Hostname: page-component-7c8c6479df-xxrs7 Total loading time: 0 Render date: 2024-03-28T02:11:33.772Z Has data issue: false hasContentIssue false

Locomotory capabilities in the Early Cretaceous ichthyosaur Platypterygius australis based on osteological comparisons with extant marine mammals

Published online by Cambridge University Press:  01 November 2013

MARIA ZAMMIT*
Affiliation:
Current address: South Australian Museum, North Terrace, Adelaide, South Australia, Australia5000
BENJAMIN P. KEAR
Affiliation:
Palaeobiology Programme, Department of Earth Sciences, Uppsala University, Villavägen 16, SE-752 36 Uppsala, Sweden
RACHEL M. NORRIS
Affiliation:
School of Animal and Veterinary Sciences, Roseworthy Campus, University of Adelaide, Adelaide, South Australia, Australia5371
*
Author for correspondence: maria.zammit6783@gmail.com

Abstract

Reconstructing the swimming capabilities of extinct marine tetrapods is critical for unravelling broader questions about their palaeobiology, palaeoecology and palaeobiogeography. Ichthyosaurs have long been the subject of such investigations because, alongside cetaceans, they are one of the few tetrapod lineages to achieve a highly specialized fish-like body plan. The dominant locomotory mode for the majority of derived, post-Triassic ichthyosaurs is hypothesized to have been caudal fin-driven propulsion. Limb-based swimming has however been suggested for some highly autapomorphic forms, such as the Cretaceous genus Platypterygius, which has a remarkably robust humeral morphology and exceptionally broad paddle-like limbs. To evaluate this atypical lifestyle model, we conducted a comprehensive comparative osteological assessment of Platypterygius in relation to extant marine mammals, whose analogous skeletal frameworks provide a structurally compatible selection of alternate propulsive strategies. Based on a proxy exemplar of the most completely known species, P. australis from the Early Cretaceous of Australia, the propodial shape, absence of functional elbow/knee joints, tightly interlocking carpals, hyperphalangy and extreme reduction of the pelvic girdle are most similar to cetaceans as opposed to pinnipeds or dugongs. There is no obvious structural consistency with aquatic mammals that use sustained forelimb-driven swimming. The exceptionally broad fore-paddle (a product of hyperdactyly) and extensive humeral muscle insertions might therefore have had a cetacean-like role in enhancing manoeuvrability and acceleration performance. We conclude that, despite its atypical features, P. australis was most likely similar to other ichthyosaurs in using lateral sweeps of the tailfin to generate primary propulsive thrust.

