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Lake Chichancanab
Lake Chichancanab is a lake in Mexico located in the northwest of the state of Quintana Roo, in the municipality of José María Morelos. It is also known as Laguna Chichancanab, Laguna Chicnancanab and Laguna de Chichancanab. It has an approximate length of 30 kilometers from near the settlement of La Presumida to that of Kantemó, in the same municipality. It is the largest lake on the Yucatan Peninsula. The lake has a clay lake bed which seals the water off from the bedrock the water level is therefore determined by the balance between rainfall and evaporation. The lakes waters are saline, with high concentrations of dissolved minerals. When the area undergoes drought for a sufficiently long period then gypsum precipitates and concentrates in the mud on the lake bed. In the last five thousand years, this deposit of gypsum has occurred at just one period which coincided with the start of the decline of the classical Mayan civilisation. On 2 February 2004, Lake Chichancanab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endorheic
An endorheic basin (; also spelled endoreic basin or endorreic basin) is a drainage basin that normally retains water and allows no outflow to other external bodies of water, such as rivers or oceans, but drainage converges instead into lakes or swamps, permanent or seasonal, that equilibrate through evaporation. They are also called closed or terminal basins, internal drainage systems, or simply basins. Endorheic regions contrast with open and closed lakes, exorheic regions. Endorheic water bodies include some of the largest lakes in the world, such as the Caspian Sea, the world's largest inland body of water. Basins with subsurface outflows which eventually lead to the ocean are generally not considered endorheic; they are cryptorheic. Endorheic basins constitute local base levels, defining a limit of erosion and deposition processes of nearby areas. Etymology The term was borrowed from French ''endor(rh)éisme'', coined from the combining form ''endo-'' (from grc, ἔν ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyprinodon Esconditus
''Cyprinodon'' is a genus of pupfishes found in waters that range from fresh to hypersaline. The genus is primarily found in Mexico, the Caribbean Islands and southern United States (Arizona, California, Florida, Nevada, New Mexico, Oklahoma and Texas), but ''C. variegatus'' occurs as far north as Massachusetts and along the entire Gulf of Mexico coastline, and ''C. dearborni '' and ''C. variegatus'' are found in northern South America.Martin, C. H., and P. C. Wainwright (2013). ''Multiple Fitness Peaks on the Adaptive Landscape Drive Adaptive Radiation in the Wild.'' Science 339(6116): 208-211. Many species have tiny ranges and are highly threatened, in some cases already extinct. ''Cyprinodon'' are small; the largest reaches in length and most other species only reach about half that size. Distribution and habitat A few ''Cyprinodon'' species have quite large ranges, notably '' C. variegatus'', but the vast majority have small ranges, typically restricted to one or two Mexi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nile Tilapia
The Nile tilapia (''Oreochromis niloticus'') is a species of tilapia, a cichlid fish native to the northern half of Africa and the Levante area, including Israel, and Lebanon. Numerous introduced populations exist outside its natural range. It is also commercially known as mango fish, nilotica, or boulti. The first name leads to easy confusion with another tilapia which is traded commercially, the mango tilapia (''Sarotherodon galilaeus''). Description The Nile tilapia reaches up to in length, and can exceed . As typical of tilapia, males reach a larger size and grow faster than females. Wild, natural-type Nile tilapias are brownish or grayish overall, often with indistinct banding on their body, and the tail is vertically striped. When breeding, males become reddish, especially on their fins. Although commonly confused with the blue tilapia (''O. aureus''), that species lacks the striped tail pattern, has a red edge to the dorsal fin (this edge is gray or black in Nile tilap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Introduced Species
An introduced species, alien species, exotic species, adventive species, immigrant species, foreign species, non-indigenous species, or non-native species is a species living outside its native distributional range, but which has arrived there by human activity, directly or indirectly, and either deliberately or accidentally. Non-native species can have various effects on the local ecosystem. Introduced species that become established and spread beyond the place of introduction are considered naturalized. The process of human-caused introduction is distinguished from biological colonization, in which species spread to new areas through "natural" (non-human) means such as storms and rafting. The Latin expression neobiota captures the characteristic that these species are ''new'' biota to their environment in terms of established biological network (e.g. food web) relationships. Neobiota can further be divided into neozoa (also: neozoons, sing. neozoon, i.e. animals) and neophyt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extinct In The Wild
A species that is extinct in the wild (EW) is one that has been categorized by the International Union for Conservation of Nature as known only by living members kept in captivity or as a naturalized population outside its historic range due to massive habitat loss. Examples Examples of species and subspecies that are extinct in the wild include: *Alagoas curassow (last unconfirmed sighting reported in the late 1980s, listed extinct in the wild since 1994) *Beloribitsa * Cachorrito de charco palmal (last seen in 1994, listed extinct in the wild since 1996) * Christmas Island blue-tailed skink (listed extinct in the wild since 2014) *Dabry's sturgeon (listed extinct in the wild since 2022) * Escarpment cycad (listed extinct in the wild since 2006) *Franklinia (last seen in 1803, listed extinct in the wild since 1998) *Golden skiffia (listed extinct in the wild since 1996) *Guam kingfisher (listed extinct in the wild since 1986) *Hawaiian crow or ʻalalā (last seen in 2002, li ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endemism
Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsewhere. For example, the Cape sugarbird is found exclusively in southwestern South Africa and is therefore said to be ''endemic'' to that particular part of the world. An endemic species can be also be referred to as an ''endemism'' or in scientific literature as an ''endemite''. For example '' Cytisus aeolicus'' is an endemite of the Italian flora. '' Adzharia renschi'' was once believed to be an endemite of the Caucasus, but it was later discovered to be a non-indigenous species from South America belonging to a different genus. The extreme opposite of an endemic species is one with a cosmopolitan distribution, having a global or widespread range. A rare alternative term for a species that is endemic is "precinctive", which applies to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Detritus
In biology, detritus () is dead particulate organic material, as distinguished from dissolved organic material. Detritus typically includes the bodies or fragments of bodies of dead organisms, and fecal material. Detritus typically hosts communities of microorganisms that colonize and decompose (i.e. remineralize) it. In terrestrial ecosystems it is present as leaf litter and other organic matter that is intermixed with soil, which is denominated " soil organic matter". The detritus of aquatic ecosystems is organic material that is suspended in the water and accumulates in depositions on the floor of the body of water; when this floor is a seabed, such a deposition is denominated "marine snow". Theory The corpses of dead plants or animals, material derived from animal tissues (e.g. molted skin), and fecal matter gradually lose their form due to physical processes and the action of decomposers, including grazers, bacteria, and fungi. Decomposition, the process by which or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ecological Niche
In ecology, a niche is the match of a species to a specific environmental condition. Three variants of ecological niche are described by It describes how an organism or population responds to the distribution of resources and competitors (for example, by growing when resources are abundant, and when predators, parasites and pathogens are scarce) and how it in turn alters those same factors (for example, limiting access to resources by other organisms, acting as a food source for predators and a consumer of prey). "The type and number of variables comprising the dimensions of an environmental niche vary from one species to another ndthe relative importance of particular environmental variables for a species may vary according to the geographic and biotic contexts". See also Chapter 2: Concepts of niches, pp. 7 ''ff'' A Grinnellian niche is determined by the habitat in which a species lives and its accompanying behavioral adaptations. An Eltonian niche emphasizes that a spec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
San Salvador Island
San Salvador Island (known as Watling's Island from the 1680s until 1925) is an island and district of The Bahamas. It is widely believed that during Christopher Columbus's first expedition to the New World, this island was the first land he sighted and visited on 12 October 1492. He named it ''San Salvador'' after Christ the Saviour. Columbus's records indicate that the native Lucayan inhabitants of the territory, who called their island Guanahaní, were "sweet and gentle". History When he made landfall on the small island of San Salvador in October 1492, Columbus thought he had reached the East Indies, which was precisely his quest: to find an all-water route to the Orient so that European traders of precious spices could maximise their profits by cutting out Muslim middlemen. Additionally and more specifically, he was working on behalf of the Spanish to surpass the Portuguese, who had established trade routes around the Horn of Africa, a trans-Atlantic route being presume ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sympatry
In biology, two related species or populations are considered sympatric when they exist in the same geographic area and thus frequently encounter one another. An initially interbreeding population that splits into two or more distinct species sharing a common range exemplifies sympatric speciation. Such speciation may be a product of reproductive isolation – which prevents hybrid offspring from being viable or able to reproduce, thereby reducing gene flow – that results in genetic divergence. Sympatric speciation may, but need not, arise through secondary contact, which refers to speciation or divergence in allopatry followed by range expansions leading to an area of sympatry. Sympatric species or taxa in secondary contact may or may not interbreed. Types of populations Four main types of population pairs exist in nature. Sympatric populations (or species) contrast with parapatric populations, which contact one another in adjacent but not shared ranges and do not ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species Flock
In biology, a species complex is a group of closely related organisms that are so similar in appearance and other features that the boundaries between them are often unclear. The taxa in the complex may be able to hybridize readily with each other, further blurring any distinctions. Terms that are sometimes used synonymously but have more precise meanings are cryptic species for two or more species hidden under one species name, sibling species for two (or more) species that are each other's closest relative, and species flock for a group of closely related species that live in the same habitat. As informal taxonomic ranks, species group, species aggregate, macrospecies, and superspecies are also in use. Two or more taxa that were once considered conspecific (of the same species) may later be subdivided into infraspecific taxa (taxa within a species, such as bacterial strains or plant varieties), that is complex but it is not a species complex. A species complex is in most ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyprinodon Verecundus
The largefin pupfish (''Cyprinodon verecundus''), also known as cachorrito de dorsal larga, is a small species of pupfish in the family Cyprinodontidae. It is endemic to Lake Chichancanab in Quintana Roo, Mexico. In almost all places, different ''Cyprinodon'' species do not overlap in their range, but there are two notable exceptions and one of these is Lake Chichancanab, which is inhabited by ''C. verecundus'', '' C. beltrani'', '' C. esconditus'', '' C. labiosus'', '' C. maya'', '' C. simus'' and '' C. suavium'' (the other place where several ''Cyprinodon'' species live together are lakes in San Salvador Island, the Bahamas). Living together, the ''Cyprinodon'' species in Lake Chichancanab have diverged into different niches. Pupfish typically feed on algae and detritus. In Lake Chichancanab, however, ''C. verecundus'' has become an amphipod- and bivalve-eater. The IUCN last reviewed ''C. verecundus'' in 2019 where they considered it vulnerable. Among the endemic ''Cyprinodon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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