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. 2006 Jun 22;273(1593):1545-50.
doi: 10.1098/rspb.2006.3479.

An invasive species induces rapid adaptive change in a native predator: cane toads and black snakes in Australia

Ben L Phillips  1 , Richard Shine
Affiliations

An invasive species induces rapid adaptive change in a native predator: cane toads and black snakes in Australia

Ben L Phillips et al. Proc Biol Sci. .

Abstract

Rapid environmental change due to human activities has increased rates of extinction, but some species may be able to adapt rapidly enough to deal with such changes. Our studies of feeding behaviour and physiological resistance to toxins reveal surprisingly rapid adaptive responses in Australian black snakes (Pseudechis porphyriacus) following the invasion of a lethally toxic prey item, the cane toad (Bufo marinus). Snakes from toad-exposed localities showed increased resistance to toad toxin and a decreased preference for toads as prey. Separate laboratory experiments suggest that these changes are not attributable to learning (we were unable to teach naive snakes to avoid toxic prey) or to acquired resistance (repeated sub-lethal doses did not enhance resistance). These results strongly suggest that black snake behaviour and physiology have evolved in response to the presence of toads, and have done so rapidly. Toads were brought to Australia in 1935, so these evolved responses have occurred in fewer than 23 snake generations.

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Figures

Figure 1
Figure 1
The percentage of black snakes from toad-exposed and toad-naive populations willing to eat a toad or a frog. No snake from a toad-exposed locality would consume a toad. Error bars represent a standard error.
Figure 2
Figure 2
Resistance to toad toxin in toad-exposed and toad-naive populations. A large percentage reduction in speed indicates low resistance to toxin. Hence, snakes from toad-exposed populations exhibited higher resistance to toad toxin.
Figure 3
Figure 3
Resistance to toad toxin as a function of the time a snake population has been exposed to toads. A large percentage represents a low resistance. Hence, the snakes' resistance to toad toxin increases with increasing exposure time.
Figure 4
Figure 4
Can snakes learn to avoid toxic prey? Histograms show the number of prey taken by black snakes before and after exposure to a toxic prey item. Two prey types were used, only one of which was laced with toxin for each snake (see §2).
Figure 5
Figure 5
The effect of repeated doses of toxin on toxin resistance. A large percentage represents a low resistance. Hence, repeated doses of toxin tend to decrease a snake's resistance (albeit, non-significantly). Error bars represent a single standard error.
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References

    1. Arnold S.J. Behavioural variation in natural populations I: phenotypic, genetic and environmental correlations between chemoreceptive responses to prey in the garter snake, Thamnophis elegans. Evolution. 1981;35:489–509. - PubMed
    1. Arnold S.J. Behavioral variation in natural populations—6. Prey responses by two species of garter snakes in three regions of sympatry. Anim. Behav. 1992;44:705–719.
    1. Ashley M.V, Willson M.F, Pergams O.R.W, O'Dowd D.J, Gende S.M, Brown J.S. Evolutionarily enlightened management. Biol. Conserv. 2003;111:115–123. doi:10.1016/S0006-3207(02)00279-3 - DOI
    1. Blows M.W, Hoffmann A.A. A reassessment of genetic limits to evolutionary change. Ecology. 2005;86:1371–1384.
    1. Brockhurst M.A, Morgan A.D, Rainey P.B, Buckling A. Population mixing accelerates coevolution. Ecol. Lett. 2003;6:975–979. doi:10.1046/j.1461-0248.2003.00531.x - DOI

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