Data for: Biomechanical adaptations enable phoretic mite species to occupy distinct spatial niches on host burying beetles

Niche theory predicts that ecologically similar species coexist by
minimising interspecific competition through niche partitioning. Therefore
understanding the mechanisms of niche partitioning is essential for
predicting interactions and coexistence between competing organisms. Here
we study two phoretic mite species, Poecilochirus carabi, and Macrocheles
nataliae that coexist on the same host-burying beetle Nicrophorus
vespilloides and use it to ‘hitchhike’ between reproductive sites. Field
observations revealed clear spatial partitioning between species in
distinct host body parts. P. carabi preferred the ventral side of the
thorax, whereas M. nataliae were exclusively found ventrally at the hairy
base of the abdomen. Experimental manipulations of mite density showed
that each species preferred these body parts, largely regardless of the
density of the other mite species on the host beetle. Force measurements
indicated that this spatial distribution is mediated by biomechanical
adaptations, because each mite species required more force to be removed
from their preferred location on the beetle. While P. carabi attached with
large adhesive pads to the smooth thorax cuticle, M. nataliae gripped
abdominal setae with their chelicerae. Our results show that specialist
biomechanical adaptations for attachment can mediate spatial niche
partitioning among species sharing the same host.