Infection success data from experimental pairings of cane toad hosts and lungworm parasites

<p>By imposing novel selection pressures on both participants, biological invasions can disrupt evolutionary "arms races" between hosts and parasites. A spatially replicated cross-infection experiment reveals strong divergence in the ability of lungworms (<em>Rhabdias pseudosphaerocephala</em>) to infect invasive cane toads (<em>Rhinella marina</em>) in Australia. In areas colonised for &gt; 20 years, toads are more resistant to infection by local strains of parasites than by allopatric strains. The situation reverses at the invasion front, where super-infective parasites have evolved. Invasion-induced shifts in genetic diversity and selective pressures may explain why hosts win the arms race in long-colonised areas whereas parasites win the arms race at the invasion front.</p>