Data from: Big-hearted invaders- the impacts of range expansion and parasite infection on heart mass in cane toads

The invasion of cane toads (Rhinella marina) across tropical Australia has
resulted in the rapid evolution of traits that enable higher rates of
dispersal and that enable toads to adapt to hot, dry climates. In anurans,
a larger heart facilitates both locomotor activity and desiccation
tolerance. Heart size is also often affected, either directly or
indirectly, by parasite infections. To test the effects of invasion
history and parasite exposure on heart size, we studied
common-garden-reared toads whose parents were sourced from diverse
locations, and experimentally exposed them to larvae of a nematode
lungworm (Rhabdias pseudosphaerocephala). Offspring of invasion-front
parents had larger hearts than did conspecifics from long-established
populations. Exposure to infective lungworm larvae decreased heart mass in
toads from all populations, possibly reflecting parasite-driven
manipulation of host activity rather than a pathological effect. Our study
suggests that cardiovascular function, like other traits, has evolved
rapidly during the toad invasion, and that lungworm parasites can modify
the cardiovascular function and hence the aerobic capacity of their host.