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99-520: Traditionally a popular and affordable food in the Philippines with a mild taste, tilapia has been the fourth-most consumed fish in the United States since 2002, favored for its low cost and easy preparation. It is commonly fried or broiled as part of a dish. The common name "tilapia" is based on the name of the cichlid genus Tilapia , which is itself a latinization of either tlhapi ,

198-471: A skin graft material, for Müllerian agenesis , vaginal stenosis , and gender-affirming surgery . The skin-growing properties of tilapia skin are believed to be linked to its high type I collagen content and structural similarities to human skin. The material is also quite strong despite its low thickness. The current procedure for skin use calls for chemical sterilization with chlorhexidine, immersion in glycerol , followed by gamma ray sterilization, plus

297-752: A "traditional" dish, was first introduced in the Philippines in 1950 with Mozambique tilapia followed by Nile tilapia in 1972 from Thailand. Strains such as terapon (gunggong) and white goby ( biyang puti ) were abundant in Laguna de Bay . In 1988, WorldFish , Filipino and Norwegian researchers started aquaculture of the Genetically Improved Farmed Tilapia (GIFT). Other methods of tilapia population control are polyculture , with predators farmed alongside tilapia or hybridization with other species. Tilapia, introduced to

396-529: A 2019 study has shown that nine species of monogeneans were carried by introduced tilapia. Cichlid Alternate taxonomy: For genera , see below . Cichlids / ˈ s ɪ k l ɪ d z / are fish from the family Cichlidae in the order Cichliformes . Traditionally Cichlids were classed in a suborder, the Labroidei , along with the wrasses ( Labridae ), in the order Perciformes , but molecular studies have contradicted this grouping. On

495-731: A bandage is first used in a 2017 clinical trial to treat burn injuries, after successful trial in rats. In the United States, tilapia skin has been used to successfully treat third-degree wounds to the paws of two black bears caught in California's Thomas wildfire , and also to treat burns on the paws of a black bear from California's Carr wildfire . Nile tilapia skin has completed a phase III clinical trial for superficial partial-thickness burns. The fish skin group showed faster healing, lower pain, reduced dressing changes, and lower treatment costs compared to silver sulfadiazine cream control. Nile tilapia skin has also been used in neovaginoplasty as

594-419: A behavioral change such that they become less receptive to outside interactions. This is often coupled with some physiological change in appearance. Cichlids can have maternal, paternal, or biparental care. Maternal care is most common among mouthbrooders, but cichlids' common ancestor is thought to exhibit paternal-only care. Other individuals outside of the parents may also play a role in raising young; in

693-433: A consumption of 2.5 million. In modern aquaculture , wild-type Nile tilapia are not too often seen, as the dark color of their flesh is not much desired by many customers, and because it has a bit of a reputation of being a rough fish associated with poverty. However, they are fast-growing and give good fillets ; leucistic ("red") breeds which have lighter meat have been developed and are very popular. Hybrid stock

792-642: A few other genera, notably Oreochromis , and Sarotherodon . Even with this modification, apparently Tilapia was strongly poly– or paraphyletic . In 2013, a major taxonomic review resolved this by moving most former Tilapia spp. to several other genera. As a consequence, none of the species that are of major economic importance remain in Tilapia , but are instead placed in Coptodon , Oreochormis , and Sarotherodon . Tilapia have been used as biological controls for certain aquatic plant problems. They have

891-456: A few washes with saline in between. As with most fish, tilapia harbor a variety of parasites . For the monogeneans , these especially include species of the megadiverse genus Cichlidogyrus , which are gill parasites. Species of Enterogyrus are parasites in the digestive system. Tilapia, as important aquaculture fishes, have been introduced widely all over the world, and often carried their monogenean parasites with them. In South China ,

990-539: A food source, though, because they grow rapidly and tolerate high stocking densities and poor water quality. Smaller West African species, such as Coelotilapia joka and species from the crater lakes of Cameroon , are more popular as aquarium fish. In specialised cichlid aquaria, tilapia can be mixed successfully with nonterritorial cichlids, armored catfish , tinfoil barbs , garpike , and other robust fish. Some species, including Heterotilapia buttikoferi , Coptodon rendalli , Pelmatolapia mariae , C. joka , and

1089-399: A goal to identify and eliminate groups that are found to be polyphyletic. This is often the stimulus for major revisions of the classification schemes. Researchers concerned more with ecology than with systematics may take polyphyletic groups as legitimate subject matter; the similarities in activity within the fungus group Alternaria , for example, can lead researchers to regard the group as

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1188-468: A group, cichlids exhibit a similar diversity of body shapes, ranging from strongly laterally compressed species (such as Altolamprologus , Pterophyllum , and Symphysodon ) to species that are cylindrical and highly elongated (such as Julidochromis , Teleogramma , Teleocichla , Crenicichla , and Gobiocichla ). Generally, however, cichlids tend to be of medium size, ovate in shape, and slightly laterally compressed, and generally similar to

1287-434: A less nutritious fish than generally believed. The fish's omega-3 fatty acid content is often far lower than that of other commonly eaten fish species. Their omega-6 fatty acid levels are unusually high. Multiple studies have evaluated the effects of adding flaxseed derivatives (a vegetable source of omega-3 fatty acids) to the feed of farmed tilapia. These studies have found both the more common omega-3 fatty acid found in

