This variability results from developmental mechanisms that coincide with genetic predisposition in relation to nutrition, stress, exposure to parasites, and/or physiological conditions.

[7] Dynastes hercules is highly sexually dimorphic, with only males exhibiting the characteristic horns (one on the head, and a much larger one on the prothorax).

Females have an average gestation period of 30 days from copulation to egg-laying, and may lay up to 100 eggs on the ground or on dead wood.

[5] The larvae of the Hercules beetle are saproxylophagous, meaning that they feed on rotting wood; they reside in same during their two-year developmental stage.

[10][14][15] Within their native rain forest habitats, the adult beetles, which are nocturnal, forage for fruit at night and hide or burrow within the leaf litter during the day.

[11] The adult D. hercules beetles are capable of creating a 'huffing' sound, generated by stridulating their abdomen against their elytra to serve as a warning to predators.

Experiments on D. hercules have shown that a male placed in the vicinity of a female will immediately orient towards her and seek her out, suggesting chemical communication through strong sexual pheromones.

[16] It has been observed in wild habitat and in captivity that male D. hercules will engage in combat to win possession and mating rights to a female.

Actual measurements on a much smaller (and relatively stronger: see square-cube law) species of rhinoceros beetle show a carrying capacity only up to 100 times their body mass, at which point they can barely move.

[20] Dynastes hercules is a beneficial contributor to the rain forest ecosystem, primarily during their larval stage where they are saproxylophagous.