The effect of environmental variability on species richness, community structure, and daytime activity of ants along a disturbance gradient was examined at El Cielo Biosphere Reserve, Tamaulipas, Mexico. The study site was delimited by LANDSAT satellite images. Ants were evaluated using pitfall traps from 0800 to 1800 every hour for four consecutive days in August 2016. In total, 1190 individuals of 20 species and seven subfamilies were obtained. Six species responded positively to the disturbed environment during the morning, with variation between assessment days. The daytime activity of ant species was variable during the day along the disturbance gradient. Solenopsis geminata was the species that showed the most activity during most of the day in the study. Abundance of species differed between most environments each hour. The total variation explained by the first two axes of the relationship analysis of species abundance and environmental attributes was 83% (Axis 1: Temperature and humidity = 64%, Axis 2: Rocks = 19%). S. geminata and Forelius pruinosus were the species that responded significantly to the variables evaluated. The results suggested that environmental variability along a disturbance gradient determines the establishment of the niche and the diurnal activity profile of each species throughout the day and between days.