Entomology
Introduction
Entomology is the scientific study of insects, a branch of zoology. In the past the term "insect" was more vague, and historically the definition of entomology included the study of terrestrial animals in other arthropod groups or other phyla, such as arachnids, myriapods, earthworms, land snails, and slugs. This wider meaning may still be encountered in informal use.
Etymology
The word entomology comes from the Greek ἔντομον, éntomon, meaning "cut into pieces" or "engraved/segmented", hence "insect"; and -λογία, -logia, "the study of". The word entomology is therefore similar to the word "insect" in origin, both deriving from the notion of a small, segmented animal.
History
Entomology is rooted in nearly all human cultures from prehistoric times, primarily in the context of agriculture (especially biological control and beekeeping). The natural philosopher Pliny the Elder, (23 - 79 AD) wrote a book on the kinds of Insects, while the scientist of Kufa, Ibn al-A‘rābī (760 - 845 AD) wrote a book on flies, Kitāb al-Dabāb (كتاب الذباب). However, the formal study of insects began only in the 16th century.
Branches of Entomology
Entomology is broken down into a number of sub-disciplines:
- Insect morphology: the study and description of the physical form and external structure of insects.
- Insect ecology: the study of the interactions between insects and their environments.
- Insect physiology: the study of the internal physical function and processes of insects.
- Insect behavior: the study of the actions of insects and the mechanisms that influence such actions.
- Insect systematics: the study and classification of insect species.
- Insect genetics and evolution: the study of the genetic characteristics of insects and their variation and changes over time.
- Insect conservation: the study of the threats to insect species and their habitats and efforts to protect them.
- Insect pathology: the study of diseases in insects.
- Forensic entomology: the study of the use of insects in legal investigations.
- Agricultural and forest entomology: the study of the impact of insects on forests and crops and efforts to control harmful species.
- Medical and veterinary entomology: the study of the role of insects in causing or spreading disease in humans and animals.
- Apiculture: the study of bees and beekeeping.
- Sericulture: the study of silkworms and silk production.
Insect Morphology
Insects possess segmented bodies supported by an exoskeleton, a hard outer covering made mostly of chitin. The segments of the body are organized into three distinctive but interconnected units, or tagmata: the head, thorax, and abdomen. The head supports a pair of sensory antennae, a pair of compound eyes, and three sets of variously modified appendages that form the mouthparts. The thorax has six segmented legs and two or four wings. The abdomen (made up of eleven segments some of which may be reduced or fused) has most of the digestive, respiratory, and excretory organs.
Insect Ecology
Insects are integral to the ecological processes of the Earth. They play a critical role in the pollination of plants, the decomposition of organic materials, and the cycling of nutrients. They are a major part of the Earth's biodiversity and serve as a major food source for many animals. The study of insect ecology provides valuable insights into the interactions between insects, their environment, and other organisms.
Insect Physiology
The study of insect physiology includes the functions of the various organs and structures within insects. This includes the study of the circulatory, respiratory, nervous, muscular, digestive, and reproductive systems of insects. Insect physiology also includes the study of insect molecular biology and genetics.
Insect Behavior
Insect behavior is a complex and varied field. It includes the study of how insects interact with each other and their environments. This can include the study of insect mating behaviors, how insects find and consume food, how they avoid predators, and how they navigate their environment.
Insect Systematics
Insect systematics is the scientific study of the classification of insects. This includes the identification, nomenclature, and classification of species. Systematics uses data from many fields, including morphology, physiology, behavior, ecology, and genetics, to form a comprehensive understanding of insect relationships and evolution.
Insect Genetics and Evolution
Insect genetics is the study of the genetic material of insects and how it influences their characteristics, behaviors, and evolution. This can include the study of gene expression, genetic variation, and the structure and function of genes. Insect evolution is the study of the origins and changes of insect species over time.
Insect Conservation
Insect conservation is the study of the threats to insect species and their habitats and the efforts to protect them. This can include the study of habitat destruction, pollution, climate change, and invasive species. Conservation efforts can include habitat restoration, the establishment of protected areas, and the development of conservation plans for specific species or groups of species.
Insect Pathology
Insect pathology is the study of diseases in insects. This can include the study of the causes, diagnosis, progression, and treatment of diseases. Insect pathologists may also study the impact of diseases on insect populations and the role of insects in spreading diseases.
Forensic Entomology
Forensic entomology is the application of the study of insects to legal cases, often to help determine the time of death of a victim by examining the insects present on the body. Forensic entomologists may also study the life cycles and behaviors of insects to help solve crimes.
Agricultural and Forest Entomology
Agricultural and forest entomology is the study of the impact of insects on forests and crops. This can include the study of pest species and the development of methods to control them. It can also include the study of beneficial insects and how they can be encouraged or utilized in pest control.
Medical and Veterinary Entomology
Medical and veterinary entomology is the study of the role of insects in disease. This can include the study of how insects spread diseases, the life cycles of insect vectors, and the development of methods to control disease-spreading insects.
Apiculture
Apiculture is the study of bees and beekeeping. This can include the study of bee behavior, the production of honey, and the role of bees in pollination. It can also include the study of threats to bee populations and efforts to protect them.
Sericulture
Sericulture is the study of silkworms and the production of silk. This can include the study of silkworm biology, the cultivation of silkworms, and the process of silk production.