Listen to part of a lecture in an archeology class.

Listen to part of a lecture in an ecology class.

Okay, let's get started. Earlier, we were talking about prehistoric paintings found on the walls of caves in Europe, paintings dating back more than 25,000 years of large wild animals, animals like deer, lions, horses. Let's get back to the horses now. There are cave paintings of black horses and brown horses. But in a few caves in southwestern France, there are also paintings of a third kind of horse, of spotted horses -- white horses covered with black spots.Now for quite a long time, researchers have been asking “did these paintings depict animals as they actually existed, or are they imaginary representations, perhaps with symbolic meanings?” You see, spotted horses do exist among modern horses today, and we know they've existed for the last 5000 years, since horses were first domesticated.In fact, among modern horses, there's a huge variability in coat color, black and brown, yes, but also red, white, grey, spotted. And it's commonly believed that this variation came about through domestication. But as to whether spotted patterns existed in the coats of pre-domesticated horses at the time the cave paintings were made, well, for a long time, we didn't know.I mean, for a while now, we'd known the genetic code in DNA that causes horses to be black or brown, but for a long time, we didn't know the genetic variant for spotted coats. So in an earlier study, when scientists analyzed the DNA from bone samples from 31 pre-domesticated horses, horses dating back as far as the cave paintings, they found genetic evidence for black and brown horses, not spotted horses.But recently, the genetic code for spotted horses was discovered, and so the scientists went back to those same bone samples and did a new study. And you know what they found? Six of these 31 ancient horses had the genetic sequence associated with the spotted coat pattern, so this is pretty good proof that spotted horses really did exist when the paintings were created.Okay, but why is it so important to know that these paintings are of real animals or not?Well, think about it, some of the animal species in these paintings are now extinct, right? For example, we've never actually seen a live woolly mammoth with its long, shaggy coat and enormous curved tusks, or a woolly rhinoceros. But now that we know that the spotted coat pattern of the horses in the paintings existed at the time they were painted, well, that gives us more confidence that these prehistoric humans were drawing what they were actually seeing. It makes us all the more sure that, well, yes, that's very likely what a woolly mammoth looked like. So that's one answer to your question. Another reason why this genetic finding is important is that it proves that the spotted coat pattern predates the domestication of horses and by quite a long time.But interestingly, the study also shows that spotted horses weren't as common as the black and brown horses, and researchers are speculating why. Some modern, domesticated spotted horses don't see well in the dark. If prehistoric spotted horses also had trouble seeing at night, which seems likely, they would have been more vulnerable to predators, which would explain why they were less common. Yes, Kathy?They would have been more vulnerable to predators anyway. I mean, a white spotted coat would have stood out more than a brown or black coat.That's true. But on the other hand, the white coat with black spots might have provided better camouflage during the Ice Age, when there was snow and ice everywhere, at least until the Ice Age ended, when, as you say, they would have stood out more. Well, anyway, we now know that these cave paintings do not depict fantasy animals, but real horses observed from life.But they still could have had symbolic meanings, couldn't they? Even if they were basically realistic?Certainly, and as a matter of fact, in some of these paintings, there are dots on the horses themselves showing the coat pattern, but there are also dots surrounding the horses all around them. So who knows? Maybe the paintings do also contain some symbolic expression.