title: Constructing an Invasion Machine: The Rapid Evolution of a Dispersal-Enhancing Phenotype During the Cane Toad Invasion of Australia.
abstract: Biological invasions can induce rapid evolutionary change. As cane toads (Rhinella marina) have spread across tropical Australia over an 80-year period, their rate of invasion has increased from around 15 to 60 km per annum. Toads at the invasion front disperse much faster and further than conspecifics from range-core areas, and their offspring inherit that rapid dispersal rate. We investigated morphological changes that have accompanied this dramatic acceleration, by conducting three-dimensional morphometric analyses of toads from both range-core and invasion-front populations. Morphology of heads, limbs, pectoral girdles and pelvic girdles differed significantly between toads from the two areas, ranging from 0.5% to 16.5% difference in mean bone dimensions between populations, with invasion-front toads exhibiting wider forelimbs, narrower hindlimbs and more compact skulls. Those changes plausibly reflect an increased reliance on bounding (multiple short hops in quick succession) rather than separate large leaps. Within an 80-year period, invasive cane toads have converted the basic anuran body plan - which evolved for occasional large leaps to evade predators - into a morphotype better-suited to sustained long-distance travel.
authors.affiliation: School of Life and Environmental Sciences A08, University of Sydney, Sydney, New South Wales 2006, Australia.
authors.forename: C M
authors.initials: CM
authors.lastname: Hudson
authors.affiliation: Anatomy and Developmental Biology, Monash University, Clayton, Victoria 3800, Australia.|Geoscience, Museum Victoria, Carlton, Victoria 3001, Australia.|Paleobiology, National Museum of Natural History, Smithsonian Institution, Washington, District of Columbia 20560, United States of America.
authors.forename: M R
authors.initials: MR
authors.lastname: McCurry
authors.affiliation: Anatomy and Developmental Biology, Monash University, Clayton, Victoria 3800, Australia.
authors.forename: P
authors.initials: P
authors.lastname: Lundgren
authors.affiliation: Anatomy and Developmental Biology, Monash University, Clayton, Victoria 3800, Australia.
authors.forename: C R
authors.initials: CR
authors.lastname: McHenry
authors.affiliation: School of Life and Environmental Sciences A08, University of Sydney, Sydney, New South Wales 2006, Australia.
authors.forename: R
authors.initials: R
authors.lastname: Shine