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Simplified schematic of an island's fauna - all its animal species, highlighted in boxes Fauna.png
Simplified schematic of an island's fauna – all its animal species, highlighted in boxes

Fauna is all of the animal life present in a particular region or time. The corresponding term for plants is flora . Flora, fauna and other forms of life such as fungi are collectively referred to as biota . Zoologists and paleontologists use fauna to refer to a typical collection of animals found in a specific time or place, e.g. the "Sonoran Desert fauna" or the "Burgess Shale fauna". Paleontologists sometimes refer to a sequence of faunal stages, which is a series of rocks all containing similar fossils. The study of animals of a particular region is called faunistics.



Fauna comes from the name Fauna, a Roman goddess of earth and fertility, the Roman god Faunus, and the related forest spirits called Fauns. All three words are cognates of the name of the Greek god Pan, and panis is the Greek equivalent of fauna. Fauna is also the word for a book that catalogues the animals in such a manner. The term was first used by Carl Linnaeus from Sweden in the title of his 1745 [1] work Fauna Suecica

Subdivisions on the basis of region


Cryofauna refers to the animals that live in, or very close to, cold areas.


Cryptofauna are the fauna that exist in protected or concealed microhabitats. [2]


This time-lapse movie shows images taken every hour during a two-week period. Worms, bacteria and fish are shown disturbing the sediment as they burrow and move through it.

Infauna are benthic organisms that live within the bottom substratum of a water body, especially within the bottom-most oceanic sediments, the layer of small particles at the bottom of a body of water, rather than on its surface. Bacteria and microalgae may also live in the interstices of bottom sediments. In general, infaunal animals become progressively smaller and less abundant with increasing water depth and distance from shore, whereas bacteria show more constancy in abundance, tending toward one million cells per milliliter of interstitial seawater..

Such creatures are found in the fossil record and include lingulata, trilobites and worms. They made burrows in the sediment as protection and may also have fed upon detritus or the mat of microbes which tended to grow on the surface of the sediment. [3] Today, a variety of organisms live in and disturb the sediment. The deepest burrowers are the ghost shrimps ( Thalassinidea ), which go as deep as 3 metres (10 ft) into the sediment at the bottom of the ocean. [4]


Epifauna, also called epibenthos, are aquatic animals that live on the bottom substratum as opposed to within it, that is, the benthic fauna that live on top of the sediment surface at the seafloor.


Macrofauna are benthic or soil organisms which are retained on a 0.5 mm sieve. Studies in the deep sea define macrofauna as animals retained on a 0.3 mm sieve to account for the small size of many of the taxa.


Australian and New Zealand fauna. This image was likely first published in the first edition (1876-1899) of the Nordisk familjebok. Australisk fauna, Nordisk familjebok.jpg
Australian and New Zealand fauna. This image was likely first published in the first edition (1876–1899) of the Nordisk familjebok .

Megafauna are large animals of any particular region or time. For example, Australian megafauna.


Meiofauna are small benthic invertebrates that live in both marine and freshwater environments. The term meiofauna loosely defines a group of organisms by their size, larger than microfauna but smaller than macrofauna, rather than a taxonomic grouping. One environment for meiofauna is between grains of damp sand (see Mystacocarida).

In practice these are metazoan animals that can pass unharmed through a 0.5 1 mm mesh but will be retained by a 30–45 μm mesh, [5] but the exact dimensions will vary from researcher to researcher. Whether an organism passes through a 1 mm mesh also depends upon whether it is alive or dead at the time of sorting.


Mesofauna are macroscopic soil animals such as arthropods or nematodes. Mesofauna are extremely diverse; considering just the springtails (Collembola), as of 1998, approximately 6,500 species had been identified. [6]


Microfauna are microscopic or very small animals (usually including protozoans and very small animals such as rotifers).


Theoretically, Xenofauna are alien organisms that can be described as animal analogues. As of the current day, no alien life forms, animal or otherwise, are known to exist. Despite this, the idea of alien life remains a popular subject of interest in the fields of astronomy, astrobiology, biochemistry, evolutionary biology, science fiction, and philosophy.


Examples of fauna in Olleros de Tera (Spain) Fauna.jpg
Examples of fauna in Olleros de Tera (Spain)

Other terms include avifauna , which means "bird fauna" and piscifauna (or ichthyofauna ), which means "fish fauna".


Classic faunas

See also

Related Research Articles


Benthos, from the Greek benthos meaning "depth of the sea", is the community of organisms that live on, in, or near the seabed, river, lake, or stream bottom, also known as the benthic zone. This community lives in or near marine or freshwater sedimentary environments, from tidal pools along the foreshore, out to the continental shelf, and then down to the abyssal depths.

