Morsoravidae

Common to the Morsoravidae is a distinctive morphology of the tarsometatarsus. The trochlea of the second and fourth metatarsals are distinct, and the fourth metatarsal trochlea is slanted in a way that strongly suggests that morsoravids were at least facultatively zygodactyl. The second metatarsal trochlea is characterised by large size (compared to Psittacopedidae and Zygodactylidae) and a cylindrical shape that allows little rotational movement of the toe. These adaptations are thought to improve these birds' climbing ability.^[2]

One morsoravid, a 47-million year old specimen of Pumiliornis tesselatus, has been found with pollen grains in its gut,^[3] indicating at least some level of nectarivory.^[2] Another morsoravid, Sororavis solitarius, is similar to mousebirds in details of the legs, suggesting that it could have been able to hang off of branches to reach food items.^[2]

Although most of the named species of Morsoravidae are known from European sites, Consoravis was discovered in the Green River Formation in the United States.^[1] Other morsoravids are known from the Fur Formation of Denmark, the Messel Pit in Germany, and the London Clay of England.^[2]