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A newly discovered track in the Chinle Group north of Moab, Utah, is attributable to the ichnogenus Atreipus, an ichnotaxon that is relatively common in eastern North America (Newark Supergroup) bu...

Type specimens of the sauropod ichnotaxon Chuxiongpus changlingensis, which was later reassigned to Brontopodus changlingensis, as well as the theropod ichnotaxon Yunnanpus huangcaoensis, both from the Cretaceous Jiangdihe Formation of Yunnan Province, are redescribed in order to document their morphological features. Both, but particularly Y. huangcaoensis, which is considered now a nomen dubium, were originally based on poorly preserved material. Nevertheless, the specimens document a saurischian dominated biota that existed during the deposition of the Jiangdihe Formation from which no skeletal remains are known. B. changlingensis trackways were left by small sauropods that show consistent partial or complete overprint of the manus by the pes. This pattern makes it difficult to calculate manus length, and heteropody can be only estimated.

Two tridactyl footprints from the Chuanjie Formation (Middle Jurassic) of Yunnan Province, China are morphological characteristics of thyreophoran tracks. They show some similarities to Shenmuichnu...

In 1991, I referred to the Dinosaur Footprint Renaissance (Lockley, 1991), rather shamelessly appropriating the term from one Bob Bakker (1975) who spoke of the “Dinosaur Renaissance.” The first bo...

One of the goals of vertebrate ichnology is to use trace fossils as an additional source of data to determine the palaeoecological makeup of vertebrate paleoecosystems. The features in both the synapomorphy-based and phenetic-based methods of attributing a trace to an osteologic trackmaker are those that are affected by preservational conditions, convergent due to size and/or habitat of the trackmaker, and are morphologically variable within taxa. Despite the drawbacks, the phenetic-based, or “gestalt” method, is still the most comprehensive, if not always synapomorphy-supported, means of using the largest amount of data (morphologic and behavioral) preserved for identifying tracks as avian. To date there are too few synapomorphies that are both pedes specific and are consistently preserved in footprints to be a practical method for attributing tracks to an avian trackmaker. There is still much more comparative ichnological and statistical work to be done to discern novel traits that can be used to deline...

Literature concerning dinosaur footprints or trackways exhibiting abnormal gait or morphology reflecting pathology (ichnopathology) is rare. We report on a number of Jurassic and Cretaceous occurrences of theropod footprints from western North America with unusual morphologies interpreted herein as examples of inferred pathologies, or ichnopathologies. The majority of ichnopathologies are primarily manifested in the digit impressions and include examples of swelling, extreme curvature, dislocation or fracture, and amputation. A number of occurrences are single tracks on ex situ blocks with substantial deformation (inferred dislocation or fracture), or absence of a single digit impression. Two occurrences are from in situ natural mould trackways, one of which is a lengthy trackway of a presumed allosauroid with no noticeable deformation of the digits or feet but with strong inward rotation of the left footprint toward the midline and a pronounced, waddling limp. The other is a tyrannosaurid trackway consis...

New tracksites reported from the Zizhou area elucidate the nature of the Early-Middle Jurassic dinosaurian ichnofaunas in Shaanxi Province. The assemblage is composed of footprints and trackways of medium- to large-sized theropods that show similarities with both the ichnogenera Kayentapus and Eubrontes and of small bipedal ornithischians that are referred to AS Anomoepus isp. Additionally tracks of a quadruped are present and assigned to Deltapodus isp. that may be related to a stegosaurian. Anomoepus isp. is similar to the holotype of Shensipus tungchuanensis which is, although apparently lost, re-assigned here and considered to be a subjective junior synonym of Anomoepus. It is therefore placed in new combination as Anomoepus tungchuanensis comb. nov. Identical tracks have been reported from well-preserved trackways both in the Zizhou and Shenmu areas, where they also co-occur with theropod tracks (Kayentapus and Grallator) and tracks of quadrupedal ornithischians (Shenmuichnus and Deltapodus). Thus, i...

