How Do Predators Detect Their Prey
How do animals find food when they are hungry? Vison, smell, sound, vibration, temperature, and electromagnetic sensing are all used to detect prey. Some predators use all of these senses, others use only one.
Toads and frogs use just their eyes to detect prey, but not just anything will trigger them to snap their tongues and catch their prey. For example, putting a dead fly in front of a frog will elicit no response, but, if the fly is moving, the frog will orient toward the fly by turning its whole body, snap its tongue and catch the fly, and then wipe its mouth with its right forelimb.
The amazing thing is that frogs can do this as soon as they metamorphose from a tadpole, with no prior experience. How? Frogs have cells called feature detecting cells in the visual part of their brain (Optic tectum) that are sensitive to key features of their prey; size, shape, contrast, and movement