Solounias and colleagues believe the horse's first and fifth toes evolved into what we now know as the wings—the palmar and plantar processes—of the coffin bone, within the hoof. | Photo: iStock

Horses evolved from five toes, to four toes, to three toes, and eventually to a single toe that’s embedded inside the hoof. Right?

Not necessarily. Researchers at New York Institute of Technology College of Osteopathic Medicine (NYITCOM) recently published a study in which they suggest horses still have all five digits, they’re just in various forms of development. And this theory of digit “reduction,” they say, is more in line with evolution in general.

“Evolution is creative without loss of structures, so that structures (like toes) are usually modified but not entirely lost,” said Nikos Solounias, PhD, paleontologist and anatomy professor at NYITCOM, in Old Westbury, New York. “That’s the more common pattern. Complete loss is rather atypical in evolution