New Mexico to the Bone

The state’s history, seen through a paleo lens

The early meat-eating dinosaur Coelophysis is New Mexico’s Official State Fossil, by act of the Legislature in 1980. It is known from hundreds of exquisitely preserved skeletons found in 1947 at Ghost Ranch in Rio Arriba County. Photograph courtesy of the New Mexico Museum of Natural History.

New Mexico has long been world-famous  as a place where people have made many important dinosaur discoveries. Fossils from our state have helped paleontologists learn much about dinosaurs, including how they evolved, how they lived, and how they became extinct.

Furthermore, the history of dinosaur paleontology in New Mexico and the state’s history are woven together.


Native peoples discovered fossils in New Mexico long before the arrival of Europeans. Some of these fossils have been found in pueblos, such as at Gran Quivira in Torrance County. However, we have no knowledge of what significance these peoples attributed to the fossils. Some scholars contend that three-toed theropod dinosaur footprints resemble the avian tracks seen in some Paleoindian petroglyphs and pictographs. The Towa name for a site near Jemez Pueblo is Gee-tow-ta-own-lay-new, meaning “Place where the giant stepped.”

Paleontology (the study of ancient life) began in Western Europe during the early 1800s. Naturalists soon began to study fossils in the United States, and by the 1840s, various travelers and members of military expeditions began to discover fossils in the American West.

In 1929, a Smithsonian expedition headed by Charles Gilmore discovered and excavated this tail of a duckbill dinosaur in northwestern New Mexico. The tools in the photograph are testimony to how little the technology of collecting dinosaur fossils has changed in over a century. Courtesy of Smithsonian Institution, Natural History Museum, Paleobiology Department.
In the 1880s, Philadelphia-based paleontologist Edward Drinker Cope published the first scientific descriptions of dinosaur fossils from New Mexico; this illustration appeared in The Scientific Monthly in 1875.
The early meat-eating dinosaur Coelophysis is New Mexico’s Official State Fossil, by act of the Legislature in 1980. It is known from hundreds of exquisitely preserved skeletons found in 1947 at Ghost Ranch in Rio Arriba County. Photograph courtesy of the New Mexico Museum of Natural History.
The skull of the armored dinosaur Ziapelta found in northwestern New Mexico is covered with bony plates and has four horns toward the back of the skull. Described in 2014, Ziapelta is one of New Mexico’s most recently discovered new dinosaurs. Photograph by Spencer Lucas.

Josiah Gregg, the famous Santa Fe trader, first published a reference to a fossil in New Mexico in his 1844 book Commerce of the Prairies, mentioning petrified logs near Cerrillos in Santa Fe County. Gregg had made his initial trip from Missouri to Santa Fe in 1831 with a merchant caravan over the Santa Fe Trail. His arrival coincided with the first administration of Governor Manuel Armijo, who served three terms under Mexican rule. During the next decade, Gregg traversed the prairie from Missouri to New Mexico multiple times, continuing his journeys down into Mexico on the Chihuahua Trail.

In August 1846, Brigadier General Stephen Watts Kearny led the U.S. occupation of New Mexico. One month later, Charles Bent became the civilian governor of New Mexico, which remained under military rule. In January 1847, Governor Bent died during an uprising at Taos Pueblo in opposition to the US government, which resulted in a tragic massacre of more than 150 people.

US military expeditions of the late 1840s and 1850s brought to light more New Mexican fossils. Swiss paleontologist Jules Marcou accompanied Captain Amiel Weeks Whipple’s 1853 expedition seeking railroad routes and resources between Fort Smith, Arkansas, and San Diego, California. He found a Cretaceous (about 80 million year old; the Cretaceous Period was about 65 to 145 million years ago) shark’s tooth from near Galisteo in Santa Fe County, and named the extinct shark represented by this tooth Ptychodus whipplei, the first species named for a New Mexican fossil.

The Compromise of 1850 created the territories of Utah and New Mexico and dismissed Texas’s claims to the eastern half of New Mexico, which is the home of important sites of interest to paleontologists. Sediments at present-day Clayton Lake State Park preserve about 400 dinosaur tracks. The Mosquero Site south of Clayton Lake contains trackways left by ornithopod dinosaurs that moved through the area in the Cretaceous Period.

