Paleontology in New Mexico
[2] During the early Paleozoic, southern and western New Mexico were submerged by a warm shallow sea that would come to be home to creatures including brachiopods, bryozoans, cartilaginous fishes, corals, graptolites, nautiloids, placoderms, and trilobites.
Triassic New Mexico had a seasonal climate and was home to a richly vegetated flood plain where early dinosaurs such as Coelophysis lived.
During the Jurassic New Mexico had a relatively dry climate and was home to dinosaurs such as Allosaurus, Stegosaurus, and the huge long-necked sauropods.
Local wildlife included creatures such as amblypods, carnivorans, condylarths, the 7-foot tall flightless bird Diatryma, three-toed horses, marsupials, multituberculates, and taeniodonts.
[5] Marine life included more than 157 species of brachiopods, 41 bryozoans, 34 cephalopods, 34 corals, 118 foraminiferans, 87 gastropods, 25 ostracods and 85 pelecypods.
At this time a huge reef system began to form at El Capitan in the southeastern part of the state.
220 million years ago, during the Late Triassic deposition of the Dockum Group, eastern New Mexico was a basin receiving sediments carried downhill by streams and rivers.
These sediments were probably trapped locally, burying the remains that would compose the area's fossil record, instead of making their way to the sea.
[14] On land a diverse flora grew that included at least 14 different kinds of fern, 16 figs, 8 honeysuckles, 5 willows, and trees that left behind petrified logs more than 30 feet long.
At the time the Dakota Formation was being deposited in northeastern New Mexico, more than 500 dinosaur tracks were imprinted in the sediments of Clayton Lake State Park.
[15] Geologic upheaval during the early Cenozoic era formed the state's basin and range physiographic province.
[16] Very few identifiable fossils have been discovered in New Mexican Oligocene deposits, so this epoch of time remains mysterious to paleontologists.
[3] During the Pleistocene epoch, large trees, probably pines, were preserved as impressions left in ancient San Jose Valley lava flows.
[3] American mastodon remains were found on the east slope of the Sandia Mountains at an elevation of 8,470 feet, the highest ever recorded for the species.
[16] The Jicarilla Apaches in southern New Mexico told a myth about the origin of fire that also served to explain the existence of petrified wood.
[21] The first record of fossils in New Mexico was written by Santa Fe Trader Josiah Gregg, who described local petrified wood in his 1846 book Commerce of the Prairies .
Other discoveries Cope made during his stay included camels, crocodiles, deer, dogs, horses, and mastodon remains.
[23] The Puerco Formation was discovered in 1875 but significant numbers of fossils were not described until David Baldwin's 1881 expedition on behalf of Edward Drinker Cope.
[6] In 1928, three boys discovered a completely articulated partial mummy of the ground sloth Nothrotherium shasetnse 100 feet below the surface of Aden Crater southwest of Las Cruces.
At a small stream roughly 16 miles south of Lamy, the couple noticed some fragments of fossil amphibian bones.
Traveling upstream to the source of the bones, the couple discovered a nearly solid mass of Triassic amphibian skeletons.
[26] In 1937 a crew working on road construction in Black Water Draw uncovered mammoth and bison remains associated with human artifacts.
They determined that the deposit preserving the amphibians was roughly fifty feet wide and extended a significant distance back into the hills.
Among the specimens were about 50 skulls many individual bones from their limbs and vertebral columns as well as armored plates that would protected the amphibians' shoulder region in life.
To protect the fragile fossils the block was given a cast made of 600 pounds of plaster, which was reinforced with iron, wood, and burlap until it weighed more than a ton.
[27] In 1947, an American Museum field party led by Edwin Harris Colbert discovered a bonebed including the skeletons of more than 1,000 Coelophysis at Ghost Ranch.
[28] Later, in 1953 University of New Mexico graduate student William Chenoweth discovered three important sites where dinosaurs were preserved in Morrison Formation rocks.
The team excavated a massive quarry and gradually recovered a significant portion of the rear half of a diplodocid sauropod dinosaur.
Fossils recovered included a huge allosaurid that may be referrable to the genus Saurophaganax, Camarasaurus, and the skull and teeth of a diplodocid.
Prior to these discoveries most dinosaur fossils discovered in New Mexico were scrappy remains uncovered serenipitously by mining operations and surveys for uranium.
