Alaskan Wood Frogs freeze during winters. 2/3rds of their body water turns into ice, hearts stop beating & blood stops flowing. They build up high concentrations glucose in their organs & tissues which prevents cells from shrinking/dying. When spring arrives, they thaw out and hop away.
Before modern refrigerators, Russian and Finnish people would keep live brown frogs in their milk to keep it fresh. It was found that the secretions made by the frogs basically act as antibiotics, killing bacteria, and keeping the milk fresh and safe to drink.
Poison dart frogs raised in captivity are completely nontoxic. This is because they do not manufacture their own toxins. Instead, they simply concentrate toxins found in the insects they eat. When fed nontoxic insects, they cannot obtain the toxins, rendering them completely harmless.
There is a frog from Africa, Trichobatrachus robustus, that breaks a bone in its toe pad, pushes the sharp broken bone through it’s skin, and tries to shank you with it if it feels threatened.
There is a frog which lets itself completely freeze into a ‘frogsicle’ every Winter. Its heart stills, blood stops flowing, and eyes go white because its lenses freeze. In the Summer it thaws and hops away, good as new.
Poison Dart Frogs are poisonous due to the diet. Frogs raised in captivity are not poisonous.
There is a species of frog that will intentionally break its bones to make ‘claws’ as a form of self-defense.
There is a species of frog in Alaska that freezes during the winter and while frozen, the frog stops breathing, its heart stops beating, its blood stops flowing, and it cannot move. However, when spring arrives, the frog’s body thaws and the frog returns to normal life.
In the 50s physicians performed accurate pregnancy tests by injecting urine from the supposedly pregnant women into a frog. If the frog produced eggs within 24 hrs the test was positive.
The poison-arrow frog contains enough poison to kill 2,200 people.