Termite Biology And Ecology

Termites live in colonies that are social and can be long-lived. Colonies are composed of castes that conduct all tasks for survival (Figs. 1, 2, and 3). Some termite queens are larger than the length of a human thumb and can lay more than a thousand eggs per day. The king is also long-lived and mates intermittently to provide sperm to the queen. Some of the longest living insects are termites some termite mounds and their queens are thought to be more than 70 years old and Aborigine folklore...

Morphology

Because of the structural variety in Diptera, especially among larvae, it is difficult to generalize about morphology. Despite this variety, flies share a number of features. Except for certain forms (e.g., cave-dwelling species), adult flies usually possess large compound eyes. In some species, eyes meet or almost meet dorsally (holoptic) in other groups, eyes are widely separated (dichoptic). Further modifications include eyes that are divided into distinct dorsal and ventral components, a...

Biological Control Through Augmentation

Pros and Cons of Augmenting Natural Enemies Entomologists and farmers, working together, have developed methods to rear some species of predators and parasitoids that attack pest insects. This approach of deliberately rearing natural enemies and releasing them against target pests has been applied against insects and mites of both greenhouse and outdoor crops. The use of this practice in greenhouse-grown tomatoes was begun in the 1920s with the rearing by English growers of Encarsia formosa, a...

Major Groups And Host Affiliations

Aphids, as the superfamily Aphidoidea, belong to the Sternorrhyncha within the Hemiptera, a group they share with Aleyrodoidea (whiteflies), Psylloidea (jumping plant lice), and Coccoidea (scale insects and mealybugs). Aphidoidea has three families Adelgidae (adelgids), Phylloxoridae (phyllox-orids), and Aphididae (aphids), although some workers place the Adelgidae and Phylloxoridae in a separate superfamily, Phylloxoroidea. Adelgids and phylloxorids are primitive aphids and older groups, each...

Nontympanal Hearing Organs

Until now we have focused on tympanal ears, which are sensitive to traveling waves of changing pressure in air and water, known as the acoustic far field. In the broadest sense of the word, however, hearing encompasses the detection of near-field sounds, as well as vibrations traveling through solid substrates. By and large, the near field can be thought of as a short distance, a few body lengths, from the sound source. Substrate vibrational signals have also been described as seismic...

Modes Of Foundation Independent Swarming And Budding

Size versus number of propagules Insect colonies vary widely in the amount of investment they make in each of their offspring colonies. At the low end are independently founded colonies, wherein single inseminated females (such as eusocial thrips and aphids and some Hymenoptera) initiate new colonies alone. In these species, the colony passes through a solitary phase. Examples of independent founders include sweat bees (Halictidae), bumble bees (Bombus), several genera of paper wasps most...

The Protocerebrum

The ground structure of the protocerebrum suggests its ancestral affinities with segmental ganglia. In the protocerebrum, as in postoral ganglia, ascending sensory interneuron tracts enter it ventrally, whereas premotor interganglionic interneurons exit dorsally. Afferents (here the optic lobe output neurons see later) distribute to local interneurons in a manner reminiscent of sensory afferents within postoral ganglia. Despite its basic similarities with segmental ganglia, the protocerebrum...

Songs And Communication

In most cricket species the males chirp or trill, producing clear, rhythmic, musical sounds distinctive to their family. An upturned scraper on one forewing is rubbed along a row of fewer than 10 to more than 1300 teeth, on the underside of the other forewing tooth number, often species-specific, correlates with pulse rate and length. The dominant frequency in the sound depends upon the tooth-strike rate, FIGURE 4 Drawings from audiospectrographs of the songs of 7 of the 17 known species of...

Discovery And Characterization Of Cave Arthropods

Why an animal would abandon the lighted world and lose such adaptive characters as eyes, pigment, and dispersal ability to live permanently in perpetually damp, dark, barren caves has long fascinated both biologists and laymen. In fact, it is these pale, blind obligate cave species that one usually envisages under the rubric of cave animal, and it is this group that is featured in this article. However, numerous other animals live all or part of their life cycles in caves or are regular...

Insects As Omens And Soothsayers

Insects that are most commonly featured in human folklore are those that most closely associate with humans or impact human affairs. It is not surprising then that insects such as cockroaches, mosquitoes, and bees are some of the most common subjects in stories and superstitions in which an insect's presence or activity is related to significant events in people's lives. Because humans have practiced honey hunting and beekeeping for thousands of years, it is not surprising that there is much...

Biological Control of Insect Pests

University of Massachusetts, Amherst Biological control is a form of pest control that uses living organisms to suppress pest densities to lower levels. It is a form of ecologically based pest management that uses one kind of organism (the natural enemies) to control another (the pest species). Types of natural enemies vary with the type of pest. For example, populations of pest insects such as scales are often suppressed by manipulating populations of parasitoids, which are insects that...