1386-401: A male and female leads to courtship. Courtship in male cichlids follows the establishment of some form of territory, sometimes coupled with building a bower to attract mates. After this, males may attempt to attract female cichlids to their territories by a variety of lekking display strategies or otherwise seek out females of their species. However, cichlids, at the time of spawning, undergo

1485-604: A mating partner is unavailable. Pit spawning, also referred to as substrate breeding, is a behavior in cichlid fish in which a fish builds a pit in the sand or ground, where a pair court and consequently spawn. Many different factors go into this behavior of pit spawning, including female choice of the male and pit size, as well as the male defense of the pits once they are dug in the sand. Cichlids are often divided into two main groups: mouthbrooders and substrate brooders. Different parenting investment levels and behaviors are associated with each type of reproduction. As pit spawning

1584-480: A minor part of their diets. Other cichlids are detritivores and eat organic material, called Aufwuchs (offal); among these species are the tilapiines of the genera Oreochromis , Sarotherodon , and Tilapia . Other cichlids are predatory and eat little or no plant matter. These include generalists that catch a variety of small animals, including other fishes and insect larvae (e.g. Pterophyllum ), as well as variety of specialists. Trematocranus

1683-507: A mixed school of young have also been observed in multiple cichlid species, including Amphilophus citrinellus , Etroplus suratensis , and Tilapia rendalli . Comparably, the fry of Neolamprologus brichardi , a species that commonly lives in large groups, are protected not only by the adults, but also by older juveniles from previous spawns. Several cichlids, including discus ( Symphysodon spp.), some Amphilophus species, Etroplus , and Uaru species, feed their young with

1782-444: A polyphyletic group includes organisms (e.g., genera, species) arising from multiple ancestral sources. Conversely, the term monophyly , or monophyletic , employs the ancient Greek adjective μόνος ( mónos ) 'alone, only, unique', and refers to the fact that a monophyletic group includes organisms consisting of all the descendants of a unique common ancestor. By comparison, the term paraphyly , or paraphyletic , uses

1881-545: A preference for a floating aquatic plant, duckweed ( Lemna spp.), but also consume some filamentous algae. In Kenya , tilapia were introduced to control mosquitoes , which were causing malaria , because they consume mosquito larvae, consequently reducing the numbers of adult female mosquitoes, the vector of the disease. These benefits are, however, frequently outweighed by the negative aspects of tilapia as invasive species. Tilapia are unable to survive in temperate climates because they require warm water. The pure strain of

1980-442: A remarkably rapid change in coloration, during which a successfully dominant territorial male assumes a more vivid and brighter coloration, while a subordinate or "nonterritorial" male assumes a dull-pale coloration. In addition to color displays, cichlids employ their lateral lines to sense movements of water around their opponents to evaluate the competing male for physical traits/fitness. Male cichlids are very territorial due to

2079-505: A skin secretion from mucous glands. The species Neolamprologus pulcher uses a cooperative breeding system, in which one breeding pair has many helpers that are subordinate to the dominant breeders. Parental care falls into one of four categories: substrate or open brooders, secretive cave brooders (also known as guarding speleophils ), and at least two types of mouthbrooders , ovophile mouthbrooders and larvophile mouthbrooders. Open- or substrate-brooding cichlids lay their eggs in

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2178-464: A special status in systematics as being an observable feature of nature itself and as the basic unit of classification. It is usually implicitly assumed that species are monophyletic (or at least paraphyletic ). However, hybrid speciation arguably leads to polyphyletic species. Hybrid species are a common phenomenon in nature, particularly in plants where polyploidy allows for rapid speciation. Some cladist authors do not consider species to possess

2277-491: A time, attaching them to the spawning surface, which may be a pit constructed on the substrate or another surface. The number of eggs laid was correlated to the space available on the substrate. Once the eggs were attached, the male swam over the eggs and fertilized them. The parents would then dig pits in the sand, 10–20 cm wide and 5–10 cm deep, where larvae were transferred after hatching. Larvae began swimming 8 days after fertilization and parenting behaviors and some of

2376-408: A valid genus while acknowledging its polyphyly. In recent research, the concepts of monophyly, paraphyly, and polyphyly have been used in deducing key genes for barcoding of diverse groups of species. The term polyphyly , or polyphyletic , derives from the two Ancient Greek words πολύς ( polús ) 'many, a lot of', and φῦλον ( phûlon ) 'genus, species', and refers to the fact that

2475-571: A very wide range of conditions. An extreme example is the Salton Sea , where tilapia introduced when the water was merely brackish now live in salt concentrations so high that other marine fish cannot survive. Tilapia are also known to be mouth-brooding species, which means they carry the fertilized eggs and young fish in their mouths for several days after the yolk sac is absorbed. Historically, all tilapia have been included in their namesake genus Tilapia . In recent decades, some were moved into

