Insect remains reveal Indigenous burial practices in the Canary Islands

In a shadowy cave on the island of Gran Canaria, Spanish archaeologists have coaxed a forgotten story out of 8,000 tiny insect remains — and it rewrites what we thought we knew about how the island's Indigenous people treated their dead.

The cave, called Cruz de la Esquina, dates to the 7th to 9th centuries AD. Before the Spanish conquest in the 15th century, the Canary Islands were home to Indigenous communities whose culture and customs — especially their burial practices — are still poorly understood, largely because much was destroyed during colonization.

Researchers already knew these communities placed wrapped bodies inside caves for burial. But two things remained unclear: how quickly after death the burials happened, and whether the caves had served some other purpose first. The Cruz de la Esquina cave offered a rare chance to find out, because its "extraordinary preservation" had kept organic materials like wood, rope and leather intact — including the remains of insects that had lived there centuries ago.

Lead author Pedro Henríquez-Valido of the University of Alcalá and his team, writing in the journal Antiquity, identified more than 8,000 preserved arthropod remains spanning many species. The mix of species told a surprising story. A significant share were storage pests — the kind of insects that infest stored grain. The sheer quantity of these pests suggested far more cereal was present than would make sense if grains had simply been placed with bodies as funerary offerings.

"This research indicates that corpses were instead buried shortly after death."

The team's conclusion is striking: before Cruz de la Esquina became a burial place, it was a granary. Indigenous people stored large amounts of grain there, and only later adapted the space for funerals. The insects were, in effect, silent witnesses to the cave's changing purpose.

The findings also overturn an older idea. Some earlier interpretations suggested bodies may have been left in the sunlight to decompose before being laid in the caves. The insect evidence points the other way — people were buried soon after they died.

The discovery matters far beyond one cave. "Archaeoentomological remains have revealed the hidden biography of Cruz de la Esquina," says Henríquez-Valido. By studying the bugs that shared these spaces, researchers say they can add a new layer to knowledge of cultural practices that remain poorly understood — and even help identify similar sites across the wider island.

The team now plans to apply the same insect-based methods to other caves across Gran Canaria. Their goal: to find out whether Cruz de la Esquina is part of a broader pattern across the Canary Islands or an isolated case. Co-author Jean-Bernard Huchet of the University of Bordeaux sums up the potential simply: this approach offers "new perspectives on the transformation of archaeological deposits." Sometimes the smallest remains hold the biggest clues about how people lived — and how they honored the ones they lost.