Data from: Commensal associations and benthic habitats shape macroevolution of the bivalve clade Galeommatoidea

The great diversity of marine life has been shaped by the interplay
between abiotic and biotic factors. Among different biotic interactions,
symbiosis is an important yet less studied phenomenon. Here, we tested how
symbiotic associations affected marine diversification, using the bivalve
superfamily Galeommatoidea as a study system. This superfamily contains
large numbers of obligate commensal as well as free-living species and is
therefore amenable to comparative approaches. We constructed a global
molecular phylogeny of Galeommatoidea and compared macroevolutionary
patterns between free-living and commensal lineages. Our analyses inferred
that commensalism/sediment-dwelling is likely to be the ancestral
condition of Galeommatoidea and that secondary invasions of hard-bottom
habitats linked to the loss of commensalism. One major clade containing
most of the free-living species exhibits a 2–4 times higher
diversification rate than that of the commensals, likely driven by
frequent niche partitioning in highly heterogeneous hard-bottom habitats.
However, commensal clades show much higher within-clade morphological
disparity, likely promoted by their intimate associations with diverse
hosts. Our study highlights the importance of interactions between
different ecological factors in shaping marine macroevolution and that
biotic factors cannot be ignored if we wish to fully understand processes
that generate marine biodiversity.