Cretaceous tetrapod (dinosaur and pterosaur) tracks from Zhaojue County in Sichuan Province are locally very abundant. Large scale quarrying operations at the Sanbiluoga Copper Mine site have produced extensive exposures, and track material for detailed study. However, natural track-bearing outcrops also occur at a site in Jiefang Township. The traditions of the local Yi people, indigenous to the area, attribute such tracks to Zhigealu, a central creator hero-ancestor, who made the footprints while riding his heavenly steed through the area. Through seeing tracks exposed by quarrying the local people offered these legend-based interpretations, and reported the Jiefang site which was previously unknown to scientists from outside the area. Thus, it is important to pay attention to local legends about track makers since they may lead directly to significant fossil footprint discoveries. Thereby paleontology and ichnological research can benefit largely from archeological sciences as well as from oral narrati...

Trackways of ornithopods are well-known from the Lower Cretaceous of East Asia, particularly in Korea and China. However, most morphotypes have been identified as Caririchnium which is characterized by moderate mesaxony, the ratio length = width, or length > width and, in some cases, by a quadrupedal gait. In 2009 the ichnogenus Ornithopodichnus, which exhibits distinctively weak mesaxony and a broader, transverse pes imprint with the ratio length < width, was identified in Korea, on the basis of material with suboptimal preservation. The trackmaker was a large ornithopod. Subsequently, in 2009 a second report recognized Ornithopodichnus in China, the trackmaker being a moderately large quadruped. In 2012, Ornithopodichnus was described on the basis of well-preserved material from the Upper Cretaceous of Korea, in this case left by a small, gregarious biped. Herein we document, a fourth occurrence of Ornithopodichnus in the Lower Cretaceous Feitianshan Formation of Sichuan, China which is a further exampl...

A dinosaur footprint assemblage from the Lower Jurassic Ziliujing Formation of Zigong City, Sichuan, China, comprises about 300 tracks of small tridactyl theropods and large sauropods preserved as concave epireliefs (natural molds). The theropod footprints show similarities with both the ichnogenera Grallator and Jialingpus. Three different morphotypes are present, probably related to different substrate conditions and extramorphological variation. A peculiar preservational feature in a morphotype that reflects a gracile trackmaker with extremely slender digits, is the presence of a convex epirelief that occurs at the bottom of the concave digit impressions. It is possibly the result of sediment compaction underweight load when the pes penetrated the substrate, being a resistant residue during exhumation and weathering. The sauropod tracks belong to a trackway with eight imprints consisting of poorly preserved pes and manus tracks and a better preserved set, probably all undertracks. The narrow-gauge trac...

Since 1858, when Hitchcock first recorded dinosaur tail traces from the Jurassic of Massachusetts, USA, a number of dinosaur tail traces have been reported. Although considered rare, at least 38 records of dinosaur tail traces have previously been reported in the literature. These occurrences are herein reviewed in order to understand their geographic and stratigraphic distribution, types of tail trace makers, and characteristics of dinosaur tail traces. Several terms for dinosaur tail traces have been employed and they are divided into tail impressions (TIs) for resting traces, and tail drag impressions (TDIs) for locomotion traces. Possible criteria for distinguishing, measuring and comparing TIs and TDIs are suggested. In addition, herringbone structures, one of the characteristic features of tail traces associated with ornithopod and theropod tracks, are discussed. Estimated speeds of tail trace makers are shown to be rather low. Finally, the abundance of tail traces associated with bipedal, rather th...

