Crickets are hemimetabolic insects, whose lifecycle consists of an egg stage, a larval or nymph stage that increasingly resembles the adult form as the nymph grows, and an adult stage. The egg hatches into a nymph about the size of a fruit fly. This passes through about 10 larval stages, and with each successive moult, it becomes more like an adult. After the final moult, the genitalia and wings are fully developed, but a period of maturation is needed before the cricket is ready to breed.
The other ICC full members have national championship trophies called the Ahmad Shah Abdali 4-day Tournament (Afghanistan); the National Cricket League (Bangladesh); the Ranji Trophy (India); the Inter-Provincial Championship (Ireland); the Plunket Shield (New Zealand); the Quaid-e-Azam Trophy (Pakistan); the Currie Cup (South Africa); the Premier Trophy (Sri Lanka); the Shell Shield (West Indies); and the Logan Cup (Zimbabwe).
Most bowlers are considered specialists in that they are selected for the team because of their skill as a bowler, although some are all-rounders and even specialist batsmen bowl occasionally. The specialists bowl several times during an innings but may not bowl two overs consecutively. If the captain wants a bowler to "change ends", another bowler must temporarily fill in so that the change is not immediate.
While the umpire (1) in shot stands at the bowler's end of the pitch, his colleague stands in the outfield, usually in or near the fielding position called "square leg", so that he is in line with the popping crease (7) at the striker's end of the pitch. The bowling crease (not numbered) is the one on which the wicket is located between the return creases (12). The bowler (4) intends to hit the wicket (9) with the ball (5) or, at least, to prevent the striker (8) from scoring runs. The striker (8) intends, by using his bat, to defend his wicket and, if possible, to hit the ball away from the pitch in order to score runs.
If the match has only a single innings per side, then a maximum number of overs applies to each innings. Such a match is called a "limited overs" or "one-day" match, and the side scoring more runs wins regardless of the number of wickets lost, so that a draw cannot occur. If this kind of match is temporarily interrupted by bad weather, then a complex mathematical formula, known as the Duckworth-Lewis method after its developers, is often used to recalculate a new target score. A one-day match can also be declared a "no-result" if fewer than a previously agreed number of overs have been bowled by either team, in circumstances that make normal resumption of play impossible; for example, wet weather.
The phylogenetic relationships of the Gryllidae, summarized by Darryl Gwynne in 1995 from his own work (using mainly anatomical characteristics) and that of earlier authors,[a] are shown in the following cladogram, with the Orthoptera divided into two main groups, Ensifera (crickets sensu lato) and Caelifera (grasshoppers). Fossil Ensifera are found from the late Carboniferous period (300 Mya) onwards, and the true crickets, Gryllidae, from the Triassic period (250 to 200 Mya).
Some species of cricket are polyandrous. In Gryllus bimaculatus, the females select and mate with multiple viable sperm donors, preferring novel mates. Female Teleogryllus oceanicus crickets from natural populations similarly mate and store sperm from multiple males. Female crickets exert a postcopulatory fertilization bias in favour of unrelated males to avoid the genetic consequences of inbreeding. Fertilization bias depends on the control of sperm transport to the sperm storage organs. The inhibition of sperm storage by female crickets can act as a form of cryptic female choice to avoid the severe negative effects of inbreeding. Controlled-breeding experiments with the cricket Gryllus firmus demonstrated inbreeding depression, as nymphal weight and early fecundity declined substantially over the generations' this was caused as expected by an increased frequency of homozygous combinations of deleterious recessive alleles.
In 1975, Dr. William H. Cade discovered that the parasitic tachinid fly Ormia ochracea is attracted to the song of the cricket, and uses it to locate the male to deposit her larvae on him. It was the first known example of a natural enemy that locates its host or prey using the mating signal. Since then, many species of crickets have been found to be carrying the same parasitic fly, or related species. In response to this selective pressure, a mutation leaving males unable to chirp was observed amongst a population of Teleogryllus oceanicus on the Hawaiian island of Kauai, enabling these crickets to elude their parasitoid predators. A different mutation with the same effect was also discovered on the neighboring island of Oahu (ca. 100 miles (160 km) away). Recently, new "purring" males of the same species in Hawaii are able to produce a novel auditory sexual signal that can be used to attract females while greatly reducing the likelihood of parasitoid attack from the fly.
Subject to certain variations, on-field clothing generally includes a collared shirt with short or long sleeves; long trousers; woolen pullover (if needed); cricket cap (for fielding) or a safety helmet; and spiked shoes or boots to increase traction. The kit is traditionally all white and this remains the case in Test and first-class cricket but, in limited overs cricket, team colours are worn instead.