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Arthropod Behavior rT^in: BRAINS or AR THROPODS arc

A relatively small. An adult locust, for example, has approximately one million nerve cells to serve all its sensory and motor needs. Smaller insects have far fewer nerve cells. Nevertheless, insects are capable of surprisingly sophisticated behavior, which is evident in the way that they move, avoid predators, feed, mate, and care for their offspring.

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cold light, produced by a chemical reaction, shines through transparent cuticle male a/tout to pump sperm into female's sperm storage organ

Courtship and Mating

In most species of arthropod, the male and female need to mate before the female can lay her eggs. The sexes may simply meet at good feeding or egg-laying sites, or they may take a more active part in finding a suitable mate, attracting each other with songs, odors, and even light displays. At close range, courtship can be a complicated process. Insects may move their wings, legs, and antennae in certain ways, secrete pheromones, and give and receive nuptial gifts (usually pieces of food). Not all species have to mate, however. The females of many arthropod species are able to lay viable eggs without the need for males.

enlarged, toothed rn and dries Jit a round rivals thorax male a/tout to pump sperm into female's sperm storage organ cold light, produced by a chemical reaction, shines through transparent cuticle

A fk jhting Stag Beetles

Female arthropods arc often highly selective, which leads to competition and rivalry between males. Here, male stag beetles fight for access to females. The winner may throw the opponent on to its bach, and then mate with the female.

ALight Attraction

In some beetles, such as the Glowworm, I ┬┐ampyris noctiluca (above), females attract males of the same species by emitting flashes of light. In a few cases, females lure males of other species to eat them.

XiL iting Together

In many arthropods, sperm is transferred to the female indirectly. However, in insects (here, soldier beetles), copulation always takes place.

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