2574-528: A very wide variety of food items. This is assumed to be one reason why they are so diverse. The features that distinguish them from the other families in the Labroidei include: Kullander (1998) recognizes eight subfamilies of cichlids: the Astronotinae , Cichlasomatinae , Cichlinae , Etroplinae , Geophaginae , Heterochromidinae , Pseudocrenilabrinae , and Retroculinae . A ninth subfamily,

2673-499: A wider variety of foods based on availability. Carnivorous cichlids can be further divided into piscivorous and molluscivorous, since the morphology and hunting behavior differ greatly between the two categories. Piscivorous cichlids eat other fish, fry, larvae, and eggs. Some species eat the offspring of mouthbrooders by head-ramming, wherein the hunter shoves its head into the mouth of a female to expel her young and eat them. Molluscivorous cichlids have several hunting strategies amongst

2772-504: Is a reproductive behavior, many different physiological changes occur in the cichlid while this process is occurring that interfere with social interaction. Different kinds of species that pit spawn, and many different morphological changes occur because of this behavioral experience. Pit spawning is an evolved behavior across the cichlid group. Phylogenetic evidence from cichlids in Lake Tanganyika could be helpful in uncovering

2871-514: Is a specialized snail -eater, while Pungu maclareni feeds on sponges . A number of cichlids feed on other fish, either entirely or in part. Crenicichla species are stealth predators that lunge from concealment at passing small fish, while Rhamphochromis species are open-water pursuit predators that chase down their prey. Paedophagous cichlids such as the Caprichromis species eat other species' eggs or young, in some cases ramming

2970-469: Is also the case for Etroplus maculatus and E. suratensis from India and Sri Lanka. Within the cichlid family, carnivores, herbivores, omnivores, planktivores, and detritivores are known, meaning the Cichlidae encompass essentially the full range of food consumption possible in the animal kingdom. Various species have morphological adaptations for specific food sources, but most cichlids consume

3069-558: Is also used in aquaculture; Nile × blue tilapia hybrids are usually rather dark, but a light-colored hybrid breed known as "Rocky Mountain White" tilapia is often grown due to its very light flesh and tolerance of low temperatures. Commercially grown tilapia are almost exclusively male, typically done by adding male sex hormone in the food to the tilapia fry , causing any potential female tilapia to change sex to male. It can also be achieved through hybridization of certain tilapia species or

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3168-399: Is an assemblage that includes organisms with mixed evolutionary origin but does not include their most recent common ancestor. The term is often applied to groups that share similar features known as homoplasies , which are explained as a result of convergent evolution . The arrangement of the members of a polyphyletic group is called a polyphyly / ˈ p ɒ l ɪ ˌ f aɪ l i / . It

3267-717: Is based on body movements, such as shaking and pelvic fin flicking. In addition, open- and cave-brooding parents assist in finding food resources for their fry. Multiple neotropical cichlid species perform leaf-turning and fin-digging behaviors. Ovophile mouthbrooders incubate their eggs in their mouths as soon as they are laid, and frequently mouthbrood free-swimming fry for several weeks. Examples include many East African Rift lakes ( Lake Malawi , Lake Tanganyika , and Lake Victoria ) endemics, e.g.: Maylandia , Pseudotropheus , Tropheus , and Astatotilapia burtoni , along with some South American cichlids such as Geophagus steindachneri . Larvophile mouthbrooders lay eggs in

3366-544: Is believed to have been a spit-spawning species. Both Madagascar and Indian cichlids retain this feature. However, of the African cichlids, all extant substrate brooding species originate solely from Lake Tanganyika. The ancestor of the Lake Malawi and Lake Victoria cichlids were mouthbrooders. Similarly, only around 30% of South American cichlids are thought to retain the ancestral substrate-brooding trait. Mouthbrooding

3465-427: Is contrasted with monophyly and paraphyly . For example, the biological characteristic of warm-bloodedness evolved separately in the ancestors of mammals and the ancestors of birds; "warm-blooded animals" is therefore a polyphyletic grouping. Other examples of polyphyletic groups are algae , C4 photosynthetic plants , and edentates . Many taxonomists aim to avoid homoplasies in grouping taxa together, with

3564-534: Is equally at home in freshwater marshes and mangrove swamps, and lives and breeds in saltwater environments such as the mangrove belts around barrier islands . Several species of Tilapia , Sarotherodon , and Oreochromis are euryhaline and can disperse along brackish coastlines between rivers. Only a few cichlids, however, inhabit primarily brackish or salt water, most notably Etroplus maculatus , Etroplus suratensis , and Sarotherodon melanotheron . The perhaps most extreme habitats for cichlids are

3663-596: Is thought to have evolved individually up to 14 times, and a return to substrate brooding as many as three separate times between both African and Neotropical species. Cichlids have a great variety of behaviors associated with substrate brooding, including courtship and parental care alongside the brooding and nest-building behaviors needed for pit spawning. Cichlids' behavior typically revolves around establishing and defending territories when not courting, brooding, or raising young. Encounters between males and males or females and females are agonistic, while an encounter between

3762-597: The Cichla species, are valued game fish. The family also includes many popular freshwater aquarium fish kept by hobbyists, including the angelfish , oscars , and discus . Cichlids have the largest number of endangered species among vertebrate families, most in the haplochromine group. Cichlids are particularly well known for having evolved rapidly into many closely related but morphologically diverse species within large lakes, particularly Lakes Tanganyika , Victoria , Malawi , and Edward . Their diversity in

