Praying Mantis

The praying mantis is one of the most efficient ambush predators in the insect world — a patient, camouflaged hunter with 3D vision, a swivelling head, and a pair of folding, spiked forelegs that close faster than you can see.

Overview

There are around 2,400 mantis species, found on every continent except Antarctica and most diverse in the tropics. They live wherever there are insects to catch — grassland, scrub, forest, gardens — and they are sit-and-wait predators, choosing a spot on a flower, a stem, or a branch and staying motionless until something edible comes within reach.

Built to ambush

• Camouflage. Mantises are masters of disguise. Different species mimic green leaves, dead leaves, bark, sticks, grass blades, lichen, and — most spectacularly — flowers, with petal-shaped legs that lure pollinating insects straight into range.
• Vision. Two large compound eyes face forward and overlap, giving the mantis genuine stereoscopic depth perception, rare in insects. It knows precisely how far away its target is.
• The neck. A mantis can turn its head up to 180 degrees — the only insect able to look behind itself — so it can track prey and scan for threats without betraying its position by moving.
• The strike. The raptorial forelegs, normally folded in the “praying” posture, shoot out and snap shut in 50–70 milliseconds. Rows of sharp spines pin the prey, and the mantis begins eating immediately, often while the victim is still alive.

Larger mantises take prey well above their weight class, including spiders, small lizards, frogs, and, occasionally, hummingbirds caught at feeders and flowers.

The single ear

Most mantises have a single ear, set in a groove on the underside of the thorax between the hind legs. It is not tuned to the sounds of other mantises but to ultrasound — specifically the echolocation calls of hunting bats. A mantis in flight that hears a bat closing in throws itself into a spiralling power dive to escape, a last-second defence that has been filmed in slow motion.

Reproduction

In autumn, the female lays her eggs in a frothy secretion that she whips up with her abdomen; it hardens into a tough, weatherproof case called an ootheca containing 100 to 400 eggs, glued to a twig or wall. In many species she then dies with the first frost, and the young hatch out together in spring as miniature wingless versions of the adult.

Sexual cannibalism — the female eating the male during or after mating — is real but far from universal. It occurs in a minority of matings even in the species famous for it, is more common when the female is hungry, and, when it happens, boosts her egg production. Males in those species approach slowly, from behind, and time their advance to when the female is distracted by feeding.

Conservation

Mantodea has not been assessed as a family, and most species are common and secure. Localised threats are the familiar ones for insects — habitat loss, pesticide use, and, for some spectacular tropical species, over-collection for the pet trade. A few flower-mimicking and forest specialists are of conservation concern where their specific habitats are being cleared.