This dataset measures colour and estimates body size of ant species collected across four vertical strata: subterranean, ground, understory and canopy in lowland tropical rainforest. Ants were collected using different trapping techniques in each stratum; baited traps were used in the subterranean, understory and canopy strata and Winkler extractions were used to collect ground ants. The colour of each ant species was classified categorically by eye using a set pre-determined colours. A single dominant colour was assigned for each species, this was determined as the modal colour across all body parts and individuals for each species. Each colour was linked to a set of RGB (red, green and blue) values which were extracted from the original colour wheel using the image editing software paint.NET (v.4.0.3); RGB values for each colour were converted into HSV (hue, saturation and value) format. Body size of each species was estimated by measuring Weber's length. Accompanying the ant species data set are four additional data files: 1) data set measuring intraspecific variation in colour, 2) data set measuring intraspecific variation in Weber's length, 3) data set measuring soil temperature, and 4) data set measuring UVB radiation at 5 m vertical intervals from the ground to the canopy. This data is a contribution from the UK NERC-funded Biodiversity And Land-use Impacts on Tropical Ecosystem Function (BALI) consortium. Full details about this dataset can be found at https://doi.org/10.5285/c0f65bf5-3cb0-41ab-be3d-982490cecba9