3861-566: The IUCN 's 100 of the World's Worst Alien Invasive Species list. In the United States, tilapia are found in much of the south, especially Florida and Texas , and as far north as Idaho, where they survive in power-plant discharge zones. Tilapia are also currently stocked in the Phoenix, Arizona , canal system as an algal growth-control measure. In a Washington, D.C. fishing report from 21 June 2024, it

3960-435: The Philippines , and Indonesia , are underway in freshwater lakes. In temperate zone localities, tilapiine farming operations require energy to warm the water to tropical temperatures. One method uses waste heat from factories and power stations. At 1.3 million tonnes per annum, China is the largest tilapia producer in the world, followed by Egypt with 0.5 million. The US, by comparison, produces 10 thousand tonnes against

4059-473: The Ptychochrominae , was later recognized by Sparks and Smith. Cichlid taxonomy is still debated, and classification of genera cannot yet be definitively given. A comprehensive system of assigning species to monophyletic genera is still lacking, and there is not complete agreement on what genera should be recognized in this family. As an example of the classification problems, Kullander placed

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4158-974: The Rio Grande in South Texas . Madagascar has its own distinctive species ( Katria , Oxylapia , Paratilapia , Paretroplus , Ptychochromis , and Ptychochromoides ), only distantly related to those on the African mainland. Native cichlids are largely absent in Asia, except for 9 species in Israel , Lebanon , and Syria ( Astatotilapia flaviijosephi , Oreochromis aureus , O. niloticus , Sarotherodon galilaeus , Coptodon zillii , and Tristramella spp.), two in Iran ( Iranocichla ), and three in India and Sri Lanka ( Etroplus and Pseudetroplus ). If disregarding Trinidad and Tobago (where

4257-617: The Tswana word for "fish", or the Greek word "tilon," referring to a fish mentioned by Aristotle, combined with "apios," meaning "distant". Scottish zoologist Andrew Smith named the genus in 1840. The aquaculture of Nile tilapia dates from Ancient Egypt , where it was represented by the hieroglyph K1 , of the Gardiner list : 𓆛. The fish symbolized rebirth in Egyptian art , and

4356-458: The new world , can be classified under the subfamily Cichlinae, while Etroplinae can classify all cichlid species native to the old world . Cichlids are one of the largest vertebrate families in the world. They are most diverse in Africa and South America. Africa alone is host to at least an estimated 1,600 species. Central America and Mexico have about 120 species, as far north as

4455-579: The "true jaws" ( mandibles ) and the " pharyngeal jaws ". This means they are efficient feeders that can capture and process a wide variety of food items. Their mouths are protrusible , usually bordered with wide and often swollen lips. The jaws have conical teeth. Typically, tilapia have a long dorsal fin, and a lateral line that often breaks towards the end of the dorsal fin, and starts again two or three rows of scales below. Some Nile tilapia can grow as long as 60 centimetres (2 ft). Other than their temperature sensitivity, tilapia exist in or can adapt to

4554-651: The African Great Lakes is important for the study of speciation in evolution. Many cichlids introduced into waters outside of their natural range have become nuisances. All cichlids practice some form of parental care for their eggs and fry, usually in the form of guarding the eggs and fry or mouthbrooding . Cichlids span a wide range of body sizes, from species as small as 2.5 cm (1 in) in length (e.g., female Neolamprologus multifasciatus ) to much larger species approaching 1 m (3 ft) in length ( Boulengerochromis and Cichla ). As

4653-535: The African cichlids, can be further split either into Eastern and Western varieties, or into groups depending on which lake the species is from: Lake Malawi , Lake Victoria , or Lake Tanganyika . Of these subgroups, the Madagascar and Indian cichlids are the most basal and least diverse. Of the African cichlids, the West African or Lake Tanganyika cichlids are the most basal. Cichlids' common ancestor

4752-542: The African genus Heterochromis phylogenetically within Neotropical cichlids, although later papers concluded otherwise. Other problems center upon the identity of the putative common ancestor for the Lake Victoria superflock (many closely related species sharing a single habitat), and the ancestral lineages of Lake Tanganyikan cichlids. Phylogeny derived from morphological characters shows differences at

4851-561: The North American sunfishes in morphology, behavior, and ecology. Cichlids share a single key trait - the fusion of the lower pharyngeal bones into a single tooth-bearing structure. A complex set of muscles allows the upper and lower pharyngeal bones to be used as a second set of jaws for processing food, allowing a division of labor between the "true jaws" ( mandibles ) and the " pharyngeal jaws ". Cichlids are efficient and often highly specialized feeders that capture and process

4950-591: The World as the two families in the Cichliformes, part of the subseries Ovalentaria . This family is large, diverse, and widely dispersed. At least 1,650  species have been scientifically described , making it one of the largest vertebrate families. New species are discovered annually, and many species remain undescribed . The actual number of species is therefore unknown, with estimates varying between 2,000 and 3,000. Many cichlids, particularly tilapia , are important food fishes, while others, such as

