Hesperornis regalis Marsh 1872Marine birds with teeth in the Late Cretaceous seas
Copyright © 2000-2014 by Mike EverhartLast updated 01/19/2014
Detail of a painting by Ely Kish, Copyright © Ely Kish; used with permission of Ely Kish (EMAIL) - Click HERE for the entire painting. |
Hesperornis (pronounced HES-per-OR-nis) means "western bird." Professor O. C. Marsh reportedly found the first remains of a bird (Hesperornis regalis) in the Smoky Hill Chalk of "Trego County" on July 25, 1871 [This locality is suspect - almost all specimens that were collected by the Yale Scientific Expedition in late July came from Logan County, some 40 miles to the west]. The specimen (YPM 1200) was did not include a skull and Marsh had no way of knowing the full significance of his discovery. Marsh (1872a) wrote, "One of the treasures secured during our explorations this year [1871] was the greater portion of the skeleton of a large fossil bird, at least five feet in height, which I was fortunate enough to discover in the Upper Cretaceous of Western Kansas. This interesting specimen, although a true bird --- as clearly as shown by the vertebræ and some other parts of the skeleton -- differs widely from any known recent or extinct forms of that class, and affords a fine example of a comprehensive type. The bones are all well preserved. The femur is very short, but the other portions of the legs are quite elongated. The metatarsal bones appear to have been separated. On my return, I shall fully describe this unique fossil under the name Hesperornis regalis."
Actually, Marsh had found a foot bone of Hesperornis about a year earlier but didn't realize it.
Williston (1898) noted that "late in the season of 1870, Professor Marsh, with an escort of United States soldiers, spent a short time on the upper part of the Smoky Hill River collecting vertebrate fossils. The material then collected served for the description of a number of interesting types by Marsh. It included the first known specimen of 'Odontornithes,' a foot bone brought in with other material, but which was not discovered in the material until after other specimens had been obtained later. In June of the following year Marsh again visited the same region, with a larger party and a stronger escort of United States troops, and was rewarded by the discovery of the skeleton which forms the type of Hesperornis regalis Marsh, together with other material."
In a later article, Marsh (1872b)
noted that the "most interesting bird with teeth yet discovered is perhaps Hesperornis
regalis, a gigantic diver, also from the Cretaceous of Kansas, and discovered by the
writer in 1870." Marsh neglected to mention that the original discovery did not
include a skull or teeth, but adds that "a nearly perfect skeleton was obtained in
Western Kansas by Mr. T. H. Russell and the writer in November, 1872." The reader is
left to assume that this specimen of Hesperornis (YPM 1206) was the first one
discovered with teeth. The skull was
illustrated in Marsh's 1880 monograph on Odontornithes (Plate I).
LEFT: A photograph of the 1872 Yale College Scientific Expedition: O.C. Marsh is standing in the center of the back row. T.H. Russell is sit on the left end of the front row. A larger version of the 1872 expedition is HERE. Note that T.H. Russell went on to become a well respected medical doctor and was Marsh's personal physician at the time of Marsh's death in 1899. |
Marsh, O. C. 1880. Odontornithes: A monograph on the extinct
toothed birds of North America. Report of the Geological Exploration of the Fortieth
Parallel (King), volume 7, xv + 201 p., 34 pl. The first Bird fossil discovered in this region was the lower end of the tibia of Hesperornis [YPM 1205], found by the writer in December, 1870, near the Smoky Hill River in Western Kansas. Specimens belonging to another genus of Odontornithes were discovered on the same expedition. The extreme cold, and danger from hostile Indians, rendered a careful exploration at the time impossible. In June of the following year, the writer again visited the same region with a larger party, and a stronger escort of United States troops, and was rewarded by the discovery of the skeleton which forms the type of Hesperornis regalis Marsh. Various other remains of Odontornithes were secured, and have since been described by the writer. Although the fossils obtained during two months of exploration were important, the results of this trip did no equal our expectations, owing in part to the extreme heat (110o to 120o Fahrenheit, in the shade) which, causing sunstroke and fever, weakened and discouraged guides and explorers alike. A considerable part of these Cretaceous deposits still remained unexplored, and in the autumn of 1872, a third expedition through this territory was undertaken by the writer, with a small party. Additional specimens of much interest were secured, including the type of the genus Apatornis, and one nearly complete skeleton of Hesperornis, -- an ample reward for the hardship and danger we incurred. In the Appendix of that same publication (pages 195-196), Marsh provides additional details on the locality of the early specimens:
“The
type specimen of Hesperornis regalis (number
1200) was found by the
writer, in July, 1871. The locality was on
the south bank of
the Smoky Hill
River, about twenty miles east of See Everhart (2011) for additional information regarding the discovery and the revised age of the type specimen of Hesperornis regalis Marsh. |
LEFT: A model of Hesperornis regalis in the Natural
History Museum at the University of Kansas. The restoration was done by by Melvin Douglas under the direction of H. H.