Type
Original Articles
Copyright
Copyright © Cambridge University Press 2013 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Abel, O. 1909. Cetaceenstudien. I. Mitteilung: Das Skelett von Eurhinodelphis cocheteuxi aus dem Obermiozän von Antwerpen. Sitzungsberichte der Kaiserlickeh Akademie der Wissenschaften, Wien 118, 241–53.Google Scholar
Alexander, R. M. 1975. The Chordates. Cambridge: Cambridge University Press, 480 pp.Google Scholar
Bardet, N. & Fernández, M. 2000. A new ichthyosaur from the Upper Jurassic lithographic limestones of Bavaria. Journal of Paleontology 74, 503–11.Google Scholar
Baur, G. 1887. Über den Ursprung der Extremitäten der Ichthyopterygia. Jahresberichte und Mitteilungen des Oberrheinischen geologischen Vereines 20, 1720.Google Scholar
Berta, A. & Sumich, J. L. 1999. Marine Mammals: Evolutionary Biology. San Diego, California: Academic Press, 494 pp.Google Scholar
Best, R. C. & da Silva, V. M. F. 1993. Inia geoffrensis . Mammalian Species 426, 18.Google Scholar
Blake, R. W. 2004. Fish functional design and swimming performance. Journal of Fish Biology 65, 1193–222.CrossRefGoogle Scholar
Buchholtz, E. A. 2001 a. Swimming styles in Jurassic ichthyosaurs. Journal of Vertebrate Paleontology 21, 6173.CrossRefGoogle Scholar
Buchholtz, E. A. 2001 b. Vertebral osteology and swimming style in living and fossil whales (Order: Cetacea). Journal of Zoology, London 253, 175–90.Google Scholar
Buchholtz, E. A. & Schur, S. A. 2004. Vertebral osteology in Delphinidae (Cetacea). Zoological Journal of the Linnean Society 140, 383401.Google Scholar
Camp, C. L. 1976. Vorläufige Mitteilung über große Ichthyosaurier aus der oberen Trias von Nevada. Sitzungsberichte der Österreichischen Akademie der Wissenschaften, Mathematischnaturwissenschaftliche Klasse, Abteilung I 185, 125–34.Google Scholar
Cooper, L. N. & Dawson, S. D. 2009. The trouble with flippers: a report on the prevalence of digital anomalies in Cetacea. Zoological Journal of the Linnean Society 155, 722–35.Google Scholar
Cooper, L. N., Dawson, S. D., Reidenberg, J. S. & Berta, A. 2007. Neuromuscular anatomy and evolution of the cetacean forelimb. Anatomical Record 290, 1121–37.Google Scholar
Druckenmiller, P. S., Hurum, J. H., Knutsen, E. M. & Nakrem, H. A. 2012. Two new ophthalmosaurids (Reptilia: Ichthyosauria) from the Agardhfjellet Formation (Upper Jurassic: Volgian/Tithonian), Svalbard, Norway. Norwegian Journal of Geology 92, 311–39.Google Scholar
Druckenmiller, P. S. & Maxwell, E. E. 2010. A new Lower Cretaceous (lower Albian) ichthyosaur genus from the Clearwater Formation, Alberta, Canada. Canadian Journal of Earth Sciences, 47, 1037–53.Google Scholar
English, A. W. M. 1976. Limb movements and locomotor function in the California sea lion (Zalophus californianus). Journal of the Zoological Society, London 178, 341–64.CrossRefGoogle Scholar
English, A. W. M. 1977. Structural correlates of forelimb function in fur seals and sea lions. Journal of Morphology 151, 325–52.Google Scholar
Feldkamp, S. D. 1987. Foreflipper propulsion in the California sea lion, Zalophus californianus . Journal of Zoology, London 212, 4357.Google Scholar
Fernández, M. S. 1997. A new ichthyosaur from the Tithonian (Late Jurassic) of the Neuquén Basin, northwestern Patagonia, Argentina. Journal of Paleontology 71, 479–84.CrossRefGoogle Scholar
Fischer, V., Masure, E., Arkhangelsky, M. S. & Godefroit, P. 2011. A new Barremian (Early Cretaceous) ichthyosaur from western Russia. Journal of Vertebrae Paleontology 31, 1010–25.CrossRefGoogle Scholar
Fish, F. E. 2004. Structure and mechanics of nonpiscine control surfaces. IEEE Journal of Oceanic Engineering 29, 605–21.CrossRefGoogle Scholar
Harrison, R. J. & King, J. E. 1965. Marine Mammals. London: Hutchinson and Co. Limited, 192 pp.Google Scholar
Hildebrand, M. 1974. Analysis of Vertebrate Structure. New York: John Wiley & Sons, 710 pp.Google Scholar
Howell, A. B. 1929. Contribution to the comparative anatomy of the eared and earless seals (genera Zalophus and Phoca). Proceedings of the United States National Museum, 73, 1142.Google Scholar
Husar, S. L. 1977. Trichechus inunguis . Mammalian Species 72, 14.Google Scholar
Jaekel, O. 1904. Eine neue Darstellung von Ichthyosaurus . Zeitschrift der Deutschen Geologischen Gesellschaft 56, 2634.Google Scholar
James, P. B. S. R. 1974. An osteological study of the dugong Dugong dugon (Sirenia) from India. Marine Biology 27, 173–84.Google Scholar
Kear, B. P. 2003. Cretaceous marine reptiles of Australia: a review of taxonomy and distribution. Cretaceous Research 24, 277303.Google Scholar
Kear, B. P. 2005. Cranial morphology of Platypterygius longmani Wade, 1990 (Reptilia: Ichthyosauria) from the Lower Cretaceous of Australia. Zoological Journal of the Linnean Society 145, 583622.Google Scholar
Kear, B. P. & Zammit, M. 2013. In utero foetal remains of the Cretaceous ichthyosaurian Platypterygius: ontogenetic implications for character state efficacy. Geological Magazine, 151, 7186.Google Scholar
King, J. E. 1983. Seals of the World. Oxford: Oxford University Press, 154 pp.Google Scholar
Klima, M., Oelschläger, H. A. & Wünsch, D. 1980. Morphology of the pectoral girdle in the Amazon dolphin Inia geoffrensis with special reference to the shoulder joint and movements of the flippers. Zeitschrift fur Säugetierkunde 45, 288309.Google Scholar
