The Pleistocene Trackways of White Sands National Monument
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National Park Service White Sands U.S. Department of the Interior First Discoveries What We Are Learning Now Pleistocene Epoch Happenings White Sands National Monument In 1932, Ellis Wright, a government trapper, In 2001, tracksites in the monument were re- A lot was going on during the late Pleistocene. found large tracks on the west side of the examined. Twenty-five mammoth tracks and It was during this period that our earliest White Sands. He thought that he had 64 camel footprints from the late Pleistocene human ancestors appeared and gradually The Pleistocene discovered the tracks of a giant human! Each epoch were discovered. Additional trackways evolved into Homo sapiens. By this time, the track was approximately 22 x 10 inches, the were also discovered on the southern shore of continents had moved into their modern Trackways of White size of a rectangular place mat. Subsequent Lake Lucero. There were hundreds of them, all positions and one of the last major Ice Ages investigators thought that the tracks were of which were nearly east-west in orientation. shaped the land through dozens of interglacial Sands National indeed human because the print was perfect Unfortunately, the tracks were poorly preserved and glacial periods. In North America, glaciers and even the instep was clearly marked. in the soft gypsum. Their age was determined to advanced and retreated, sometimes extending Monument be about 30,000 years old by carbon dating the all the way down into New Mexico. Large It was not until 1981 that further investigation seeds and other plant matter embedded in the mammals (megafauna) were plentiful and the of the tracks identified them as mammoth, track itself. These tracks pre-date the arrival of climate dramatically shifted, changing from giant camel, and an undetermined humans in the area by about 20,000 years. cool and moist to hot and arid. mammal. During a tour by the New Mexico Archaeological Council in June of 1984, a Since 2007, researchers and monument staff large mammoth molar fragment was observed have discovered even more fossilized tracks in a small gully within 800 feet of one of the within the monument. They may represent the Present mammoth tracksites. Unfortunately, there is no largest concentration of Pleistocene trackways record that the fossil was ever recovered. in the United States. They appear to be primarily ave you ever wondered what the Tularosa from mammoths, camels, dire wolves, and HBasin, home to White Sands, looked like What Does the Future Hold? saber-toothed tigers. While most of them 30,000 years ago? Was it a desert like today— pre-date humans in the area, a few recently Epoch or was it perhaps lush with lots of plants and Tracks found in the monument are preserved discovered sets of fossil tracks appear to be Holocene 6ft Man animals? in gypsum layers and are quite fragile. Once associated with archaeological artifacts. This exposed from beneath the sand, the tracks suggests the possible co-existence of humans d This present-day desert was once a verdant land weather rapidly. Many of the recently found and mammoths in the basin. The majority of 10,000 ya o Saber-toothed Tiger teeming with prehistoric plants and animals. i tracks have already eroded and disappeared. the fossil tracks suggest that the ancient animals r The climate during the Pleistocene epoch was traveled to and along the shorelines of Lake e Because they breakdown so quickly, P much wetter and cooler than today. Rain and monument staff is working with experts Otero and across the surrounding wetlands y snowmelt filled a 1,600 square-mile lake called r to develop a strategy for conservation and during the late Pleistocene. a Lake Otero. Clues of this past oasis are found monitoring of the tracks. Their scientific n in the ephemeral trackways left behind by the r significance underscores the need for e Ancient Camel Dire Wolf t Pleistocene giants that once called the Tularosa Epoch continuing research into these incredible a u Basin home. Scientists are studying these and rapidly vanishing natural wonders. Pleistocene trackways to gain a better understanding of this Q ancient ecosystem and the mighty mammals that 2009 2010 2011 ruled the day. Scan for an in-depth explanation of the 1.7 mya geologic story of White Sands and the Columbian Mammoth Tularosa Basin. Weathering of exposed mammoth tracks Images are to scale Saber-Toothed Cat Dire Wolf Smilodon fatalis Canis dirus Known for its large canines, one species of Looking very much the modern-day gray saber-toothed tiger, Smilodon fatalis, stalked wolf, the dire wolf hunted the grasslands the Tularosa Basin until about 10,000 years of the basin until around 10,000 years ago. Unlike its colloquial name suggests, it ago. Similarities between the two species, was not related to any modern feline species. however, stop at appearances. It was, however, larger and had a more robust build than modern “big cats” such The dire wolf was much heavier and had as tigers, lions, leopards, and cougars. powerful bone-crushing jaws and teeth. Its c. Sergiodlarosa c. Sergiodlarosa legs were shorter and its shoulder blades Columbian Mammoth 6ft Man Ancient Camel As frightening as its canine teeth may look, more massive than the modern gray wolf. the smilodon’s bite was relatively weak. The Weighing between 125 and 175 pounds, it larger teeth reduced the space available for was about the size of an English Mastiff—one jaw muscles, reducing bite pressure. Biting of the biggest and heaviest dogs recognized down too hard on a prey animal could result by the American Kennel Association. in the breakage of one of its canines. Mammoths Camels The dire wolf’s rear teeth were adapted Mammuthus primigenius Camelops hesternus The smilodon’s bobed-tail suggests that for tearing, not chewing. This suggests that Mammuthus columbi The ancient western camel evolved rapidly did not chase down prey like lions or tigers it did not chew its meal but tore off large whose long tails help them maintain balance Mammoth species in North America between 33mya and 12mya, finally developing chunks of flesh and swallowed them whole. while running. Instead, they were more included the Wooly mammoth (Mammuthus into Camelops hesternus. Originating in They were not picky eaters so any animal likely opportunistic hunters, hiding in tall Primigenius) and Columbian mammoth North America, camelops probably looked available was on the menu. Larger animals grasses and ambushing prey animals. Its (Mammuthus columbi). Tracks from both like a large dromedary, a modern-day one- like bison could also be taken down by diet would have included prehistoric deer, species have been found in White Sands but the hump camel. It went extinct around 11,000 hunting in packs of 30 wolves or more. bison, and an occasional mammoth. majority are from the Columbian mammoth. years ago, probably due to pressures such as increased hunting and global climate change. Both mammoths were herbivores, eating mostly grass but grazing on other types Weighing-in at around 1,764 pounds, camelops of plants as well. Like today’s elephants, would have dwarfed its modern cousin, which they ate 600 pounds of food and drank weighs around 1,433 pounds. Its limbs were 40 gallons of water daily. In fact, they also longer and its estimated shoulder height spent 16–18 hours a day either feeding or was seven feet. Like modern camels, it was an moving toward a source of food or water. opportunistic herbivore that would eat any vegetation it could reach. Although modern Like modern elephants, mammoths used camels are known for being able to survive their tusks to dig and collect food and to for long periods without water, it is unknown intimidate and fight-off predators and rivals. whether camelops was able to do the same. c. Sergiodlarosa Their tusks began to form at birth and grew c. Sergiodlarosa Dire Wolf throughout their lifetime, gaining a new Saber-toothed Tiger 6ft Man layer each year. Like tree rings, changes in tusk growth rate generally reflect changes in the animal’s nutritional condition. Images are to scale Revised 04/05/2016.