Gold Fish Body Part

Gold Fish Body Part

Credits to: Solid Gold Aquatics

Betta Fighting Fish Body Part

Source: japanesefightingfish.org

Flowerhorn Fish

Flowerhorn cichlids are ornamental aquarium fish noted for their vivid colors and the distinctively shaped heads for which they are named. Their head protuberance, or kok, is formally termed a nuchal hump. Like blood parrot cichlids, they are man-made hybrids that exist in the wild only because of their release. Flowerhorns first emerged for sale on the aquarium market in Malaysia in the late 1990s and soon became popular in many countries in Asia. First developed in Malaysia, Thailand, and Taiwan, they became very popular with Asian fish hobbyists. They are also kept by hobbyists in the US,India and Europe. Numerous cast-off flowerhorns have been released to the wild, especially in Singapore and Malaysia, where they have become an invasive pest animal. Their importation is banned in Australia.

Golden Base type flowerhorn

Origin

Flowerhorn breeding dates to 1993.^{[1][unreliable source]} Taiwanese and Malaysians admired fish with protruding heads, known as 'kaloi' or 'warships', found in the western part of the nation. The slightly protruding forehead and long tail of these fish were prized in Taiwanese society as bringing luck in geomancy. By 1994, red devil cichlids (typically Amphilophus labiatus) and trimac cichlids (Amphilophus trimaculatus) had been imported from Central America to Malaysia and the hybrid blood parrot cichlid had been imported from Taiwan to Malaysia. These fish were then bred together, marking the birth of the flowerhorn.^{[dubious – discuss]}

In 1995, the blood parrots were further crossbred with the Human Face Red God of Fortune, which produced a new breed called the Five-colors God of Fortune. With its beautiful colors, this fish quickly became popular. Selective breeding continued through 1998, when the Seven-colors Blue Fiery Mouth (also known as Greenish Gold Tiger) was imported from Central America, and crossbred with the Jin Gang Blood Parrot from Taiwan.^{[1][unreliable source]} This crossbreeding led to the first generation of hua luo han flowerhorn hybrids (often generically called luohans in English), which were then followed by subsequent flowerhorn introductions.

Arrival in the WestEdit

Learn more Some of this section's listed sources may not be reliable.

When luohans were first imported to the United States, there were only two varieties of these fish for distribution, flowerhorn and golden base.^[1] Flowerhorns came in two varieties, those with pearls (silver-white spots on the skin) and those without. Golden bases also had two varieties, those that faded and those that did not. Among the flowerhorns, the ones without pearls were quickly overtaken in popularity by those with pearls, becoming pearl-scale flowerhorns, which were developed into the Zhen Zhu variety. Within the golden bases, the unfaded ones developed an attractive golden skin in place of what had been the flowerhorn's grey skin.

By 1999, there were four varieties of flowerhorn available in the American market: regular flowerhorns, pearl-scale flowerhorns, golden flowerhorns, and faders.^[1] Commercial breeders proliferated, and fish were selected for appearance with little regard for terminology.^[1] Consequently, names became confusing and parentage became difficult to track.

Around 2000 to 2001, the Kamfa variety appeared. These were hybrids of any type of flowerhorn crossed with any species of the genus Vieja or with any parrot cichlid.^[1] These brought in some new traits, such as short mouths, wrapped tails, sunken eyes, and increasingly larger head bumps. Seeing this, those who bred the Zhen Zhus began line breeding their fish to develop faster and become more colorful, in order to compete with the Kamfa strains.^[1]

In captivity

Flowerhorn cichlids have a lifespan of 10–12 years. They are usually kept at a water temperature of 80–85 °F, and a pH of 7.4–8.0. They require a tank of a minimum of 40 gallons, with 75 gallons optimal. A breeding pair may require a tank of 150 gallons or more, depending on size. Being aggressive and territorial, two or more flowerhorns are usually not kept together, but the tank housing them can be divided up with acrylic dividers or egg crates.

