Stick Insect
Built to be mistaken for the plant it is sitting on. Many species manage without males at all: the females lay eggs that hatch into more females.
Photo by gailhampshire, CC BY 2.0
Overview
Stick insects are built around one idea, which is not being seen. The body is a twig, the legs fold flat along it, and a disturbed one holds still and sways slightly, as though the branch it is on has caught the wind.
Plenty of species manage without males at all. The Indian stick insect, Carausius morosus, is the standard example: females lay unfertilised eggs that hatch into more females, generation after generation, which is how one insect in a school biology room becomes a colony by the end of term. Eggs take anywhere from two months to a year to hatch depending on the species, so patience is part of the deal.
Temperament
Slow, calm, and easy to hold if you let them walk on rather than picking them up. Legs come off more readily than people expect, and while a nymph regrows one at its next moult, an adult has finished moulting and keeps the injury.
A few species are less placid than the Indian. Thorn legged stick insects can pinch with the hind legs, and some species spray a defensive chemical when they are grabbed, which is worth knowing before one gets handed to a child.
Care and grooming
Bramble is the staple. Blackberry and its relatives feed nearly every species in the hobby, oak and hawthorn cover most of the rest, and the fern eaters are the exception rather than the rule. Cut stems stand in water with the neck blocked so nothing climbs in and drowns.
Pick leaves away from roadsides, where fumes settle on them, and rinse anything you are unsure about. The insect eats nothing else and has no way of avoiding whatever is on the leaf.
Living and exercise
The cage wants to be about three times the adult length in height. They moult hanging from the top, and one that runs out of room underneath comes out deformed or does not get out at all.
Mesh sides beat glass, because they need something to grip. Mist in the evening rather than the morning, which is when most of them drink, and match the humidity to the species: the Indian is content at ordinary room temperature and humidity, while several tropical ones want close to 80 percent and a good deal more warmth.
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