1.
Waste picker
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A waste picker is a person who salvages reusable or recyclable materials thrown away by others to sell or for personal consumption. There are millions of waste pickers worldwide, predominantly in developing countries, forms of waste picking have been practiced since antiquity, but modern traditions of waste picking took root during industrialization in the nineteenth century. Over the past half-century, waste picking has expanded vastly in the world due to urbanization, toxic colonialism. Many cities only provide solid waste collection, Many terms are used to refer to people who salvage recyclables from the waste stream for sale or personal consumption. A more contemporary term, focusing on the outcome of the activity, is informal sector recycling. However, the word informal can be misleading, because in practice a continuum between total informality and proper organization in taxed registered formal activities may be encountered. In 2008, participants of the The First World Conference of Waste Pickers chose to use the waste picker for English usage to facilitate global communication. The term “scavenger” is also used, but many waste pickers find it demeaning due to the implied comparison with animals. A waste picker is different from a waste collector because the waste collected by the latter may be destined for a landfill or incinerator, not necessarily for a recycling facility. Dumpster diving generally refers to the practice of anti-consumer and freegan activists who reclaim items such as food, “Waste picking” generally refers to activity motivated purely by economic need. There is little data about the number and demographics of waste pickers worldwide. Most academic research on waste pickers is qualitative rather than quantitative, systematic large-scale data collection is difficult due to the profession’s informal nature, porous borders, seasonally fluctuating workforce, and widely dispersed and mobile worksites. Also, many researchers are reluctant to produce quantitative data out of fear that it might be used to justify crackdowns on waste picking by authorities, thus, the large-scale estimates that do exist are mainly extrapolations based on very small original research samples. In his book, The Worlds Scavengers, Martin Medina provides a guide to researching waste picking. In 1988, the World Bank estimated that 1–2% of the population subsists by waste picking. A2010 study estimates there are 1.5 million waste pickers in India alone. Brazil, the country that collects the most robust official statistics on waste pickers, Waste picker incomes vary vastly by location, form of work, and gender. Some waste pickers live in poverty, but many others earn multiple times their country’s minimum wage
2.
Flesh fly
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Flies in the family Sarcophagidae are commonly known as flesh flies. Some flesh fly larvae are parasites of other insects such as Orthoptera. Members of the subfamily Sarcophaginae are small to large flies 0. 16-0.9 in with black and gray stripes on the thorax. Other key features include red eyes and a bristled abdomen, abdominal sternites II and III are free and cover the margins of tergites. The posthumeral bristles are one or two in number, with the outermost pair missing, the presutural bristle is located lower than the notopleural bristle, and closer to the notopleural bristle than to the outermost posthumeral bristle. The presutural bristle is located higher than or level with the posthumeral bristle, the hindmost posthumeral bristle is located even with or toward the midline from the presutural bristle. Four notopleural bristles are present and arranged in the order - short, long, short, vein M1 +2 is always present, and the cubitulus is strongly bent at right angles or acute, vein Rs is dibranched. The eyes are smooth and very rarely hairy, the arista is plumose in its basal half, or rarely pubescent or glabrous. The family contains three subfamilies, the Miltogramminae, the Paramacronychiinae, and the Sarcophaginae, containing between them 108 genera, about 2500 species are in this family. Sarcophaginae, The majority of species in the large genus Sarcophaga are scavengers of carrion, such as dead insects. A few species feed on vertebrate carcasses. Flesh fly maggots occasionally eat other larvae, although this is usually because the larvae are smaller. Flesh flies and their larvae are known to eat decaying vegetable matter and excrement. Miltogramminae, Members of this subfamily are kleptoparasites of solitary bees, Paramacronychiinae, This subfamily includes lepidopteran predators or parasitoids, predators on immatures of bumblebees and generalist scavengers and insect predators. Vairo, Mello-Patiu and Carvalho give an overview of the role of Sarcophagidae in medicolegal entomology. Flesh flies can carry leprosy bacilli and can transmit intestinal pseudomyiasis to people who eat their larvae, Flesh flies, particularly Wohlfahrtia magnifica, can also cause myiasis in animals, mostly to sheep, and can give them blood poisoning, or asymptomatic leprosy infections. Generally, only males of this family can reliably be identified to species, the literature is incomplete or scattered for all regions. Family Sarcophagidae in Stone, A. et al, a catalog of the Diptera of America north of Mexico United States Department of Agriculture, Washington, D. C.1965
3.