There are several ways by which breeders distinguish between male and female flowerhorns. Generally, the males are larger than the females, but there are some exceptions. Males have the kok, or the nuchal hump, on their foreheads. Males also usually have brighter and more vivid colors. For most breeds, the females have black dots on their dorsal fins, whereas males usually have longer anal and dorsal fins. Females tend to have an orange belly, especially when ready to breed. The mouth of the male is thicker and more pronounced than the female's. One sure way to determine the sex of flowerhorn is that grown female will lay eggs every month even without the male.^{[2][self-published source?]}

Flowerhorn cichlids are subject to several diseases, including hole-in-head disease, "ich", and digestive blockages.

Varieties

General flowerhorn variety classification, containing several subsets of varieties (strains) from different countries and breeders.

The original flowerhorn hybrid stock are referred to as luohans (from the Chinese word for the Buddhist concept of arhat). The four main derived varieties are Zhen Zhu, Golden Monkey, Kamfa, and the golden base group,^[1] which includes Faders and the Golden Trimac. They are sometimes referred to as breeds, though that term technically only refers to varieties of fully domesticated species.

King Kong Parrots and Red IngotsEdit

Blood parrot cichlids were the earliest defined type of cichlid hybrid, whereas the King Kong Parrot represents an early stage in the transition to flowerhorn breeding. The blood parrots are smaller, with a bigger head, more protruding eyes, and a V-shaped mouth. The King Kong Parrot is longer, with a reddish orange color, and a dorsal fin shorter than the anal fin. The shape of the King Kong is similar to the red devil cichlid, and, when it reaches a size of 18 cm, the shape of the mouth changes to a triangle with a more protruding jaw. Only 20% of these fish grow to a size of a half kilogram.^[1]

King Kong Parrots are sometimes colored purple or blue by pigment injection. This practice is unhealthy for the fish, and the color will fade with time.^[1] Parrot cichlids fed with natural colorants and attractants naturally develop a red color. With further breeding, a round body shape has been selected, with the dorsal fin and anal fin longer than the tail fin, and the mouth can open and close naturally. These fish have clear eyes, and 90% of them grow to 1 kg or above, with the characteristic flowerhorn head shape.^[1]

The Red Mommon and Red Ingot varieties are the most typical of these hybrid cichlids. Both of these fishes are appreciated for feng shui.^[3] The Red Mommon is named for its high forehead, which looks like the hat worn by the God of Fortune. The Red Ingot is named for its yuan-bao shape, referring to odd-shaped gold or silver pieces formerly used as money in China.^[1]

The Red Mommon and Red Ingot grow faster in the first year, with a size of about 20 cm. They grow to 25–28 cm by two years later. Their maximum size is not yet known, and it is believed that the fish may grow to 30 cm or above in the future. Both of these fish are raised at 28 °C water temperature, pH ~6–8 (with slightly acid water preferred), and kH ~3–6, while avoiding any sudden change in water quality. It is also common to test regularly for ammonia and nitrite. Both of these fishes can be bred with different kinds of cichlids.^[1]

Golden MonkeyEdit

Golden Monkey

The genuine Golden Monkey (also called Good Fortune) or Kamalau was bred by Lam Seah and Lam Soon in Bercham, Ipoh, Malaysia. After the third generation, all of them were sold to the A-1 Aquarium in 2001. This type of flowerhorn is an original luohan-based fish and not a mixed-type Zen Zhu or Kamfa.^[1]

It can be a particularly expensive flowerhorn, carrying a price tag of more than one thousand dollars. The most expensive Golden Monkey was sold for $600,000 dollars during a Malaysian exhibition in 2009.

KamfaEdit

Kamfa

This variety originated directly from the luohan. Its main characteristics are white or yellow eyes (red eyes are possible but not common), a fan tail, a water-colored head bump, sunken eyes, and smaller lips than the Zhen Zhu. This variety generally also has a larger and more square body than that of the Zhen Zhu. Head flowers can be found on the Kamfa, but not as prominently as with Zhen Zhus.