Lane (see Lane, 1947, p. 393). RIGHT: A close-up of the head of the Hesperornis model. Note the absence of teeth on the premaxilla. A recent paper by Hieronymus and Witmer (2010) suggests that the tooth-bearing bones of Hesperornis (and Ichthyornis) would not have been covered with a horny (keratinous) sheath; rather the maxillae and the dentaries would have been covered with skin and scales or feathers. Only the non-tooth bearing portions of the jaws (premaxillae and predentary) would have been covered with a keratinous sheath (see modified photo). |
LEFT: Diving Hesperornis shown as a detail in the
underwater diorama painting at the Sternberg Museum of Natural History RIGHT: Two hesperornithids are shown here in a detail from a mural by Charles Bonner in the Keystone Gallery. |
According to Williston (1898), "Hesperornis regalis, the best known species of the genus, was a bird measuring about 6 feet from the point of the bill to the tip of the feet when outstretched, or standing about 3 feet high. It was an aquatic bird, covered with soft feathers, wholly wingless, the rudimentary wing bones doubtless being enclosed under the skin, and not at all effective in locomotion. The legs were strong and moderately long; the neck was long and flexible. The bill was long, and was provided with small but effective conical teeth set in the jaw firmly. Those of the upper jaw were few in number and set in the back part, while those of the mandibles formed a complete series. The jaws were united in front by cartilage only, permitting considerable mobility, which was doubtless very serviceable in swallowing their prey, which must have consisted of fishes caught by diving. The bones of the body were solid throughout, not hollow, as in almost all living birds. The sternum had no keel, as in the flying birds, and those descended from flying birds, but was as in the ostrich. The vertebræ and skeleton, aside from the teeth, are not unlike those of modern birds, and, were the skull yet unknown, would be unhesitatingly referred to the subclass to which the ostrich, cassowary, and rhea belong." |
LEFT: A model of the skull of Hesperornis regalis in left lateral view in the collections of the University of Nebraska State Museum (DORSAL VIEW - VENTRAL VIEW). This cast was part of an earlier exhibit about Hesperornis and is probably based on a skull at the Yale Peabody Museum. The model of the complete bird in the exhibit was a composite of two fairly complete Hesperornis specimens acquired from G.F. Sternberg (one in 1936; see below). |
LEFT: Drawing of the skull of Hesperornis regalis in left lateral view (adapted from Gingerich 1973, fig. 1). Note that there were no teeth in the premaxilla. |
LEFT: FHSM VP-2069 - Front limb and rib cage RIGHT: FHSM VP-2069 - Reconstruction of the sternum (light areas are actual bone), with coracoids. Larger view of coracoids is HERE. |
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LEFT: FHSM VP-2069 - Rear upper limb bones, left lateral view RIGHT: FHSM VP-2069 - Left rear foot. Hesperornids had broad, individual toes, not webbed feet. |
LEFT: The reconstructed pelvis of Hesperornis regalis
(UNSM 1212) in left lateral view RIGHT: The femurs of UNSM 1212 in posterior view |
LEFT: The reconstructed tibotarsi of UNSM 1212 in posterior view RIGHT: The tarsometatarsi of UNSM 1212 in anterior view. |
LEFT: Hesperornis
feeding on a school of Enchodus. Copyright 2001 © Carl Buell; used with
permission of Carl Buell.
RIGHT: The Geology Museum at the University of Wisconsin - Madison has collected a significant number of specimens from the Smoky Hill Chalk in Kansas, including the partial remains of a Hesperornis. These photos of their Hesperornis reconstruction were provided by Christopher Ott: |
LEFT: A skeletal reconstruction of Hesperornis regalis in the ancient seas exhibit of the Smithsonian Institution (USNM), Washington, D.C. |
LEFT: A mural depicting a colony of Hesperornis on the shore of the Western Interior Sea. (University of Kansas Museum of Natural History, Lawrence, Kansas) |
"The existence of a small swimming bird contemporary with Hesperornis
is indicated by a nearly perfect tarso-metatarsal bone from the same geologic
horizon." Marsh (1877, p. 86) In terms of the number of known specimens, Baptornis advenus is one of the best known birds from the Late Cretaceous after Hesperornis regalis and Ichthyornis dispar. It was first described by O. C. Marsh (1877) as a new genus closely allied with Hesperornis. It is readily distinguishable from Hesperornis by its smaller size and certain characters of the foot (Martin and Tate, 1976). LEFT: Skeletal reconstruction of Baptornis advenus, adapted from Martin and Tate, 1976, Figure 19) |
|
LEFT: A fairly complete skeleton of Baptornis advenus
(UNSM 20030) collected by G.F. Sternberg and acquired by the University of Nebraska State
Museum in 1937. The skeleton includes vertebrae, ribs, uncinate processes, wing bones, half of the pelvis, and most of both legs, as well as preserved intestinal contents (colonites). Recent (2008) photographs of the remains are shown on the Baptornis web page. |
LEFT: A small exhibit of hesperornithid bones in the Fick Fossil and
History Museum, Oakley, Kansas, many of which are probably from the same specimen.
