As a very large group of birds, enantiornithines displayed a high diversity of different body plans based on differences in ecology and feeding, reflected in an equal diversity of wing forms, many paralleling adaptions to different lifestyles seen in modern birds. In general, the wings of enantiornithines were advanced compared to more primitive avialans like "Archaeopteryx", and displayed some features related to flight similar to those found in the lineage leading to modern birds, the Ornithuromorpha. While most enantiornithines had claws on at least some of their fingers, many species had shortened hands, a highly mobile shoulder joint, and proportional changes in the wing bones similar to modern birds. Like modern birds, enantiornithines had alulas, or "bastard wings", small forward-pointing arrangements of feathers on the first digit that granted higher maneuverability in the air and aided in precise landings.