TriassictetrapodfootprintsfromChinaarelesswellknownthan those from the Jurassic and Cretaceous. Archosaurian trackways of the ichnogenus Chirotherium were found in the Middle Triassic Guanling Formation in Zhenfeng County (Guizhou Province) at the southwestern edge of the Yangtze plate in the early 1960s but were not correctly identified and adequately described until 40 years later. Here we give a detailed re-description and review of the trackways, which are known from two localities near the villages of Niuchang and Longchang. They occur on the bedding surface of a mud-cracked argillaceous dolostone deposited in a near-shore, shallow-water environment. Their morphology and general trackway pattern indicate that they pertain to the ichnospecies Chirotherium barthii, well known from Middle Triassic track surfaces of Europe, North and South America, and northern Africa. A peculiarity of the trackways from China are the low pace angulation and stride length, reflecting slow-moving trackmakers, which were basal crown-group archosaurs, possibly early representatives of the dinosaur-bird line or, alternatively, stem-group crocodylians. These tracks constitute the only chirotheriid record known from Asia thus far and indicate a Pangea-wide distribution for this ichnotaxon. Biostratigraphically, assemblages with C. barthii are characteristic of the early Anisian, an age assignment already supported for the Guanling Formation based on conodont andbivalvebiostratigraphy.Incontrast,however,radiometricdata from an interlayered ash bed indicate a Ladinian age.

Cenozoic bird tracks are known largely from North America, Europe, and the Middle East. There have been no reports of Cenozoic bird tracks from East Asia. This paper describes a series of two trackways produced by a galliform-like or gruiform-like bird from the Oligocene to Early Miocene of Tibet. The tracks are represented by tracings collected from a coal mine in Shigatse, Tibet, during the late 1970s. The tracks are comparable to Ornithoformipes and Pavoformipes and likely represent a medium-sized to large cursorial or flightless bird. In relation to modern bird tracks, the tracks bear a striking resemblance to those produced by the North American Wild Turkey (Meleagris gallopavo) except that M. gallopavo tracks often possess a small, elevated hallux impression. Due to the fact that these are tracings, however, a hallux may have been present and simply have been overlooked. The Shigatse trackways were, unfortunately, lost when the mine was closed and then backfilled during the 1980s, and there is littl...

Trackways of small (foot length ∼12–15 cm) robust ornithopods are relatively uncommon in the Cretaceous, where most tracks attributed to iguanodontids and hadrosaurs range in size from ∼20–80 cm. The Hwasun site, previously noted for its abundant theropod trackways, also reveals one horizon (L2) with at least six parallel trackways of small blunt-toed ornithopods with wide tracks, short steps and typical inward rotation of the pes. The site also reveals a second horizon (L4) which yields a single clear trackway of a much larger blunt-toed ornithopod. Although allometric trends in tridactyl track assemblages tend to show increased trackway width and reduced anterior projection of digit III (reduced mesaxonic emphasis) with increasing size, the small Hwasun ornithopods reveal unusually wide tracks with reduced mesaxony. The tracks are herein assigned to the ichnogenus Ornithopodichnus. A map of previously unmapped Level 4 is presented showing the context of the large ornithopod tracks on the same surface as...

At least six sites with multiple parallel ornithopod trackways and one site with three parallel sauropod trackways have been mapped in the track-rich Cretaceous sequence on Sado and Chudo islands, Yeosu City area, South Korea. A preliminary study of the stratigraphic context of these tracks indicates that they were made by gregarious subadult or adult dinosaurs that frequented lake basin settings subject to a cyclic depositional regime and periodic ash fall. Bird and theropod dinosaur tracks also occur in the sequence. Mapped sites reveal between 4 and 14 regularly spaced, ornithopod trackways suggestive of herding behavior. One site reveals an 84 m-long trackway, the longest on record for an ornithopod. Only one site reveals parallel sauropod trackways indicating three animals of equal size traveling eastwards with an inter-trackway spacing of about 2.25–2.5 m. The footprints show well preserved pes claw impressions, slightly wide gauge and large manus/pes ratios (low heteropody). The sedimentological an...

New didactyl dinosaur tracks from the fine-grained sandstone of the Early Cretaceous Jinju Formation, Namhae area, Korea, are herein described as Dromaeosauripus jinjuensis ichnosp. nov. A trackway about 4.3 m long is composed of 12 consecutive didactyl traces. The tracks average about 9.3 cm long and 6.8 cm wide. Pace, stride, and pace angulation are 40 cm, 80 cm, and 175°, respectively. D. jinjuensis is a small didactyl track characterized by slender digit impressions, very narrow divarication angle between digits III and IV, digit III slightly longer than IV, and sharp claw impressions. D. jinjuensis measurements differ significantly from D. hamanensis in length (only 60% of the latter), width (81%), length/width ratio (0.72), and digit thickness (55%). The didactyl tracks are tentatively interpreted to be formed by a small dromaeosaurid walking bipedally on a lake margin. D. jinjuensis represents the oldest theropod dinosaur tracks described in the Cretaceous of Korea and the second ichnospecies of Dr...

