Other researchers dispute it:
One partial skeleton known as the “flower burial” was surrounded by clumps of pollen that led Solecki to conclude that Neanderthals had scattered flowers over the body as part of an ancient burial practice. But critics had argued that the individuals in the cave may have died from exposure or falling rocks, after which their bodies were naturally covered with dirt and plants…
Archaeologist Dennis Sandgathe of Simon Fraser University in Canada questions Pomeroy’s conclusion. “As with all previous claims for Neandertal intentional burials, there are no smoking guns clearly indicating intentional burial [of Shanidar Z],” he tells Science News, noting that the “rather loose fetal position” of the body suggests it may have been randomly deposited.Amy Schleunes, “Neanderthal Skeleton Find Supports Idea of Intentional Burials” at The Scientist
Actually, burying the deceased in a fetal position might be evidence of a belief in rebirth. It’s the same general idea as burying the deceased with tools.
See also: Neanderthal Man: The long-lost relative turns up again, this time with documents
A deep and abiding need for Neanderthals to be stupid. Why?