Wild island horses may have legendary origins

The feral horses on Virginia's Assateague Island are visited by thousands of nature enthusiasts, photographers, and people who just love horses

Assateague's wild horses are well known, even to many people who have never been to the island. 

Did the Mediterranean break through the Dardanelles to form the Black Sea when water levels rose long ago? Was a lingering folk memory of such a catastrophe behind the Noah’s flood story? Could the Thera volcanic eruption, of around 1,500BC, have caused Pharaoh’s ten plagues?

Are most fables, even modest ones, rooted in fact?

A paper, just published, lends support to that idea; it examines a myth surrounding the semi-wild horses which roam Assateague Island off the coast of Virginia.

The horse evolved in North America 40 to 50 million years ago but became extinct there around Ice Age times. Fortunately, horses had colonised Eurasia 2.5 million years previously. Otherwise, none would be available on Grand National day!

The Spanish conquistadors had little that is positive to recommend them, but the plundering invaders did reintroduce horses to the continent of their equine ancestors. Columbus brought some on his second visit in 1419 and Cortes’ expedition of 1519 included 16 of them. Just like the turkeys eaten at Thanksgiving in the US, the horses in America today are of European descent.

How ponies came to be on Assateague Island has been much debated. There are two candidate explanations. The simpler one is that their ancestors were moved there from mainland Virginia to hide them from the authorities and evade the taxes levied on horse-owners.

Misty of Chincoteague by Marguerite Henry

The other possibility is a romantic one, popularised by children’s author Marguerite Henry. On a visit to the island in 1947, she wrote Misty of Chincoteague, an award-winning novel about a feral horse and her foal. The book was inspired by a local tradition that, centuries ago, the ancestors of the Assateague ponies had swum ashore from a Spanish galleon wrecked in a storm. Historians dismiss the suggestion for lack of evidence, but research just published may force them to reconsider their verdict.

Nicolas Delsol, of the Florida Museum of Natural History, is an anthropologist researching American colonial history. He is currently examining the origins of domestic cattle. This involves mitochondrial DNA analysis of teeth unearthed by archaeologists.

One tooth, which he had assumed was a cow’s, turned out not to belong to a horse. The settlers didn’t eat horse-flesh, so archaeologists discover far fewer remains of horses than of cattle. Finding a horse tooth was not that significant, but tests showed that this one was special; its mitochondrial genome is the oldest yet sequenced of any domestic horse in the New World. The animal had lived around 500 years ago.

The tooth was found at the site of an early Spanish settlement on the Caribbean island of Hispaniola, now known as Haiti, some 1,400km south of Assateague.

Assateague's wild horses are split into two main herds, one on the Virginia side and one on the Maryland side of Assateague. They are separated by a fence at the Virginia/Maryland State line. These herds have divided themselves into bands of two to 12 animals and each band occupies a home range. The National Park Service manages the Maryland herd. The Chincoteague Volunteer Fire Company owns and manages the Virginia herd, which is allowed to graze on Chincoteague National Wildlife Refuge, through a special use permit issued by the U.S. Fish and Wildlife Service. The permit restricts the size of the herd to approximately 150 adult animals in order to protect the other natural resources of the wildlife refuge. It is the Virginia herd which is often referred to as the 'Chincoteague' ponies. Picture: US National Parks Services

To track down the nearest living relatives of the horse, whose tooth he had analysed, Delsol examined the mtDNA profiles of American and European breeds. The horse proved to be of Spanish origin and its nearest relatives, he found, are on Assateague. This suggests that the island’s famous ponies have been there for centuries.

Perhaps the legend that Misty and her foal were shipwreck survivors isn’t entirely fictional!

• Nicolas Delsol et al. Analysis of the earliest mtDNA genome of a Caribbean colonial horse from 16th Century Haiti. PLOS 1. 2022