Genus ( / ˈ dʒ iː n ə s / ; pl. : genera / ˈ dʒ ɛ n ər ə / ) is a taxonomic rank above species and below family as used in the biological classification of living and fossil organisms as well as viruses . In binomial nomenclature , the genus name forms the first part of the binomial species name for each species within the genus.
87-667: See text Saxifraga is the largest genus in the family Saxifragaceae , containing about 473 species of holarctic perennial plants , known as saxifrages or rockfoils . The Latin word saxifraga means literally "stone-breaker", from Latin saxum ("rock" or "stone") + frangere ("to break"). It is usually thought to indicate a medicinal use for treatment of urinary calculi (known as kidney or bladder stones), rather than breaking rocks apart. Most saxifrages are small perennial , biennial (e.g. S. adscendens ) or annual (e.g. S. tridactylites ) herbaceous plants whose basal or cauline leaves grow close to
174-423: A parasitic organism has as its habitat the body of its host , part of the host's body (such as the digestive tract), or a single cell within the host's body. Habitat types are environmental categorizations of different environments based on the characteristics of a given geographical area, particularly vegetation and climate. Thus habitat types do not refer to a single species but to multiple species living in
261-647: A conduit for the dispersal of pollen grains, spores and seeds , the atmosphere can be considered to be a habitat-type in its own right. There are metabolically active microbes present that actively reproduce and spend their whole existence airborne, with hundreds of thousands of individual organisms estimated to be present in a cubic meter of air. The airborne microbial community may be as diverse as that found in soil or other terrestrial environments, however, these organisms are not evenly distributed, their densities varying spatially with altitude and environmental conditions. Aerobiology has not been studied much, but there
348-489: A downpour occurs and lays its eggs in the transient pools that form; the tadpoles develop with great rapidity, sometimes in as little as nine days, undergo metamorphosis , and feed voraciously before digging a burrow of their own. Other organisms cope with the drying up of their aqueous habitat in other ways. Vernal pools are ephemeral ponds that form in the rainy season and dry up afterwards. They have their specially-adapted characteristic flora, mainly consisting of annuals,
435-413: A forest is divided into parts by logging, with strips of cleared land separating woodland blocks, and the distances between the remaining fragments exceeds the distance an individual animal is able to travel, that species becomes especially vulnerable. Small populations generally lack genetic diversity and may be threatened by increased predation, increased competition, disease and unexpected catastrophe. At
522-407: A genus is determined by taxonomists . The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including the idea that a newly defined genus should fulfill these three criteria to be descriptively useful: Moreover, genera should be composed of phylogenetic units of
609-526: A home for both static organisms, anchored to the substrate , and for a large range of organisms crawling on or burrowing into the surface. Some creatures float among the waves on the surface of the water, or raft on floating debris, others swim at a range of depths, including organisms in the demersal zone close to the seabed, and myriads of organisms drift with the currents and form the plankton . Many animals and plants have taken up residence in urban environments. They tend to be adaptable generalists and use
696-643: A later homonym of a validly published name is a nomen illegitimum or nom. illeg. ; for a full list refer to the International Code of Nomenclature for algae, fungi, and plants and the work cited above by Hawksworth, 2010. In place of the "valid taxon" in zoology, the nearest equivalent in botany is " correct name " or "current name" which can, again, differ or change with alternative taxonomic treatments or new information that results in previously accepted genera being combined or split. Prokaryote and virus codes of nomenclature also exist which serve as
783-621: A long time and redescribed as new by a range of subsequent workers, or if a range of genera previously considered separate taxa have subsequently been consolidated into one. For example, the World Register of Marine Species presently lists 8 genus-level synonyms for the sperm whale genus Physeter Linnaeus, 1758, and 13 for the bivalve genus Pecten O.F. Müller, 1776. Within the same kingdom, one generic name can apply to one genus only. However, many names have been assigned (usually unintentionally) to two or more different genera. For example,
870-709: A mile below the ice of Antarctica; in the absence of sunlight, they must rely on organic material from elsewhere, perhaps decaying matter from glacier melt water or minerals from the underlying rock. Other bacteria can be found in abundance in the Mariana Trench , the deepest place in the ocean and on Earth; marine snow drifts down from the surface layers of the sea and accumulates in this undersea valley, providing nourishment for an extensive community of bacteria. Other microbes live in environments lacking in oxygen, and are dependent on chemical reactions other than photosynthesis . Boreholes drilled 300 m (1,000 ft) into