Cretaceous bird tracks assigned to the ichnogenera Aquatilavipes and Koreanaornis are reported for the first time from Sado Island in the Yeosu Island archipelago, Korea, an area already known for multiple dinosaur track-bearing horizons. The Koreanaornis tracks are associated with many small Cochlichnus trails attributed to nematode worms, on which the birds were likely feeding in a lake shoreline environment. The Koreanaornis and Aquatilavipes assemblages occur at different, albeit close, stratigraphic levels. The Aquatilavipes report is the first from Korea.

More than 2,500 well-preserved bird tracks associated with theropod and sauropod tracks are recorded from a dense assemblage in lacustrine deposits of the Early Cretaceous Haman Formation of the Gajin area, Jinju, Korea. These tracks are preserved in the recently constructed Fossil Heritage Hall at the Gyeongsangnamdo Institute of Science Education. Bird tracks are attributed to Ignotornis gajinensis ichnosp. nov., Koreanaornis hamanensis, Goseongornipes markjonesi, and ?Aquatilavipes. Like G. markjonesi, I. gajinensis is a semi-palmate bird track, similar to Hwangsanipes (ichnofamily Ignotornidae) with a postero medially directed hallux and characterized by interdigital angles between digits II and III larger than III and IV. However, Hwangsanipes is a larger morphotype than Ignotornis with a more pronounced semipalmate web. I. gajinensis has associated arcuate to semi-circular, double-grooved, or paired impressions resulting from spoonbill-like feeding behavior. Similar rare but more linear traces occur...

We review the status of the distinctive ichnogenus Minisauripus based on more than 80 well-preserved tracks comprising a minimum of 50 trackways from two localities in China and five in Korea. The tracks, attributed to theropod dinosaurs, have been assigned to two ichnospecies, M. chuanzhuensis and M. zhenshounani, based on Chinese specimens. Until recently, the known range of foot lengths was 1.5–6.0 cm, indicating a diminutive track-making species. However, newly discovered Minisauripus tracks from the Haman Formation in the Changseon region of Korea are as short as 1.0 cm. Most remarkably, a few, provisionally also labeled cf. Minisauripus, are reported as large as 16–20 cm, potentially adding unprecedented new data to the previous record. The larger tracks suggest that all the small tracks pertain to juveniles and not a small, distinct species as previously inferred. Tracks with foot lengths of only ∼1 cm suggest that individuals hatched from very small eggs. The fact that such tracks are abundant in ...

Trackways ascribed to Lithographus hieroglypichus and attributed to pterygote insects are described from the Cretaceous Uhangri Formation of Korea. The locality is part of the Haenam Tracksite at the Uhangri Dinosaur Museum Complex, which is famous for dinosaur, pterosaur and bird tracks. This represents the first report of the arthropod trackway Lithographus from the Cretaceous of Korea. The trackways are preserved in cherty mudstones that formed in the margins of an alkaline lake in the vicinity of active volcanoes. Numerous trackways are preserved at a single horizon. This probably reflects a brief period of exposure of balanced-fill lake margin sediments, which provided a window of opportunity for the production and preservation of trackways of insects that inhabited the region rather than a sudden influx of insects into the area related to volcanism and a productivity bloom.

