Many organisms develop unique structures and behaviours to allow them to reproduce successfully in their environment. In the class Insecta, there are many orders with elaborate and unique mating structures and mechanisms. The order Orthoptera includes grasshopper, Locusts, crickets and katydids. The defining characteristic for this order is during courtship and mating, some Orthoptera will produce acoustic sounds when trying to find a mate. The acoustic sound is produced by stridulation, which is not only used to attract mates but to also claim territory and sound alarms. To assist each species in recognising each other Orthopterans have developed complex and elaborate songs (Kriegbaum and Helversen 2010). Not all Orthopterans use only acoustic sounds as some are also known to use pheromones and external markings to attract mates (Kriegbaum and Helversen 2010). This website will focus on the structures of the acoustic mechanisms that have an impact on the behaviour of grasshoppers. |
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In the order Orthoptera, there are around 20 000 known species (Gullan and Cranston 2005). These species reside in most environments except extremely cold areas, and best develop in the tropics (Capinera, 2008). Most Orthopterans are solitary until mating season (Net Industries, 2012) but there are some species that aggregate. For example locusts, which are a group of grasshoppers, have distinctive behavioural differences due to their nature of forming swarms (Ingrisch and Rentz 2009). Orthopterans are mainly composed of herbivorous and some omnivorous species, interestingly the herbivorous species are sometimes specialised to survive on a specific plant (The University of Arizona 1997). Predators of the Orthopterans include birds, lizards, mantids, spiders and rodents (The University of Arizona 1997). The Orthopterans are hypognathous, meaning they have a lower jaw that protrudes beyond the upper jaw (Gullan and Cranston 2005). They also have enlarged hind legs for jumping great distances (Gullan and Cranston 2005). The Orthoptera also commonly share a characteristic during their life cycle, this is the juvenile stage called a nymph (Gullan and Cranston 2005). The nymph resembles a smaller adult that cannot reproduce and has no developed wings (Gullan and Cranston 2005).