A trace fossil, also known as an ichnofossil, is a fossil record of biological activity but not the preserved remains of the plant or animal itself. Trace fossils contrast with body fossils, which are the fossilized remains of parts of organisms' bodies, usually altered by later chemical activity or mineralization. The study of such trace fossils is ichnology and is the work of ichnologists.
Dilophosaurus is a genus of theropod dinosaurs that lived in what is now North America during the Early Jurassic, about 193 million years ago. Three skeletons were discovered in northern Arizona in 1940, and the two best preserved were collected in 1942. The most complete specimen became the holotype of a new species in the genus Megalosaurus, named M. wetherilli by Samuel P. Welles in 1954. Welles found a larger skeleton belonging to the same species in 1964. Realizing it bore crests on its skull, he assigned the species to the new genus Dilophosaurus in 1970, as Dilophosaurus wetherilli. The genus name means "two-crested lizard", and the species name honors John Wetherill, a Navajo councilor. Further specimens have since been found, including an infant. Footprints have also been attributed to the animal, including resting traces. Another species, Dilophosaurus sinensis from China, was named in 1993, but was later found to belong to the genus Sinosaurus.
Edward Hitchcock was an American geologist and the third President of Amherst College (1845–1854).
Anchisaurus is a genus of basal sauropodomorph dinosaur. It lived during the Early Jurassic Period, and its fossils have been found in the red sandstone of the Portland Formation, Northeastern United States, which was deposited from the Hettangian age into the Sinemurian age, between about 200 and 195 million years ago. Until recently it was classed as a member of Prosauropoda. The genus name Anchisaurus comes from the Greek αγχιanchi-; "near, close" + Greek σαυρος ; "lizard". Anchisaurus was coined as a replacement name for "Amphisaurus", which was itself a replacement name for Hitchcock's "Megadactylus", both of which had already been used for other animals.
Opisthocoelicaudia is a genus of sauropod dinosaur of the Late Cretaceous Period discovered in the Gobi Desert of Mongolia. The type species is Opisthocoelicaudia skarzynskii. A well-preserved skeleton lacking only the head and neck was unearthed in 1965 by Polish and Mongolian scientists, making Opisthocoelicaudia one of the best known sauropods from the Late Cretaceous. Tooth marks on this skeleton indicate that large carnivorous dinosaurs had fed on the carcass and possibly had carried away the now-missing parts. To date, only two additional, much less complete specimens are known, including part of a shoulder and a fragmentary tail. A relatively small sauropod, Opisthocoelicaudia measured about 11.4–13 m (37–43 ft) in length. Like other sauropods, it would have been characterised by a small head sitting on a very long neck and a barrel shaped trunk carried by four column-like legs. The name Opisthocoelicaudia means "posterior cavity tail", alluding to the unusual, opisthocoel condition of the anterior tail vertebrae that were concave on their posterior sides. This and other skeletal features lead researchers to propose that Opisthocoelicaudia was able to rear on its hindlegs.
Grallator ["GRA-luh-tor"] is an ichnogenus which covers a common type of small, three-toed print made by a variety of bipedal theropod dinosaurs. Grallator-type footprints have been found in formations dating from the Early Triassic through to the early Cretaceous periods. They are found in the United States, Canada, Europe, Australia, Brazil and China, but are most abundant on the east coast of North America, especially the Triassic and Early Jurassic formations of the northern part of the Newark Supergroup. The name Grallator translates into "stilt walker", although the actual length and form of the trackmaking legs varied by species, usually unidentified. The related term "Grallae" is an ancient name for the presumed group of long-legged wading birds, such as storks and herons. These footprints were given this name by their discoverer, Edward Hitchcock, in 1858.
A fossil track or ichnite is a fossilized footprint. This is a type of trace fossil. A fossil trackway is a sequence of fossil tracks left by a single organism. Over the years, many ichnites have been found, around the world, giving important clues about the behaviour of the animals that made them. For instance, multiple ichnites of a single species, close together, suggest 'herd' or 'pack' behaviour of that species.
The Connecticut River Valley trackways are the fossilised footprints of a number of Early Jurassic dinosaurs or other archosauromorphs from the sandstone beds of Massachusetts and Connecticut. The finding has the distinction of being among the first known discoveries of dinosaur remains in North America.
Eubrontes is the name of fossilised dinosaur footprints dating from the Late Triassic and Early Jurassic. They have been identified from France, Poland, Slovakia, Czech Republic, Italy, Spain, Sweden, Australia (Queensland), USA, India and China.
Dinosaur State Park and Arboretum is a state-owned natural history preserve occupying 80 acres (32 ha) in the town of Rocky Hill, Connecticut. The state park protects one of the largest dinosaur track sites in North America. The park was created in recognition of fossil trackways embedded in sandstone from the beginning of the Jurassic period, about 200 million years ago. The facility is managed by the Connecticut Department of Energy and Environmental Protection.