957-444: A natural habitat is no longer able to support its native species. The organisms once living there have either moved to elsewhere or are dead, leading to a decrease in biodiversity and species numbers . Habitat destruction is in fact the leading cause of biodiversity loss and species extinction worldwide. The protection of habitat types is a necessary step in the maintenance of biodiversity because if habitat destruction occurs,
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#17331158016021044-410: A parasitic organism, its habitat is the particular part of the outside or inside of its host on or in which it is adapted to live. The life cycle of some parasites involves several different host species, as well as free-living life stages, sometimes within vastly different microhabitat types. One such organism is the trematode (flatworm) Microphallus turgidus , present in brackish water marshes in
1131-557: A particular species well, but its presence or absence at any particular location depends to some extent on chance, on its dispersal abilities and its efficiency as a colonizer. Arid habitats are those where there is little available water. The most extreme arid habitats are deserts . Desert animals have a variety of adaptations to survive the dry conditions. Some frogs live in deserts, creating moist habitat types underground and hibernating while conditions are adverse. Couch's spadefoot toad ( Scaphiopus couchii ) emerges from its burrow when
1218-409: A reference for designating currently accepted genus names as opposed to others which may be either reduced to synonymy, or, in the case of prokaryotes, relegated to a status of "names without standing in prokaryotic nomenclature". An available (zoological) or validly published (botanical) name that has been historically applied to a genus but is not regarded as the accepted (current/valid) name for
1305-487: A similar way; their eggs hatch and the juvenile fish grow with great rapidity when the conditions are right, but the whole population of fish may end up as eggs in diapause in the dried up mud that was once a pond. Freshwater habitat types include rivers, streams, lakes, ponds, marshes and bogs. They can be divided into running waters (rivers, streams) and standing waters (lakes, ponds, marshes, bogs). Although some organisms are found across most of these habitat types,
1392-509: A similarly rich fauna of invertebrates as a more varied habitat. The monotypic habitat occurs in both botanical and zoological contexts. Some invasive species may create monocultural stands that prevent other species from growing there. A dominant colonization can occur from retardant chemicals exuded, nutrient monopolization, or from lack of natural controls, such as herbivores or climate, that keep them in balance with their native habitat types. The yellow starthistle, Centaurea solstitialis
1479-427: A taxon; however, the names published in suppressed works are made unavailable via the relevant Opinion dealing with the work in question. In botany, similar concepts exist but with different labels. The botanical equivalent of zoology's "available name" is a validly published name . An invalidly published name is a nomen invalidum or nom. inval. ; a rejected name is a nomen rejiciendum or nom. rej. ;
1566-455: A total of c. 520,000 published names (including synonyms) as at end 2019, increasing at some 2,500 published generic names per year. "Official" registers of taxon names at all ranks, including genera, exist for a few groups only such as viruses and prokaryotes, while for others there are compendia with no "official" standing such as Index Fungorum for fungi, Index Nominum Algarum and AlgaeBase for algae, Index Nominum Genericorum and
1653-498: A variety of bacteria and fungi; and snowfields on which algae grow. Whether from natural processes or the activities of man, landscapes and their associated habitat types change over time. There are the slow geomorphological changes associated with the geologic processes that cause tectonic uplift and subsidence , and the more rapid changes associated with earthquakes, landslides, storms, flooding, wildfires, coastal erosion , deforestation and changes in land use. Then there are
1740-441: A violent event (such as the eruption of a volcano , an earthquake , a tsunami , a wildfire or a change in oceanic currents); or change may occur more gradually over millennia with alterations in the climate , as ice sheets and glaciers advance and retreat, and as different weather patterns bring changes of precipitation and solar radiation . Other changes come as a direct result of human activities, such as deforestation ,
1827-423: A wide range of Brassicas and various other plant species, and it thrives in any open location with diverse plant associations. The large blue butterfly Phengaris arion is much more specific in its requirements; it is found only in chalk grassland areas, its larvae feed on Thymus species, and because of complex life cycle requirements it inhabits only areas in which Myrmica ants live. Disturbance