Bird tracks are abundant and ubiquitous in many Cretaceous formations in Korea. To date, in order of discovery and description, the following six ichnogenera have been reported: Koreanaornis, Jindongornipes, Uhangrichnus, Hwangsanipes, Ignotornis, Goseongornipes and ?Aquatilavipes. As more bird tracks are discovered it has become possible to amend descriptions of existing ichnotaxa to better understand track morphology (and ichnotaxonomic relationships), trackway patterns and associated feeding traces and gain further insight into the behavior and ecology. We review and re-evaluate the most important bird tracksites in Korea, with special reference to sites not previously fully or adequately described in accessible English language journals. We pay special attention to material from the Uhangri Dinosaur Museum, Haenam area, and the Gyeongsangnamdo Institute of Science Education, Gajin area, presenting revised descriptions, illustrations and information on Uhangrichnus and Goseongornipes.

Enigmatic tracks and dinosaur trackways from lacustrine margin sediments of the Lower Cretaceous Haman Formation of the southern coast of Korea represent a new ichnospecies. Trackways with large, pes-only tracks with lengths up to 39 cm, characterized by elongate, subtriangular outlines, impressions of four digits and a subangular heel, are attributed to plantigrade pterodactyloids and assigned to Haenamichnus gainensis ichnosp. nov. These tracks comprise one of the largest and longest pterosaur trackways hitherto reported and provide intriguing new insight into pterosaur locomotory gait and stance, which has been the subject of a 200-year-long controversy. Associated sauropod tracks, assigned herein to Brontopodus birdi, reach 70 cm in length, are medium-gauged, and show outwardly curved digit impressions. E-W trackway alignments likely indicate shoreline trends but could possibly suggest behavioral hunting scenarios. Pes-only pterosaur tracks at this locality are another example of spoor incorrectly int...

We report the first occurrence of the trackway of a quadrupedal ornithopod from the Jindong Formation (Late Aptian) of Korea. Although trackways of ornithopods are abundant in the Cretaceous of Korea, especially in the Jindong Formation, trackways of a quadrupedal trackmaker have never been reported from Korea. Moreover, the manus shows an unusual morphology with three subcircular indentations arranged in an unusual, elongate arc unlike any seen in other ornithopod ichnospecies. The specimen is clearly different from all other known Korean ornithopod footprints and is herein named as Caririchnium kyoungsookimi. To date, Caririchnium is one of only two ichnogenus names applied with confidence to Lower Cretaceous ornithopod tracks from Asia.

New sauropod tracks are described herein as Brontopodus pentadactylus ichnosp. nov. from the Early Cretaceous Haman Formation of Jinju area, Korea. B. pentadactylus is characterized by a medium gauged trackway with wide pentadactyl manus tracks revealing hitherto unreported morphology. Thus, B. pentadactylus provides new insight into the morphology of the fleshed-out manus of sauropods showing that, unlike most semi-circular manus tracks that lack discrete digit traces, some indicate trackmakers with clearly differentiated, well-defined, and very wide manus digits. Manus tracks sometimes appear as tridactyl impressions that appear outwardly rotated at right angles to the midline of the trackway. This track morphology appears to reflect greater weight distribution on the outer, postero-lateral part of the manus. The pes is elongate, pentadactyl, outwardly rotated, and typical of Brontopodus. The manus pes heteropody ratio is about 1:2. These sauropod tracks are associated with thousands of bird footprints ...

Vertebrate tracks were first reported from the Cretaceous of South Korea in 1969 by B. K. Kim. His discovery of bird tracks, appropriately named Koreanaornis hamanensis, not only signaled the first bird tracks discovered in Asia and the second formally named avian ichnogenus from the Mesozoic, but it also was an indication of the vast wealth of vertebrate tracks that would be discovered a generation later in the Haman Formation and other Cretaceous formations of Korea, particularly in the large Gyeongsang Basin. This landslide of discovery has resulted in a proliferation of papers on vertebrate tracks from the Cretaceous of South Korea and the growing recognition that as a region it reveals multiple track-rich sequences of unique quality and scientific utility. Because of the outstanding ichnological resources in this region, it has been dubbed the Korean Cretaceous Dinosaur Coast (KCDC). Many sites of national and international significance have been designated as national natural landmarks, and the best...

