Consumer–resource interactions are the core motif of ecological

food chains ''Food Chains'' is a 2014 American documentary film about agricultural labor in the United States directed by Sanjay Rawal. It was the Recipient of the 2015 James Beard Foundation Award for Special/Documentary.James Beard Foundation/ The 2015 Book, ...

or food webs, and are an umbrella term for a variety of more specialized types of biological species interactions including prey-predator (see

predation Predation is a biological interaction in which one organism, the predator, kills and eats another organism, its prey. It is one of a family of common List of feeding behaviours, feeding behaviours that includes parasitism and micropredation ...

), host-parasite (see

parasitism Parasitism is a close relationship between species, where one organism, the parasite, lives (at least some of the time) on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The en ...

), plant-

herbivore A herbivore is an animal anatomically and physiologically evolved to feed on plants, especially upon vascular tissues such as foliage, fruits or seeds, as the main component of its diet. These more broadly also encompass animals that eat ...

and victim-exploiter systems. These kinds of interactions have been studied and modeled by population ecologists for nearly a century. Species at the bottom of the food chain, such as

algae Algae ( , ; : alga ) is an informal term for any organisms of a large and diverse group of photosynthesis, photosynthetic organisms that are not plants, and includes species from multiple distinct clades. Such organisms range from unicellular ...

and other

autotrophs An autotroph is an organism that can convert abiotic sources of energy into energy stored in organic compounds, which can be used by other organisms. Autotrophs produce complex organic compounds (such as carbohydrates, fats, and proteins) us ...

, consume non-biological resources, such as

minerals In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid substance with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form.John P. Rafferty, ed. (2011): M ...

and

nutrients A nutrient is a substance used by an organism to survive, grow and reproduce. The requirement for dietary nutrient intake applies to animals, plants, fungi and protists. Nutrients can be incorporated into cells for metabolic purposes or excret ...

of various kinds, and they derive their energy from light (

photons A photon () is an elementary particle that is a quantum of the electromagnetic field, including electromagnetic radiation such as light and radio waves, and the force carrier for the electromagnetic force. Photons are massless particles that ...

) or chemical sources. Species higher up in the food chain survive by consuming other species and can be classified by what they eat and how they obtain or find their food.

Classification of consumer types

The standard categorization

Various terms have arisen to define consumers by what they eat, such as meat-eating

carnivore A carnivore , or meat-eater (Latin, ''caro'', genitive ''carnis'', meaning meat or "flesh" and ''vorare'' meaning "to devour"), is an animal or plant Plants are the eukaryotes that form the Kingdom (biology), kingdom Plantae; they ar ...

s, fish-eating

piscivore A piscivore () is a carnivorous animal that primarily eats fish. Fish were the diet of early tetrapod evolution (via water-bound amphibians during the Devonian period); insectivory came next; then in time, the more terrestrially adapted repti ...

s, insect-eating

insectivore file:Common brown robberfly with prey.jpg, A Asilidae, robber fly eating a hoverfly An insectivore is a carnivore, carnivorous animal or plant which eats insects. An alternative term is entomophage, which can also refer to the Entomophagy ...

s, plant-eating

s, seed-eating granivores, and fruit-eating

frugivores A frugivore ( ) is an animal that thrives mostly on raw fruits or succulent fruit-like produce of plants such as roots, shoots, nuts and seeds. Approximately 20% of mammalian herbivores eat fruit. Frugivores are highly dependent on the abundance ...

and omnivores are meat eaters and plant eaters. An extensive classification of consumer categories based on a list of feeding behaviors exists.

The Getz categorization

Another way of categorizing consumers, proposed by South African American ecologist Wayne Getz, is based on a biomass transformation web (BTW) formulation that organizes resources into five components: live and dead animal, live and dead plant, and particulate matter (such like composted carcass; rotting plant matter). It also distinguishes between consumers that gather their resources by moving across landscapes from those that mine their resources by becoming sessile once they have located a stock of resources large enough for them to feed on during completion of a full life history stage. In Getz's scheme, words for miners are of Greek etymology and words for gatherers are of Latin etymology. Thus a bestivore, such as a cat, preys on live animals (Latin: bestia=animal) while a sarcophage, such as a

botfly Botflies, also known as warble flies, heel flies, and gadflies, are flies of the family Oestridae. Their larvae are internal parasites of mammals, some species growing in the host's flesh and others within the gut. '' Dermatobia hominis'' is ...

larva mines live flesh and a zontanophage (Greek: zontanos=alive), such as a leaf miner, mines live plant material. A carcasivore (Latin: carcasium=carcass), such as white-backed vulture, scavenge animal carcasses while a necrophage (Greek: nekros=dead body), such as a blowfly, mines dead flesh. Victivores (Latin: victus=living) gather live plant material and thus include frugivores, nectivores, graminivores, granivores and folivores as subcategories. Lectivores, such as many termites, gather dead plant material (Latin: lectus=bed which is the root of the word litter, as in leaf-litter) and thanatophages (Greek: thanatos=death), such as pillbugs mine piles of dead plant material. Carnivore and herbivore are generic multigroup categories for gathers respectively of animal and plant material, irrespective of whether live or dead. Croppers, scavengers, and detritivores are gatherers respectively of live, dead, and particulate material. Parasites, saprophages, and decomposers are miners respectively of live, dead, and particulate material.