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#17331158016021914-562: Is chemosynthesis , a process by which microbes convert such substances as hydrogen sulfide or ammonia into organic molecules. These bacteria and Archaea are the primary producers in these ecosystems and support a diverse array of life. About 350 species of organism, dominated by molluscs , polychaete worms and crustaceans , had been discovered around hydrothermal vents by the end of the twentieth century, most of them being new to science and endemic to these habitat types. Besides providing locomotion opportunities for winged animals and
2001-404: Is a concept sometimes used in conservation biology , in which a single species of animal or plant is the only species of its type to be found in a specific habitat and forms a monoculture . Even though it might seem such a habitat type is impoverished in biodiversity as compared with polytypic habitat types, this is not necessarily the case. Monocultures of the exotic plant Hydrilla support
2088-656: Is a food in Korea and Japan. The flowers of purple saxifrage ( S. oppositifolia ) are eaten in Nunavut , Canada and the leaves and stems brewed as a tea. Species are also used in traditional medicine, such as creeping saxifrage in East Asia and round-leaved saxifrage ( S. rotundifolia ) in Europe. Two species—purple saxifrage and creeping saxifrage—are popular floral emblems . They are official flowers for: Genus The composition of
2175-509: Is a vigorous grass from Europe which has been introduced to the United States where it has become invasive. It is highly adapted to fire, producing large amounts of flammable detritus and increasing the frequency and intensity of wildfires. In areas where it has become established, it has altered the local fire regimen to such an extant that native plants cannot survive the frequent fires, allowing it to become even more dominant. A marine example
2262-469: Is also abundant in the Eastern and Western Himalayan alpine shrub and meadows . Though the archetypal saxifrage is a small plant huddling between rocks high up on a mountain, many species do not occur in such a habitat and are larger (though still rather delicate) plants found on wet meadows . Various Saxifraga species are used as food plants by the caterpillars of some butterflies and moths , such as
2349-710: Is commonly grown as an ornamental plant . Another horticultural hybrid is Robertsoniana saxifrage ( S. × geum ), derived from kidney saxifrage ( S. hirsuta ) and Pyrenean saxifrage. Some wild species are also used in gardening. Cambridge University Botanic Garden hosts the United Kingdom's national collection of saxifrages. The following species and cultivars have gained the Royal Horticultural Society 's Award of Garden Merit :- The leaves of some saxifrage species, such as creeping saxifrage ( S. stolonifera ) and S. pensylvanica , are edible. The former
2436-596: Is discouraged by both the International Code of Zoological Nomenclature and the International Code of Nomenclature for algae, fungi, and plants , there are some five thousand such names in use in more than one kingdom. For instance, A list of generic homonyms (with their authorities), including both available (validly published) and selected unavailable names, has been compiled by the Interim Register of Marine and Nonmarine Genera (IRMNG). The type genus forms
2523-494: Is evidence of nitrogen fixation in clouds , and less clear evidence of carbon cycling, both facilitated by microbial activity. There are other examples of extreme habitat types where specially adapted lifeforms exist; tar pits teeming with microbial life; naturally occurring crude oil pools inhabited by the larvae of the petroleum fly ; hot springs where the temperature may be as high as 71 °C (160 °F) and cyanobacteria create microbial mats ; cold seeps where
2610-559: Is important in the creation of biodiverse habitat types. In the absence of disturbance, a climax vegetation cover develops that prevents the establishment of other species. Wildflower meadows are sometimes created by conservationists but most of the flowering plants used are either annuals or biennials and disappear after a few years in the absence of patches of bare ground on which their seedlings can grow. Lightning strikes and toppled trees in tropical forests allow species richness to be maintained as pioneering species move in to fill
2697-460: Is somewhat arbitrary. Although all species within a genus are supposed to be "similar", there are no objective criteria for grouping species into genera. There is much debate among zoologists about whether enormous, species-rich genera should be maintained, as it is extremely difficult to come up with identification keys or even character sets that distinguish all species. Hence, many taxonomists argue in favor of breaking down large genera. For instance,
Saxifraga - Misplaced Pages Continue