The Hitchcock Ichnological Cabinet is a collection of fossil footmarks assembled between 1836 and 1865 by Edward Hitchcock (1793–1864), noted American geologist, state geologist of Massachusetts, United States, and President of Amherst College. He was one of the first experts in fossil tracks. A footmark impression in stone is a petrosomatoglyph.
Otozoum is an extinct ichnospecies of fossilized sauropodomorph dinosaur footprints and other markings in sandstones. They were made by heavy, bipedal animals with a short stride that walked on four toes directed forward.
Dinosaur Footprints in Holyoke, Massachusetts, USA is an 8-acre (3 ha) wilderness reservation purchased for the public in 1935 by The Trustees of Reservations. The Reservation is currently being managed with the assistance from the Massachusetts Department of Conservation and Recreation (DCR). The fossil and plant resources on the adjacent Holyoke Gas and Electric (HG&E) riverfront property are being managed cooperatively by The Trustees, Mass DCR, and HG&E.
Stegomosuchus is an extinct genus of small protosuchian crocodylomorph. It is known from a single incomplete specimen discovered in the late 19th century in Lower Jurassic rocks of south-central Massachusetts, United States. It was originally thought to be a species of Stegomus, an aetosaur, but was eventually shown to be related to Protosuchus and thus closer to the ancestry of crocodilians. Stegomosuchus is also regarded as a candidate for the maker of at least some of the tracks named Batrachopus in the Connecticut River Valley.
Argoides is an ichnogenus of dinosaur footprint, originally named as an ichnospecies of Ornithichnites, left by what was possibly an ornithopod, although due to the age of the tracks, they were probably instead made by theropods. A 2.8 cm long footprint from the lower Jurassic represents the holotype. The size of the track maker is estimated at 56 cm (1.84 ft) long and 185 grams (0.408 lbs) in weight. It has been found in the Portland, Passaic and Turners Falls Formations of Massachusetts, Connecticut and New Jersey.
Sauroidichnites is an ichnotaxon of saurian reptiles. The name was originally used by Edward Hitchcock as a higher group name rather than a specific ichnogenus, and thus the name does not have priority over specific ichnogenus names even if they were first identified as Sauroidichnites.
Paleontology in Connecticut refers to paleontological research occurring within or conducted by people from the U.S. state of Connecticut. Apart from its famous dinosaur tracks, the fossil record in Connecticut is relatively sparse. The oldest known fossils in Connecticut date back to the Triassic period. At the time, Pangaea was beginning to divide and local rift valleys became massive lakes. A wide variety of vegetation, invertebrates and reptiles are known from Triassic Connecticut. During the Early Jurassic local dinosaurs left behind an abundance of footprints that would later fossilize.
Paleontology in Massachusetts refers to paleontological research occurring within or conducted by people from the U.S. state of Massachusetts. The fossil record of Massachusetts is very similar to that of neighboring Connecticut. During the early part of the Paleozoic era, Massachusetts was covered by a warm shallow sea, where brachiopods and trilobites would come to live. No Carboniferous or Permian fossils are known from the state. During the Cretaceous period the area now occupied by the Elizabeth Islands and Martha's Vineyard were a coastal plain vegetated by flowers and pine trees at the edge of a shallow sea. No rocks are known of Paleogene or early Neogene age in the state, but during the Pleistocene evidence indicates that the state was subject to glacial activity and home to mastodons. The local fossil theropod footprints of Massachusetts may have been at least a partial inspiration for the Tuscarora legend of the Mosquito Monster or Great Mosquito in New York. Local fossils had already caught the attention of scientists by 1802 when dinosaur footprints were discovered in the state. Other notable discoveries include some of the first known fossil of primitive sauropodomorphs and Podokesaurus. Dinosaur tracks are the Massachusetts state fossil.
Megapnosaurus is an extinct genus of coelophysid theropod dinosaur that lived approximately 188 million years ago during the early part of the Jurassic Period in what is now Africa. The species was a small to medium-sized, lightly built, ground-dwelling, bipedal carnivore, that could grow up to 2.2 m (7.2 ft) long and weigh up to 13 kg (29 lb). It was originally given the genus name Syntarsus, but that name was later determined to be preoccupied by a beetle. The species was subsequently given a new genus name, Megapnosaurus, by Ivie, Ślipiński & Węgrzynowicz in 2001. Some studies have classified it as a species within the genus Coelophysis, but this interpretation has been challenged by more subsequent studies and the genus is now considered valid.
The 19th century in ichnology refers to advances made between the years 1800 and 1899 in the scientific study of trace fossils, the preserved record of the behavior and physiological processes of ancient life forms, especially fossil footprints. The 19th century was notably the first century in which fossil footprints received scholarly attention. British paleontologist William Buckland performed the first true scientific research on the subject during the early 1830s.