Zhen ZhuEdit

This variety originated slightly after the Kamfa, derived from the luohan. It has a rounded tail, large mouth, red protruding eyes, and a prominent head flower. Zhen Zhu means 'pearl flowerhorn'. This variety's strongest characteristic is pearling. Breeders often cross other types with Zhen Zhus because they breed easily and can create better pearling (flowerline) for the next generation. Weak tails can also carry over, however.^[1]

Golden baseEdit

Golden Base

Golden base is a group of multiple varieties, including Faders and Golden Trimac.^[1] Faders are called by that name because during the juvenile period of life they first lose their color and go completely black then, as the fading process continues, the black fades away, leaving a more vibrant color, usually yellow or red.

Red Texas cichlids are related to the golden base family of flowerhorns. They were originally created by breeding a green Texas cichlid with a Mommon or King Kong parrot, then crossing the offspring back to the parents until a consistent red color was achieved. Hobbyists consider the most important feature of the red Texas to be the color. Red Texas cichlids range in colors, and are rated as:

• Unfaded: lowest grade of red Texas.
• Yellow: second lowest grade.
• Orange: the majority of red Texas fall into this category.
• Coral: pinkish but not quite full red.
• Red: most desirable color.

The second characteristic that sets the red Texas apart is the pearling. Red Texas can vary greatly in terms of the type of pearling.^[1]

King KamfaEdit

King Kamfa

From the Kamfa family, these Flowerhorns are known for their massive nuchal humps, also called a kok, and their strikingly varied patterning. This fish typically has white or yellow sunken eyes, although red eyes are possible but rare. Distinctive features of this strain include an intense black double flower row along the lateral line, and very thick white pearling. Originating in Thailand, this strain has seen a recent rebirth in Vietnam. The body is typical of a Kamfa, with a fan tail, and a longer body than some other Kamfas.^[1] King Kamfa is the most expensive flowerhorn strain.^{[citation needed]}

KamfamalauEdit

Kamfamalau

This is a cross of a Kamfa male and a Malau female. The body and face resemble a typical Kamfa (see above). The finnage and sunken eyes reflect the Kamfa genes. The main feature of a Kamfamalau is the pearling. Fins typically take on a "frosted" pearl look that is rarely found in any other varieties of flowerhorn. Pearling usually crosses all the way across the head bump, another rarity in flowerhorn varieties. This strain should display the best characteristics of both Kamfa and Malau.^[1]

Thai SilkEdit

The Thai Silk, also known as Titanium, is a relatively new strain which is almost completely metallic blue, gold, or white. Its origins are unclear. A new strain of Thai silk has been developed more square body shape like a Kamfa but their eyes can be red, yellow and white. It was believed to be a cross between White Tigers (Texas lineage), pure Texas cichlid and a Vieja.

Strains

A strain is a more specific subset within a particular variety. Strains can get as narrowly defined as all coming from one individual parent fish. Strains can also differ by country of origin and by breeder.

JPG or Golden AppleEdit

Created by Ah Soon of Malaysia, these fish are characterized by a large stocky body, as well as metallic pearling.^[1]

IndoMalauEdit

Elvis strain

These were created by the Indonesian Luohan Club (ILC), using a Golden Monkey (or Malau) female and a Zhen Zhu male. The second generation was spawned from the Elvis selection and a Golden Monkey female. The strain is characterized by extensive pearling all over the body, face, and head. What distinguishes an IndoMalau's pearls from that of a Zhen Zhu or a King Kamfa is that they are extremely fine. As the fish ages, the pearls become more intricately woven and thinner. Flowerlines vary dramatically; some only have a few flower spots. Most ILC IndoMalaus will include some singular flowers on the back line or "top row". The front half of the fish, from the pectoral fins forwards, is red. The back half is a golden gradient intensifying in color towards the tail. The body is very wide and high, a throwback to the original luohan. There is a very pronounced chin or "gobbler". The head is usually forward-protruding. The tail is fan-shaped, close to that of a Kamfa. The dorsal and anal fins lack trailers, a common trait found also in Zhen Zhu. The caudal peduncle is very large and pronounced in this strain.^[1]

Tan King strain

Tan KingEdit

This strain was created by a Mr. Tan of Vietnam, by crossing a Zhen Zhu with a Kamfa. It has pearls and a flowerline like a King Kamfa, but the body and fins are more closely related to the Zhen Zhu. Most have protruding eyes and a more rounded tail like a Zhen Zhu.^[1]

Strains developed in the United StatesEdit

New flowerhorn strains have been developed through breeding programs in the United States. Although it is hard for the US to compete with Asia's well established flowerhorn breeding farms, strains with unique genetics have been created.

