The elimination of lower trophic levels following severe habitat
disturbance can trigger new community assembly processes. However,
little is known about how past habitat disturbances have affected
codependent evolution of trophically-linked and closely interacting
taxa. Using genome-wide analysis of a macroalgal community affected by
ancient catastrophic coastal uplift, we track the ecological dynamics of
past co-dispersal and co-diversification among obligate interacting
taxa. Our study reveals rapid and concerted reassembly of an intertidal
community following disturbance. Specifically, hierarchical
co-demographic analyses of multispecies genomic data support synchronous
expansions of four strictly intertidal species in the wake of tectonic
disturbance. These data show that tight algal-epifaunal links underpin
parallel demographic responses across distinct trophic levels. These
results highlight that high-resolution comparative genomic data can
elucidate the strength of obligate ecological interactions, and the
evolutionary dynamics of past co-dispersal and co-diversification in
post-disturbance communities.