Neanderthals’ cultural practices, similar to those of Indigenous peoples, might be the answer to the mystery of their high δ¹⁵N values. Ancient hominins were butchering, storing, preserving, cooking, and cultivating a variety of items. All these practices enriched their paleo menu with foods in forms that nonhominin carnivores do not consume. Research shows that δ¹⁵N values are higher for cooked foods, putrid muscle tissue from terrestrial and aquatic species, and, with our study, for fly larvae feeding on decaying tissue.

I mean, this makes sense. Other primates eats grubs. But I would never have come up with this theory without someone else suggesting it first.