A bowler reaches his delivery stride by means of a "run-up" and an over is deemed to have begun when the bowler starts his run-up for the first delivery of that over, the ball then being "in play". Fast bowlers, needing momentum, take a lengthy run up while bowlers with a slow delivery take no more than a couple of steps before bowling. The fastest bowlers can deliver the ball at a speed of over 145 kilometres per hour (90 mph) and they sometimes rely on sheer speed to try to defeat the batsman, who is forced to react very quickly. Other fast bowlers rely on a mixture of speed and guile by making the ball seam or swing (i.e. curve) in flight. This type of delivery can deceive a batsman into miscuing his shot, for example, so that the ball just touches the edge of the bat and can then be "caught behind" by the wicket-keeper or a slip fielder. At the other end of the bowling scale is the spin bowler who bowls at a relatively slow pace and relies entirely on guile to deceive the batsman. A spinner will often "buy his wicket" by "tossing one up" (in a slower, steeper parabolic path) to lure the batsman into making a poor shot. The batsman has to be very wary of such deliveries as they are often "flighted" or spun so that the ball will not behave quite as he expects and he could be "trapped" into getting himself out. In between the pacemen and the spinners are the medium paced seamers who rely on persistent accuracy to try to contain the rate of scoring and wear down the batsman's concentration.
Other defensive strategies are the use of camouflage, fleeing, and aggression. Some species have adopted colourings, shapes, and patterns that make it difficult for predators that hunt by sight to detect them. They tend to be dull shades of brown, grey, and green that blend into their background, and desert species tend to be pale. Some species can fly, but the mode of flight tends to be clumsy, so the most usual response to danger is to scuttle away to find a hiding place.
Cricket is a bat-and-ball game played on a cricket field (see image, right) between two teams of eleven players each. The field is usually circular or oval in shape and the edge of the playing area is marked by a boundary, which may be a fence, part of the stands, a rope, a painted line or a combination of these; the boundary must if possible be marked along its entire length.
Male crickets establish their dominance over each other by aggression. They start by lashing each other with their antennae and flaring their mandibles. Unless one retreats at this stage, they resort to grappling, at the same time each emitting calls that are quite unlike those uttered in other circumstances. When one achieves dominance, it sings loudly, while the loser remains silent.
Captive crickets are omnivorous; when deprived of their natural diet, they accept a wide range of organic foodstuffs. Some species are completely herbivorous, feeding on flowers, fruit, and leaves, with ground-based species consuming seedlings, grasses, pieces of leaf, and the shoots of young plants. Others are more predatory and include in their diet invertebrate eggs, larvae, pupae, moulting insects, scale insects, and aphids. Many are scavengers and consume various organic remains, decaying plants, seedlings, and fungi. In captivity, many species have been successfully reared on a diet of ground, commercial dry dog food, supplemented with lettuce and aphids.