Carnivore
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Animals that depend solely on animal flesh for their nutrient requirements are called obligate carnivores while those that also consume non-animal food are called facultative carnivores. A carnivore that sits at the top of the chain is termed an apex predator. Plants that capture and digest insects are called carnivorous plants, similarly, fungi that capture microscopic animals are often called carnivorous fungi. The word carnivore sometimes refers to the mammalian order Carnivora, while many Carnivora meet the definition of being meat eaters, not all do, and even fewer are true obligate carnivores. In addition, there are plenty of species that are not members of Carnivora. Outside the animal kingdom, there are several genera containing carnivorous plants, the former are predominantly insectivores, while the latter prey mostly on microscopic invertebrates, such as nematodes, amoebae and springtails. Carnivores are sometimes characterized by the type of prey that they consume, for example, animals that eat insects and similar invertebrates primarily or exclusively are called insectivores, while those that eat fish primarily or exclusively are called piscivores. The first tetrapods, or land-dwelling vertebrates, were piscivorous amphibians known as labyrinthodonts and they gave rise to insectivorous vertebrates and, later, to predators of other tetrapods. Carnivores may alternatively be classified according to the percentage of meat in their diet, obligate carnivores or true carnivores depend on the nutrients found only in animal flesh for their survival. For instance, felids including the cat are obligate carnivores requiring a diet of primarily animal flesh. Characteristics commonly associated with carnivores include organs for capturing and disarticulating prey, in truth, these assumptions may be misleading, as some carnivores do not hunt and are scavengers. Thus they do not have the associated with hunting carnivores. Carnivores have comparatively short digestive systems, as they are not required to break down tough cellulose found in plants, many animals that hunt other animals have evolved eyes that face forward, thus making depth perception possible. This is almost universal among mammalian predators, other predators, like crocodiles, as well as most reptiles and amphibians, have sideways facing eyes and hunt by ambush rather than pursuit. The first vertebrate carnivores were fish, and then amphibians that moved on to land, early tetrapods were large amphibious piscivores. Some scientists assert that Dimetrodon was the first terrestrial vertebrate to develop the curved, serrated teeth that enable a predator to eat prey much larger than itself. While amphibians continued to feed on fish and later insects, reptiles began exploring two new types, tetrapods, and later, plants. Carnivory was a transition from insectivory for medium and large tetrapods
4.
Herbivore
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A herbivore is an animal anatomically and physiologically adapted to eating plant material, for example foliage, for the main component of its diet. As a result of their plant diet, herbivorous animals typically have mouthparts adapted to rasping or grinding, horses and other herbivores have wide flat teeth that are adapted to grinding grass, tree bark, and other tough plant material. A large percentage of herbivores have mutualistic gut flora that help them digest plant matter and this gut flora is made up of cellulose-digesting protozoans or bacteria living in the herbivores intestines. Herbivore is the form of a modern Latin coinage, herbivora. Richard Owen employed the term in an 1854 work on fossil teeth. Herbivora is derived from the Latin herba meaning a small plant or herb, Herbivory is a form of consumption in which an organism principally eats autotrophs such as plants, algae and photosynthesizing bacteria. More generally, organisms feed on autotrophs in general are known as primary consumers. Herbivory usually refers to eating plants, fungi, bacteria and protists that feed on living plants are usually termed plant pathogens. Flowering plants that obtain nutrition from other living plants are usually termed parasitic plants, there is however no single exclusive and definitive ecological classification of consumption patterns, each textbook has its own variations on the theme. Insects fed on the spores of early Devonian plants, and the Rhynie chert also provides evidence that organisms fed on plants using a pierce, during the next 75 million years, plants evolved a range of more complex organs, such as roots and seeds. There is no evidence of any organism