2784-474: Is the type species , and the generic name is permanently associated with the type specimen of its type species. Should the specimen turn out to be assignable to another genus, the generic name linked to it becomes a junior synonym and the remaining taxa in the former genus need to be reassessed. In zoological usage, taxonomic names, including those of genera, are classified as "available" or "unavailable". Available names are those published in accordance with
2871-416: Is the small-scale physical requirements of a particular organism or population. Every habitat includes large numbers of microhabitat types with subtly different exposure to light, humidity, temperature, air movement, and other factors. The lichens that grow on the north face of a boulder are different from those that grow on the south face, from those on the level top, and those that grow on the ground nearby;
2958-503: Is very challenging to research, and as well as being little-studied, it is vast, with 79% of the Earth's biosphere being at depths greater than 1,000 m (3,300 ft). With no plant life, the animals in this zone are either detritivores , reliant on food drifting down from surface layers, or they are predators, feeding on each other. Some organisms are pelagic , swimming or drifting in mid-ocean, while others are benthic, living on or near
3045-468: Is when sea urchin populations " explode " in coastal waters and destroy all the macroalgae present. What was previously a kelp forest becomes an urchin barren that may last for years and this can have a profound effect on the food chain . Removal of the sea urchins, by disease for example, can result in the seaweed returning, with an over-abundance of fast-growing kelp. Habitat destruction (also termed habitat loss and habitat reduction) occurs when
3132-621: The International Code of Zoological Nomenclature ; the earliest such name for any taxon (for example, a genus) should then be selected as the " valid " (i.e., current or accepted) name for the taxon in question. Consequently, there will be more available names than valid names at any point in time; which names are currently in use depending on the judgement of taxonomists in either combining taxa described under multiple names, or splitting taxa which may bring available names previously treated as synonyms back into use. "Unavailable" names in zoology comprise names that either were not published according to
3219-799: The International Plant Names Index for plants in general, and ferns through angiosperms, respectively, and Nomenclator Zoologicus and the Index to Organism Names for zoological names. Totals for both "all names" and estimates for "accepted names" as held in the Interim Register of Marine and Nonmarine Genera (IRMNG) are broken down further in the publication by Rees et al., 2020 cited above. The accepted names estimates are as follows, broken down by kingdom: The cited ranges of uncertainty arise because IRMNG lists "uncertain" names (not researched therein) in addition to known "accepted" names;
3306-550: The Latin habitāre , to inhabit, from habēre , to have or to hold. Habitat can be defined as the natural environment of an organism , the type of place in which it is natural for it to live and grow. It is similar in meaning to a biotope ; an area of uniform environmental conditions associated with a particular community of plants and animals. The chief environmental factors affecting the distribution of living organisms are temperature, humidity, climate, soil and light intensity , and
3393-502: The methane and hydrogen sulfide issue from the ocean floor and support microbes and higher animals such as mussels which form symbiotic associations with these anaerobic organisms ; salt pans that harbour salt-tolerant bacteria , archaea and also fungi such as the black yeast Hortaea werneckii and basidiomycete Wallemia ichthyophaga ; ice sheets in Antarctica which support fungi Thelebolus spp., glacial ice with
3480-419: The nomenclature codes , which allow each species a single unique name that, for animals (including protists ), plants (also including algae and fungi ) and prokaryotes ( bacteria and archaea ), is Latin and binomial in form; this contrasts with common or vernacular names , which are non-standardized, can be non-unique, and typically also vary by country and language of usage. Except for viruses ,
3567-467: The photic zone in the oceans are relatively familiar habitat types. However the vast bulk of the ocean is inhospitable to air-breathing humans, with scuba divers limited to the upper 50 m (160 ft) or so. The lower limit for photosynthesis is 100 to 200 m (330 to 660 ft) and below that depth the prevailing conditions include total darkness, high pressure, little oxygen (in some places), scarce food resources and extreme cold. This habitat
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3654-404: The platypus belongs to the genus Ornithorhynchus although George Shaw named it Platypus in 1799 (these two names are thus synonyms ) . However, the name Platypus had already been given to a group of ambrosia beetles by Johann Friedrich Wilhelm Herbst in 1793. A name that means two different things is a homonym . Since beetles and platypuses are both members of the kingdom Animalia,
