Mantis

Specialized hunters

Mantises are among the few insects that hunt visually — and they’re remarkable at it. Their raptorial forelegs are spring-loaded: a mantis can strike at prey in 30–50 milliseconds, faster than the prey can react. The forelegs lock prey against rows of inward-facing spines and pull it back to the chewing mouthparts.

The triangular head with its bulging compound eyes can rotate 180° — the only insect with this neck flexibility. Combined with stereoscopic vision (mantises are among the very few invertebrates with depth perception), they can pinpoint prey with precision more like a small bird of prey than a typical insect.

Sexual cannibalism, in context

The story that female mantises always eat their mates is a famous overstatement. The reality:

• Cannibalism happens in some species, some of the time — not universally.
• Many lab studies that “showed” cannibalism were biased by stressed, starved insects in unnatural conditions.
• In wild populations, cannibalism rates vary from 0% to about 30% depending on species and food availability.
• Hungry females are more likely to cannibalize; well-fed females usually don’t.

Decapitation may, however, increase mating success — the male’s reproductive movements are partly controlled by ganglia in the abdomen rather than the brain, and a headless male can in fact transfer more sperm.

Camouflage and mimicry

Mantises are masters of disguise. Different species mimic:

• Leaves — the dead-leaf mantis matches falling foliage so closely it’s invisible at rest.
• Flowers — the orchid mantis (Hymenopus coronatus) of Southeast Asia mimics tropical orchid flowers so convincingly that pollinators are drawn to it rather than to actual flowers, where they’re then ambushed.
• Sticks — long thin mantises imitate twigs.
• Bark — mottled brown camouflage on tree trunks.

The orchid mantis is unusual: it’s a predatory mimic, attracting prey to itself rather than hiding from predators.

A favorite garden ally

Mantises eat enormous quantities of garden pests — caterpillars, aphids, grasshoppers, beetles. Many gardeners purchase ootheca (egg cases) for placement in vegetable beds. One ootheca produces 100–200 nymphs in spring.

A caveat: mantises are indiscriminate predators. They eat beneficial insects too, including bees, butterflies, and other mantises (intra-species cannibalism is common in nymphs).

Hunting hummingbirds

Some larger mantis species (especially the introduced Chinese mantis Tenodera sinensis in North America) regularly catch and eat hummingbirds at backyard feeders. The mantis hides on a feeder, ambushes the hovering bird, and pulls it onto a perch to consume. Documented cases occur primarily in late summer when both predator and prey converge at sugar-water feeders.