5049-495: The anal fin (specifically the genital papilla) of the male, which is when he discharges sperm into her mouth and fertilizes the eggs. The genuine color of egg spots is a yellow, red, or orange inner circle with a colorless ring surrounding the shape. Through phylogenetic analysis, using the mitochondrial ND2 gene, the true egg spots are thought to have evolved in the common ancestor of the Astatoreochromis lineage and

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5148-414: The ancient Greek preposition παρά ( pará ) 'beside, near', and refers to the situation in which one or several monophyletic subgroups are left apart from all other descendants of a unique common ancestor. In many schools of taxonomy , the recognition of polyphyletic groups in a classification is discouraged. Monophyletic groups (that is, clades ) are considered by these schools of thought to be

5247-414: The balance between omega-6 and omega-3 fatty acids. Tilapia serve as a natural, biological control for most aquatic plant problems. They consume floating aquatic plants, such as duckweed watermeal ( Lemna spp.), most "undesirable" submerged plants, and most forms of algae. In the United States and countries such as Thailand , they are becoming the plant-control method of choice, reducing or eliminating

5346-537: The basis of fossil evidence, it first appeared in Argentina during the Early Eocene epoch, about 48.6 million years ago; however, molecular clock estimates have placed the family's origin as far back as 67 million years ago, during the late Cretaceous period. The closest living relative of cichlids is probably the convict blenny , and both families are classified in the 5th edition of Fishes of

5445-456: The biparental daffodil cichlid ( Neolamprologus pulcher ), closely related satellite males, those males that surround other males' territories and attempt to mate with female cichlids in the area, help rear the primary males' offspring and their own. A common form of brood care involves food provisioning. For example, females of lyretail cichlids ( Neolamprologus modabu ) dig at sandy substrate more to push nutritional detritus and zooplankton into

5544-510: The blue tilapia, Oreochromis aureus , has the greatest cold tolerance and dies at 7 °C (45 °F), while all other species of tilapia die at a range of 11 to 17 °C (52 to 62 °F). As a result, they cannot invade temperate habitats and disrupt native ecologies in temperate zones; however, they have spread widely beyond their points of introduction in many fresh and brackish tropical and subtropical habitats, often disrupting native species significantly. Because of this, tilapia are on

5643-417: The brackish-water Sarotherodon melanotheron , have attractive patterns and are quite decorative. Tilapia were originally farmed in their native Africa and Levant . Fast-growing, tolerant of stocking density, and adaptable, tilapia have been introduced to and are farmed extensively in many parts of Asia and are increasingly common aquaculture targets elsewhere. Farmed tilapia production in 2002 worldwide

5742-416: The cichlid tribe Haplochromini, exhibit a unique pattern of oval-shaped color dots on their anal fins. These phenomena, known as egg spots, aid in the mouthbrooding mechanisms of cichlids. The egg spots consist of carotenoid-based pigment cells, which indicate a high cost to the organism, when considering that fish are not able to synthesize their own carotenoids. The mimicry of egg spots is used by males for

5841-892: The details, the general basis of the behavior is the same. Mouthbrooding also affects how they choose their mates and breeding grounds. In a 1995 study, Nelson found that in pit-spawning females choose males for mating based on the size of the pit that they dig, as well as some of the physical characteristics seen in the males. Pit spawning also differs from mouth brooding in the size and postnatal care exhibited. Eggs that have been hatched from pit-spawning cichlids are usually smaller than those of mouthbrooders. Pit-spawners' eggs are usually around 2 mm, while mouthbrooders are typically around 7 mm. While different behaviors take place postnatally between mouthbrooders and pit spawners, some similarities exist. Females in both mouthbrooders and pit-spawning cichlids take care of their young after they are hatched. In some cases, both parents exhibit care, but

5940-527: The entire clade and within different communities across separate habitats. Within their phylogeny, many parallel instances are seen of lineages evolving to the same trait and multiple cases of reversion to an ancestral trait. The family Cichlidae arose between 80 and 100 million years ago within the order Perciformes (perch-like fishes). Cichlidae can be split into a few groups based on their geographic location: Madagascar, Indian, African, and Neotropical (or South American). The most famous and diverse group,

6039-466: The evolution of their reproductive behaviors. Several important behaviors are associated with pit spawning, including parental care, food provisioning, and brood guarding. One of the differences studied in African cichlids is reproductive behavior. Some species pit spawn and some are known as mouth brooders. Mouthbrooding is a reproductive technique where the fish scoop up eggs and fry for protection. While this behavior differs from species to species in

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6138-770: The female always cares for the eggs and newly hatched fry. Many species of cichlids use pit spawning, but one of the less commonly studied species that exhibits this behavior is the Neotropical Cichlasoma dimerus . This fish is a substrate breeder that displays biparental care after the fry have hatched from their eggs. One study examined reproductive and social behaviors of this species to see how they accomplished their pit spawning, including different physiological factors such as hormone levels, color changes, and plasma cortisol levels. The entire spawning process could take about 90 minutes and 400~800 eggs could be laid. The female deposits about 10 eggs at