3741-454: The plowing of ancient grasslands, the diversion and damming of rivers, the draining of marshland and the dredging of the seabed. The introduction of alien species can have a devastating effect on native wildlife – through increased predation , through competition for resources or through the introduction of pests and diseases to which the indigenous species have no immunity. The word "habitat" has been in use since about 1755 and derives from
3828-476: The Phoebus Apollo ( Parnassius phoebus ). Charles Darwin – erroneously believing Saxifraga to be allied to the sundew family ( Droseraceae ) – suspected the sticky-leaved round-leaved saxifrage ( S. rotundifolia ), rue-leaved saxifrage ( S. tridactylites ) and Pyrenean saxifrage ( S. umbrosa ) to be protocarnivorous plants , and conducted some experiments whose results supported his observations, but
3915-436: The animals and plants reliant on that habitat suffer. Many countries have enacted legislation to protect their wildlife. This may take the form of the setting up of national parks, forest reserves and wildlife reserves, or it may restrict the activities of humans with the objective of benefiting wildlife. The laws may be designed to protect a particular species or group of species, or the legislation may prohibit such activities as
4002-442: The base for higher taxonomic ranks, such as the family name Canidae ("Canids") based on Canis . However, this does not typically ascend more than one or two levels: the order to which dogs and wolves belong is Carnivora ("Carnivores"). The numbers of either accepted, or all published genus names is not known precisely; Rees et al., 2020 estimate that approximately 310,000 accepted names (valid taxa) may exist, out of
4089-416: The changes in habitat types brought on by alterations in farming practices, tourism, pollution, fragmentation and climate change. Loss of habitat is the single greatest threat to any species. If an island on which an endemic organism lives becomes uninhabitable for some reason, the species will become extinct . Any type of habitat surrounded by a different habitat is in a similar situation to an island. If
4176-455: The collecting of bird eggs, the hunting of animals or the removal of plants. A general law on the protection of habitat types may be more difficult to implement than a site specific requirement. A concept introduced in the United States in 1973 involves protecting the critical habitat of endangered species , and a similar concept has been incorporated into some Australian legislation. International treaties may be necessary for such objectives as
4263-420: The edge of each forest fragment, increased light encourages secondary growth of fast-growing species and old growth trees are more vulnerable to logging as access is improved. The birds that nest in their crevices, the epiphytes that hang from their branches and the invertebrates in the leaf litter are all adversely affected and biodiversity is reduced. Habitat fragmentation can be ameliorated to some extent by
4350-446: The form "author, year" in zoology, and "standard abbreviated author name" in botany. Thus in the examples above, the genus Canis would be cited in full as " Canis Linnaeus, 1758" (zoological usage), while Hibiscus , also first established by Linnaeus but in 1753, is simply " Hibiscus L." (botanical usage). Each genus should have a designated type , although in practice there is a backlog of older names without one. In zoology, this
4437-745: The gaps created. Similarly, coastal habitat types can become dominated by kelp until the seabed is disturbed by a storm and the algae swept away, or shifting sediment exposes new areas for colonisation. Another cause of disturbance is when an area may be overwhelmed by an invasive introduced species which is not kept under control by natural enemies in its new habitat. Terrestrial habitat types include forests, grasslands, wetlands and deserts. Within these broad biomes are more specific habitat types with varying climate types, temperature regimes, soils, altitudes and vegetation. Many of these habitat types grade into each other and each one has its own typical communities of plants and animals. A habitat-type may suit
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#17331158016024524-727: The generic name (or its abbreviated form) still forms the leading portion of the scientific name, for example, Canis lupus lupus for the Eurasian wolf subspecies, or as a botanical example, Hibiscus arnottianus ssp. immaculatus . Also, as visible in the above examples, the Latinised portions of the scientific names of genera and their included species (and infraspecies, where applicable) are, by convention, written in italics . The scientific names of virus species are descriptive, not binomial in form, and may or may not incorporate an indication of their containing genus; for example,
4611-444: The ground, often in a rosette . The leaves typically have a more or less incised margin; they may be succulent , needle-like and/or hairy, reducing evaporation . The inflorescence or single flower clusters rise above the main plant body on naked stalks. The small actinomorphic hermaphrodite flowers have five petals and sepals and are usually white, but red to yellow in some species. Stamens , usually 10, rarely 8, insert at
