This fossorial (burrowing) frog is the only living member of the family Rhinophrynidae. It spends most of its life burrowing, coming to the surface to breed, and its tongue is specialized for eating termites. It uses a spade on the inner edge of its foot for digging.

"Ravoux's slavemaker ant (Myrmoxenus ravouxi) is a species of ant endemic to Europe. The species are helotistic, that is, they oppress another species of ant in order to sustain their colony.[1] The queen will fake death to entice ants from another colony to drag her back to their nest, where she awakens and kills the nest's original queen. She will then cover herself in the dead queen's pheromones, and will begin producing eggs. The slavemaker ants then overrun the colony and then find a new colony to take over."

Small, translucent crustacean that preys on siphonophores, jellyfish, and salps. It divides and recycles the gelatinous parts of its prey with its sharp claws and subsequently fashions a transparent barrel which it pushes with clawed arms. The barrel acts as a home, and as phronima grow, they build larger and larger barrels. They lay eggs and raise their young in these gelatinous barrels as well.

Believed by some to be very similar to the ancestral species of the Darwin's finches, and one of the best examples of ecological release. According to E. O. Wilson, "The birds, all members of a single freely breeding species, occupy niches ordinarily divided among species, genera, and even entire families of birds". Individuals specialize in one type of food for several weeks to an entire lifetime. Feeds variously on insects, spiders, mollusks, small lizards, seeds, fruit, and nectar. "Young birds appear to prosper with personalized instruction".

Believed by some to be similar to the ancestral species of the Lake Victoria cichlids in that two radically different feeding types exist, and interbreed, throughout populations of this species. The papilliform (slender jaws and teeth) and the molariform (thick jaws and pebble shaped teeth).

Discovered in 1983 by Danish Zoologist Reinhardt Kirstensen. Represented an entirely new phylum at the time. Resembles a pineapple and covered in rows of spines and scales. Lives in course sand 10 to 500 meters on ocean bottoms throughout the world.

Caterpillars of this genus have abandoned their plant based diet to become ambush predators.