Purported T. rex tracks (genus Tyrannosaurus) are rare and, if poorly preserved, difficult to identify or to distinguish with certainty from the tracks of hadrosaurs found in the same deposits. Six possible Tyrannosaurus tracks have been reported, five of which appear to be the right age, that is, Maastrichtian. However, at least two, including one that is pre-Maastrichtian, are interpreted as hadrosaur tracks.

In 1961, two human footprints were excavated from the Cuatro Cienegas region of Coahuila, Mexico, but for decades were not studied scientifically or deposited in any museum. Consequently, knowledge of the locality where they were found was lost. Once the two tracks were relocated they found their way to the Museo del Desierto, Saltillo (Coahuila) where they were placed on display with a tentative label suggesting an early Holocene age (10,000 B.C.). This inference was based only on the known antiquity of humans in the region determined from previous archaeological work and two dated sediment cores close to the footprint site. It was not until 2006 that the presumed footprint discovery site was rediscovered, revealing more than 20 additional well-preserved prints, in at least four trackways representing several different individuals with foot lengths ranging from about 23–27 cm. The tracks include one well-preserved trackway providing step and stride measurements. A poorly preserved cervid trackway and a p...

Observations were made on the preservation of modern human tracks in a salina near Cuatro Cienegas, Coahuila, Mexico. Track making potential is relatively high in such arid, ephemeral lake basin settings where salinas or alkali flats typically develop. However, because of the instability of evaporite minerals, long-term preservation potential of such tracks is compromised. The substrate in the study area is composed of a mixture of sand and a high percentage of sulfate crystals (gypsum, bloedite, epsomite). At the sediment-air interface, there is a thin white, crystalline sulfate crust that overlies the original track-bearing surface and prevents water loss. The size and surface growth of sulfate crystals in the crust is affected by the differential pressure caused by the track maker. Such tracks represent a good example of a biogenic process (track formation) affecting a physical sedimentological process.

Human tracks discovered in 1874 at a site named El Cauce or Acahualinca near the shores of Lake Managua, Nicaragua, are the most famous and abundant human tracks in the Americas. They represent a landmark ichnological discovery during the late 19th century that generated much debate regarding their age and origins. Reported dates for the tracks range from 2,120 to 6,500 B.P. The site, which is now situated within the limits of Nicaragua's capital city of Managua, forms the basis of the Acahualinca Tracks Museum (Huellas de Acahualinca) and has been in place since 1953. However, it is still little known and has not been systematically studied, despite being an important window into Meso-American prehistory. Two exposures of a surface of volcanic ash reveal hundreds of human tracks comprising a minimum of 12 clearly defined trackways, and a trampled zone or path representing at least three more individuals, all heading in the same northwesterly direction. Tracks of deer, opossum and at least one bird are al...

Pyroclastic sediments provide an unusual and favorable medium for the recording, burial, and preservation of tetrapod tracks and other traces. Twenty-two tracksites were reviewed for the purpose of determining how these deposits contribute to track formation, burial, and preservation. These include Jurassic sites in Argentina and Mexico, Cretaceous sites in Korea, Miocene sites in Mexico and the United States, Pliocene sites in Tanzania, Pleistocene sites in Mexico, Korea, and Italy, and Holocene sites in Mexico, Turkey, Italy, Japan, New Zealand, Nicaragua, and the United States. Twelve of the sites contain hominid tracks. Tracksites occur most commonly in reworked tephra on the shorelines of rivers, lakes, and seas. They also occur on pyroclastic falls, flows, and surges, and on lahars. Most tracksites are in volcanic arcs, especially around the Pacific Rim. A few occur in continental rifts or near intraplate volcanoes. Most older tracksites (Jurassic, Cretaceous, and Miocene) occur in silicic tephras s...

