A male Darwin’s frog with a vocal pouch full of tadpoles. He carries them around until they develop into froglets and hop out of his mouth. (Natural World - BBC)
The sex of the platypus is determined by a set of 10 chromosomes (way different than any other mammal)!
Male platypuses also have spurs on their hind limbs that can inject another animal with venom! They are one of the few venomous mammals out there.
Here’s something I’ll bet you didn’t know: clownfish are sequential hermaphrodites. They start out as males, and as they mature, they can turn into females. There are only two breeding fish in a group, the largest of which is the female. If she is removed, the next highest ranked fish (the breeding male) will transition into a female, and the remaining males will move up in rank based on size.
This is the sarcastic fringehead, a marine fish that lives off the Pacific coast. This species is very territorial; when another fringehead comes over, they will engage in mouth wresting, where they both open up their mouths and basically press their distended mouths together. This helps them determine who is largest and will take over the area.
This is the gastric-brooding frog. The female of this species swallows their fertilized eggs and allows them to hatch and develop in the stomach. Once the babies are developed enough, the mom basically throws them up!
Unfortunately, this species is recently extinct :(
The blobfish is basically a gelatinous mass of a fish that lives in the deep ocean primarily off of Australia. Very little is known about this species because of their extreme environment, but it is believed that the species is threatened due to deep-sea fishing.
Kiwis, the chicken-sized flightless birds of New Zealand, have particularly interesting reproduction habits. Their eggs are the largest in relation to their body size of all bird species. These eggs can weigh up to 1/4 of the weight of the female (it’s about 6 times the size of a chicken’s egg).
This is the Giganotosaurus (this specific fossil cast can be found at Fernbank Museum of Natural HIstory in Atlanta). It looks a lot like T-rex though, doesn’t it? This dinosaur is actually bigger than T-rex by about 6 feet in length!
The easiest way to tell the two dinosaurs apart is by the number of toes on their hands. T-rex has 2 fingers, while Giganotosaurus has 3.