In 1854, the United States ambassador to Mexico, James Gadsden, negotiated with Mexican president Antonio López de Santa Anna for the purchase of 29,670 square miles of land for $10 million. This acquisition gave southwestern New Mexico its distinctive bootheel, and encompassed much of what became southern Arizona. Caves in the bootheel of New Mexico have yielded fossils of Stock’s vampire bat (Desmodus stocki), an extinct species that was larger than the living common species of vampire bats.

In January 1864, Major General James H. Carleton had enlisted Colonel Christopher “Kit” Carson to wage a scorched-earth campaign against Navajos living in their traditional lands in northeastern Arizona and northwestern New Mexico. That spring, the Army began a forced relocation of the Navajos to Fort Sumner in the Pecos River Valley. Several hundred perished along the route, but more than 8,000 Navajos who survived the trek of some 300 miles were confined at Bosque Redondo with about 400 Mescalero Apaches. By the end of the American Civil War, the military campaigns to subdue the Native peoples in New Mexico, as well as the war itself, opened New Mexico up to further exploration. Much of this exploration aimed to assess its natural resources, including those of a geological nature, such as coal and building stone. To make these assessments, geologists, including paleontologists, came to the territory.

The first American dinosaur fossils were unearthed in the early 1800s, but the first New Mexican dinosaurs that we now know of were not scientifically reported until the 1880s. Legendary fossil collector David Baldwin found New Mexico’s first dinosaur fossils. Born in Ohio, after the Civil War Baldwin moved west and began collecting fossils in New Mexico in 1876 for Yale University paleontologist Othniel Charles Marsh (1831–1899). Marsh was disappointed with the quality of the fossils that Baldwin found, and in 1881 stopped paying him. Baldwin then began collecting fossils for Marsh’s rival, Edward Drinker Cope (1840–1897), one of the first great American paleontologists.

In 1881, Baldwin collected a handful of fossil bones in the red and gray Triassic (210-million-year-old) rocks north of Abiquiú. He shipped them to Cope in Philadelphia, who identified them as the bones of a small, meat-eating dinosaur that he later (in 1889) named Coelophysis (see-low-FY-sis). Sometime in the 1880s, Baldwin also discovered fragmentary dinosaur bones in northwestern New Mexico in Cretaceous rocks (about 75 million years old), and Cope described them.

In 1878, two years after Baldwin began collecting fossils in New Mexico, the railroad pushed into the territory at Raton Pass. The Atchison, Topeka and Santa Fe (AT&SF) Railway had won a hard-fought competition against the Denver & Rio Grande Western Railroad for the best route into New Mexico from Colorado. By 1881, the AT&SF met the Southern Pacific at Deming to complete the second transcontinental rail route in the United States.

The railroad transformed New Mexico. Along the rapidly expanding rail system, towns sprung up where none had existed. Because of the ease of transportation of products to market, mining—especially of coal—exploded, as did the cattle industry. The Bureau of Immigration drew people to New Mexico from the eastern U.S., and the railroad facilitated their travel. From 1880 to 1910, the population more than tripled, from 120,000 to 327,000. The railroad was a godsend for paleontologists working in New Mexico because construction of railroad routes led to significant fossil discoveries, and railroads made it possible to safely transport large dinosaur fossils to scientific institutions back East.

One such institution was the American Museum of Natural History in New York City. Paleontologist Barnum Brown spent much of his career collecting dinosaurs and other fossils (including the original skeleton of Tyrannosaurus rex) for that institution. Brown went to northwestern New Mexico in 1904, partly following up on Baldwin’s original discoveries, but mostly pursuing the lead of George H. Pepper, a member of the Hyde Exploring Party, who reported dinosaur fossils from the area. Brown’s search took him directly to Ojo Alamo, a remote spring and (then) trading post, where he prospected the badlands. Here in 1901, Brown discovered the nearly complete skull of a duck-billed dinosaur he named Kritosaurus navajovius, the first Cretaceous dinosaur fossil from New Mexico to receive a scientific name.


