SCIENTIFIC CORRESPONDENCE
In a related vein, I am somewhat understood on the basis of individual species probably disappeared around surprised that biology has not found more molecules and their interactions, but 1710-15 (ref. 5). According to what is useful concepts at the intermediate length may be understood in terms of an inter known for the dates of disappearance of scale. Engineering examples include the mediate phenomenon, thixotropy for the Mauritius Dodo and the dates of the arch in architecture, which connects the example. first description of the Rodrigues soli componentry level of bricks with the Robert E. Buxbaum taire, it is likely that most of the travellers overall outcome of cathedrals, and vis Department of Chemical Engineering, who gave an account of the Reunion soli cosity in fluid mechanics, which con Michigan State University, taire did not have the opportunity to see nects the componentry molecular interac East Lansing, these two forms personally. Moreover, tions with the overall fluid responses to Michigan 48824, after the disappearance of the genuine force. Without such intermediate USA Dodo, the names "todaersen" or "dodo" concepts, one is in the position of trying to were used to designate a very different 1. Nature 372. 33 (1994). 5 understand cathedrals by cataloguing the 2. Alberts, B. & Miake·Lye. R. Cell 68, 415-420 bird . bricks. Several phenomena in biology such (1992). The main objection concerning the 3. Schmidt, K. Science 226, 566-567 (1994). as the gel-sol transition accompanying 4. Hlavacek, V., Janssen, R. & Van Rompa, P. Z. Naturf. A attribution of the Reunion solitaire to a animal cell crawling may not be 37,19-45 (1982). member of the ibis family is the question of flight. Among all the writers who men tioned the solitaire, Castleton and Bon Was the solitaire of Reunion an ibis ? tekoe described it as unable to fly, but Dubois indicates some ability to fly when SIR - The Mascarene islands were the downwards than the bill of the different he writes: "This bird has recourse to run home of an extinct family of birds, the species of that genus. Now in one of the ning, as it flies but very little". The other Raphidae, which were large-sized, flight most detailed descriptions of the Reunion writers do not state precisely whether or less Columbiformes. This family includes solitaire, Dubois writes that "the beak is not it could fly4.5. Now, except for one the Mauritius Dodo, Raphus cucullatus like that of a Woodcock but larger" 3.4, characteristic, the skeletal remains of the (Linne), and the Rodrigues solitaire, therefore it must have been relatively long Reunion ibis do not indicate a reduction Pezophaps solitaria (Gmelin). These two and straight. This description of the of flying ability. Because several authors forms are known by contemporaneous bill does not match the description of the described it as very fat, it may have had a Raphidae-bill, but could seasonal fat cycle, with a fat period when correspond to a relatively it was unable to fly, and a thin period short, straight ibis-bill (see when it could figure). In conclusion, we think that the soli The other external charac taire described by the early travellers was teristics noted by the early not related either to the Mauritius Dodo, travellers can also corre or to the Rodrigues solitaire, but was spond to an ibis related to probably the extinct Reunion ibis. In this the sacred ibis, T aethiopi case we propose to designate it as T soli cus, or to the straw-necked tarius (Selys-Longchamps, 1848), new ibis, T spinicollis. Accord comb., of which Borbonibis latipes is a Comparison Qetween the fragment of mandible of the Reunion ing to the different authors junior synonym. ibis, from the Marais de l'Ermitage, and the mandible of a the Reunion solitaire was Cecile Mourer-Chauvire recent T. aethiopicus, the sacred ibis. The description by white, or grey and white, or Centre de Paleontologie Dubois of the beak of the Reunion solitaire, "like that of a "white with the tips of the stratigraphique et Paleoecologie Woodcock, but larger", matches that of an ibis with a relative• wings and tail black" 3,4. In associe au CNRS (URA 11), ly short, straight bill, and is very different from the bill of the the sacred ibis, the wing Universite Claude Raphidae, which is very strong, inflated at the end, with a sort 3 tips are black with metallic Bernard - Lyon 1, of incurved, downturned hook ,? (36% of original size). glints, and cover the tail, 27-43 Bvd du 11 Nov" descriptions and illustrations, by a few which is white. In the straw-necked ibis 69622 Villeurbanne Cedex, anatomical remains for the dodo, and by a the neck, underpart and tail are white, France large number of fossil remains for both while the back and wings are glossy black. Roger Bour species. Moreover, Dubois writes: "The tail feath Museum national d'Histoire nature/le, In Reunion there existed a bird called ers resemble those of an ostrich". Now in Laboratoire des Reptiles the solitaire, exclusively known by histori the sacred ibis, during the reproductive et Amphibiens, cal reports. Excavations recently carried period, the ornamental feathers situated 25 rue Cuvier, 75005 Paris, out in Reunion did not reveal any remains on the back and at the wing tips, filiform, France of Raphidae, but remains of an extinct downturned, and longer than the tail, look Sonia Ribes ibis, Borbonibis latipes,,2, were found in more or less similar to the tail feathers of Museum d'Histoire naturelle, three localities and were particularly an ostrich. The solitaire of Reunion had a 1 rue Poivre, 97400 Saint-Denis, abundant in the Marais de l'Ermitage. long neck and long legs. Together with the La Reunion, This species must have been relatively shape of the bill, these last two character France common; strangely, the early travellers istics correspond to a bird that is very dif 1. Mourer-Chauvin§, C. & Moutou, F. C. Acad. Sci., Paris II, never mentioned it, although they men ferent from the Mauritius Dodo. Finally, 305, 419-423 (1987). tioned almost all the species that have the only indication concerning its food, 2. Cowles, G.S. Geobios 27, 87-93 given by Feuilley: "Their food is but (1994). subsequently been found in the different 3. Strickland, H.E. & Melville, A.G. The Dodo and its fossiliferous localities. worms and filth (saletc) taken on or in the Kindred ( Reeve, Benham & Reeve, London, 1848). The osteological analysis of Borbonibis soil" 4, 5 corresponds much better to an ibis 4. Barre, N. & Barau, A. Oiseaux de fa Reunion (5t. Denis, Reunion, 1982). shows that it is closely related to the recent than to Raphidae; the latter were mainly 5. Cheke, A.S. in Studies of Mascarene Island Birds (ed. genus Threskiomis. However, a fragment frugivorous 6. Diamond, A.W.) 5-89 (Cambridge Univ. Press, 1987). 6. Livezey, B.C. J. Zool. 230, 247-292 (1993). of lower jaw, found in 1994, shows that its The Reunion solitaire was observed by 7. Newton, A. & Newton, E. Phil. Trans. R. Soc. 159, bill was much shorter and less curved explorers between 1613 and 1708, and the 327-362 (1870). 568 NATURE . VOL 373 . 16 FEBRUARY 1995