THURSDAY, Nov. 10 (HealthDay News) -- All the color variations seen in prehistoric cave paintings of horses actually existed in pre-domestic horse populations, which indicates that the ancient human artists accurately depicted their natural environment, according to a new study.

The research is also the first to provide DNA evidence of spotted horses in the Paleolithic period. Previous DNA studies produced evidence only for bay (reddish brown) and black horses.

In the study, an international team of researchers conducted DNA analyses of the bones and teeth of 31 pre-domestic horses found in 15 locations including Siberia and Europe. Some dated as far back as 35,000 years.

The results showed that 18 horses were bay, seven were black, and four had distinctive "leopard" spotting.

Cave paintings showing horses with leopard spotting have been controversial, such as a cave painting in France that's more than 25,000 years old and shows a white horse with dark spots.

Some experts believed it was unlikely that ancient horses had the genetic programming for a spotted coat and some have suggested the cave painting depictions of spotted horses were symbolic or abstract.

But this study shows that the cave paintings were realistic.

The study appears in the Nov. 7 online issue of Proceedings of the National Academy of Sciences.

"Our findings lend support to hypotheses that argue that cave paintings constitute reflections of the natural environment of humans at the time and may contain less of a symbolic or transcendental connotation than often assumed," Michi Hofreiter, of the department of biology at the University of York in England, said in a university news release.

More information

The American Museum of Natural History has more about the evolution of horses.