Natural Enemy Conservation Concept of Natural Control

All insects and plants, to various degrees, are attacked by natural enemies independent of any deliberate manipulations by people. Such natural control is rarely sufficient to suppress an invasive species the local natural enemies lack specialized relationships to the invader, since by definition, the new pest is outside the evolutionary experience of the prey species. For native species, however, natural control may suppress plants and insects below pest levels. Also, for invasive species...

Stingless Bees Meliponinae in the Tropics

In the Old World tropics, much more honey could be obtained from honey bees than from stingless bees, and the latter were seldom used for beekeeping. But in the Americas, where there were no honey bees, hive beekeeping was developed especially with the stingless bee, Melipona beecheii, a fairly large species well suited for the purpose. It builds a horizontal nest with brood in the center and irregular cells at the extremities, where honey and pollen are stored. The Maya people in the Yucatan...

Marketing Insects In The Environment

A more nebulous category of insect commercialization surrounds the marketing of insects in the wild. Bioprospecting, ecotourism, and conservation enhancement are modes through which insects are marketed in an environmental context. These modes frequently interact to serve the broader intent of environmental protection. Biodiversity prospecting involves the exploration, extraction, and screening of commercially valuable genetic and biochemically active compounds of plants, arthropods, and...

Partnership In Pest Control 1880 To World War I

The institutional framework for colleges of agriculture was well established by 1880. The first department of entomology was founded at Cornell University in 1874 under the leadership of John Henry Comstock others followed shortly. The primary objective of the department was to train students who wished to become farmers, to identify and classify the insect fauna, to study life cycles, to devise control measures, and to train farmers in their use. As insecticides became a more important...

Inflammatory And Immune Responses

When feeding from the host skin surface, acarine parasites inject or secrete into the host an array of immunogenic and pharmacokinetic molecules. Likewise, acarine parasites that live in the skin, hair follicles, sebaceous glands, and respiratory tree and lungs release immunogenic molecules both while living and after death, from their disintegrating bodies. Substances injected or released may induce an inflammatory (i.e., innate) and or immune (i.e., adaptive) response by the host....

Art Language And Literature

Art draws its inspiration from the environment of the artist. It is therefore not surprising that insects have pervaded all forms and aspects of art. Images of insects are found as adornment on all types of objects from textiles and pottery to weapons and jewelry and even the tattoos on human bodies. Insects are also found, either as the primary subjects or merely as curious elements of lesser status, throughout all types of paintings. Like the illustration of other animals, insect illustration...

Important Families Of Termites

The earliest known fossil termites date to the Cretaceous, about 130 mya. There are > 2600 species of termites worldwide. Undoubtedly, more will be recognized with improved methods of discerning cryptic species and after intensive collecting of tropical and remote regions. Termites are most closely related to cockroaches and mantids. The greatest continental termite diversity is in Africa, where there are over 1000 species. Polar continents have none, and North America with 50 species and...

Emergence

Emergence, the transition from the aquatic nymph to the terrestrial subimago, is a critical period for mayflies. Their movement up to the water surface makes them especially vulnerable to aquatic and aerial predators. Shedding of the nymphal skin usually occurs at the water surface on some object, such as a stone or macrophyte stem, or in midwater. FIGURE 2 Mayfly nymphs (A) Baetis subalpinus (family Baetidae), (B) Ephemera danica (family Ephemeridae), (C) Ephemerella mucronata (family...

Foregut

FIGURE 1 A diagrammatic representation of the insect gut. Malpighian tubules, and the structures in the hindgut, namely the ileum and rectum (Fig. 1). The midgut is a tubular epithelium. Upon ingestion, food and fluids move through the esophagus and pass directly into the midgut. Because the cells in the midgut epithelium are derived from embryonic endoderm, the midgut is not lined with cuticle. Most of the cells in the midgut are involved in the secretion of digestive fluids and the absorption...

Plasticity In Colony Division Of Labor

Colony division of labor, though highly structured, also shows great plasticity. Colonies respond to changing needs by adjusting the ratios of individual workers engaged in different tasks. This is a consequence of the flexibility of the individual workers. For example, there is plasticity in age-related division of labor, with workers able to respond to changes in colony age demography with accelerated, retarded, or reversed behavioral development. Workers also can shift to emphasizing a...

Symbolism And Reverence

Throughout human existence, many insects have been admired for their ingenuity, beauty, fantastic shapes, and behaviors. In some instances, the use of insects as totemic figures that may symbolize ancestry or kinship of humans with these organisms leads to a deep sense of adoration and reverence. In other cases, the resultant admiration has developed into a reverence for their inspirational and historical nature and a medium for symbolizing a variety of aspects of human life. In these...

Entomology Postworld War Ii Technologys Triumph

The explosion of the atom bomb over Nagasaki in 1945 brought a dramatic end to World War II and in so doing, highlighted the role of science and technology in the victory. Following this, the age-old ritual of beating swords into plowshares turned scientific and technical advances to peaceful ends. No field emerged with more exciting prospects than did the field of entomology. DDT, with its wartime secrecy removed, was hailed as the answer to insect control. Its employment in arresting an...