4698-548: The junction of the floral tube and ovary wall, with filaments subulate or clavate. As in other primitive eudicots , some of the 5 or 10 stamens may appear petal-like. and it lives in tundral ecosystems. A genus of about 473 species. The former monotypic genus Saxifragella has been submersed within Saxifraga, the largest genus in Saxifragaceae , as Saxifraga bicuspidata . Also the genus Saxifragopsis (strawberry saxifrage)
4785-628: The largest component, with 23,236 ± 5,379 accepted genus names, of which 20,845 ± 4,494 are angiosperms (superclass Angiospermae). By comparison, the 2018 annual edition of the Catalogue of Life (estimated >90% complete, for extant species in the main) contains currently 175,363 "accepted" genus names for 1,744,204 living and 59,284 extinct species, also including genus names only (no species) for some groups. The number of species in genera varies considerably among taxonomic groups. For instance, among (non-avian) reptiles , which have about 1180 genera,
4872-720: The lichens growing in the grooves and on the raised surfaces are different from those growing on the veins of quartz. Lurking among these miniature "forests" are the microfauna , species of invertebrate , each with its own specific habitat requirements. There are numerous different microhabitat types in a wood; coniferous forest, broad-leafed forest, open woodland, scattered trees, woodland verges, clearings, and glades; tree trunk, branch, twig, bud, leaf, flower, and fruit; rough bark, smooth bark, damaged bark, rotten wood, hollow, groove, and hole; canopy, shrub layer, plant layer, leaf litter , and soil; buttress root, stump, fallen log, stem base, grass tussock, fungus, fern, and moss. The greater
4959-413: The lizard genus Anolis has been suggested to be broken down into 8 or so different genera which would bring its ~400 species to smaller, more manageable subsets. Habitat In ecology , habitat refers to the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species . A species habitat can be seen as
5046-531: The majority have more specific requirements. The water velocity, its temperature and oxygen saturation are important factors, but in river systems, there are fast and slow sections, pools, bayous and backwaters which provide a range of habitat types. Similarly, aquatic plants can be floating, semi-submerged, submerged or grow in permanently or temporarily saturated soils besides bodies of water. Marginal plants provide important habitat for both invertebrates and vertebrates, and submerged plants provide oxygenation of
5133-436: The matter has apparently not been studied since his time. Numerous species and cultivars of saxifrage are cultivated as ornamental garden plants, valued particularly as groundcover or as cushion plants in rock gardens and alpine gardens . Many require alkaline or neutral soil to thrive. S. × urbium (London pride), a hybrid between Pyrenean saxifrage ( S. umbrosa ) and St. Patrick's cabbage ( S. spathularis ),
5220-403: The most (>300) have only 1 species, ~360 have between 2 and 4 species, 260 have 5–10 species, ~200 have 11–50 species, and only 27 genera have more than 50 species. However, some insect genera such as the bee genera Lasioglossum and Andrena have over 1000 species each. The largest flowering plant genus, Astragalus , contains over 3,000 species. Which species are assigned to a genus
5307-428: The name could not be used for both. Johann Friedrich Blumenbach published the replacement name Ornithorhynchus in 1800. However, a genus in one kingdom is allowed to bear a scientific name that is in use as a generic name (or the name of a taxon in another rank) in a kingdom that is governed by a different nomenclature code. Names with the same form but applying to different taxa are called "homonyms". Although this
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#17331158016025394-515: The needs of the local residents for food, fuel and other resources. Faced with hunger and destitution, a farmer is likely to plough up a level patch of ground despite it being the last suitable habitat for an endangered species such as the San Quintin kangaroo rat , and even kill the animal as a pest. In the interests of ecotourism it is desirable that local communities are educated on the uniqueness of their flora and fauna. A monotypic habitat type
5481-412: 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. The physical factors may include (for example): soil , moisture , range of temperature , and light intensity . Biotic factors include the availability of food and
5568-414: The presence or absence of predators . Every species has particular habitat requirements, habitat generalist species are able to thrive in a wide array of environmental conditions while habitat specialist species require a very limited set of factors to survive. The habitat of a species is not necessarily found in a geographical area, it can be the interior of a stem, a rotten log, a rock or a clump of moss ;
5655-419: The presence or absence of all the requirements that the organism needs to sustain it. Generally speaking, animal communities are reliant on specific types of plant communities. Some plants and animals have habitat requirements which are met in a wide range of locations. The small white butterfly Pieris rapae for example is found on all the continents of the world apart from Antarctica . Its larvae feed on
