When a predator approaches, options are limited – especially if you’re a tadpole. The woodfrog tadpole (Rana sylvatica) is known to stop swimming and sink to the pond bottom, an action called “freezing behavior.”
In one study, researchers exposed woodfrog embryos to some water from a predator’s tank with or without an injured tadpole (1). When the embryos hatched, the ones that had smelled both the predator and injured relative showed very reduced activity (freezing behavior) if re-exposed to just predator-water.
In mice, freezing behavior is affected by the size and speed of an object. Video showing lab mice exposed to various dots indicates that small, slow objects trigger mice to freeze. When exposed to terrifying large dots, mice take off.
- Mathis, A., M.C.O. Ferrari, N. Windel, F. Messier, and D.P. Chivers. 2008. Learning by embryos and the ghost of predation future. Proc Biol Sci. 275(1651): 2603-2607.
Play. It’s well-documented in many mammals and birds. Fish have also been observed leaping over sticks and batting around balls. Frogs play-wrestle and tadpoles ride bubbles. Turtles play tug-of-war (1). Some invertebrates even play. Octopuses, and possibly spiders and wasps, have shown play behaviors too (2).
Welcome to our new playful kittens, adopted from SAFE Haven.
- Burghardt, G.M. 2015. Play in fishes, frogs, and reptiles. Current Biology. 25(1) R9-10
- Zylinski, S. 2015. Fun and play in invertebrates. Current Biology. 25(1) R10-11
Double, double, toil and trouble;
Fire, burn; and cauldron, bubble.
Shakespeare’s witches open Macbeth by tossing a toad into their cauldron, along with parts of snakes, newts, bats and other dejected, unfortunate creatures. Why such a bad rap? After all, people LOVE frogs – they turn into princes, they have good tasting legs, and some cultures consider them lucky. But toads? Feared, reviled. What’s the big difference?
Toads tend to live in drier environments than frogs. In the frog’s aquatic environment, escape is just a hop away. For toads, though, warts are the key to survival. The two large “warts” on a toad, just behind the head, are glands that secrete a substance toxic to the toad’s predators.
Ay, there’s the rub – Toads are associated with poison. They actually produce three kinds of toxins: two affect the heart and one can produce hallucinations. Some cultures have used these chemicals for medical purposes. Perhaps those Shakespearean hags were just brewing up a treatment for edema.
Protect toads! While the American Toad is not threatened or endangered, many other populations of amphibians are experiencing sharp declines.
Learn more about the American Toad (Bufo americanus) and hear it call at http://www.herpsofnc.org/herps_of_NC/anurans/Bufame/Buf_ame.html