The Weight of the World on Its Horns 

What am I looking at?

This is an Atlas beetle (Chalcosoma atlas). You can see its three large horns – the cephalic horn on its head and two more on its thorax (1); its mouth (2); and its short antennae (3).

Biology in the background

These beetles live in Southeast Asia and are known for their strength and size. The males are larger than the females and have three very large, exaggerated horns that they use to fight each other over mating rights. They try to hook one or more of their horns underneath a rival male and flip them over (or off a branch if that’s where the battle is taking place). But although they’re strong, these beetles are not the most agile of insects; if they’re flipped onto their back, they remain helpless for a short time until they can right themselves.

This example of the species isn’t particularly well-endowed; the horns of some males can be at least double the length seen here. The size of a given insect’s horns, relative to the length of its body, isn’t dictated solely by its genes but also depends on its diet in the larval stage. The more nutrient-rich food it consumes as a grub, the larger its adult horns.

These insects can grow up to 12 centimeters long, or a little larger than the length of a human palm.

Technique

These images were created using macrophotography.