5742-545: The proteins the flexibility they need. There are also unsaturated fats in their membranes which prevent them from solidifying at low temperatures. Hydrothermal vents were first discovered in the ocean depths in 1977. They result from seawater becoming heated after seeping through cracks to places where hot magma is close to the seabed. The under-water hot springs may gush forth at temperatures of over 340 °C (640 °F) and support unique communities of organisms in their immediate vicinity. The basis for this teeming life
5829-428: The provision of wildlife corridors connecting the fragments. These can be a river, ditch, strip of trees, hedgerow or even an underpass to a highway. Without the corridors, seeds cannot disperse and animals, especially small ones, cannot travel through the hostile territory, putting populations at greater risk of local extinction . Habitat disturbance can have long-lasting effects on the environment. Bromus tectorum
5916-526: The provisions of the ICZN Code, e.g., incorrect original or subsequent spellings, names published only in a thesis, and generic names published after 1930 with no type species indicated. According to "Glossary" section of the zoological Code, suppressed names (per published "Opinions" of the International Commission of Zoological Nomenclature) remain available but cannot be used as the valid name for
6003-573: The rocky seabed have found microbial communities apparently based on the products of reactions between water and the constituents of rocks. These communities have not been studied much, but may be an important part of the global carbon cycle . Rock in mines two miles deep also harbour microbes; these live on minute traces of hydrogen produced in slow oxidizing reactions inside the rock. These metabolic reactions allow life to exist in places with no oxygen or light, an environment that had previously been thought to be devoid of life. The intertidal zone and
6090-441: The same area. For example, terrestrial habitat types include forest , steppe , grassland , semi-arid or desert . Fresh-water habitat types include marshes , streams , rivers , lakes , and ponds ; marine habitat types include salt marshes, the coast, the intertidal zone , estuaries , reefs , bays, the open sea, the sea bed, deep water and submarine vents . Habitat types may change over time. Causes of change may include
6177-466: The same kind as other (analogous) genera. The term "genus" comes from Latin genus , a noun form cognate with gignere ('to bear; to give birth to'). The Swedish taxonomist Carl Linnaeus popularized its use in his 1753 Species Plantarum , but the French botanist Joseph Pitton de Tournefort (1656–1708) is considered "the founder of the modern concept of genera". The scientific name (or
6264-624: The saxifrage genus: Saxifrages are typical inhabitants of Arctic–alpine ecosystems , and are hardly ever found outside the temperate parts of the Northern Hemisphere; most members of this genus are found in subarctic climates. A good number of species grow in glacial habitats, such as S. biflora which can be found some 4,000 m (13,000 ft) above sea level in the Alps, or the East Greenland saxifrage ( S. nathorstii ). The genus
6351-408: The scientific epithet) of a genus is also called the generic name ; in modern style guides and science, it is always capitalised. It plays a fundamental role in binomial nomenclature , the system of naming organisms , where it is combined with the scientific name of a species : see Botanical name and Specific name (zoology) . The rules for the scientific names of organisms are laid down in
6438-565: The seabed. Their growth rates and metabolisms tend to be slow, their eyes may be very large to detect what little illumination there is, or they may be blind and rely on other sensory inputs. A number of deep sea creatures are bioluminescent ; this serves a variety of functions including predation, protection and social recognition. In general, the bodies of animals living at great depths are adapted to high pressure environments by having pressure-resistant biomolecules and small organic molecules present in their cells known as piezolytes , which give
6525-400: The seeds of which survive the drought, but also some uniquely adapted perennials. Animals adapted to these extreme habitat types also exist; fairy shrimps can lay "winter eggs" which are resistant to desiccation , sometimes being blown about with the dust, ending up in new depressions in the ground. These can survive in a dormant state for as long as fifteen years. Some killifish behave in
6612-519: The setting up of marine reserves. Another international agreement, the Convention on the Conservation of Migratory Species of Wild Animals , protects animals that migrate across the globe and need protection in more than one country. Even where legislation protects the environment, a lack of enforcement often prevents effective protection. However, the protection of habitat types needs to take into account
