Animals displaying bright coloration and patterning to warn away predators are known as “aposematic,” and include things like coral snakes, skunks, and poison dart frogs (Dendrobatidae). This “blue jeans frog” is bright red and blue as a warning to potential predators that it is very nasty-tasting and/or dangerous to their health… but doesn’t lend them any stealth abilities for avoiding curious and camera-laden humans.
Other fun facts about these frogs: they lay eggs in the leaf litter, fertilize them, allow them to hatch, and then carry the tadpoles on their backs high into the canopy, to deposit them in tiny pools of water caught in bromeliads. The mother will return to feed them every day until they are big enough to grow legs and leave the pools, somehow remembering each tadpole’s location, and providing them with the chemicals in their foods that they will need to retain their parents’ defensive poison.
Another type of animal defense involves not advertisement of unpalatability but simple hiding-in-plain-sight. Tent-making bats like the two species below chew along the midribs of big leaves, collapsing them down into little shelters. They hold on to the midribs with their tiny little feets, and nap through the day bathed in the green light coming through their tent walls. They also build decoy tents, with no bats inside, possibly to foil squirrel monkeys and other bat predators’ efforts to find their real hiding places.
These ones look like cotton balls. Way too cute.
Other interesting defense mechanisms we’ve seen in La Selva include: the armadillos, hard to photograph because they like to crawl around in the underbrush in the dark; fer de lance snakes with a very nasty bite to impart on anything foolish enough to tangle with them; and bullet ants, inch-long little boogers that are named for their ability to make you feel, for 24 full hours, as if you have been shot.
Then there are things like this tamandua (ant-eater) that see potential predators like us, squeak, and waddle over to a too-small tree in order to climb it slowly and cast timid and unhappy looks down at the scientists below. Not maybe as impressive a defense strategy… but still pretty adorable.