Gallery of early flowerhorn strains

• 

  Coronation Link

 
• 

  Tornado Effect

 
• 

  Perfect Harmony

 
• 

  Unique Track

 
• 

  Absolute Wonder

 
• 

  Ancient Warship

 
• 

  Creative Measure

 
• 

  Exotic Marvel

 
• 

  Legacy

 
• 

  Living Legend

 
• 

  Pacific Miracle

 
• 

  Quantum Grace

 
• 

  Rising Rainbow

 
• 

  Royal Degree

 
• 

  Scarlet Passion

Guppy Fish

The guppy (Poecilia reticulata), also known as millionfish and rainbow fish,^[2] is one of the world's most widely distributed tropical fish and one of the most popular freshwater aquarium fish species. It is a member of the family Poeciliidae and, like almost all American members of the family, is live-bearing.^[3] Guppies originate from northeast South America, but have been introduced to many environments and are now found all over the world. They are highly adaptable and thrive in many different environmental and ecological conditions.^[4] Male guppies, which are smaller than females, have ornamental caudal and dorsal fins. Wild guppies generally feed on a variety of food sources, including benthic algae and aquatic insect larvae.^[5] Guppies are used as a model organism in the fields of ecology, evolution, and behavioural studies.^[4]

Guppy
Wild male and female guppies
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Cyprinodontiformes
Family:	Poeciliidae
Genus:	Poecilia
Species:	P. reticulata
Binomial name
Poecilia reticulata W. Peters, 1859
Distribution map for Poecilia reticulata
Synonyms[1]
Acanthocephalus guppii (Günther, 1866) Acanthophacelus reticulatus (W. Peters, 1859) Girardinus guppii Günther, 1866 Girardinus reticulatus (W. Peters, 1859) Lebistes poecilioides De Filippi, 1861 Lebistes reticulatus (W. Peters, 1859) Poecilioides reticulatus (W. Peters, 1859)

Taxonomy

Guppies were first described in Venezuela as Poecilia reticulata by Wilhelm Peters in 1859 and as Lebistes poecilioides in Barbados by De Filippi in 1861. It was named Girardinus guppii by Albert Günther in honor of Robert John Lechmere Guppy, who sent specimens of the species from Trinidad to the Natural History Museum in London.^[6] It was reclassified as Lebistes reticulatus by Regan in 1913. Then in 1963, Rosen and Bailey brought it back to its original name, Poecilia reticulata. While the taxonomy of the species was frequently changed and resulted in many synonyms, "guppy" remains the common name even as Girardinus guppii is now considered a junior synonym of Poecilia reticulata.^[4]

Distribution and habitat

Guppies are native to Antigua and Barbuda, Barbados, Brazil, Guyana, Jamaica, the Netherlands Antilles, Trinidad and Tobago, the U.S. Virgin Islands, and Venezuela.^[7][8] However, guppies have been introduced to many different countries on every continent except Antarctica. Sometimes this has occurred accidentally, but most often as a means of mosquito control. The guppies were expected to eat the mosquito larvae and help slow the spread of malaria, but in many cases, these guppies have had a negative impact on native fish populations.^[9] Field studies reveal that guppies have colonized almost every freshwater body accessible to them in their natural ranges, especially in the streams located near the coastal fringes of mainland South America. Although not typically found there, guppies also have tolerance to brackish water and have colonized some brackish environments.^[4] They tend to be more abundant in smaller streams and pools than in large, deep, or fast-flowing rivers.^[10] They also are capable of being acclimated to full saltwater as well as being used to cycle saltwater aquariums like their molly cousins

Description

Guppies exhibit sexual dimorphism. While wild-type females are grey in body color, males have splashes, spots, or stripes that can be any of a wide variety of colors.^[11] The size of guppies vary, but males are typically 1.5–3.5 cm (0.6–1.4 in) long, while females are 3–6 cm (1.2–2.4 in) long.

