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 found the first remains of a bird (Hesperornis regalis) in the Smoky Hill Chalk of "Trego County" [This locality is suspect - almost all specimens collected in late July came from Logan County.] on July 25, 1871. The specimen (YPM 1200) was without a skull and Marsh had no way of knowing the full significance of his discovery. Marsh (1872) 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."
Class: Aves Subclass: Hesperonithes Order: Hesperornithiformes Family: Hesperornithidae Genus: Hesperornis Marsh, 1872 |
Hesperornithids were large flightless birds that swam in the oceans of the late Cretaceous and preyed on small fish. The lower jaw (dentary) and the back portion of the upper jaw (maxilla) of Hesperornis had many sharp teeth. Hesperornis fossils are rare, and are found only in the upper portions (Campanian age) of the Smoky Hill Chalk. The remains of these birds are more common in Cretaceous deposits to the north of Kansas where the weather was probably cooler. It is likely that they swam and fed much like modern penguins. They were also apparently limited to the Northern Hemisphere, much as modern penguins are limited to the Southern Hemisphere. |  |
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LEFT: A model of Hesperornis regalis in the Natural
History Museum at the University of Kansas. RIGHT:A close-up of the head of the Hesperornis model. Note the absence of teeth on the premaxilla. |
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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. |
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LEFT: The restored skeleton of Hesperornis regalis Marsh
(about 1/6 life size). Adapted from Plate VI, The University Survey of Kansas,
Volume IV, Paleontology, Part I, Upper Cretaceous, Samuel W. Williston, Paleontologist,
Kansas State Printer, 1898. Williston used Marsh's reconstruction of Hesperornis
for this figure. RIGHT: Bones of the scapular arch of Hesperornis as figured and described by O.C. Marsh in 1877: “The scapula is long and slender, and has no acromial process. The clavicles are separate, but meet on the median line, as in some very young existing birds. The coracoids are short, and much expanded where they join the sternum. The latter has no distinct manubrium, and is entirely without a keel. The wings were represented by the humerus only, which is long and slender, and without any trace of articulation at its distal end. Its position was close to the ribs, and it was probably nearly or quite concealed beneath the integuments, as in Apteryx. This rendered the rudimentary wings of no possible service in flight or swimming.” |
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| 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." |
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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 model was part of an exhibit of a 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). |
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LEFT: One of the more complete skeletons of Hesperornis
regalis (FHSM VP-2069; minus a skull) is in an exhibit at the Sternberg Museum of
Natural History in Hays, Kansas. It is mounted in a 3-D, left lateral view, and exhibits
many of the unusual characters of this group of toothed, swimming birds
(Hesperornithiformes). The pictures below show details of the mounted, partial specimen. |
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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. |
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LEFT: FHSM VP-2293 - Right scapula (above) and right humerus (below). |
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LEFT: FHSM VP-2293 - Right humerus - Note that the wing in Hesperornis was very reduced in size and probably non-functional. |
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LEFT: FHSM VP-2293 - A series of dorsal vertebrae and the proximal ends of two double-headed ribs. |
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LEFT: Right and left lateral views of the posterior dorsal vertebrae and pelvis of Hesperornis regalis (FHSM VP-189) found by Dr. L.D. Wooster of Fort Hays State University near Monument Rocks in Gove County in 1948 while on a fossil hunting trip with George F. Sternberg |
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Click on the thumbnail to see dorsal, lateral, ventral and occipital views of the skull of Hesperornis (adapted from Heilman, G. 1926. The Origin of Birds. London) |
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Upper and side views of the lower jaw of Hesperornis regalis Marsh, cervical vertebrae, and tooth (From Williston, 1898, originally figured in Marsh, 1880). |
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A view of the reconstruction of the highly modified legs and feet of Hesperornis (from a model at the University of Kansas Museum of Natural History). |
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LEFT: The headless skeleton of Hesperornis regalis (AMNH FR 5100) discovered
by the elder Sternberg's son, Charles M. Sternberg, in 1907 in the Smoky Hill Chalk
near Twin Butte Creek, Logan County, Kansas; now in the collection of the American Museum
of Natural History. "Unfortunately, the skull is missing, otherwise the nearly complete specimen is present, and strange to say in normal position. ... Strange indeed was this long-necked diver with its tarsus at right angles with the body and its powerful web-footed feet. The body was narrow, a little over four inches wide, with a backbone like the keel of a boat. The head was ten inches long and armed with sharp teeth." (Sternberg, 1917, p. 265-266) (Note that the sternum and ribs are also missing. |