6237-439: The fertilization process. Mouthbrooding females lay eggs and immediately snatch them up with their mouths. Over millions of years, male cichlids have evolved egg spots to initiate the fertilization process more efficiently. When the females are snatching up the eggs into their mouth, the males gyrate their anal fins, which illuminates the egg spots on his tail. Afterwards, the female, believing these are her eggs, places her mouth to

6336-980: The few native cichlids are members of genera that are widespread in the South American mainland), the three species from the genus Nandopsis are the only cichlids from the Antilles in the Caribbean , specifically Cuba and Hispaniola . Europe, Australia, Antarctica, and North America north of the Rio Grande drainage have no native cichlids, although in Florida , Hawaii , Japan, northern Australia, and elsewhere, feral populations of cichlids have become established as exotics . Although most cichlids are found at relatively shallow depths, several exceptions do exist. The deepest known occurrences are Trematocara at more than 300 m (1,000 ft) below

6435-450: The fish, but they make the product unattractive to consumers. Simple quality-control procedures are known to be effective in ensuring the quality of fish entering the market. Tilapia have very low levels of mercury . Tilapia are low in saturated fat , calories, carbohydrates, and sodium, and are a good protein source. They also contain the micronutrients phosphorus , niacin , selenium , vitamin B 12 , and potassium . Tilapia may be

6534-565: The flax, ALA and the two types almost unique to animal sources ( DHA and EPA ), increased in the fish fed this diet. Guided by these findings, tilapia farming techniques could be adjusted to address the nutritional criticisms directed at the fish, while retaining its advantage as an omnivore capable of feeding on economically and environmentally inexpensive vegetable protein. Adequate diets for salmon and other carnivorous fish can alternatively be formulated from protein sources such as soybean , although soy-based diets with soy oil may also change in

6633-401: The full range of parenting behaviours. Secretive cave-spawning cichlids lay their eggs in caves, crevices, holes, or discarded mollusc shells , frequently attaching the eggs to the roof of the chamber. Examples include Pelvicachromis spp., Archocentrus spp., and Apistogramma spp. Free-swimming fry and parents communicate in captivity and in the wild. Frequently, this communication

6732-453: The genus level with phylogeny based on genetic loci . A consensus remains that the Cichlidae as a family are monophyletic. In cichlid taxonomy, dentition was formerly used as a classifying characteristic, but this was complicated because in many cichlids, tooth shapes change with age, due to wear, and cannot be relied upon. Genome sequencing and other technologies transformed cichlid taxonomy. Alternatively, all cichlid species native to

6831-594: The heads of mouthbrooding species to force them to disgorge their young. Among the more unusual feeding strategies are those of Corematodus , Docimodus evelynae , Plecodus , Perissodus , and Genyochromis spp., which feed on scales and fins of other fishes, a behavior known as lepidophagy , along with the death-mimicking behaviour of Nimbochromis and Parachromis species, which lay motionless, luring small fish to their side prior to ambush. This variety of feeding styles has helped cichlids to inhabit similarly varied habitats. Its pharyngeal teeth (in

6930-406: The last common ancestor of species X and Y". On the other hand, polyphyletic groups can be delimited as a conjunction of several clades, for example "the flying vertebrates consist of the bat, bird, and pterosaur clades". From a practical perspective, grouping species monophyletically facilitates prediction far more than does polyphyletic grouping. For example, classifying a newly discovered grass in

7029-602: The modern Haplochrominis species. This ancestor was most likely riverine in origin, based on the most parsimonious representation of habitat type in the cichlid family. The presence of egg spots in a turbid riverine environment would seem particularly beneficial and necessary for intraspecies communication. Two pigmentation genes are found to be associated with egg-spot patterning and color arrangement. These are fhl2-a and fhl2-b , which are paralogs. These genes aid in pattern formation and cell-fate determination in early embryonic development. The highest expression of these genes

7128-490: The monophyletic family Poaceae , the true grasses, immediately results in numerous predictions about its structure and its developmental and reproductive characteristics, that are synapomorphies of this family. In contrast, Linnaeus' assignment of plants with two stamens to the polyphyletic class Diandria, while practical for identification, turns out to be useless for prediction, since the presence of exactly two stamens has developed convergently in many groups. Species have

7227-565: The narrative in the Gospel of Matthew about the apostle Peter catching a fish that carried a coin in its mouth . Though the passage does not name the fish, different tilapia species ( Sarotherodon galilaeus , Oreochromis aureus , Coptodon zillii , and Tristramella ) are found in the Sea of Galilee, where the author of the Gospel of Matthew recounts the event took place. These species have been

7326-403: The only valid groupings of organisms because they are diagnosed ("defined", in common parlance) on the basis of synapomorphies , while paraphyletic or polyphyletic groups are not. From the perspective of ancestry, clades are simple to define in purely phylogenetic terms without reference to clades previously introduced: a node-based clade definition , for example, could be "All descendants of

7425-733: The open or in a cave and take the hatched larvae into the mouth. Examples include some variants of Geophagus altifrons , and some Aequidens , Gymnogeophagus , and Satanoperca , as well as Oreochromis mossambicus and Oreochromis niloticus . Mouthbrooders, whether of eggs or larvae, are predominantly females. Exceptions that also involve the males include eretmodine cichlids (genera Spathodus , Eretmodus , and Tanganicodus ), some Sarotherodon species (such as Sarotherodon melanotheron ), Chromidotilapia guentheri , and some Aequidens species. This method appears to have evolved independently in several groups of African cichlids. Polyphyletic A polyphyletic group

