in the process. This led to the fitness of larger-shelled prey to be higher and then more selected for through generations, however, the predator’s population selected for those who were more efficient at opening the larger-shelled prey. This example is an excellent example of asymmetrical arms race because while the prey is evolving a physical trait, the predators are adapting in a much different way. Floodplain death adders and separate species of frogs Floodplain death adders eat three types of frogs: one nontoxic, one producing mucus when taken by the predator, and the highly toxic frogs, however, the snakes have also found if they wait to consume their toxic prey the potency decreases. In this specific case, the asymmetry enabled the snakes to overcome the chemical defenses of the toxic frogs after their death. The results of the study showed that the snake became accustomed to the differences in the frogs by their hold and release timing, always holding the nontoxic, while always releasing the highly toxic frogs, with the frogs that discharge mucus somewhere in between. The snakes would also spend generously more time gaped between the release of the highly toxic frogs than the short gaped time between the release of the frogs that discharge mucus. Therefore, the snakes have a much higher advantage of being able to cope with the different frogs defensive mechanisms, while the frogs could eventually increase the potency of their toxic knowing the snakes would adapt to that change as well, such as the snakes having venom themselves for the initial attack. The coevolution is still highly asymmetrical because of the advantage the predators have over their prey. Introduced species When a species has not been subject to an arms race previously, it may be at a severe disadvantage and face extinction well before it could ever hope to adapt to a new predator, competitor, etc. This should not seem surprising, as one species may have been in evolutionary struggles for millions of years while the other might never have faced such pressures. This is a common problem in isolated ecosystems such as Australia or the Hawaiian Islands. In Australia, many invasive species, such as cane toads and rabbits, have spread rapidly due to a lack of competition and a lack of adaptations to cane toad bufotenine on the part of potential predators. Introduced species are a major reason why some indigenous species