being fed upon until the middle-late Mississippian,330.9 million years ago, further than their arthropod status, the identity of these early herbivores is uncertain. Hole feeding and skeletonisation are recorded in the early Permian, with surface fluid feeding evolving by the end of that period, Herbivory among four-limbed terrestrial vertebrates, the tetrapods developed in the Late Carboniferous. Early tetrapods were large amphibious piscivores, while amphibians continued to feed on fish and insects, some reptiles began exploring two new food types, tetrapods and plants. The entire dinosaur order ornithischia was composed with herbivores dinosaurs, carnivory was a natural transition from insectivory for medium and large tetrapods, requiring minimal adaptation. In contrast, a set of adaptations was necessary for feeding on highly fibrous plant materials. Arthropods evolved herbivory in four phases, changing their approach to it in response to changing plant communities, tetrapod herbivores made their first appearance in the fossil record of their jaws near the Permio-Carboniferous boundary, approximately 300 million years ago. The earliest evidence of their herbivory has been attributed to dental occlusion, the evolution of dental occlusion led to a drastic increase in plant food processing and provides evidence about feeding strategies based on tooth wear patterns. Examination of phylogenetic frameworks of tooth and jaw morphologes has revealed that dental occlusion developed independently in several lineages tetrapod herbivores and this suggests that evolution and spread occurred simultaneously within various lineages
5.
Ecosystem
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An ecosystem is a community of living organisms in conjunction with the nonliving components of their environment, interacting as a system. These biotic and abiotic components are regarded as linked together through nutrient cycles, as ecosystems are defined by the network of interactions among organisms, and between organisms and their environment, they can be of any size but usually encompass specific, limited spaces. Energy, water, nitrogen and soil minerals are other essential components of an ecosystem. The energy that flows through ecosystems is obtained primarily from the sun and it generally enters the system through photosynthesis, a process that also captures carbon from the atmosphere. By feeding on plants and on one another, animals play an important role in the movement of matter and they also influence the quantity of plant and microbial biomass present. Ecosystems are controlled both by external and internal factors, other external factors include time and potential biota. Ecosystems are dynamic entities—invariably, they are subject to disturbances and are in the process of recovering from some past disturbance. Ecosystems in similar environments that are located in different parts of the world can have different characteristics simply because they contain different species. The introduction of species can cause substantial shifts in ecosystem function. Internal factors not only control ecosystem processes but are controlled by them and are often subject to feedback loops. Other internal factors include disturbance, succession and the types of species present, although humans exist and operate within ecosystems, their cumulative effects are large enough to influence external factors like climate. Biodiversity affects ecosystem function, as do the processes of disturbance, classifying ecosystems into ecologically homogeneous units is an important step towards effective ecosystem management, but there is no single, agreed-upon way to do this. The term ecosystem was first used in 1935 in a publication by British ecologist Arthur Tansley, Tansley devised the concept to draw attention to the importance of transfers of materials between organisms and their environment. He later refined the term, describing it as The whole system, including not only the organism-complex, but also the whole complex of physical factors forming what we call the environment. Tansley regarded ecosystems not simply as natural units, but as mental isolates, Tansley later defined the spatial extent of ecosystems using the term ecotope. G. Raymond Lindeman took these ideas one step further to suggest that the flow of energy through a lake was the driver of the ecosystem. Most mineral nutrients, on the hand, are recycled within ecosystems. Ecosystems are controlled both by external and internal factors, external factors, also called state factors, control the overall structure of an ecosystem and the way things work within it, but are not themselves influenced by the ecosystem
6.