7524-436: The open, on rocks, leaves, or logs. Examples of open-brooding cichlids include Pterophyllum and Symphysodon species and Anomalochromis thomasi . Male and female parents usually engage in differing brooding roles. Most commonly, the male patrols the pair's territory and repels intruders, while the female fans water over the eggs, removing the infertile ones, and leading the fry while foraging. Both sexes are able to perform

7623-814: The physical aggression of males becomes a contest for resources (mates, territory, food). Female cichlids prefer to mate with a successfully alpha male with vivid coloration, whose territory has food readily available. Cichlids mate either monogamously or polygamously . The mating system of a given cichlid species is not consistently associated with its brooding system. For example, although most monogamous cichlids are not mouthbrooders, Chromidotilapia , Gymnogeophagus , Spathodus , and Tanganicodus all include – or consist entirely of – monogamous mouthbrooders. In contrast, numerous open- or cave-spawning cichlids are polygamous; examples include many Apistogramma , Lamprologus , Nannacara , and Pelvicachromis species. Most adult male cichlids, specifically in

7722-409: The physiological factors measured changed. In the same study, color changes were present before and after the pit spawning occurred. For example, after the larvae were transferred and the pits were beginning to be protected, their fins turned a dark grey color. In another study, of the rainbow cichlid, Herotilapia multispinosa , color changes occurred throughout the spawning process. Before spawning,

7821-648: The precise sister relationships predicted by vicariance : Africa-South America and India-Madagascar. The dispersal hypothesis, in contrast, requires cichlids to have negotiated thousands of kilometers of open ocean between India and Madagascar without colonizing any other island, or for that matter, crossing the Mozambique Channel to Africa. Although the vast majority of Malagasy cichlids are entirely restricted to fresh water, Ptychochromis grandidieri and Paretroplus polyactis are commonly found in coastal brackish water and are apparently salt tolerant, as

7920-539: The preferred "aquatic chickens" of the trade. Because of their large size, rapid growth, and palatability, tilapia cichlids are the focus of major farming efforts, specifically various species of Oreochromis , Sarotherodon , and Coptodon (all were formerly in the namesake genus Tilapia ). Like other large fish, they are a good source of protein and popular among artisanal and commercial fisheries . Most such fisheries were originally found in Africa, but outdoor fish farms in tropical countries, such as Papua New Guinea ,

8019-421: The pressure of reproduction, and establish their territory and social status by physically driving out challenging males (novel intruders) through lateral displays (parallel orientation, uncovering gills), biting, or mouth fights (head-on collisions of open mouths, measuring jaw sizes, and biting each other's jaws). The cichlid social dichotomy is composed of a single dominant with multiple subordinates, where

8118-431: The productive output of both. Arkansas stocks many public ponds and lakes to help with vegetation control, favoring tilapia as a robust forage species and for anglers. In Kenya, tilapia help control mosquitoes , which carry malaria parasites. They consume mosquito larvae , which reduces the numbers of adult females, the disease's vector . In Brazil , Nile tilapia ( Oreochromis niloticus ) fish skin applied as

8217-669: The question of desirability of Tilapia culture in other parts of India. Whole tilapia fish can be processed into skinless, boneless fillets. In some of the commercial strains, the yield has been reported up to 47% at harvest weight. Tilapia are among the commercially important aquaculture species that are susceptible to off-flavors (others include trout, barramundi , and channel catfish ). These 'muddy' or 'musty' flavors are normally caused by geosmin and 2-methylisoborneol , organic products of ubiquitous cyanobacteria that are often present or bloom sporadically in water bodies and soil. These flavors are no indication of freshness or safety of

8316-404: The rainbow cichlid was an olive color with grey bands. Once spawning behaviors started, the body and fins of the fish became a more golden color. When the eggs were finished being laid, the pelvic fin all the way back to the caudal fin turned to a darker color and blackened in both the males and the females. Females prefer a bigger pit size when choosing where to lay eggs. Differences are seen in

8415-408: The sizes of pits that created, as well as a change in the morphology of the pits. Evolutionary differences between species of fish may cause them to either create pits or castles when spawning. The differences were changes in the way that each species fed, their macrohabitats, and the abilities of their sensory systems. Cichlids are renowned for their recent, rapid evolutionary radiation, both across

8514-678: The state in the 1950s as a cheap protein source, quickly spread across the state’s freshwater bodies because of its ability to thrive in polluted, low-oxygen environments. The Fisheries Research Committee has recommended the culture of this fish only in areas in the western slopes of the Western Ghats and the coastal strip between Cape Comorin and south of and excluding river Tapti, and in districts of Tinnevellv, Madurai and Ramnad in Madras south of and including river Vaigai. The Committee has suggested further investigation to enable it to examine

