Search results
Results from the WOW.Com Content Network
Most phylogenetically advanced insects have two pairs of wings located on the second and third thoracic segments. [1]: 22–24 Insects are the only invertebrates to have developed flight capability, and this has played an important part in their success. Insect flight is not very well understood, relying on turbulent aerodynamic effects. The ...
The thoracic segments have one ganglion on each side, which are connected into a pair, one pair per segment. This arrangement is also seen in the abdomen but only in the first eight segments. Many species of insects have reduced numbers of ganglia due to fusion or reduction. [8]
Two thoracic segments are fused into the head; one thoracic segment is in the posterior tagma. Other kinds of copepod also have two tagmata but formed by different segments. The development of distinct tagmata is believed to be a feature of the evolution of segmented animals, especially arthropods. In the ancestral arthropod, the body was made ...
In hymenopterans of the suborder Apocrita (wasps, bees and ants), the mesosoma consists of the three thoracic segments and the first abdominal segment (the propodeum). For historical reasons, in ants it is commonly referred to by the alternative name alitrunk. [1] [2] [3]
Insect wings are adult outgrowths of the insect exoskeleton that enable insects to fly.They are found on the second and third thoracic segments (the mesothorax and metathorax), and the two pairs are often referred to as the forewings and hindwings, respectively, though a few insects lack hindwings, even rudiments.
Abdominal segments three through six and ten may each bear a pair of legs that are more fleshy. [21] The thoracic legs are known as true legs and the abdominal legs are called prolegs. [64] The true legs vary little in the Lepidoptera except for reduction in certain leaf-miners and elongation in the family Notodontidae.
All adult insects possess legs on the mesothorax. In some groups of insects, the mesonotum is hypertrophied, such as in Diptera , Hymenoptera , and Lepidoptera ), in which the anterior portion of the mesonotum (called the mesoscutum , or simply "scutum") forms most of the dorsal surface of the thorax.
Figure 1 - Mutations in the Ubx gene lead to transformation of appendages in T2 and T3 segments, resulting in a second set of wings observed in the "bithorax" phenotype. Ultrabithorax (Ubx) is a homeobox gene found in insects, and is used in the regulation of patterning in morphogenesis .