Active matter refers to systems composed of elements self-propelled by the dissipation of energy, in which dynamical patterns emerge as is in flocks of birds and schools of fish. Some of researchers on the active matter physics seek to identify unified descriptions of such collective motions through interdisciplinary approaches by biologists and physicists. Owing to such collaborations, experimental studies pertaining to the active matter physics are developing recently, which allows us to verify the proposed mathematical models. Here, we review experimental systems of active matter physics, focusing on animal collectives.