Variety Of Salivary Defensive Functions Salivary Venoms

The spitting cobra, Naja nigricollis, has an insect parallel, both in terms of the general chemistry of the saliva and the ability to accurately fire the venom at a moving target. For example, Platymeris rhadamanthus is a black and orange assassin bug (Reduviidae) that is very conspicuous because of its aposematic (warning) coloration. This insect can eject its saliva for a distance up to 30 cm, and if this enzyme-rich solution (proteases, hyaluronidase, phospholipase) strikes the nose or eye...

Larval Specialization

Micromalthus Debilis

Among the four suborders of Coleoptera, life histories of the predaceous Adephaga most closely resemble those of the beetles' phylogenetic sister group, the neuropteran orders. Adephagan larvae are generally campodeiform, that is, elongate and slightly dorsoventrally flattened, with long thoracic legs and a posteriorly tapered, dorsally sclerotized abdomen (Fig. 13). They typically have anteriorly directed mouthparts that often include elongate, sickle-shaped mandibles with a reduced mola (Fig....

Overview Of The Phylum Arthropoda

The Arthropoda is a phylum more diverse than any other living or extinct animal taxon. Counted among this immense assemblage are beetles, butterflies, silverfish, centipedes, scorpions, mites, sea spiders, crabs, sow bugs, and barnacles, and many other common names too numerous to mention. Arthropods are the numerically dominant metazoan on land and rank among the most prominent benthic (bottom-dwelling) and planktonic members of freshwater and marine ecosystems. They colonize virtually every...

Division Of Labor Among Workers

In most insect societies there also is a division of labor among the workers for tasks related to colony growth and maintenance. The evolution of a highly structured worker force is generally seen as an evolutionary consequence of the developmental divergence between queens and workers. Once workers were limited to serving largely as helpers, their characteristics could be shaped further by natural selection acting at the level of the colony to increase colony fitness. This perspective is...

General Characteristics And Terminology

Hypermetamorphosis Insect

Two broad categories of hypermetamorphosis can be recognized in insects. In the most widespread form, there is a decoupling of oviposition site and the larval food in the other, the oviposition and larval feeding sites are identical. For convenience, these can be referred to as type I and type II hypermetamorphosis, respectively. Type I adult females do not oviposit directly at the larval feeding site instead, the first instars must find the food source. Such larvae are active, slender, and...

Classical Biological Control Ecological Justification

People routinely move species such as crop plants and ornamentals across natural barriers such as mountain ranges or oceans that would otherwise limit their spread. These plants may carry with them small, unrecognized infestations of pest insects. In some cases, the plants themselves may spread and become damaging. Both invasive plants and insects often escape their specialized natural enemies when they cross geographic barriers and establish in new locations. This allows these species to reach...

Digging Leg Of The Mole Cricket

Fossorial Legs

The majority of insectan legs are either elongate, slender, and designed for walking and climbing or cursorial, i.e., adapted for running, as in the cockroach Fig. 1A . During walking, the legs form alternating triangles of support, with the fore and hind legs of one side and the middle leg of the opposite side contacting the substrate as the other three legs move forward. Various modifications allow the legs to be used in other forms of locomotion. Enlarged hind legs of many Orthoptera, fleas,...

Traditional Movablecomb Hive Beekeeping

Movable-comb hive beekeeping was a crucial intermediate step between fixed-comb beekeeping, which had been done in many parts of the Old World, and the movable-frame beekeeping used today. In a book published in 1682 in England, Sir George Wheler recounted his journeys in Greece and provided details of the hives he saw there Fig. 3 . He described the wooden bars shown lying across the top of the hive as broad, flat sticks and said that the bees built a comb down from each top-bar, which may be...

The Genus Drosophila As A Model System

In addition to referring to the single species D. melanogaster, Drosophila can also refer to the entire genus Drosophila, a spectacular radiation of roughly 1500 described species. This genus can be found throughout the world in every conceivable habitat, from tropical rain forests to subarctic regions. Generally, these species are saprophytic, feeding and ovipositing in rotting plant and, sometimes, animal material. Members of this genus have been used as a model system for understanding...

Morphology Adult

Moth Anatomy

The body framework Fig 2 consists of a hardened sclerotized exoskeleton made up of a head capsule with appendages three fused thoracic segments, each with legs, and two pairs of wings, on the middle mesothoracic and third metathoracic segments and an abdomen, which has 10 segments, is less sclerotized than the thorax, and is movable by intersegmental membranes. Complex genital structures of external origin arise from abdominal segments A8-10, and often there are accessory structures pouches,...

Economic Importance Injurious Families

Injurious Domestic Animals

Several families of Diptera are of major economic importance and involved in the transmission of more disease pathogens to humans and other animals than any other group of arthropods. Biting flies cause annoyance that impacts tourism, recreation, land development, and industrial and agricultural production, whereas their effects on livestock can cause reduced milk, egg, and meat production. The adults have mouthparts that have very effective piercing stylets, enabling these flies to bite and...