page_title: 20th century in ichnology
section_title: 1900s
hierarchical_section_title: 20th century in ichnology / 1900s
caption_attribution_description: English: Ipolytarnoc 8 million year old fossilized Pannonian Sea Coast with footsteps of ancient animals
context_page_description: The 20th century in ichnology refers to advances made between the years 1900 and 1999 in the scientific study of trace fossils, the preserved record of the behavior and physiological processes of ancient life forms, especially fossil footprints. Significant fossil trackway discoveries began almost immediately after the start of the 20th century with the 1900 discovery at Ipolytarnoc, Hungary of a wide variety of bird and mammal footprints left behind during the early Miocene. Not long after, fossil Iguanodon footprints were discovered in Sussex, England, a discovery that probably served as the inspiration for Sir Arthur Conan Doyle's The Lost World.
  Several enduring mysteries from the 19th century continued to vex ichnologists, like the identity of the Chirotherium trackmaker. Renowned paleontologist Franz von Nopcsa attributed the ichnogenus to the prosauropod dinosaur Plateosaurus, despite an apparent mismatch between its number of toes and the preserved digit traces of Chirotherium. Von Nopcsa explained the discrepancy by arguing that one of the impressions in the Chirotherium tracks was left by a soft tissue structure that did not fossilize.
context_section_description: 1900
  A major Lower Miocene fossil footprint site was discovered at Ipolytarnoc, Hungary. The site preserves more than 1600 individual footprints from a variety of birds and mammals. Avian ichnogenera at the site include Aviadactyla, Ornithotarnocia, Passeripeda, and Tetraornithopedia. Mammalian ichnogenera include Bestiopeda, Carnivoripeda, Megapecoripeda, Mustelipeda, Pecoripeda, Rhinoceripeda. These mammal tracks were left by creatures like carnivorans, peccaries, and rhinoceros. Mastodon tracks have also been reported, but may represent misidentifications.
  1902
  Dinosaur footprints were discovered at Fisher's Quarry, near Graterford, Pennsylvania. These tracks are now classified in the ichogenus Atreipus.
  1903
  John Bell Hatcher reported probable crocodilian footprints from the Morrison Formation near Canon City, Colorado.
  1904
  Richard Swann Lull began studying the Connecticut Valley footprints. He described the new ichnogenus Anchisauripus, named such because he attributed it to the early sauropod-precursor Anchisaurus.
  1905
  Luis Dollo matched the foot of Iguanodon bernissartensis with a purported Iguanodon footprint in "the first attempt to match these tracks with a particular species of the genus".
  1906
  Pleistocene human footprints were discovered in the Niaux cave complex of France.
  1908
  Paleocene fossil amphibian footprints were discovered in the Fort Union Formation of Montana.
  1909
  Harold Broderick described the three-toed Middle Jurassic dinosaur footprints that had first been discovered during the 1890s at England's Yorkshire coast.
  Fossil Iguanodon footprints were discovered in the rocks of the Wealden Beds at Crowborough, Sussex. These tracks may have inspired Sir Arthur Conan Doyle to write The Lost World.
caption: Fossil footprints at Ipolytarnoc
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