Scientist Measuring Lichen on Granite in Querétaro

Bright tropical afternoon light strikes a rough granite boulder in Santiago de Querétaro, illuminating patches of pale green and gray lichen clinging to the stone. A researcher stands at eye level, holding a white ruler card with black markings against the rock face to measure the growth. The late afternoon sun casts sharp shadows that define the texture of the mineral surface. Nearby, a piece of scientific equipment features a metal housing where small red and green indicator lights reflect off the polished casing. Early spring air leaves the surrounding vegetation dry and dormant, showing the stark contrast between the organic lichen and the hard stone. The ruler aligns perfectly with the irregular edges of the biological patches, marking the methodical scale of the study.