Data from: Colonize, radiate, decline: unraveling the dynamics of island community assembly with Fijian trap-jaw ants

The study of island community assembly has been fertile ground for
developing and testing theoretical ideas in ecology and
evolution.  The eco-evolutionary trajectory of lineages after
colonization has been a particular interest, as this is a key component of
understanding community assembly.  In this system, existing ideas
such as the taxon cycle posit that lineages pass through a regular
sequence of eco-evolutionary changes after colonization, with lineages
shifting toward reduced dispersal ability, increased ecological
specialization, and declines in abundance. However, these predictions have
historically been difficult to test. Here, we integrate phylogenomics,
population genomics, and x-ray microtomography/3D morphometrics, to test
hypotheses for whether the ecomorphological diversity of trap-jaw ants
(Strumigenys) in the Fijian archipelago is assembled primarily through
colonization or post-colonization radiation, and whether species show
ecological shifts toward niche specialization, toward upland habitats, and
decline in abundance after colonization. We infer that most Fijian endemic
Strumigenys evolved in situ from a single colonization and have
diversified to fill a large fraction of global morphospace occupied by the
genus. Within this adaptive radiation, lineages trend to different degrees
toward high elevation, reduced dispersal ability, and demographic decline,
and we find no evidence of repeated colonization that displaces the
initial radiation.  Overall these results are only partially
consistent with taxon cycle and associated ideas, while highlighting the
potential role of priority effects in assembling island communities.