By the time Brown went to the San Juan Basin, New Mexico had been a territory struggling to attain statehood for fifty-four years. Attempts to create a constitution had failed in 1850, 1872, and 1889. Statehood bills introduced in Congress in 1876 and 1902 had also failed. Statehood seemed attainable in 1906, when the New Mexico and Arizona territories held a referendum on the issue. New Mexico voted in favor, but Arizona voted the measure down. New Mexico persevered, and in June 1911, President William Howard Taft signed the Enabling Act. That November, delegates gathered in Santa Fe to draft a constitution, which voters approved on January 6, 1911. The following January, Taft signed the document proclaiming statehood.

Statehood provided further impetus to develop the economic resources of New Mexico. This brought John Reeside to northwestern New Mexico from 1915 to 1923, where he mapped the coal-bearing rocks and related formations for the US Geological Survey. Reeside’s fieldwork brought forth many fossils, most notably the bones of a sauropod (brontosaur) he discovered near Ojo Alamo in 1921. Named Alamosaurus sanjuanensis, these fossils provided the first evidence that sauropod dinosaurs lived in North America until nearly the end of the Cretaceous Period, when all dinosaurs became extinct.

While Reeside mapped, on March 9, 1916, Pancho Villa and almost 500 of his men attacked the community of Columbus, New Mexico. In retaliation, General John J. Pershing led the Punitive Expedition on a six-month chase after Villa through northern Mexico, deploying airplanes and trucks for the first time. With the United States’ entry into World War I looming in January 1917, the troops withdrew from Mexico without capturing Villa.

In the fall of 1918, despite the improved sanitation and medical care that came with scientific interest in the state, and a large military presence, the Spanish Flu struck New Mexico. Out of a population of around 360,000, 50,000 cases of influenza were reported. The exact number of fatalities is unknown, but estimates range from 1,000 to 5,000. Worldwide, between 20 and 50 million people died. The pandemic led New Mexico to take steps to improve public health, such as the creation in 1919 of the State Board of Health and the Division of Public Health Nursing.

From 1921 to 1923, Charles Sternberg, a professional fossil collector then more than seventy years old, made astounding dinosaur discoveries in northwestern New Mexico. He worked initially on contract for the museum of Uppsala University in Sweden, but when that funding ran out, he sold fossils to the American Museum of Natural History and the Field Museum of Natural History. Sternberg’s field discoveries included two duckbill dinosaur skulls, one attached to a skeleton; two horned dinosaur skulls and a separate skeleton; and many turtles.

In 1923, the American Museum’s chief paleontologist, Henry Fairfield Osborn, described the skull Sternberg sent to New York as a new kind of horned dinosaur, naming it Pentaceratops sternbergi. As much as 27 feet long and weighing an estimated 6 tons, Pentaceratops was one of the largest (if not the largest) horned dinosaurs.

Following the discoveries of Reeside and Sternberg, Charles Whitney Gilmore, an accomplished curator at the Smithsonian’s United States National Museum in Washington, DC (which in 1911 became the Natural History Building), led an expedition to the northwestern New Mexico in 1929. Gilmore subsequently published a lengthy monograph comparing the New Mexican dinosaurs to those found in Montana and Alberta. He thereby first identified a dinosaur fauna that lived across much of western North America during the Cretaceous, about 75 million years ago.

The 1920s and 1930s saw notable achievements in dinosaur paleontology in New Mexico, but for the average New Mexican, they were challenging times. Prolonged drought meant sections of the state became part of the Dust Bowl. Persistent unemployment, high production costs, and shrinking markets led the state to the brink of economic disaster. It hit farmers and ranchers especially hard. There were numerous bankruptcies and foreclosures as land values reached the lowest value per acre in the U.S. One bright spot was the discovery of oil in northwestern and southeastern New Mexico. This built on an already long history that went back to the mid-1800s of exploitation of the state’s mineral wealth, especially in the form of gold, silver, and copper.