| G.F. Sternberg's description of the specimen shown below: "The following bones are present in this specimen: fifteen vertebrae (cervical and dorsal); one femur, one patella, one post-pubis, one tarso-metatarsal, three toes, three ribs with unicate process, and other fragments which are not on exhibition. Remarks: This great flightless bird which had teeth, reached a length of nearly six feet. Its wings were rudimentary and of no use in either air or water, but the great feet were webbed. They were used to paddle in the sea with an outward lateral instead of a downward stroke. Few skeletons, which are anything like complete, have been found of this bird. All are from western Kansas." |
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LEFT: The partial remains of a Hesperornis regalis (UNSM
1212) collected by George Sternberg and sold to the University of Nebraska State Museum in
1936. (Adapted from a photo by G.F. Sternberg - SP 107-31). Sternberg's note
said: 4-19-5-36 Hesperornis regalis (toothed bird) Horizon: Niobrara Cretaceous, blue shale Locality: About five miles southeast of Russell Springs, Kansas. Logan Co. Discovered by Mrs. M.V. Walker. |
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LEFT: The reconstructed pelvis of Hesperornis regalis
(UNSM 1212) in left lateral view RIGHT: The femurs of UNSM 1212 in posterior view |
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LEFT: The reconstructed tibotarsi of UNSM 1212 in posterior view RIGHT: The tarsometatarsi of UNSM 1212 in anterior view. |
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Hesperornis feeding on a school of Enchodus. Copyright 2001 © Carl Buell; used with permission of Carl Buell |
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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: |
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LEFT: A skeletal reconstruction of Hesperornis regalis in the ancient seas exhibit of the Smithsonian Institution (USNM), Washington, D.C. |
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LEFT: In 1877, O.C. Marsh described Baptornis advenus, a
new genus and species of hesperornithid (repeated in his 1880 monograph at left), on the
basis of a "nearly perfect tarso-metatarsal bone," noting that it was distinct
enough from Hesperornis to justify a new species. Since then, however, Schufeldt
(1915b) noted that the specimen more likely represents the opposing ends of similar bones
from two different individuals, and Martin and Tate (1976) indicated that the Yale Peabody
Museum had given a seperate number to each portion (YPM 1465 (distal) and YPM 5768
(proximal)). RIGHT: Marsh's figure of the tarsometatarsus of Baptornis advenus was published in 1880. Baptornis was smaller and possibly more primitive than Hesperornis. It also occurs earlier (Santonian) in the Smoky Hill Chalk than does Hesperornis (Campanian). |
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"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) |
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LEFT: A fairly complete skeleton of Baptornis advenus
(USNM 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. |
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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. |
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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. ) 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. Martin, L. D. 1984. A new hesperornithid and the relationships of the Mesozoic birds. Kansas Academy of Science, Transactions 87: 141-150. |
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LEFT: A possible right tibiometatarsus of Parahesperornis
alexi (FHSM VP-______) collected by Pete Bussen in the upper Smoky Hill Chalk (MU 22)
of western Logan County. This lower limb bone is about 9.7 cm in length and came from
swimming bird about the size of a modern cormorant. RIGHT: Proximal and distal end views of the same specimen. The proximal end appears to have some sort of pathology that has destroyed the bone surface in the center of the joint. |
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| 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
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 was 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).
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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 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. RIGHT: Four views of the distal end of the specimen. The tarsometatarsus is a single bone that is found 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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American Ornithologists’ Union. 1910. Checklist of North American birds; 3rd edition. American Ornithologists’ Union, New York, 430 pp.
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Chinsamy, A., L. D. Martin and P. Dodson. 1998. Bone microstructure of the diving Hesperornis and the volant Ichthyornis from the Niobrara Chalk of western Kansas. Cretaceous Research 19:225-235.
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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.
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Martin, L. D. 1984. A new hesperornithid and the relationships of the Mesozoic birds. Kansas Academy of Science, Transactions 87 p. 141-150.
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Williston, S. W. 1898. Bird tracks from the Dakota Cretaceous. The University Geological Survey of Kansas, Part II, 4:50-53, Fig. 2. (Re-publication of photograph originally published by Snow, 1887)
Click Here for Hesperornis and other paleo-life art by Ely Kish
Another drawing of Hesperornis is located Here
