[JohnMakin]

Taxonomically there is no rule about the differences between toad/frog. Generally “frogs” are considered to be more aquatic than toads, but I’m pretty sure the naming is not entirely consistent amongst species. Funny game, it definitely throws some hard ones at you.

[jna_sh]

That is very much the intent of the game! Frog vs toad is what's known as "folk taxonomy", taxonomy based on people's informal observations and characterisations, and not on the principles of scientific taxonomy. There's a lot of common everyday examples of folk taxonomy that people don't realise aren't "scientific", and are very confident about, and the progression of species in this game was intended to really poke at what people know makes a frog and a toad.