A marine sponge native to the Great Barrier Reef off the coast of Australia. Amphimedon queenslandica

Amphimedon queenslandica. This species exemplifies many sessile and sedentary marine invertebrates (e.g., corals, ascidians, bryozoans): They disperse during a planktonic larval phase, settle in the vicinity of conspecifics, ward off potential competitors (including incompatible genotypes), and ensure that brooded eggs are fertilized by conspecific sperm.