Defence

Not all animals use camoflage to try and hide themselves from predators. Many sport bright warning colours, while others are able to suddenly spread their wings and display markings to startle their enemies. Foul-smelling secretions are proved themselves to be a very successful defence weapon and some animals, including ghost insects, are ready to physically defend themselves.

Warning colours

We humans are familiar with this strategie in the case of the wasp. If we harrass a wasp it stings us, which is painful. The next time we see an black and yellow coloured insect we are more careful because we remember the last encounter and the pain which followed!

Stick insects:
Most stick insects prefer to hide themselves rather than attract attention. however some do draw attention to themselves though their bright colouring. These warning colours mean: "Look out, I am poisonous or unpleasant" - the second being more common in the case of phasmids. There are species who can sprey their attacker with a foul-smelling substance from up to 30cm away. The peruvian fern insect for example is very conspicuously coloured.

Ghost insects:
The technique of using warning colours is not so common in ghost insects - they don't usually have such striking colouring as stick insects. They are certainly a few multi-coloured types, but in general they are all a similar brown colour which serves them well for camoflage purposes.

Leaf insects:
Leaf insects are primarily green, and a browny-orange around the edges. They do not use warning colouring.

Warning symbols

In the animal kingdom, many animals attempt to impress or frighten their predators. Many buterflies have big eye-like circles on the upper side of their wings and when a predator appears, they snap open their wings in the hope that the predator will think the markings are the eyes of a bigger animal. Other animals try to appear bigger then they really are, for example lizards which 'inflate' themselves using skin pockets.

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Stick insects:
Some stick insect species have strickingly coloured and patterned wings. Pseudophasma rufipes has red wings which it can whip open in a flash if an attacker threatens it.

Ghost insects:
Ghost insects very rarely have warning symbols as they usually camoflage themselves..

Leaf insects:
This defence technique is never used by leaf insects as they are so well camoflaged!

Foul-smelling secretions

One good defence strategie is the use of foul smelling secretions which remain on the attacker's skin, or burn it's mouth when it tries to eat it's prey. Everyone knows the skunk and is wary of it! If you are sprayed by a skunk the odour lingers for days, and you can throw your clothes away! In America skunks are kept as pets because of their gentle and trusting nature. However for this to be possible the skunks nust first be operated on.

Stick insects:
The peruvian fern insect can secrete a very awful smelling substance. Whenever I have to handle this insect in the terranium the almost overpowering odour clings to my hands and I have to very thoroughly wash them several times.
There are many other types of stick insects which produce similar secretions.

Ghost insects:
This technique is not so wide spread with ghost insects as with stick insects. There are however few which are able to spray their attackers. An example is the species Extatosoma tiaratum which produces a relatively weak substance.

Leaf insects:
As with the warning markings, leaf insects have no need to secrete foul-smelling substances because they are so well camoflaged.

Physical defence

Ghost insects:
Ghost insects depend mostly on their camoflage to protct them from predators. When they are threatened however, they lift up their lower body and swing in up towards their head. The hind legs are now open like a pair of scissors. When the attacker gets caught between the legs, the insect snaps them at uneven intervals together. as the legs are covered in thorny spines, this can be painful, however not dangerous for humans. This defence technique can be observed in a terranium, with the species Heteropteryx dilatata. It can look quite impressive, as this species can grow up to 15cm long.