“This is a unique opportunity; we are studying nature’s blank pages,” said Ana Miller, a geomicrobiologist at the Institute of Natural Resources and Agrobiology of Seville in Spain who led the study published in Environmental Microbiome.

The tubes formed by the Tajogaite eruption were sometimes tall enough for a person to walk upright through them. But the temperatures could be uncomfortably hot, even after toxic gases had dissipated and initial temperatures cooled from upward of 800°C (1472°F). In some sampling sites, air temperatures hovered at a blow-dryer hot 60°C (140°F), while rock surfaces reached 90°C (194°F).

Yet even in such inhospitable conditions, the researchers found adventurous microorganisms already dwelling in the caves and, in some cases, altering the rock.

Field images of the main features and morphology of the newly formed lava tubes of the Tajogaite Volcano in La Palma and corresponding sampling points. A Sima Hornitos (TSH); B Canal Hornito Bonito Lava Tube (THB); C Tubo Rojo (TR), and D Shatter Ring-1 (TDS)

link to open access paper https://link.springer.com/article/10.1186/s40793-026-00874-y