No. Some frogs are brightly colored to mimic a poisonous frog so that predators do think it is poisonous.
Yes.
yes, it gives you cholera
yes there is a poison caterpillar
yes
Yes they all are colorful because they have to attract insects for pollination.
They are a venomous species - yes.
All rattlesnakes are venomous, not poisonous. However, there is no such thing as a Texas bluebonnet rattlesnake.
Yes, poinsettias are poisionous
Yes, except the poisionous ones.
well as a matter of fact, yes they are poisionous.
Yes some frogs are poisonous and you can tell because of their color
The Corroboree frog, especially the Southern Corroboree frog, is endangered due to human encroachment on their habitat, by feral animals, and by extended droughts (this delays mating and thereby causes death for many tadpoles). There is also a fungus introduced to the region that was mostly fatal to the frogs.