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Use Of DNA In Forensic Entomology
Forensic entomology has three sub-fields: urban, stored product and medico-criminal entomologies. This article focuses on medico-criminal entomology and how DNA is analyzed with various blood-feeding insects. Forensic entomology can be an important aspect for law enforcement. With the magnitude of information that can be gathered, investigators can more accurately determine time of death, location, how long a body has been in a specific area, if it has been moved, and other important factors. Blood meal extraction To extract a blood meal from the abdomen of an insect to isolate and analyze DNA, the insect must first be killed by placing it in 96% ethanol. The killed insect can be stored at -20 °C until analysis. When it is time for analysis, the DNA must then be extracted by dissecting the posterior end of the abdomen and collecting 25 mg of tissue. The cut in the abdomen should be made with a razor blade as close to the posterior as possible to avoid the stomach. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Forensic Entomology
Forensic entomology is the scientific study of the colonization of a dead body by arthropods. This includes the study of insect types commonly associated with cadavers, their respective life cycles, their ecological presences in a given environment, as well as the changes in insect assemblage with the progression of decomposition. Insect succession patterns are identified based on the time a given species of insect spends in a given developmental stage, and how many generations have been produced since the insects introduction to a given food source. Insect development alongside environmental data such as temperature and vapor density, can be used to estimate the time since death, due to the fact that flying insects are attracted to a body immediately after death. The identification of postmortem interval to aid in death investigations is the primary scope of this scientific field. However, forensic entomology is not limited to homicides, it has also been used in cases of neglect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Horse-fly
Horse-flies or horseflies are true Fly, flies in the family Tabanidae in the insect Order (biology), order Diptera. They are often large and agile in flight, and only the female horseflies bite animals, including humans, to hematophagy, obtain blood. They prefer to fly in sunlight, avoiding dark and shady areas, and are inactive at night. They are found all over the world except for some islands and the polar regions (Hawaii, Greenland, Iceland). Both horse-flies and Botfly, botflies (Oestridae) are sometimes referred to as gadflies. Adult horse-flies feed on nectar and plant exudates; the males have weak insect mouthparts, mouthparts and only the females bite animals to obtain enough protein from blood to produce eggs. The mouthparts of females are formed into a stout stabbing organ with two pairs of sharp cutting blades, and a spongelike part used to lap up the blood that flows from the wound. The larvae are Predation, predaceous and grow in semiaquatic habitats. Female hor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Body Louse
The body louse (''Pediculus humanus humanus'', also known as ''Pediculus humanus corporis'') is a hematophagic ectoparasite louse that infests humans. It is one of three lice which infest humans, the other two being the head louse, and the crab louse or pubic louse. Despite the name, body lice do not directly live on the host. They lay their eggs on fibres of clothing and only come into contact with the host whenever they need to feed. Since body lice cannot jump or fly, they spread by direct contact with another person or more rarely by contact with clothing or bed sheets that are infested. Body lice are disease vectors and can transmit pathogens that cause human diseases such as epidemic typhus, trench fever, and relapsing fever. In developed countries, infestations are only a problem in areas of poverty where there is poor body hygiene, crowded living conditions, and a lack of access to clean clothing. Outbreaks can also occur in situations where large groups of people a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Head Louse
The head louse (''Pediculus humanus capitis'') is an obligate ectoparasite of humans. Head lice are wingless insects that spend their entire lives on the human scalp and feeding exclusively on human blood. Humans are the only known hosts of this specific parasite, while chimpanzees and bonobos host a closely related species, ''Pediculus schaeffi''. Other species of lice infest most orders of mammals and all orders of birds. Lice differ from other hematophagic ectoparasites such as fleas in spending their entire lifecycle on a host. Head lice cannot fly, and their short, stumpy legs render them incapable of jumping, or even walking efficiently on flat surfaces. The non-disease-carrying head louse differs from the related disease-carrying body louse (''Pediculus humanus humanus'') in preferring to attach eggs to scalp hair rather than to clothing. The two subspecies are morphologically almost identical, but do not normally interbreed. From genetic studies, they are thought to h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lice
Louse ( : lice) is the common name for any member of the clade Phthiraptera, which contains nearly 5,000 species of wingless parasitic insects. Phthiraptera has variously been recognized as an order, infraorder, or a parvorder, as a result of developments in phylogenetic research. Lice are obligate parasites, living externally on warm-blooded hosts which include every species of bird and mammal, except for monotremes, pangolins, and bats. Lice are vectors of diseases such as typhus. Chewing lice live among the hairs or feathers of their host and feed on skin and debris, while sucking lice pierce the host's skin and feed on blood and other secretions. They usually spend their whole life on a single host, cementing their eggs, called nits, to hairs or feathers. The eggs hatch into nymphs, which moult three times before becoming fully grown, a process that takes about four weeks. Genetic evidence indicates that lice are a highly modified lineage of Psocoptera (now called Ps ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reduviidae
