Traditionally, biologists have regarded evolutionary processes as being slow – and far too slow for ongoing evolutionary responses to be relevant to conservation biology. Recent research on invasive species is challenging that idea, and revealing remarkably rapid evolutionary modifications both of invasive species in their new ranges, and of native species that are affected by the invader. In this talk I will focus on the invasion of tropical Australia by cane toads (Bufo marinus). Although toads have been spreading through Australia for less than 80 years, they have already been substantially modified by the new selective forces they have encountered. Over the same period, native predators that are threatened by these toxic invaders have adapted in ways that enable them to survive the toad invasion. An evolutionary perspective not only can help us to understand the impacts of an invasion, but also can suggest novel approaches to reducing those impacts. For example, all invasive species will exhibit some evolutionary “mismatches” to the conditions in their new range, and we can exploit those mismatches to achieve more effective control of the invader.

Although Charles Darwin warned that we should never classify animals as “higher” or “lower”, many biologists continue to implicitly assume that “higher” vertebrates (mammals and birds) are more complex and sophisticated than “lower” vertebrates such as reptiles. In most cases, that assumption is wrong. Recent research on reproductive biology of snakes and lizards has revealed far greater complexity and sophistication than was apparent from earlier studies. For example, the modes of sex determination in reptiles are complex, including multiple environmental influences as well as genetic ones. Patterns of sexual dimorphism in size and shape are influenced by an array of ecological pressures as well as by “traditional” forms of sexual selection. Sex differences in reproductive behaviour are intricately adapted to local mating systems, and include surprisingly well-developed abilities to locate and evaluate potential mates. The previous view of reptiles as rather stupid, behaviourally inflexible robots is being replaced by a greater appreciation of the subtlety and complexity of their adaptations and mating tactics.