8613-704: The surface in Lake Tanganyika . Others found in relatively deep waters include species such as Alticorpus macrocleithrum and Pallidochromis tokolosh down to 150 m (500 ft) below the surface in Lake Malawi, and the whitish (non pigmented ) and blind Lamprologus lethops , which is believed to live as deep as 160 m (520 ft) below the surface in the Congo River . Cichlids are less commonly found in brackish and saltwater habitats, though many species tolerate brackish water for extended periods; Mayaheros urophthalmus , for example,

8712-775: The surrounding water. Adult of N. modabu perform this strategy to collect food for themselves, but dig more when offspring are present, likely to feed their fry. This substrate-disruption strategy is rather common and can also be seen in convict cichlids ( Cichlasoma nigrofasciatum ). Other cichlids have an ectothermal mucus that they grow and feed to their young, while still others chew and distribute caught food to offspring. These strategies, however, are less common in pit-spawning cichlids. Cichlids have highly organized breeding activities. All species show some form of parental care for both eggs and larvae , often nurturing free-swimming young until they are weeks or months old. Communal parental care, where multiple monogamous pairs care for

8811-421: The target of small-scale artisanal fisheries in the area for thousands of years. Tilapia typically have laterally compressed, deep bodies. Like other cichlids, their lower pharyngeal bones are fused into a single tooth-bearing structure. A complex set of muscles allows the upper and lower pharyngeal bones to be used as a second set of jaws for processing food (cf. morays ), allowing a division of labor between

8910-406: The throat) afford cichlids so many "niche" feeding strategies, because the jaws pick and hold food, while the pharyngeal teeth crush the prey. Aggressive behavior in cichlids is ritualized and consists of multiple displays used to seek confrontation while being involved in evaluation of competitors, coinciding with temporal proximity to mating. Displays of ritualized aggression in cichlids include

9009-662: The tilapia in its [true] nature guiding the speedy boat in its waters." Tilapia were one of the three main types of fish caught in Talmudic times from the Sea of Galilee , specifically the Galilean comb ( Sarotherodon galilaeus ). Today, in Modern Hebrew, the fish species is called amnoon (probably a compound of am , "mother" and noon , "fish"). In English, it is sometimes known by the name "St. Peter's fish", which comes from

9108-445: The use of so-called "supermales" that have homozygous male sex chromosomes (resulting in all their offspring receiving a male sex chromosome and thus becoming males). Males are preferred because they grow much faster than females. Additionally, because tilapia are prolific breeders, the presence of female tilapia results in rapidly increasing populations of small fish, rather than a stable population of harvest-size animals. Tilapia, as

9207-435: The use of toxic chemicals and heavy metal-based algaecides. However, their environmental impact as an invasive species may outweigh their ecological benefit. Their tolerance for a wide range of environmental conditions allow them to thrive in polluted or otherwise degraded aquatic habitats. They are used for zoo ponds as a source of food for birds. Tilapia can be farmed with shrimp in a symbiotic manner, positively enhancing

9306-478: The varieties within the group. Lake Malawi cichlids consume substrate and filter it out through their gill rakers to eat the mollusks that were in the substrate. Gill rakers are finger-like structures that line the gills of some fish to catch any food that might escape through their gills. Many cichlids are primarily herbivores , feeding on algae (e.g. Petrochromis ) and plants (e.g. Etroplus suratensis ). Small animals, particularly invertebrates , are only

9405-492: The warm hypersaline lakes where the members of the genera Alcolapia and Danakilia are found. Lake Abaeded in Eritrea encompasses the entire distribution of D. dinicolai , and its temperature ranges from 29 to 45 °C (84 to 113 °F). With the exception of the species from Cuba, Hispaniola, and Madagascar, cichlids have not reached any oceanic island and have a predominantly Gondwanan distribution, showing

9504-426: Was about 1.5 million tonnes (1.7 million short tons) annually, with an estimated value of US$ 1.8 billion, about equal to those of salmon and trout . Unlike carnivorous fish, tilapia can feed on algae or any plant-based food. This reduces the cost of tilapia farming, reduces fishing pressure on prey species, avoids concentrating toxins that accumulate at higher levels of the food chain , and makes tilapia

9603-585: Was associated in Egyptian belief-systems with Hathor , goddess of fertility and abundance. The tilapia was also said to accompany and protect the sun god on his daily journey across the sky, and a tilapia painted on tomb walls may recall part of spell 15 of the Book of the Dead by which the deceased hopes to take his place in the sun boat: "You see the tilapia in its [true] form at the turquoise pool", and "I behold

9702-674: Was reported that an angler caught a Tilapia on a crankbait at the Jones Point Park under the Woodrow Wilson Bridge , which is on the Potomac River . Many state fish and wildlife agencies in the United States, Australia, South Africa, and elsewhere consider them to be invasive species . Larger tilapia species are generally poor community aquarium fish because they eat plants, dig up the bottom, and fight with other fish. The larger species are often raised as

9801-520: Was temporally correlated with egg-spot formation. A short, interspersed, repetitive element was also seen to be associated with egg spots. Specifically, it was evident upstream of the transcriptional start site of fhl2 in only Haplochrominis species with egg spots The cichlid Benitochromis nigrodorsalis from Western Africa ordinarily undergoes biparental reproduction, but is also able to undergo facultative (optional) selfing ( self-fertilization ). Facultative selfing may be an adaptive option when

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