Collected and donated by Vi and Earnest Fick. Bone at the upper left is a
humerus. As
noted by Martin and Tate (1976). this exhibit may also include some bones of Baptornis
advenus. RIGHT: A copy of Figure 20 from Martin and Tate (1976) showing three Baptornis feeding on small fish. The sketch is on display in the exhibit at the Fick Fossil and History Museum in Oakley, Kansas. |
RIGHT: PLATE VIII.--- Photograph of scutes and feather impressions
of the tarsal region of Hesperornis specimen (KUVP 2287) published Williston in
the University Geological Survey of Kansas. Enlarged. S. W. Williston (1898) wrote "A specimen now in the University Museum, collected by Mr. H. T. Martin recently [1894, Graham County], is remarkable in showing the scuta of the tarso-metatarsal region, together with the feathers. A photographic reproduction of this part of the specimen is shown in Plate VIII. I have sketched in the tarso-metatarsal bone, to show it's position. Indications of feathers are also seen on the back portion of the head, and everywhere they appear to be more plumulaceous than the ordinary type of feathers." (Williston, S. W., 1898. Birds. The University Geological Survey of Kansas, Part 2, 4:43-53, pls.5-8.) See also Williston, 1898, On the dermal covering of Hesperornis. NOTE: KUVP 2287 was re-described by Larry Martin (1984) as the type specimen of
a new genus and species of hesperornithid bird, Parahesperornis alexi. |
LEFT: The pelvis of the type of Parahesperornis alexi (KUVP
2287) in left lateral view. RIGHT: The femurs and tibiotarsi of KUVP 2287 |
This new species of Baptornis was described by James
Martin and Amanda Cordes-Person from a specimen discovered some years ago by Dan Varner in the Pierre Shale of western South Dakota. Martin, J. E. and Cordes-Person, A. 2007. A new species of the diving bird Baptornis (Ornithurae: Hesperornithiformes) from the lower Pierre Shale Group (Upper Cretaceous) of southwestern South Dakota. The Geological Society of America, Special Paper 427: 227-237. ABSTRACT: "Fossil birds are relatively rare in Cretaceous deposits of the Northern Great Plains, so the discovery of a large, new diving bird was unexpected. From marine deposits of the Niobrara Formation in Kansas small diversity of birds was known, but until now the large diving bird, Hesperornis was the only bird taxon known from the Pierre Shale Group of South Dakota. The new discovery, a partial skeleton of another diving bird, Baptornis, was secured from the Sharon Springs Formation (lower middle Campanian) of the Pierre Shale Group in Fall River County, South Dakota. The specimen is represented by vertebrae, pelvic fragments, and lower leg elements that are similar to but much more robust than Baptornis advenus from the subjacent Niobrara Formation. The new taxon is nearly twice the size of the Niobrara species, principally in robustness rather than in length of elements. Overall, the specimen represents the first occurrence of Baptornis from the Pierre Shale Group, represents a new species, and indicates greater diversity of birds from the Pierre Shale Group than was previously known." Etymology: Named for Daniel Varner who found the specimen, and for his notable contributions to paleontology in the form of artistic renderings of extinct vertebrates. |
A very early Enaliornis-like bird from North America (The oldest bird remains in the United States)
Enaliornis (Seeley, 1876) is a genus of hesperornithine birds from the Early Cretaceous Cambridge Greensand of England. Two species have been described: Enaliornis barretti and E. sedgwicki. Although remains are fragmentary and incomplete, this is currently the oldest known hesperornithine. In June, 1979, two fragments of a Enaliornis-like tarsometatarsus were surface collected from the basal Lincoln Limestone Member of the Greenhorn Limestone in western Russell County, Kansas. The limb bone would have come from a swimming bird somewhat smaller than Hesperornis or Baptornis. The specimen was mentioned by Martin (1983) and Tokaryk, et al. (1997) but was never fully described or figured. The English Enaliornis material was re-described more recently by Galton and Martin (2002).
See: Everhart, M.J. and Bell, A. 2009. A hesperornithiform limb bone from the basal Greenhorn Formation (Late Cretaceous; Middle Cenomanian) of north central Kansas. Journal of Vertebrate Paleontology 28(3):952-956.
LEFT: Two views of the proximal and distal ends of the right
tarsometatarsus (FHSM VP-6318) of an Enaliornis-like bird from the basal
Greenhorn Limestone (Middle Cenomanian) of Kansas. This specimen represents the oldest
bird bone in Kansas and the United States, and is almost as old as the material
described from the Carrot River area in Saskatchewan, Canada by Tokaryk, et al., 1997, which is currently
the oldest bird fauna in North America. Their specimens also included an Enaliornis-like
bird. (Everhart and Bell, 2009) RIGHT: Four views of the distal end of the specimen. The tarsometatarsus is a bone in the lower leg of birds. It is formed from the fusion of several bones homologous to the ankle (tarsal) and foot (metatarsal) of mammals. (See skeletal drawing of a Hesperornis leg HERE) |
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