The Somewhat Amusing World of Frogs

a very nice picture of a very nasty frog

Some frogs pretend that they're dead when attacked - which helps when the predator only eats live prey or hunts by movement.
Some frogs have flash markings, so that just before they jump they show really bright markings (on their legs etc.) and a predator focusses on the markings but when they land the markings disappear so that the predator can't see the markings and thinks that the animal is gone:
(Mattison)
Some frogs attack by opening their mouths widely, grunting, screaming, lunging and biting.
As noted above, poison arrow frogs of Central and South America are brightly coloured to warn predators to stay away (they are highly poisonous).
Tadpoles may regenerate limbs etc., although frogs normally don't (some regrowth may occur).
Provided that they defend themselves, frogs generally live from four to forty years (depending on type) with the average being four to fifteen years.
Of course, if a frog has a driving licence it will prefer to drive off at the earliest sign of danger. Which brings us to the what happened to a frog's car when his parking meter expired? It got toad!!