Vision (Insects)

Vitellogenesis Vitellogenesis is the process by which yolk accumulates in the cytoplasm of an ovarian oocyte. It is one of the final stages of egg formation, occurring just prior to deposition of the cho-rion. Studies on vitellogenesis have focused during the last 50 years on the major protein yolk precursor, vitellogenin, its synthesis in the […]

Vinegaroons (Insects)

First human-vinegaroon encounters evoke a natural human response: “what a bizarre animal,” “is this thing real, or did someone cobble together various parts from nature? “Is it from outer space?” No, vinegaroons are real, live, arthropods, and not extraterrestrial, albeit extremely ancient. They were around during the Carboniferous era, about 350 mya, and have remained […]

Vibrational Communication (Insects)

Many insects communicate by mechanical signals propagating through a medium as near- or far-field airborne sound, substrate vibrations, underwater sound, and/or water surface vibration. Vibrational signaling through substrate is most commonly used whether counted by species, family or phylogenetic distribution (Fig. 1). Over 195,000 species communicate with substrate-borne signals alone or together with other forms […]

Veterinary Entomology (Insects)

Veterinary entomology deals with arthropod pests and vectors of disease agents to livestock, poultry, pets, and wildlife. It is T allied with the fields of medical entomology, parasitology, animal sciences, veterinary medicine, and epidemiology. The main pests of veterinary concern are sucking and biting lice, biting flies, nonbit-ing muscoid flies, bot flies, fleas, and Acari […]

Venom (Insects)

Venoms are biologically active liquids delivered into or onto another organism through a piercing structure such as a mouthpart or sting apparatus and often resulting in pain, tissue damage, paralysis, or death in the target organism. Insects contain more venomous species than all other groups of terrestrial animals combined. Within insects, venoms evolved numerous times […]

Tsetse Fly (Insects)

Tsetse flies belong to the single genus Glossina, in the family Glossinidae of the order Diptera. They are found only in sub-Saharan Africa, Yemen, and Saudi Arabia, infesting 38 countries and occupying about 11 million square kilometers. As cyclical vectors of protozoan parasites of the genus Trypanosoma, they are of major economic and biological importance. […]

Urban Habitats (Insects)

Urban environments are created from natural or agricultural ecosystems that have been disturbed by human activities, typically by the construction of towns and cities. The urban biotic environment can be divided into plant and animal communities that surround houses and buildings, occur indoors or in close contact with humans, or directly affect the structure. Human […]

Trichoptera (Caddisflies) (Insects)

Trichoptera, or caddisflies, are holometabolous insects closely related to Lepidoptera, or moths. However, unlike most moths, their eggs, larvae, and pupae are usually found in or very near freshwater, and adults are aerial, usually not far from their aquatic habitats (Fig. 1) . The Trichoptera include more species than any of the other primarily aquatic […]

Touch (Insects)

Tracheal System Insects have a tracheal respiratory system in which oxygen and carbon dioxide travel primarily through air-filled tubes called tracheae. Usually the tracheal system penetrates the cuticle via closeable valves called spiracles and ends near or within the tissues in tiny tubes called tracheoles (Fig. 1). The tracheae primarily serve as pipes that transport […]

Thysanura (Insects)

Ticks Ticks comprise a distinct group of exclusively blood-feeding ectoparasites familiar to most people in virtually all regions of the world. Ticks transmit a greater variety of disease-causing pathogenic agents than any group of arthropods, including protozoan, viral, bacterial, and even fungal pathogens. An example is Lyme disease (LD), which is now the most important […]