Decomposer
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Decomposers are organisms that break down dead or decaying organisms, and in doing so, they carry out the natural process of decomposition. Like herbivores and predators, decomposers are heterotrophic, meaning that they use organic substrates to get their energy, carbon and nutrients for growth and development. Thus, invertebrates such as earthworms, woodlice, and sea cucumbers are technically detritivores, not decomposers, the primary decomposers of litter in many ecosystems are fungi. Unlike bacteria, which are unicellular organisms, most saprotrophic fungi grow as a network of hyphae. While bacteria are restricted to growing and feeding on the surfaces of organic matter. Additionally, only wood-decay fungi have evolved the enzymes necessary to decompose lignin and these two factors make fungi the primary decomposers in forests, where litter has high concentrations of lignin and often occurs in large pieces. Fungi decompose organic matter by releasing enzymes to break down the decaying material, hyphae used to break down matter and absorb nutrients are also used in reproduction. When two compatible fungis hyphae grow close to other, they will then fuse together for reproduction
7.
Detritivore
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Detritivores, also known as detrivores, detritophages, detritus feeders, or detritus eaters, are heterotrophs that obtain nutrients by consuming detritus. There are many kinds of invertebrates, vertebrates and plants carry out coprophagy. By doing so, all these detritivores contribute to decomposition and the nutrient cycles, however, the terms detritivore and decomposer are often used interchangeably. Detritivores are an important aspect of many ecosystems and they can live on any soil with an organic component, including marine ecosystems, where they are termed interchangeably with bottom feeders. The eating of wood, whether alive or dead, is known as xylophagy, Τhe activity of animals feeding only on dead wood is called sapro-xylophagy and those animals, sapro-xylophagous. In food webs, detritivores generally play the roles of decomposers, detritivores are often eaten by consumers and therefore commonly play important roles as recyclers in ecosystem energy flow and biogeochemical cycles. Many detritivores live in woodland, though the term can be applied to certain bottom-feeders in wet environments. These organisms play a role in benthic ecosystems, forming essential food chains. Fungi, acting as decomposers, are important in todays terrestrial environment, by feeding on sediments directly to extract the organic component, some detritivores accidentally concentrate toxic pollutants. Decomposer Saprotrophic nutrition Nepenthes ampullaria Consumer-resource systems
8.
Customs
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The movement of people into and out of a country is normally monitored by immigration authorities, under a variety of names and arrangements. Each country has its own laws and regulations for the import and export of goods into and out of a country, the import or export of some goods may be restricted or forbidden. In most countries, customs are attained through government agreements and international laws, a customs duty is a tariff or tax on the importation or exportation of goods. Commercial goods not yet cleared through customs are held in an area, often called a bonded store. All authorized ports are recognized customs areas, at airports, customs is the point of no return for all passengers, once a passenger has cleared customs, they cannot go back. In many countries, customs procedures for arriving passengers at many international airports and some road crossings are separated into red, passengers with goods to declare go through the red channel. Passengers with nothing to go through the green channel. Each channel is a point of no return, once a passenger has entered a particular channel, australia, Canada, New Zealand, and the United States do not officially operate a red and green channel system, however, some airports copy this layout. Airports in EU countries such as Finland, Ireland or the United Kingdom, as the EU is a customs union, travellers between EU countries do not have to pay customs duties. Value-added tax and excise duties may be if the goods are subsequently sold. Passengers arriving from other EU countries go through the blue channel, luggage tickets for checked luggage travelling within the EU are green-edged so they may be identified. In most EU member states, travellers coming from other EU countries can use the green lane. All airports in the United Kingdom operate a system, however some dont have a red channel. Customs is part of one of the three functions of a government, namely, administration, maintenance of law, order, and justice. However, in a bid to mitigate corruption, many countries have partly privatised their customs and this has occurred by way of contracting pre-shipment inspection agencies, which examine the cargo and verify the declared value before importation occurs. The countrys customs is obliged to accept the report for the purpose of assessing duties and taxes at the port of entry. It has been found that evasion of customs duty escalated when pre-shipment agencies took over and it has also been alleged that involvement of such agencies has caused shipping delays. Privatization of customs has been viewed as a fatal remedy, the basic customs law is harmonized across Europe within the European Union Customs Union
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