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Predation is an interaction between two species in which one predator eats the other species, which is prey. This interaction has a beneficial effect on the predator population while having a negative impact on the prey population.

Both predators and prey evolve themselves with time because of this interaction.

During parts 2 and 3, researchers collected snakes from sites where cane toads had been present for 5-60 years. They administered cane toad venom into the snakes' stomachs and measured their swimming speed in a small pool to see how it affected their physiological activity.

The red-bellied black snake is one native species that toads have severely impacted.Snakes' adaptive and learning behavior in response to venomous toads is that they willhunt on cane toads in certain regions. Still, they are more likely to prey on local frogs.

Snakes in the region where cane toads lived had learned that cane toads were venomous, so they chose the native frogs when forced to choose between the two.

Since snakes in areas without cane toads had never been exposed to the venom of cane toads, half of them ate cane toads.