Only two vertebrate groups, humans and sauropod dinosaurs, have a well-developed entaxonic foot (with the big toe, or digit I, the largest), and both have vertical limbs. Thus, convergence applies not only to the feet but also to the limbs. When viewed in relation to their closest relatives among the hominoids and saurischian dinosaurs, and in the context of known developmental growth patterns in higher vertebrates, both humans and sauropod dinosaurs appear to be excellent examples of peramorphosis (specifically hypermorphosis). Thus, it is essential to understand morphodynamics as a field that is inseparable from the study of heterochrony. The morphodynamic developmental perspective, while recognized as important in genetics and embryology, has for many generations been overlooked in studies of feet, footprints and limbs (i.e., the marco-morphology of organs). Investigating these dynamics reveals striking recursive (or fractal) patterns of anterior-posterior and proximal distal development, which in turn...

Although more than 60 ancient hominid track sites ranging in age from 3.7 million to less than 500 B. P. are recorded from all continents except Antarctica, no ichnotaxonomic names have ever been formally proposed for hominid tracks. There is no prohibition to the naming of fossil footprints of species that created tracks and trackways similar to those of living species. On the contrary, there is precedent for the naming of ichnotaxa corresponding to the dominant extant vertebrates classes: mammals = Mammalipedia and birds = Avipeda. The hominid track site sample includes only about a dozen sites where footprint preservation is good enough to show details of diagnostic foot morphology and typical trackway morphology. We infer that the Acahualinca Footprint Museum site in Nicaragua represents the most important ancient hominid track site that combines accessibility, a large sample of well-preserved trackways and reliable dating. For this reason, we select the Nicaraguan tracks as the type sample for the ne...

Hominid footprints are particularly appealing and evocative of the living activity of our ancestors. The most famous and oldest (Late Pliocene, ca. 3.7 Ma) hominid footprints, from Laetoli in East Africa, have been attributed, with some uncertainly, to genus Homo or Australopithecus. The African track record also yields Early Pleistocene (∼1.5 Ma) tracks attributable to Homo erectus. The only well-documented Middle Pleistocene tracks (age ∼325,000-385,000 yrs) are reported from Italy and presumably represent a pre-Homo sapiens species. The oldest Late Pleistocene tracks (∼117,000 yrs), from southern Africa, may represent modern humans. However, the majority of Late Pleistocene sites are European, associated with caves in Romania, Greece, France and elsewhere, where hominid track preservation is often of high quality. Dates range from ∼10,000 to ∼62,000 BP Cavesite mammal tracks are almost exclusively those of carnivores, thus representing a distinctive underground ecology. Late Pleistocene open air sites ...

The type material of the ichnospecies Gigantosauropus asturiensis Mensink and Mertmann 1984 is re-examined and shown to represent a sauropod rather than a theropod. This interpretation confirms the recent suggestions of several authors. We describe the trackway in detail but conclude that it is not diagnostic at any taxonomic level, below the general category of sauropod. Thus, G. asturiensis may legitimately be considered a nomen dubium, and the name should be restricted to the original material and not extended to formally describe other poorly preserved specimens. Claims that the largest pes tracks are 1.35 or even 1.5 m in length are incorrect. Pes length ranges from 98–125 cm (mean 110.75 cm). Hispanosauropus hauboldi Mensink and Mertmann 1984 is also of doubtful utility as previously defined. The holotype, a field specimen, which clearly represents a theropod dinosaur, cannot be located, and may be lost to erosion. The paratype is a sauropod track and therefore has no relevance to the ichno-species ...

Until recently fossil footprints were virtually unknown from the Cretaceous of the eastern United States. The discovery of about 300 footprints in iron-rich siliciclastic facies of the Patuxent Formation (Potomac Group) of Aptian age is undoubtedly one of the most significant Early Cretaceous track discoveries since the Paluxy track discoveries in Texas in the 1930s. The Patuxent tracks include theropod, sauropod, ankylosaur and ornithopod dinosaur footprints, pterosaur tracks, and miscellaneous mammal and other vertebrate ichnites that collectively suggest a diversity of about 14 morphotypes. This is about twice the previous maximum estimate for any known Early Cretaceous vertebrate ichnofauna. Among the more distinctive forms are excellent examples of hypsilophodontid tracks and a surprisingly large mammal footprint. A remarkable feature of the Patuxent track assemblage is the high proportion of small tracks indicative of hatchlings, independently verified by the discovery of a hatchling-sized dinosaur....

