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Defense and Attack Strategies and Mechanisms in Biology 359

hydrogen peroxide to water and oxygen) and peroxidase are stored in an accessory chamber. When
the beetle is disturbed, these compounds are mixed. This produces a strongly exothermic reaction
that generates quinines, discharged as a vapour of about 1008C, an effective deterrent against
predators. The emission occurs as a pulsed jet rather than as a steady stream that allows for a higher
discharge velocity due to increased pressure in the reaction chamber (Dean et al., 1990).

Many compounds in these beetles have been implicated as toxins or feeding deterrents against
predators; the secretions are usually mixtures of a number of components. Some surfactant
components may help the toxic compounds penetrate the skin of a predator.
Amongst sea birds, fulmars are well-known masters of the art of projectile vomiting. Also they
are exceptionally courageous and will stay by their single egg if people come close. They are mostly
silent apart from a low cackling noise made to other fulmars. So the first a person may know of the
presence of a fulmar is a stream of foul and evil-smelling orange vomit spewing straight into their
eyes from a few feet away. Even a young fulmar chick can do this.
Spitting cobras also figure here among projectile vomitters.

13.11 OPERATIONAL

13.11.1 Long-Term Disablement

The outcome of the application of nonlethal force that affects the opponent beyond duration of the
confrontation or conflict. Blinding, maiming or psychologically deranging the opponent represent
forms of long-term disablement. This form of disablement burdens a society and is anathema to the
Western definition of nonlethality (Alexander et al., 1996).
Few animal encounters end with disablement — the tendency is for the victor to eat the
vanquished. This is not true of herbivores, of course, when the fight will be in dispute of territory
or reproductive access to a harem. Deer, whose antlers grow afresh every year, can cope with the
30% breakage which results from fights in the rutting season (Kitchener, 1987), although they may
get wounded on the flank. On the other hand, sheep, goats, and antelope, whose horns grow from the
root and are not renewed annually, lose the ability to fight if the horn is broken and thus cease to
be reproductively active. It is likely that only amongst elephants and cetaceans is there any care
for the disabled; social carnivores (wolves, lions, wild dogs) also show some concern. Otherwise
the injured die and are no further burden.

13.11.2 Passive Deterrents

Non-lethal weapons that do not affect the physiology of the target individual. Includes dyes,
personal alarms, and scent sprays (Alexander et al., 1996).
The best-known animal using a similar technique is the striped skunk that has about a table-
spoonful of oily yellow musk in its scent glands located at its anus. This will produce five or six
sprays, each of which is accurate and can travel up to 5 m. The mist from the spray can travel 10 to
15 m with the smell carrying up to 2 km. A great many insects produce repellant chemicals (q.v.).

13.12 PHYSIOLOGICAL

13.12.1 Neurochemical

There are many neurotoxins. For instance, a sea anemone uses its tentacles to capture prey and
defend itself against predators. Every tentacle is covered with thousands of tiny stinging capsules