The recent, brief foray into Shoebill territory made now a sensible time to use a few other Shoebill-based images I have here in the Tet Zoo archives. That, and I haven’t been able to finish anything more substantive due to other commitments. We begin with a lateral view of a skull I once photographed – sorry about the crazy colours, once again my fantastic photographic skills have done me proud (this image is a scan of a piece of special paper featuring the image… I think it’s called a photograph [thanks to Victor for providing modified versions]).
Note how robust the jugal is (the thick bar ventral to the eye socket). Also interesting is the dorsoposterior position of the bony nostril: obvious evidence that Balaeniceps has a trunk. No, just kidding, ha ha. In life, the nostril is covered by one of the keratinous plates of the bill and hence is not obvious: this is also the case in frigatebirds, pelicans, gannets and anhingas and is one of several morphological characters that have been used to indicate that these birds are close relatives (Mayr 2003) – a hypothesis that contradicts the ‘more traditional’ interpretation of the Shoebill as a weird member of Ciconiiformes, the group that includes storks and allies. Actually, it’s not ‘more traditional’ at all, but it’s definitely the view that’s been most frequently presented in the popular and semi-technical ornithological literature (a very interesting, and not at all uncommon, phenomenon). The sharply hooked tip of the Shoebill premaxillae has also been suggested to be a shared derived character of shoebills, frigatebirds, pelicans, cormorants and gannets* (Cottam 1957, Mayr 2003) [other topologies are available, however: Hackett et al. (2008) found shoebills, hammerkops and pelicans to form a clade that is the sister-group to a heron-ibis clade; a clade containing frigatebirds, gannets, cormorants and anhingas was the sister-taxon to this pelican-hammerkop-shoebill + heron-ibis clade].
* It’s present in newly hatched chicks but lost during growth.
I don’t know what that hole is on the side of the rostrum: it might be a bullet hole, and I think it is, because if you look at the dorsal view of the same specimen below, a possible exit hole is apparent on the left side (there are two holes on the left side, actually, so I’m not sure what’s happened here). Also neat is that the lacrimal and maxilla are fused, so the antorbital fenestra is reduced to a tiny aperture. I didn’t only photograph this specimen, I also took time to draw part of the palate…
The most noteworthy thing about the Shoebill palate is that the palatines are completely fused along the midline. This is unusual, seen elsewhere only in such birds as toucans, hornbills and frogmouths (where the maxillae are fused along the midline as well, forming an extensive bony palate). On this occasion I was more interested in the fact that the palatines of this individual are strangely asymmetrical, with the right-side bone possessing a posteriorly projecting growth. I have no idea what this is and don’t know what difference it made to the bird when it was alive. This reminds me: one day I’ll publish a short article on neornithine palates. Anyone who’s anyone knows that the two great groups of crown-birds – palaeognaths and neognaths – are classically distinguished on the basis of palatal anatomy, but the key differences are hardly ever explained usefully in the literature. I’ll come back to this, be patient.
Finally, a masterpiece. I discovered the picture below by chance recently while clearing out a desk drawer: it was done in 1993, while I was at college, and comes from my brief phase of depicting poorly known fossil birds as interesting garish cartoons. The scene depicts animals preserved in the Jebel Qatrani Formation (deposited during the Late Eocene and Early Oligocene) of Egypt: the extinct shoebill Goliathia andrewsi is putting the smack down on the substantially larger Eremopezus eocaenus. Eremopezus (most recently analysed by Rasmussen et al. (2001)) is of uncertain affinities; a few similarities with palaeognaths have been mentioned on occasion, but (unlike a palaeognath) it seems to have been able to manipulate things with its toes, and superficial similarities with secretarybirds and…. shoebills were suggested by Rasmussen et al. (2001).
And, no, this is not meant to be a rigorously accurate bit of palaeontographic art: Goliathia is known only from an ulna (a partial shoebill tarsometatarsus from the Jebel Qatrani (Rasmussen et al. 1987) may also belong to it) and we have no real idea of what it looked like, while Eremopezus (looking here like a gastornithid) is known only from hindlimb elements and is also of unknown appearance (aaand I screwed up here in showing it lacking a hallux, whereas it definitely had one). As for the pigeon, err…
Having mentioned Goliathia, other fossil shoebill specimens are on record: the first is a partial distal end of a tarsometatarsus from the Upper Miocene of Tunisia, recognised as that of a shoebill by Rich (1972). Harrison & Walker (1982) later described a very similar fossil (also a partial distal end of a tarsometatarsus) from the Upper Miocene of Pakistan and suggested that it and the Tunisian fossil represented the same species, Paludiavis richae. If they’re right, then shoebills once inhabited Asia as well as Africa. And, for the sake of google, let me note here that Balaeniceps has conventionally been given its own ‘family’, Balaenicipitidae, and – sometimes – its own ‘order’ too, Balaenicipitiformes.
Incidentally, for more cartoons depicting obscure fossil birds, check out the Talpanas article here. For more on the Shoebill, see…
And for more on other Cenozoic fossil birds, and on neornithine birds probably closely related to the Shoebill, see…
- Life-size two-dimensional condors and teratorns
- Titan-hawks and other super-raptors
- 2007: a good year for terror birds and mega-ducks
- You’re not a proto-phorusrhacid, but you’re still a cariamaen, and that’s alright with me (ode to the Ameghinornithidae)
- Raven, the claw-handed bird, last of the phorusrhacids
- Gannets, most awesome of seabirds
- Fascinated by boobies
- March of the (small, plastic) pelicans
Refs – –
Cottam, P. A. 1957. The pelecaniform characters of the skeleton of the Shoebill Stork Balaeniceps rex. Bulletin of the British Museum (Natural History), Zoology 5, 51-72.
Hackett, S. J., Kimball, R. T., Reddy, S., Bowie, R. C. K., Braun, E. L., Braun, M. J., Cjojnowski, J. L., Cox, W. A., Han, K.-L., Harshman, J., Huddleston, C. J., Marks, B., Miglia, K. J., Moore, W. S., Sheldon, F. H., Steadman, D. W., Witt, C. C. & Yuri, T. 2008. A phylogenomic study of birds reveals their evolutionary history. Science 320, 1763-1768.
Harrison. C. J. O. & Walker, C. A. 1982. Fossil birds from the Upper Miocene of northern Pakistan. Tertiary Research 4, 53-69.
Mayr, G. (2003). The phylogenetic affinities of the Shoebill (Balaeniceps rex) Journal of Ornithology, 144 (2), 157-175 DOI: 10.1007/BF02465644
Rasmussen, D. T., Olson, S. L. & Simons, E. L. 1987. Fossil birds from the Oligocene Jebel Qatrani Formation, Fayum Province, Egypt. Smithsonian Contributions to Paleobiology 62, 1-20.
– ., Simons, E. L., Hertel, F. & Judd, A. 2001. Hindlimb of a giant terrestrial bird from the upper Eocene, Fayum, Egypt. Palaeontology 44, 325-337.
Rich, P. V., 1972. A fossil avifauna from the Upper Miocene Beglia Formation of Tunisia. Notes du Service géologique 35, 29-66.