Meiobenthos, also called meiofauna, are small benthic invertebrates that live in both marine and fresh water environments. The term meiofauna loosely defines a group of organisms by their size, larger than microfauna but smaller than macrofauna, rather than a taxonomic grouping. In practice, that is organisms that can pass through a 1 mm mesh but will be retained by a 45 μm mesh, but the exact dimensions will vary from researcher to researcher. Whether an organism will pass through a 1 mm mesh will also depend upon whether it is alive or dead at the time of sorting.

Cold seep Ocean floor area where hydrogen sulfide, methane and other hydrocarbon-rich fluid seepage occurs

A cold seep is an area of the ocean floor where hydrogen sulfide, methane and other hydrocarbon-rich fluid seepage occurs, often in the form of a brine pool. Cold does not mean that the temperature of the seepage is lower than that of the surrounding sea water. On the contrary, its temperature is often slightly higher. The "cold" is relative to the very warm conditions of a hydrothermal vent. Cold seeps constitute a biome supporting several endemic species.


Detritivores are heterotrophs that obtain nutrients by consuming detritus. There are many kinds of invertebrates, vertebrates and plants that carry out coprophagy. By doing so, all these detritivores contribute to decomposition and the nutrient cycles. They should be distinguished from other decomposers, such as many species of bacteria, fungi and protists, which are unable to ingest discrete lumps of matter, but instead live by absorbing and metabolizing on a molecular scale. However, the terms detritivore and decomposer are often used interchangeably.

Benthic zone the region at the lowest level of a body of water including the sediment surface and some sub-surface layers

The benthic zone is the ecological region at the lowest level of a body of water such as an ocean, lake, or stream, including the sediment surface and some sub-surface layers. Organisms living in this zone are called benthos and include microorganisms as well as larger invertebrates, such as crustaceans and polychaetes. Organisms here generally live in close relationship with the substrate and many are permanently attached to the bottom. The benthic boundary layer, which includes the bottom layer of water and the uppermost layer of sediment directly influenced by the overlying water, is an integral part of the benthic zone, as it greatly influences the biological activity that takes place there. Examples of contact soil layers include sand bottoms, rocky outcrops, coral, and bay mud.

Bioturbation reworking of soils and sediments by organisms.

Bioturbation is defined as the reworking of soils and sediments by animals or plants. These include burrowing, ingestion, and defecation of sediment grains. Bioturbating activities have a profound effect on the environment and are thought to be a primary driver of biodiversity. The formal study of bioturbation began in the 1800s by Charles Darwin experimenting in his garden. The disruption of aquatic sediments and terrestrial soils through bioturbating activities provides significant ecosystem services. These include the alteration of nutrients in aquatic sediment and overlying water, shelter to other species in the form of burrows in terrestrial and water ecosystems, and soil production on land.

Habitat The type of environment in which an organism lives

In ecology, habitat identifies as the array of resources, physical and biotic factors, present in an area that allow the survival and reproduction of a particular species. A species habitat can be seen as the physical manifestation of its ecological niche. Thus, habitat is a species-specific term, fundamentally different from concepts such as environment or vegetation assemblages, for which the term habitat-type is more appropriate.

Aquatic ecosystem ecosystem in a body of water

An aquatic ecosystem is an ecosystem in a body of water. Communities of organisms that are dependent on each other and on their environment live in aquatic ecosystems. The two main types of aquatic ecosystems are marine ecosystems and freshwater ecosystems.

Native plant Plant indigenous to a given area in geologic time

Native plants are plants indigenous to a given area in geologic time. This includes plants that have developed, occur naturally, or existed for many years in an area.

The profundal zone is a deep zone of an inland body of freestanding water, such as a lake or pond, located below the range of effective light penetration. This is typically below the thermocline, the vertical zone in the water through which temperature drops rapidly. The temperature difference may be large enough to hamper mixing with the littoral zone in some seasons which causes a decrease in oxygen concentrations. The profundal is often defined, as the deepest, vegetation-free, and muddy zone of the lacustrine benthal. The profundal zone is often part of the aphotic zone. Sediment in the profundal zone primarily comprises silt and mud.

A lake ecosystem or lacustrine ecosystem includes biotic (living) plants, animals and micro-organisms, as well as abiotic (non-living) physical and chemical interactions. Lake ecosystems are a prime example of lentic ecosystems, which include ponds, lakes and wetlands, and much of this article applies to lentic ecosystems in general. Lentic ecosystems can be compared with lotic ecosystems, which involve flowing terrestrial waters such as rivers and streams. Together, these two fields form the more general study area of freshwater or aquatic ecology.

