Amazon Milk Frog
The Amazon Milk Frog (Trachycephalus resinifictrix) is an interesting nocturnal frog native to the humid rainforest regions of northern South America. They can grow up to 10 cm long and have bumpy, granular skin, and as juveniles they’re coloured with bands of black and white, but when they grow older, the colours change to different shades of grey. However, their name doesn’t come from their colouration—it actually comes from the white, milky, poisonous substance the frog produces when it’s threatened. The males have large vocal sacs, so they’re capable of producing loud calls—and they use it to their advantage in their mating strategy. The male chooses a spot inside of a large tree, then calls for a female to come and lay a clutch of about 2,000 eggs. He fertilizes them and watches over them, and then calls another female and tricks her into laying her eggs too, but this time he doesn’t fertilize them—instead, he just leaves them as food for his first batch of tadpoles. Pretty rude, huh?