The Midwest Refining Company drilled New Mexico’s first commercial oil well on September 25, 1922, on the Navajo Reservation near Shiprock, although it was only moderately productive. Subsequent wells established the Hogback oilfield as a major producer in the San Juan Basin. The oil exploration activity coincided with the pioneering work of paleontologists Gilmore (1874–1945) and George Fryer Sternberg (1883–1969) in the Fruitland and Kirtland formations of northwestern New Mexico. The Midwest State No. 1 well struck oil near Hobbs on June 13, 1928, setting off a major boom. The success of these two regions made New Mexico one of the leading players in the oil and natural gas industry.

Edwin (“Ned”) Colbert (1905–2001), a curator at the American Museum of Natural History, was a world-famous authority on dinosaurs. In 1947, he led a team to relocate Baldwin’s Coelophysis site. In the red Triassic rocks at Ghost Ranch, preparator George Whitaker found a bonebed packed with many hundreds of dinosaur skeletons. This discovery made Coelophysis one of the best known of early dinosaurs. A bird-like, visual hunter about 6 feet long, Coelophysis ran down small game on the river floodplains that covered New Mexico during the Late Triassic, about 210 million years ago. At Ghost Ranch, something (perhaps a flood) killed hundreds of the small dinosaurs and buried them in one place.

New Mexico remained on the frontlines of many sciences, including paleontology, during and after the Second World War. Most famously, this included Los Alamos as the site of Project Y, the top-secret atomic weapons laboratory that J. Robert Oppenheimer directed. The work of the world-class scientists on the Pajarito Plateau culminated in the successful detonation of the Gadget, the first plutonium-based atomic explosive, on July 16, 1945, at the Trinity site near Alamogordo. On January 1, 1947, Los Alamos was transformed from a town under military control to a scientific community under the direction of the Atomic Energy Commission. Hastily constructed structures disappeared, and a modern town emerged, financed in large measure by the largess of the Federal Government.

After the Second World War, the military buildup of the Cold War brought many people to New Mexico to support and conduct scientific research at Los Alamos and Sandia National Laboratories, and to work at what became three major Air Force bases as well as the White Sands Missile Range. The postwar transformation of Albuquerque was astonishing. In 1940, the city had a population of 35,449. The 1950 census recorded 96,815 residents, with perhaps as many as 50,000 arriving after the war. Many newcomers represented a nationwide trend of people moving from rural areas to metropolitan centers. Albuquerque was also a magnet for people relocating to Sun Belt states, and gained population at a quicker pace than most other US cities.

Dinosaur paleontology is but one of many sciences that have an important connection to New Mexico. The state has also played an important role in the United States space program. In the 1930s, Robert Goddard pioneered rocketry near his home in Roswell. In 1945, Operation Paperclip brought German engineers and scientists to work at White Sands Proving Ground to work on a nascent rocket program. In 1961, Ham, a chimp trained at Holloman Aeromedical Lab, became the first primate launched into space. Geologist Harrison “Jack” Schmitt, a native of Santa Rita in Grant County, became the first civilian to walk on the moon in 1972. Ten years later, the space shuttle Columbia landed at White Sands Space Harbor.


The New Mexico State Legislature had designated Coelophysis as New Mexico’s official state fossil in 1980. The Legislature also created a state museum of natural history. For about a century, New Mexico had drawn dinosaur hunters from the nation’s largest natural history museums, but when the New Mexico Museum of Natural History opened in 1986 in Albuquerque, it provided an opportunity for people to see New Mexico dinosaurs in the land where they once roamed. Over the past thirty years, the museum has taken the lead in digging up, studying, and interpreting dinosaurs from around the state. One of the latest discoveries is of the armored dinosaur Ziapelta, known from a skull and neck armor and published by museum scientists and their collaborators in 2014. This new kind of armored dinosaur added to the growing list of dinosaurs known to only be from New Mexico.

The discovery of Ziapelta demonstrates the continued potential for new and exciting dinosaur discoveries in New Mexico, long after David Baldwin found those first fragments of dinosaur fossils in the 1880s. Indeed, the discoveries continue: More than a century of digging dinosaurs in New Mexico is just the beginning.

Dr. Spencer G. Lucas is curator of geology and paleontology at the New Mexico Museum of Natural History and Science. Dr. Rick Hendricks is New Mexico’s state historian.