Jamaican ibis
The Jamaican ibis, Jamaican flightless ibis[1] or clubbed-wing ibis[2] (Xenicibis xympithecus) is an extinct bird species of the ibis subfamily uniquely characterized by its club-like wings.[3] It is the only species in the genus Xenicibis,[1] and one of only two flightless ibis genera,[2][3] the other being the genus Apteribis endemic to Hawaii.[2][4]
Jamaican ibis | |
---|---|
Scientific classification | |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Pelecaniformes |
Family: | Threskiornithidae |
Genus: | †Xenicibis Olson & Steadman, 1977 |
Species: | †X. xympithecus |
Binomial name | |
†Xenicibis xympithecus | |
Former range (in red) |
Description
The species was first described in 1977 based on postcranial bone elements excavated in a cave deposit at Long Mile Cave, Jamaica, by H. E. Anthony in 1919–20.[1][5] At the time, it was presumed to be flightless based on the incomplete coracoid;[1] its flightlessness was confirmed after a humerus of the same species was found in the Swansea Cave, Jamaica.[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. This was a large ibis, weighing about 2 kg (70 oz).[3]
Clubbed wing function
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.[7] However, among birds, this adaption appears to be unique.[3] Adaptations of the wing to fight in birds is an example of contingency in which various bird species find different solutions to the same problem based in chance.[3][8]
Distribution
The Jamaican ibis was endemic to Jamaica. Bones have been excavated from several caves, including the Long Mile Cave,[1] the Swansea Cave,[6] the Jackson's Bay Cave[9] and the Red Hills Fissure.[3] Bones from Cuba claimed to be of this genus[10] were later identified as those of a limpkin. Jamaica and Cuba have always been separated by the sea, so it is improbable that a flightless species could reach the other islands.[5]
References
- Olson, Storrs L; Steadman, David W (1977). "A new genus of flightless ibis (Threskiornithidae) and other fossil birds from cave deposits in Jamaica". Proceedings of the Biological Society of Washington. 90 (2): 447–457.
- Tyrberg, Tommy (2009). "Holocene avian extinctions". In Turvey, Sam (ed.). Holocene Extinctions. Oxford University Press. pp. 63–106. ISBN 978-0-19-953509-5.
- Longrich, N. R.; Olson, S. L. (2011). "The bizarre wing of the Jamaican flightless ibis Xenicibis xympithecus: a unique vertebrate adaptation". Proceedings of the Royal Society B: Biological Sciences. 278: 2333–2337. doi:10.1098/rspb.2010.2117. PMC 3119002. PMID 21208965.
- Olson, Storrs L.; Wetmore, Alexander (1976). "Preliminary diagnoses of two extraordinary new genera of birds from Pleistocene deposits in Hawaiian Islands" (PDF). Proceedings of the Biological Society of Washington. 89: 247–258. Retrieved January 7, 2011.
- Suárez, William (2001) "Deletion of the flightless ibis Xenicibis from the fossil record of Cuba" Archived 2011-10-01 at the Wayback Machine. Caribbean Journal of Science 37 (1–2): 109–110
- Olson, Storrs L; Steadman, David W (1979). "The humerus of Xenicibis, the extinct flightless ibis of Jamaica". Proceedings of the Biological Society of Washington. 92: 23–27.
- Patek, S. N.; Korff, W. L.; Caldwell, R. L. (2004). "Biomechanics: Deadly strike mechanism of a mantis shrimp". Nature. 428 (6985): 819–20. Bibcode:2004Natur.428..819P. doi:10.1038/428819a. PMID 15103366.
- Gould, Stephen J (1989). Wonderful Life: The Burgess Shale and the Nature of History. New York: W. W. Norton. pp. 347. ISBN 0-393-02705-8.
- McFarlane, D A; Lundberg, J; Fincham, A G (August 2002). "A late Quaternary paleoecological record from caves of southern Jamaica, West Indies" (PDF). Journal of Cave and Karst Studies. 64 (2): 117–125.
- Arredondo, Oscar (1984). "Sinopsis de las aves halladas en depósitos fosilíferos pleisto-holocénicos de Cuba". Reporte de Investigación del Instituto de Zoología (in Spanish). 17: 1–3.