Grasshoppers :: essays research papers

Grasshoppers are herbivorous insects of the suborder Caelifera in the order Orthoptera. To distinguish them from bush crickets or katydids, they are sometimes referred to as short-horn grasshoppers. Species that change colour and behaviour at high population densities are called locusts. The Characteristics of a Grasshopper The Grasshoppers have antennae that are almost always shorter than the body (sometime filamentous), and short ovipositors. These species that make easily heard noise usually do so by rubbing the hind femurs against the forewings or abdomen (stridulation), or by snapping the wing sin flight. Tympana, if present, are on the sides of the first abdominal segment. The hind femora are typically long and strong fitted for leaping. Generally they are winged, but hind winds are membranous while front wings (tegmina) are coriaceous and not fit for flight. Females are normally larger than males, with short ovipositors. They are easily confused with the other sub-order of Orthoptera Ensifea, but are different in many aspects, such as the segments in their antennae and structure of the ovipositor, as well as Ensiferans have antennae with at least 30 segments and Caelifera have fewer. In evolutionary terms, the spilt between the Caelifera and the Ensifera is no more recent than the Permo-Triassic boundary (Zeuner 1939) Their Diverstiry and range Recent estimates (Kevan 1982, GÃ ¼nther, 1980, 1992, Otte 1994-1995 subsequent literature) indicate some 2,400 valid Caeliferan Genera and about 11,000 valid species described to date. Many un-described species exist, especially in tropical wet forests. The Caelifera are predominantly tropical but most super families are presented world wide. Families The suborder Caelifera consists primarily of five major families: ? Acrididae (field Grasshoppers and locusts) ? Emuastacidae (tanaocerids) ? Tetrigidae (grouse locusts, pygmy grasshoppers, and pygmy locusts) ? Tridactylidae (pygmy mole crickets) The most important family is Acrididae consisting of about 10,000 species. The family is characterised by the short thickened antennae and relatively unmodified anatomy, they are visually more striking than othe Caelifera, die to the adult?