6699-528: The southeastern United States. Its first intermediate host is a snail and the second, a glass shrimp . The final host is the waterfowl or mammal that consumes the shrimp. Although the vast majority of life on Earth lives in mesophyllic (moderate) environments, a few organisms, most of them microbes , have managed to colonise extreme environments that are unsuitable for more complex life forms. There are bacteria , for example, living in Lake Whillans , half
6786-497: The specific name particular to the wolf. A botanical example would be Hibiscus arnottianus , a particular species of the genus Hibiscus native to Hawaii. The specific name is written in lower-case and may be followed by subspecies names in zoology or a variety of infraspecific names in botany . When the generic name is already known from context, it may be shortened to its initial letter, for example, C. lupus in place of Canis lupus . Where species are further subdivided,
6873-412: The standard format for a species name comprises the generic name, indicating the genus to which the species belongs, followed by the specific epithet, which (within that genus) is unique to the species. For example, the gray wolf 's scientific name is Canis lupus , with Canis ( Latin for 'dog') being the generic name shared by the wolf's close relatives and lupus (Latin for 'wolf') being
6960-554: The structural diversity in the wood, the greater the number of microhabitat types that will be present. A range of tree species with individual specimens of varying sizes and ages, and a range of features such as streams, level areas, slopes, tracks, clearings, and felled areas will provide suitable conditions for an enormous number of biodiverse plants and animals. For example, in Britain it has been estimated that various types of rotting wood are home to over 1700 species of invertebrate. For
7047-403: The taxon is termed a synonym ; some authors also include unavailable names in lists of synonyms as well as available names, such as misspellings, names previously published without fulfilling all of the requirements of the relevant nomenclatural code, and rejected or suppressed names. A particular genus name may have zero to many synonyms, the latter case generally if the genus has been known for
7134-455: The town's features to make their homes. Rats and mice have followed man around the globe, pigeons , peregrines , sparrows , swallows and house martins use the buildings for nesting, bats use roof space for roosting, foxes visit the garbage bins and squirrels , coyotes , raccoons and skunks roam the streets. About 2,000 coyotes are thought to live in and around Chicago . A survey of dwelling houses in northern European cities in
7221-418: The twentieth century found about 175 species of invertebrate inside them, including 53 species of beetle, 21 flies, 13 butterflies and moths, 13 mites, 9 lice, 7 bees, 5 wasps, 5 cockroaches, 5 spiders, 4 ants and a number of other groups. In warmer climates, termites are serious pests in the urban habitat; 183 species are known to affect buildings and 83 species cause serious structural damage. A microhabitat
7308-566: The values quoted are the mean of "accepted" names alone (all "uncertain" names treated as unaccepted) and "accepted + uncertain" names (all "uncertain" names treated as accepted), with the associated range of uncertainty indicating these two extremes. Within Animalia, the largest phylum is Arthropoda , with 151,697 ± 33,160 accepted genus names, of which 114,387 ± 27,654 are insects (class Insecta). Within Plantae, Tracheophyta (vascular plants) make up
7395-429: The virus species " Salmonid herpesvirus 1 ", " Salmonid herpesvirus 2 " and " Salmonid herpesvirus 3 " are all within the genus Salmonivirus ; however, the genus to which the species with the formal names " Everglades virus " and " Ross River virus " are assigned is Alphavirus . As with scientific names at other ranks, in all groups other than viruses, names of genera may be cited with their authorities, typically in
7482-460: The water, absorb nutrients and play a part in the reduction of pollution. Rivers Ponds Lakes Marine habitats include brackish water, estuaries, bays, the open sea, the intertidal zone, the sea bed, reefs and deep / shallow water zones. Further variations include rock pools , sand banks , mudflats , brackish lagoons, sandy and pebbly beaches, and seagrass beds, all supporting their own flora and fauna. The benthic zone or seabed provides
7569-936: Was previously included in Saxifraga . Based on morphological criteria, up to 15 sections were recognised. Subsequent molecular phylogenetic studies reduced this to 13 sections with 9 subsections. The former sections Micranthes and Merkianae are more closely related to the Boykinia and Heuchera clades . Modern floras separate these groups as the genus Micranthes . The thirteen sections (with subsections) are: Plants formerly placed in Saxifraga are mainly but not exclusively Saxifragaceae . They include: Several plant genera have names referring to saxifrages, although they might not be close relatives of Saxifraga . They include: Some plants refer to Saxifraga in their generic names or specific epithets , either because they are also "rock-breaking" or because they resemble members of
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