group has evolved bizarre specializations such as anal suspension feeding, evisceration, sticky Cuvierian tubules that entangle attackers, and a “melting” body wall. Sea cucumbers are ubiquitous throughout all marine landscapes and include >1700 species in 25 families. Despite their diversity, abundance in the marine ecosystems, and economical importance as food, our understanding of their evolutionary history is limited. Here, we present a phylogenomic analysis of Holothuroidea using 9 unpublished and 16 published transcriptomes. Our analysis pipeline includes transcriptome-assembly with Trinity, orthology assignment with OrthoFinder, and alignment construction using MAFFT and Gblocks. We conduct both concatenated and coalescent-based phylogenomic reconstruction. We estimated clade divergence in BEAST and performed an ancestral state reconstruction analysis on 12 discrete traits using the Phytools package in R. This study provides an important initial framework that will allow us to further explore the evolution and biodiversity of this ecologically and economically important group of animals.
