Meriwether Lewis and William Clark are known as trailblazing explorers of the American West, not pioneering scientists. But during their 8,000-mile journey from Missouri to the Pacific Ocean and back between 1804-1806, Lewis and Clark discovered 122 animal species, including iconic American animals like the grizzly bear, coyote, prairie dog and bighorn sheep.

When President Thomas Jefferson first charged his assistant Lewis with the mission of finding a passable river route to the Pacific, he included an assignment to 鈥淸observe] the animals of the country generally, & especially those not known in the U.S. the remains and accounts of any which may [be] deemed rare or extinct.鈥

Jefferson was especially enticed by fossils recovered of mastodons and a type of giant land sloth he dubbed the megalonyx (鈥渂ig claw鈥). Unsure of what species the men would encounter in the wilds beyond Missouri, Lewis took crash courses in botany, zoology and specimen collection and preservation from the best scientific minds in Philadelphia.

Clark Describes a 'Village of Small Animals'

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Lewis and Clark came upon prairie dogs in 1804 and described them as "little animals" that "make a whistling noise."

One of the most remarkable periods of the expedition (zoologically speaking) occurred between September 4 and September 24, 1804 during a 263-mile trek from the Niobrara River in Nebraska to the Teton River in modern-day Pierre, South Dakota. In a span of just over two weeks, Lewis and Clark encountered four classic Western animals for the first time: the prairie dog, pronghorn, coyote and the jack rabbit.

In his September 7, 1804 journal entry, Clark describes a 鈥淰illage of Small animals鈥 discovered in Boyd County, Nebraska. The men found a sloping hillside containing 鈥済reat numbers of holes on top of which these little animals Set erect make a Whistling noise and whin alarmed Step into their hole.鈥

Anxious to capture a live specimen, the men tried digging down into the burrows, but after reaching a depth of six feet, they switched tactics and attempted to flush the critters out.

鈥淭hey spent an entire day hauling buckets of water up from the Missouri River and dumping them down the holes,鈥 says Jay Buckley, a history professor at Brigham Young University and author of several books on Lewis and Clark, and Western exploration. 鈥淓ventually they flushed one out, put it in a cage and sent it to Jefferson. Incredibly, it made the trip alive.

There was some disagreement over what to name the curious creatures. Lewis called them 鈥渂arking squirrels鈥 while Clark referred to them as 鈥済round rats鈥 or 鈥渂urrowing squirrels.鈥 It was Sergeant John Ordway, an Army volunteer, who first called them prairie dogs.

Lewis Marvels at a 'Jackass Rabbit'

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A Blacktail jackrabbit. Lewis noted the rabbit with remarkable ears could leap 18 to 20 feet in a single bound.

On September 14, 1804, near Chamberlain, South Dakota, one of the men killed a large white hare whose long, donkey-like ears inspired the name 鈥渏ackass rabbit,鈥 later shortened to jack rabbit. In his journal, Lewis marveled at the jack rabbit鈥檚 flexible ears, which the animal could 鈥渄ilate and throw鈥 forward, or contract and fold... back at pleasure.鈥 He observed the jack rabbit could leap 18 to 20 feet in a single bound.

On the very same day near the mouth of Ball Creek in South Dakota, Clark shot a 鈥淏uck Goat鈥 of an intriguing species of deer. In his journal, Lewis described the striking animal as having forked horns or 鈥減rongs鈥 and its 鈥渂rains of the back of his head.鈥 Consulting his eight-volume A New and Complete Dictionary of Arts and Sciences, published in 1764 by W. Owen, Lewis concluded that 鈥渉e is more like the Antilope or Gazelle of Africa than any other Species of Goat.鈥

In fact, the pronghorn is neither goat, antelope or deer, and belongs to its own family, Antilocapridae. The pronghorn is also the fastest four-legged species in North America, reaching top sprinting speeds of 60 mph. Lewis and Clark stuffed two pronghorn, one male and one female, and shipped them back East to Jefferson.

The mournful wails and yelps of coyotes followed Lewis and Clark to the Pacific and back, but the team shot and identified the first of this new species on September 18, 1804 near Chamberlain, South Dakota, and Clark called it a 鈥淧rairie Wolff.鈥

鈥淚 killed a Prairie Wolff, about the size of a gray fox, bushy tail head and ears like a Wolf, Some fur burrows in the ground and barks like a Small Dog,鈥 wrote Clark.

Grizzlies, Rattlesnakes, Bison Nearly Killed the Explorers

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An illustration from Lewis and Clark's journal of the Corps of Discovery, 'American having struck a Bear but not killed him escapes into a tree.'

Not all of Lewis and Clark鈥檚 animal encounters were so calm and collected.

鈥淥ne of my favorite moments is when Lewis is all alone at the Great Falls in Montana,鈥 says Buckley. 鈥淚n a 24-hour period, he鈥檚 nearly bitten by a rattlesnake, attacked by a wolverine, charged by a bison and eaten by a grizzly bear. That night, in his journal he says, 鈥楾he entire animal kingdom has conspired against me!鈥欌

As for grizzlies, Lewis and Clark were skeptical at first of the native Mandan and Hidatsa鈥檚 accounts of 鈥渨hite bears鈥 weighing over 1,000 pounds, and the explorers scoffed at the war paint and other 鈥渟upersticious rights鈥 the Indians performed before setting out to hunt the mythical beasts.

But later, while traversing Montana, Lewis and Clark became believers. In his trademark creative spelling, Lewis described 鈥渁 most tremendious looking anamal, and extreemly hard to kill notwithstanding he had five balls through his lungs and five others in various parts鈥 and made the most tremendous roaring from the moment he was shot.鈥

When Lewis had his close call with a grizzly in Great Falls, he described a massive bear chasing him 鈥渙pen mouthed and full speed鈥 into the river. With nowhere to run, Lewis spun around to face the grizzly armed only with his spear-headed 鈥渆spontoon.鈥 To his great relief, the animal retreated.

鈥淪o it was, and I feelt myself not a little gratifyed that he had declined the combat,鈥 wrote Lewis.

Despite the great care taken by Lewis and Clark to collect specimens and include detailed descriptions and measurements of plants and animals in their journals, the men never achieved scientific fame in their lifetimes. After their triumphant return in 1806, Lewis planned to write a three-volume account of their expedition with an entire volume dedicated 鈥渆xclusively to scientific research, and principally to the natural history of those hitherto unknown regions.鈥

But Lewis, overburdened in his new post as governor of Louisiana, died suddenly in 1809, and when the expedition journals were finally published in 1814, the editors left out almost all of the zoological and scientific reports. It wasn鈥檛 until 1893 that a new edition of the journals was published by naturalist Elliott Coues, who correctly credited Lewis and Clark as scientific trailblazers as well as daring American explorers.

黄瓜视频直播 Vault: Lewis and Clark: Explore New Frontier

Discover the adventures of Meriwether Lewis and William Clark as they traversed the vast, unknown continent of North America.