Invertebrate and vertebrate (tetrapod) ichnology have evolved as separate disciplines, largely due to differences in the morphology and behavior of the tracemakers and the practical impossibility of treating them as uniform subjects of analysis. Thus, invertebrate ichnotaxa reflect behavior to a much greater degree than they reflect tracemaker morphology. The situation is essentially reversed in the case of vertebrates, where morphology, especially of the foot, plays an important primary role in ichnotaxonomy (and a secondary role in trackmaker identification), whereas behavior is of much lesser importance and in many cases can compromise consistent and effective ichnotaxonomy. Inherent differences in morphological and behavioral complexity also have significant implications for our concept of the different potentials of vertebrate and invertebrate ichnotaxonomy and ichnofacies analysis—as shown in distinctions made between biotaxonichnofacies and ethoichnofacies, respectively. Vertebrate tracks not only ...

Some small and medium-sized crocodylomorph footprints are described from the Late Jurassic (Kimmeridgian) coastal and deltaic units of the northern Spain (Asturias). There are at least four footprint morphotypes. Three of them, with well preserved trackways, are included in the ichnogenus Crocodylopodus (Crocodylopodus isp. and Crocodylopodus meijidei); the fourth one, documented by some isolated large footprints, is referable to the ichnogenus Hatcherichnus. This ichnoassociation confirms the presence of small crocodilians in palaeoenvironments apparently dominated by dinosaurs. The presence of Hatcherichnus seems to confirm the affinity between the Iberian and North American ichnofaunas.

New discoveries show that very small theropod tracks (cf. Wildeichnus) are abundant in the upper part of the Moab Member, recently assigned to the Curtis Formation (formerly considered part of the Entrada Formation) in the Mid-?Late Jurassic of eastern Utah. The tracks represent a distinct small-theropod ichnofacies associated with eolian dune deposits that is easily differentiated from the water-lain beds of the overlying Megalosauripus-Therangospodus ichnofacies, which comprises the single-surface Moab megatracksite. Pterosaur track assemblages, representing the Pteriachnus ichnofacies, are found a few meters above the megatracksite surface in the upper tongue of the Summerville Formation. The small theropod ichnofacies is reminiscent of other early Mesozoic dune facies ichnofaunas from the Wingate and Navajo formations (Late Triassic and Early Jurassic) where small theropod tracks occur in association with other small tetrapod footprints. All such examples evidently represent a recurrent dune facies ec...

Remnants of Bushmen cave paintings showing representations of dinosaurs evidently reconstructed from footprints, trackways and skeletal remains have been found in Lesotho. This is a region of prolific dinosaur trackways preserved in Lower Jurassic sedimentary rocks, and the Bushman culture is renowned for extraordinary skill in the tracking of modern animals. It is probable that the track and trackmaker representations depict ornithopod dinosaurs. The track drawings are accurate, and the trackmaker representations show that Bushman artists anticipated modern reconstructions of bipedal dinosaurs and produced depictions that are more realistic than many paleontological reconstructions that endured until quite recently.

Nine dinosaur ichnospecies from the Lower Jurassic to Upper Cretaceous of Japan, including two that are new, are described herein. The new ichnotaxa are Asianopodus pulvinicalx ichnogen. et ichnosp. nov. and Schizograllator otariensis ichnosp. nov. The Japanese ichnotaxa are allied to Lower Jurassic ichnospecies in South China, North America, Western Europe and South Africa, and Upper Jurassic to Lower Cretaceous ichnospecies from Southeast and East Asia. This suggests they were part of a global ichnofauna before continental drift began in the Middle Jurassic, leading to the development of a more endemic dinosaur fauna in the Cretaceous. At least two assemblages, an ornithopod-gracile-toed theropod-dominated community, in northeastern Asia, and a robust theropod- and sauropod-dominated community in the southern part of the continent, existed in the Cretaceous. This parallels North American dinosaur distribution patterns in the Cretaceous and seems to be a reflection of paleolatitudinal controls.