Neanderthals from Cartagena Already Planned Their Menu One Hundred Fifteen Thousand Years Ago

Published on May 24, 2026 | Translated from Spanish

A study from the University of Burgos reveals that the Neanderthals of Cueva de los Aviones in Cartagena did not eat shellfish randomly. Through the analysis of oxygen isotopes in shells of the small periwinkle and the ferruginous limpet, scientists determined that gathering was concentrated between November and April, almost completely avoiding the summer months. This behavior demonstrates seasonal planning.

Neanderthal figure crouched at a rocky shoreline during winter, carefully prying a limpet shell from a wet stone with a sharp flake tool, woven basket already half-full of assorted shells, stormy grey sky and rough sea in background, demonstrating seasonal foraging behaviour, realistic paleoanthropological reconstruction, detailed texture on shell edges and tool surface, natural overcast lighting, cold blue-grey tones, photorealistic scientific illustration

Oxygen Isotopes: The Chemical Fingerprint of Seasonality 🧬

The technique used by the research team is based on measuring variations in stable oxygen isotopes (δ18O) in mollusk shells. These variations correlate with water temperature at the time of shell growth, allowing the collection season to be inferred with precision. By analyzing a broad sample of shells from the site, a clear pattern was observed: the majority corresponded to cold months, while those collected in summer were a minority. This rules out opportunistic gathering and points to intentional selection.

Gourmet Neanderthals: Oysters in Winter, Fasting in August 🦪

Apparently, Neanderthals already knew that shellfish in summer isn't as cool. Or maybe it was to sweat less in the heat. The point is that these Cartagena hominids had more foresight than many of us planning dinner. While they organized themselves to avoid hunger in winter, we debate whether to order pizza or sushi on a Friday. Sure, they didn't have a fridge, but they had a brain.