Kolb, C. & Sander, P. M. 2009. Redescription of the ichthyosaur Platypterygius hercynicus (Kuhn 1946) from the Lower Cretaceous of Salzgitter (Lower Saxony, Germany). Palaeontographica Abteiling A 288, 151–92.Google Scholar
Maisch, M. W. & Matzke, A. T. 2000. The Ichthyosauria. Stuttgarter Beiträge zur Naturkunde Serie B (Geologie und Paläontologie) 298, 1159.Google Scholar
Massare, J. A. 1988. Swimming capabilities of Mesozoic marine reptiles: implications for method of predation. Paleobiology 14, 187205.CrossRefGoogle Scholar
Massare, J. A. 1994. Swimming capabilities of Mesozoic marine reptiles: a review. In Mechanics and Physiology of Animal Swimming (eds Maddock, L., Bone, Q. & Rayner, J.), pp. 133–49. Cambridge: Cambridge University Press.Google Scholar
Massare, J. A. & Sharkey, S. J. 2003. Centrum shape in sharks: not a good analog for ichthyosaurs. Paludicola 4, 2736.Google Scholar
Maxwell, E. E. & Kear, B. P. 2010. Postcranial anatomy of Platypterygius americanus (Reptilia: Ichthyosauria) from the Cretaceous of Wyoming. Journal of Vertebrate Paleontology 30, 1059–68.Google Scholar
Maxwell, E. E., Zammit, M. & Druckenmiller, P. S. 2012. Morphology and orientation of the ichthyosaurian femur. Journal of Vertebrate Paleontology 32, 1207–11.Google Scholar
McGowan, C. 1972. Evolutionary trends in longipinnate ichthyosaurs with particular reference to the skull and fore fin. Life Sciences Contributions, Royal Ontario Museum 83, 138.Google Scholar
McGowan, C. 1992. The ichthyosaurian tail: sharks do not provide an appropriate analogue. Palaeontology 35, 555–70.Google Scholar
McGowan, C. 1996. The taxonomic status of Leptopterygius Huene, 1922 (Reptilia: Ichthyosauria). Canadian Journal of Earth Sciences 33, 439–43.CrossRefGoogle Scholar
McGowan, C. & Motani, R. 2003. Ichthyopterygia . In Handbook of Paleoherpetology, Volume 8 (ed. Sues, H.-D.). München: Verlag Dr. Friedrich Pfeil, 175 pp.Google Scholar
M'Coy, F. 1867. On the occurrence of Ichthyosaurus and Plesiosaurus in Australia. Annals and Magazine of Natural History 19, 355–6.CrossRefGoogle Scholar
Motani, R. 1999. On the evolution and homologies of ichthyopterygian forefins. Journal of Vertebrate Paleontology 19, 2841.Google Scholar
Motani, R. 2002. Swimming speed estimation of extinct marine reptiles: energetic approach revisited. Paleobiology 28, 251–62.Google Scholar
Ortega-Ortiz, J. G., Villa-Ramírez, B. & Gersenowies, J. R. 2000. Polydactyly and other features of the manus of the vaquita, Phocoena sinus . Marine Mammal Science 16, 277–86.Google Scholar
Osburn, R. C. 1903. Adaptation to aquatic, arboreal, fossorial and cursorial habits in mammals. I. Aquatic adaptations. American Naturalist 37, 651–65.Google Scholar
Riess, J. 1986. Fortbewegunsweise, schwimmbiophysik und phylogenie der ichthyosaurier. Palaeontographica Abteilung A 192, 93155 (in German).Google Scholar
Romer, A. S. 1956. Osteology of the Reptiles. Chicago: University of Chicago Press, 772 pp.Google Scholar
Seeley, H. G. 1874. On the pectoral arch and fore limb of Ophthalmosaurus, anew ichthyosaurian genus from the Oxford Clay. Quarterly Journal of the Geological Society of London 30, 696707.Google Scholar
Thewissen, J. G. M., Cohn, M. J., Stevens, L. S., Bajpai, S., Heyning, J. & Horton, W. E. Jr. 2006. Developmental basis for hind-limb loss in dolphins and origin of the cetacean bodyplan. Proceedings of the National Academy of Sciences of the United States of America 103, 8414–8.CrossRefGoogle ScholarPubMed
Thewissen, J. G. M. & Taylor, M. A. 2007. Aquatic adaptations in the limbs of amniotes. In Fins into Limbs (ed. Hall, B. K.), pp. 310322. Chicago: University of Chicago Press.Google Scholar
von Huene, F. 1922. Die Ichthyosaurier des Lias und ihre Zusammenhänge. Monogaphien zur Geologie und Paläontologie, 1. Verlag von Gebrüder Borntraeger, Berlin, VIII + 114 pp.Google Scholar
von Huene, F. 1923. Lines of phyletic and biological development of the Ichthyopterygia. Bulletin of the Geological Society of America 34, 463–8.Google Scholar
Wade, M. 1984. Platypterygius australis, an Australian Cretaceous ichthyosaur. Lethaia 17, 93113.Google Scholar
Wade, M. 1990. A review of the Australian Cretaceous longipinnate ichthyosaur Platypterygius (Ichthyosauria, Ichthyopterygia). Memoirs of the Queensland Museum 28, 115–37.Google Scholar
Webb, P. W. 1977. Effects of median-fin amputation on fast-start performance of rainbow trout (Salmo gairdneri). Journal of Experimental Biology 68, 123–35.Google Scholar
Webb, P. W. 1984. Form and function in fish swimming. Scientific American 25, 5870.Google Scholar
Webb, P. W. & Keyes, R. S. 1981. Division of labor between median fins in swimming dolphin (Pisces: Coryphenidae). Copeia 1981, 901–4.Google Scholar
Zammit, M. 2010. A review of Australasian ichthyosaurs. Alcheringa 34, 281–92.Google Scholar
Zammit, M., Norris, R. M. & Kear, B. P. 2010. The Australian Cretaceous ichthyosaur Platypterygius australis: a description and review of postcranial remains. Journal of Vertebrate Paleontology 30, 1726–35.Google Scholar
Supplementary material: File

Zammit Supplementary Material

Figure 1

Download Zammit Supplementary Material(File)
File 5.7 MB