Specialist totivores (gatherers)

Folivore In zoology, a folivore is a herbivore that specializes in eating leaves. Mature leaves contain a high proportion of hard-to-digest cellulose, less energy than other types of foods, and often toxic compounds.Jones, S., Martin, R., & Pilbeam, D. (1 ...

Frugivore A frugivore ( ) is an animal that thrives mostly on raw fruits or succulent fruit-like produce of plants such as roots, shoots, nuts and seeds. Approximately 20% of mammalian herbivores eat fruit. Frugivores are highly dependent on the abundance ...

Fungivore Fungivory or mycophagy is the process of organisms consuming fungi. Many different organisms have been recorded to gain their energy from consuming fungi, including birds, mammals, insects, plants, amoebas, gastropods, nematodes, bacteria and othe ...

Carnivore A carnivore , or meat-eater (Latin, ''caro'', genitive ''carnis'', meaning meat or "flesh" and ''vorare'' meaning "to devour"), is an animal or plant Plants are the eukaryotes that form the Kingdom (biology), kingdom Plantae; they ar ...

Insectivore file:Common brown robberfly with prey.jpg, A Asilidae, robber fly eating a hoverfly An insectivore is a carnivore, carnivorous animal or plant which eats insects. An alternative term is entomophage, which can also refer to the Entomophagy ...

* Molluscivore *

Piscivore A piscivore () is a carnivorous animal that primarily eats fish. Fish were the diet of early tetrapod evolution (via water-bound amphibians during the Devonian period); insectivory came next; then in time, the more terrestrially adapted repti ...

* Avivore *

Spongivore A spongivore is an animal anatomically and physiologically adapted to eating animals of the phylum Porifera, commonly called sea sponges, for the main component of its diet. As a result of their diet, spongivore animals like the hawksbill turtle h ...

* Graminivore * Granivore *

Nectarivore In zoology, a nectarivore is an animal which derives its energy and nutrient requirements from a diet consisting mainly or exclusively of the sugar-rich nectar produced by flowering plants. Nectar as a food source presents a number of benefits ...

Palynivore In zoology, a palynivore /pəˈlɪnəvɔːɹ/, meaning "pollen eater" (from Greek παλύνω palunō, "strew, sprinkle", and Latin, vorare, meaning "to devour") is an herbivorous animal which selectively eats the nutrient-rich pollen produced b ...

Bacterivore A bacterivore is an organism which obtains energy and nutrients primarily or entirely from the consumption of bacteria. The term is most commonly used to describe free-living, heterotrophic, microscopic organisms such as nematodes as well as many s ...

Detritivore Detritivores (also known as detrivores, detritophages, detritus feeders or detritus eaters) are heterotrophs that obtain nutrients by consuming detritus (decomposing plant and animal parts as well as feces). There are many kinds of invertebrates, ...

* Ophiophagy

Specialist olophages (miners)

Coprophagy Coprophagia ( ) or coprophagy ( ) is the consumption of feces. The word is derived from the Ancient Greek "feces" and "to eat". Coprophagy refers to many kinds of feces-eating, including eating feces of other species (heterospecifics), of o ...

Geophagy Geophagia (), also known as geophagy (), is the intentional practice of consuming earth or soil-like substances such as clay, chalk, or termite mounds. It is a behavioural adaptation that occurs in many non-human animals and has been documented i ...

Hematophagy Hematophagy (sometimes spelled haematophagy or hematophagia) is the practice by certain animals of feeding on blood (from the Greek words αἷμα ' "blood" and φαγεῖν ' "to eat"). Since blood is a fluid tissue rich in nutritious ...

* Lepidophagy * Mucophagy * Myrmecophagy * Osteophagy *

Oophagy Oophagy ( ) or ovophagy, literally "egg eating", is the practice of embryos feeding on eggs produced by the ovary while still inside the mother's uterus. The word oophagy is formed from the classical Greek (, "egg") and classical Greek (, "to ...

* Ophiophagy * Ovophagy * Placentophagy * Saprophagy * Sarcophagy * Thanatophagy * Xylophagy * Zontanophagy

References