The Reduviidae are a large cosmopolitan family of the order Hemiptera (true bugs). Among the Hemiptera and together with the Nabidae almost all species are terrestrial ambush predators: most other predatory Hemiptera are aquatic. The main examples of nonpredatory Reduviidae are some blood-sucking ectoparasites in the subfamily Triatominae. Though spectacular exceptions are known, most members of the family are fairly easily recognizable; they have a relatively narrow neck, sturdy build, and a formidable curved proboscis (sometimes called a rostrum). Large specimens should be handled with caution, if at all, because they sometimes defend themselves with a very painful stab from the proboscis. Taxonomy The Reduviidae are members of the suborder Heteroptera of the order Hemiptera. The family members are almost all predatory, except for a few blood-sucking species, some of which are important as disease vectors. About 7000 species have been described, in more than 20 recognized subfa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Obligate Parasite
An obligate parasite or holoparasite is a parasitic organism that cannot complete its life-cycle without exploiting a suitable host. If an obligate parasite cannot obtain a host it will fail to reproduce. This is opposed to a facultative parasite, which can act as a parasite but does not rely on its host to continue its life-cycle. Obligate parasites have evolved a variety of parasitic strategies to exploit their hosts. Holoparasites and some hemiparasites are obligate. It is advantageous for the parasite to preserve the health of their host when this is compatible with their nutritional and reproductive requirements, except when the death of the host is necessary for transmission.Combes, C. (1997) Fitness of Parasites: Pathology and Selection ''International Journal for Parasitology'' 27 (1): 1–10. Species Obligate parasitism is exhibited in a range of organisms, with examples in viruses, bacteria, fungi, plants, and animals.Balashov, Yu.S. (2011) Parasitism and Ecological Paras ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bed Bug (insect)
''Cimex'' is a genus of insects in the family Cimicidae. ''Cimex'' species are ectoparasites that typically feed on the blood of birds and mammals. Two species, ''Cimex lectularius'' and ''Cimex hemipterus'', are known as bed bugs and frequently feed on humans, although other species may parasitize humans opportunistically. Species that primarily parasitize bats are known as bat bugs. The insects are long and have flattened reddish-brown bodies with small nonfunctional wings. Description Adult ''Cimex'' are light brown to reddish-brown, flat and oval. The mouthparts are beak-like, and adapted for piercing and sucking. Following a blood meal the abdomen is plump and darker in colour. The front wings are vestigial and reduced to pad-like structures and there are no hind wings. ''Cimex'' have segmented abdomens with microscopic hairs that give them a banded appearance. Adults grow to long. The different species are very similar in morphology and can only be separated by micr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rat Flea
A rat flea is a parasite of rats. There are at least four species: * Oriental rat flea (''Xenopsylla cheopis''), also known as the tropical rat flea, the primary vector for bubonic plague * Northern rat flea (''Nosopsyllus fasciatus''). According to Prince, "... it too is an efficient vector of plague. It was found to be even more widely distributed than X. cheopis, occurring in 12 of the 13 States surveyed". * Xenopsylla brasiliensis, a vector of bubonic plague Bubonic plague is one of three types of plague caused by the plague bacterium (''Yersinia pestis''). One to seven days after exposure to the bacteria, flu-like symptoms develop. These symptoms include fever, headaches, and vomiting, as well a ..., found in South America, Africa, and India * Leptopsylla segnis References {{Animal common name Insect common names Former disambiguation pages converted to set index articles ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Flea
The human flea (''Pulex irritans'') – once also called the house flea – is a cosmopolitan flea species that has, in spite of the common name, a wide host spectrum. It is one of six species in the genus ''Pulex''; the other five are all confined to the Nearctic and Neotropical realms. The species is thought to have originated in South America, where its original host may have been the guinea pig or peccary. Morphology and behavior ''Pulex irritans'' is a holometabolous insect with a four-part lifecycle consisting of eggs, larvae, pupae, and adults. Eggs are shed by the female in the environment and hatch into larvae in about 3–4 days. Larvae feed on organic debris in the environment. Larvae eventually form pupae, which are in cocoons that are often covered with debris from the environment (sand, pebbles, etc.). The larval and pupal stages are completed in about 3–4 weeks when the adults hatch from pupae, then must seek out a warm-blooded host for blood meals. The flea egg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Northern Rat Flea
''Nosopsyllus fasciatus'', the northern rat flea, is a species of flea found on domestic rats and house mice. Northern rat fleas are external parasitism, parasites, living by hematophagy off the blood of rodents. ''N. fasciatus'' can bite humans, but they are more common parasites of rodents.Zurita, A., Callejon, R., de Rojas, M. and Cutillas, C.. 2017. Morphological and molecular study of the genus ''Nosopsyllus'' (Siphonaptera: Ceratophyllidae). ''Nosopsyllus barbarus'' (Jordan & Rothschild 1912) as a junior synonym of ''Nosopsyllus fasciatus'' (Bosc d’Antic, 1800). Insect Systematics & Evolution. 49(1): pp.81-101. Since they are associated with humans, they are common disease vectors that can spread from animals to humans. Diseases that can be spread through fleas include the plague and typhus. The rat flea is widespread due to their relationship to rodents and other vertebrates. They can be found co-infecting their host with other parasites. It is the most widely spread of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cat Flea
The cat flea (scientific name ''Ctenocephalides felis'') is an extremely common parasitic insect whose principal host is the domestic cat, although a high proportion of the fleas found on dogs also belong to this species. This is despite the widespread existence of a separate and well-established "dog" flea, ''Ctenocephalides canis''. Cat fleas originated in Africa but can now be found globally. As humans began domesticating cats, the prevalence of the cat flea increased and it spread throughout the world. Of the cat fleas, ''Ctenocephalides felis felis'' is the most common, although other subspecies do exist, including ''C. felis strongylus, C. orientis,'' and ''C. damarensis.'' Over 90% of fleas found on both dogs and cats are ''Ctenocephalides felis felis.'' Overview The cat flea belongs to the insect order Siphonaptera which in its adult stage is an obligatory hematophage. Adults of both sexes range from 1–2 mm long and are usually a reddish-brown colour, although ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
