Researchers say the cave drawings, dated to around 44,000 years, may represent the capacity for religious or spiritual thinking.
Study looks at the reasons behind "an enigmatic feature of the rock art" found at sites across Western Europe.
For as much as it might reveal about ancient island cultures, the art itself is incredibly tiny.
"The thing that surprised us the most was the sheer size of some of the engravings."
The engraving, known as a petroglyph, shows a circle with curved, intricate swirling emissions issuing from it.