[5][6] New fossil finds from two locations, including the Red Hills Fissure, show that the bird has a unique modification of the carpometacarpus, rendering it club-like.

[3] The metacarpal is enlarged and bowed distally with thickened walls, while the ulna and radius have been modified as well.

From its maximum femur diameter of 8.7 mm, it has been estimated that the Jamaican Ibis weighed about 2 kg (70 oz).

[3] Ornithologists speculate that the wings were used as weapons, in the manner of a club or flail,[3] similar to the adaptations found in some mantis shrimps (Stomatopoda: Gonodactyloidea) that possess a club-like distally inflated dactyl used to strike prey and other shrimps.

[3] In birds, adaptations of the wing that are advantageous in the context of fighting represent an example of contingency in which species find different solutions to the same problem as a result of random variations.