We may look at Neanderthals as sort of the dumb cousin to Homo sapiens who couldn’t hack it when the going got tough, becoming extinct as we went on to thrive. But a new study finds that they may have actually been significantly smarter than early humans, and bad timing may have been the only reason they’re not still around and we are.

The study, published in Nature Communications, describes the ancient hominins that lived in Europe and Asia about 300,000 years ago, noting that they were able to create tools and jewelry, and even performed some primitive dentistry. But when Homo sapiens arrived on the scene, Neanderthals vanished.

Scientists assumed that Neanderthals just had something wrong with them, and maybe a disease wiped them out that Homo sapiens could handle. But the study indicates that it may have been something as mundane as population dynamics and bad timing that tipped the scales in our favor and against theirs.

“Most hypotheses in the heated debate about the Neanderthals’ replacement by modern humans highlight the role of environmental pressures or attribute the Neanderthals’ demise to competition with modern humans, who occupied the same ecological niche,” reads the abstract from the paper. “The latter assume that modern humans benefited from some selective advantage over Neanderthals, which led to the their extinction. Here we show that a scenario of migration and selectively neutral species drift predicts the Neanderthals’ replacement.”