Soil biology

Soil biology is the study of microbial and faunal activity and ecology in soil. Soil life, soil biota, soil fauna, or edaphon is a collective term that encompasses all organisms that spend a significant portion of their life cycle within a soil profile, or at the soil-litter interface. These organisms include earthworms, nematodes, protozoa, fungi, bacteria, different arthropods, as well as some reptiles, and species of burrowing mammals like gophers, moles and prairie dogs. Soil biology plays a vital role in determining many soil characteristics. The decomposition of organic matter by soil organisms has an immense influence on soil fertility, plant growth, soil structure, and carbon storage. As a relatively new science, much remains unknown about soil biology and its effect on soil ecosystems.


Microfauna refers to microscopic organisms that exhibit animal-like qualities. Microfauna are represented in the animal kingdom and the protist kingdom. This is in contrast to microflora which, together with microfauna, make up the microzoa.

Sediment Profile Imagery (SPI) is an underwater technique for photographing the interface between the seabed and the overlying water. The technique is used to measure or estimate biological, chemical, and physical processes occurring in the first few centimetres of sediment, pore water, and the important benthic boundary layer of water. Time-lapse imaging (tSPI) is used to examine biological activity over natural cycles, like tides and daylight or anthropogenic variables like feeding loads in aquaculture. SPI systems cost between tens and hundreds of thousands of dollars and weigh between 20 and 400 kilograms. Traditional SPI units can be effectively used to explore continental shelf and abyssal depths. Recently developed SPI-Scan or rSPI systems can now also be used to inexpensively investigate shallow (<50m) freshwater, estuarine, and marine systems.

Arctic sea ice ecology and history

The Arctic sea ice covers less area in the summer than in the winter. The multi-year sea ice covers nearly all of the central deep basins. The Arctic sea ice and its related biota are unique, and the year-round persistence of the ice has allowed the development of ice endemic species, meaning species not found anywhere else.

The mangroves of the Straits of Malacca are found along the coast of Thailand, Malaysia, Singapore and northern Sumatra. These tropical mangrove forests are highly diverse, and are important wetlands with high conservation values. There are two Ramsar sites along the Strait of Malacca: Pulau Kukup and Tanjung Piai.

Marine habitats A habitat that supports marine life

Marine habitats are habitats that support marine life. Marine life depends in some way on the saltwater that is in the sea. A habitat is an ecological or environmental area inhabited by one or more living species. The marine environment supports many kinds of these habitats.

Epibenthic sled An instrument designed to collect benthic and benthopelagic faunas from the deep sea

An Epibenthic sled is an instrument designed to collect benthic and benthopelagic faunas from the deep sea. The sled is made from a steel frame consisting of two skids and stabilizing planes to keep it from sinking too deep into the mud. Attached to the frame is a 1 mm mesh net to collect the samples. The sled is towed along the seafloor at the sediment water interface. The device has a mechanically operated door that is closed when the sled is mid water and opens when it reaches the seafloor. When the fauna is collected, the door closes again to preserve the sample on the long trek back through the water column. The door prevents washing of the sample and loss of organisms through turbulence generated as the net is lifted out. The epibenthic sled can also be used with external sensors and cameras.

Helderberg Marine Protected Area A marine conservation area in the Western Cape in South Africa

The Helderberg Marine Protected Area is a small marine conservation area on the north-eastern side of False Bay in the Western Cape province of South Africa, It lies between the mouths of the Lourens River in the Strand, and the Eerste River in Macassar.

Benthic-pelagic coupling are processes that connect the benthic zone and the pelagic zone through the exchange of energy, mass, or nutrients. These processes play a prominent role in both freshwater and marine ecosystems and are influenced by a number of chemical, biological, and physical forces that are crucial to functions from nutrient cycling to energy transfer in food webs.


  1. Wikisource:1911 Encyclopædia Britannica/Linnaeus
  2. NCRI
  3. Vermeij, Geerat (2009), Nature: An Economic History, Princeton University Press, ISBN   9781400826490 . p. 266
  4. Vermeij, Geerat (2009), Nature: An Economic History, Princeton University Press, ISBN   9781400826490 . p. 267
  5. Fauna of Sandy Beaches
  6. Josef Rusek (1998). "Biodiversity of Collembola and their functional role in the ecosystem". Biodiversity and Conservation. 7 (9): 1207–1219. doi:10.1023/A:1008887817883. S2CID   22883809.