Camels, often pictured traversing vast deserts in Africa and Asia, have a surprising evolutionary past. While many associate them with the Middle East or North Africa, the camel family originated and spent tens of millions of years evolving on a different continent entirely. The true story of camels begins in North America, their evolutionary birthplace before they embarked on global journeys.
North America: The Cradle of Camels
The evolutionary journey of camels began in North America approximately 44 to 45 million years ago during the middle Eocene epoch. Early camel ancestors, like Protylopus, were small, roughly the size of a rabbit, and lived in what were then rainforests, a stark contrast to the modern camel’s desert habitat. These early forms possessed four-toed feet, suggesting hooves rather than the padded feet seen in today’s camels.
Over vast stretches of geological time, camelids diversified across the North American continent. By 20 million years ago, around 13 different genera of camels thrived there. Later, larger species such as Camelops, also known as the Western Camel, emerged during the Pliocene epoch, around 4 to 3.2 million years ago. Camelops was a sizable animal, reaching a shoulder height of about 7 feet (2.3 meters) and weighing up to 1,800 pounds (816 kg), resembling modern dromedary camels. Fossil evidence of Camelops has been discovered across western North America, from Alaska to Honduras, indicating its widespread presence.
The Great Migration and Diversification
From their North American homeland, camelids undertook migrations to other parts of the world. One major migratory wave occurred across the Bering Land Bridge, a landmass that periodically connected Asia and North America during periods of lower sea levels. Ancestors of Old World camels, such as Paracamelus, crossed this land bridge into Eurasia around 7 to 6 million years ago. This lineage eventually diversified into the one-humped dromedary camels and the two-humped Bactrian camels found in Africa and Asia today.
A separate migration saw camelids move south into South America approximately 3 million years ago, a journey facilitated by the formation of the Isthmus of Panama. These southward-migrating camelids evolved into the New World camelids, which include llamas, alpacas, guanacos, and vicuñas. These species adapted to the diverse environments of South America, from the high Andes to mountainous and desert ranges.
Why North America’s Camels Vanished
Despite originating and flourishing in North America for millions of years, native camel species disappeared from the continent around 10,000 to 13,000 years ago. This extinction was part of a larger event known as the end-Pleistocene extinction, which saw the disappearance of many large mammals across the Americas. Camelops was the last surviving native camel genus in North America before this event.
The precise reasons for this widespread extinction are still under investigation, but theories point to a combination of factors. Climate change at the end of the last ice age, leading to environmental shifts and reduced food availability, contributed. The arrival of humans in North America around the same period also played a role, with evidence suggesting early humans hunted Camelops. A combination of these environmental pressures and human impact likely led to the demise of North America’s native camel populations.
Camels Today: A Global Presence
Today, camelids are found across various parts of the world, a testament to their migratory history. Old World camels, including the one-humped dromedary and two-humped Bactrian camel, are widespread in the arid and semi-arid regions of Africa, the Middle East, and Asia. Dromedaries account for about 94% of the world’s camel population and are particularly concentrated in countries like Chad, Somalia, Sudan, and Kenya, where they are valued for milk, meat, and transportation. Bactrian camels, better adapted to colder climates, are found across Central Asia.
In South America, llamas, alpacas, guanacos, and vicuñas thrive, having diversified considerably since their ancestors migrated from North America. Llamas and alpacas are domesticated and are utilized for their wool, meat, and as pack animals, while vicuñas and guanacos remain wild. Although native camels vanished from North America, small, non-native populations of Old World camels exist there today, primarily as feral descendants of animals imported in the 19th century for various uses, such as the U.S. Army’s experiments with camels.