Fossil trackway

A fossil trackway is a type of fossil impression, a trackway made by a once living organism, usually by its feet. The majority of known fossil trackways are made by fossil dinosauria, or tetrapods, or bipeds. However other animal species also make trackways, for example ocean bottom-dwelling creatures.

An example of a water genus is the Sea scorpion genus Hibbertopterus.

The majority of fossil trackways will be foot impressions on land, or subsurface water, but other types of creatures will leave their distinctive species impressions. Examples of creatures supported, or partially supported, in a water environment are known. The fossil "millipede-type" genus Arthropleura left its multilegged/feet trackways on land.

Some basic fossil trackway types:
 * footprints
 * tail drags
 * belly drag marks-(tetrapods)
 * chain of trace platforms–(example: Yorgia)
 * body imprint-(Monuran trackway, insect)

Notable trackways
The foremost example of the human species trackway, is the 3.7 mya Laetoli footprints of Tanzania. The trackway is now in preservetion under a protective layer of earth.

Tetrapod trackways
The earliest land creatures, (actually land-marine coastal-riverine-marshland) left some of the first trackways. They range from tetrapods to proto-reptilians and others.

The Permo-Carboniferous of Prince Edward Island contains trackways of tetrapods and stem-reptiles. Macrofloral, and palynological data help correlate timeframes. Some new ichnofossils are recorded from this geologic sequence.

Ireland contains Late Devonian tetrapod trackways from the Valentia Slate Formation. (The article discusses the history of the tetrapods, lobe-finned fish, and the ray-finned fish-(the later teleosts).

Dinosaur trackways
Dinosaurs lived on the continents when the plant grasses had not evolved-(the "Age of the Grasses" evolved with the "Age of the Mammals"); the dinosaurs lived from the Triassic, Jurassic, and Cretaceous and left their trackways, both the plant-eaters and the meat-eaters in various layers of mud, sand, etc later to become stone.

Central North America was one notable trackway location because of the Interior Seaway, but all of North America, and regions of South America left fossil trackway layers.

With scientific analysis, dinosaur specialists are now analyzing tracks for the walking-speeds, or sprint-running speeds for all categories of dinosaurs, even to the large plant eaters, but especially the faster 3-toed meat hunters. Evidence of herding, as well as pack hunting are also being investigated.

Dinosaur trackways in Africa
An example trackway from Africa is a trackway in 140 ma rose-colored sandstone of Chewore Area, Lower Zimbabwe Rift Valley. The small footprint size, with both manus and pes implies that it is a trackway of a juvenile, a probable carnosaur.

Dinosaur trackways in the Americas
The western regions of North America, and sometimes the western border of the Interior Seaway are common for dinosaur trackways. Wyoming has dinosaur trackways from the late cretaceous, 65 ma. (A model example of this 3-toed Wyoming trackway was made for presentation.)

North America trackways
The Great Plains has trackway sites in the north from Nebraska to Montana, USA. Some notable areas have numerous tracks in advanced states of erosion that extend for miles with breaks in between intersecting drainage areas, the trackways continuing on the opposite sides of the drainages.

Australia trackways
A recent marsupial trackway site in the Colac dstrict of Australia, (west of Colac) contains marsupial trackways, as well as kangaroo and wallaby tracks.

Mammal trackways
Mammal trackways are one of the least common trackways, and are in the 'Age of the Grasses', 'Age of the Mammals'. Mammals were not often in mud, or riverine environments, more often in the forestlands, or grasslands. Thus the earlier tetrapods or proto-tetrapods would yield the most fossil trackways, from these 4-footed creatures. The Walchia forest of Brule, Nova Scotia has an example of an in situ Walchia forest, and tetrapod trackways that extended over some period of time through the forest area.