A variety of guppy strains are produced by breeders through selective breeding, characterized by different colours, patterns, shapes, and sizes of fins, such as snakeskin and grass varieties. Many domestic strains have morphological traits that are very distinct from the wild-type antecedents. Males and females of many domestic strains usually have larger body size and are much more lavishly ornamented than their wild-type antecedents.^[12]

Guppies have 23 pairs of chromosomes, including one pair of sex chromosomes, the same number as humans.^[13] The genes responsible for male guppies' ornamentations are Y-chromosome linked and are heritable.^[14

Lifecycle

Two or three generations of guppies per year occur in the wild. Guppies are well developed and capable of independent existence without further parental care by the time they are born. Young guppies school together and perform antipredator tactics. Brood size is extremely variable, yet some consistent differences exist among populations depending on the predation level and other factors.^[4] Females of matching body sizes tend to produce more numerous but smaller-sized offspring in high-predation conditions. Female guppies first produce offspring at 10–20 weeks of age, and they continue to reproduce until 20–34 months of age. Male guppies mature in 7 weeks or less.^[4] Total lifespan of guppies in the wild varies greatly, but it is typically around 2 years.^[15] Variations in such life historic characteristics of guppies are observed in different populations, indicating that different evolutionary pressures exist.

MaturityEdit

Guppies' body sizes are positively correlated with age, and their size at maturation varies highly depending on the predation risk of the occupied environments. Male and female guppies from high-predation regions mature faster and start reproducing earlier, and they devote more resources to reproduction than those from low-predation regions.^[16] Females from high-predation regions reproduce more frequently and produce more offspring per litter, indicating that they are more fecund than low-predation females. Female guppies' reproductive success is also related to age. Older females produce offspring with reduced size and at increased interbrood intervals.^[17]

SenescenceEdit

One major factor that affects wild guppies' senescence patterns is the mortality rate caused by predation. Guppies from high-predation environments suffer high extrinsic mortality rate because they are more likely to be killed by predators. Female guppies from high-predation environments experience a significant increase in mortality at 6 months of age, while those from low-predation environments do not suffer increased mortality until 16 months. However, guppies from high-predation environments were found to have longer lifespans because their reproductive lifespans are longer. No significant difference is seen in postreproductive lifespans.^{[15][dubious – discuss]}

Population regulationsEdit

In addition to senescence pattern, resource availability and density also matter in regulation of guppy populations. Guppies reduce their fecundity and reproductive allocation in response to scarce food. When food is abundant, they increase brood size.^[18] Differential reproductive allocation can be the cause of seasonality of life-history characteristics in some guppy populations. For example, during the wet season from May to December, guppies in the Northern Range of Trinidad reduce their investment in reproduction regardless of predation level, possibly in response to decreased food resources.^[19] Population density also matters in simpler environments because higher intraspecific competition causes a decrease in reproductive rate and somatic growth rate, and a corresponding increase in juvenile mortality rate due to cannibalism.^[20] It was confirmed that in low-predation environments, guppy populations are in part regulated by density.^[21]

Ecology and behavior

MatingEdit

Female and male adults of an ornamental strain

Guppies have the mating system called polyandry, where females mate with multiple males.^[22] Multiple mating is beneficial for males because the males' reproductive success is directly related to how many times they mate. The cost of multiple mating for males is very low because they do not provide material benefit to the females or parental care to the offspring. Conversely, multiple mating can be disadvantageous for females because it reduces foraging efficiency and increases the chances of predation and parasitic infection.^[23] However, females gain some potential benefits from multiple mating. For example, females that mate multiply are found to be able to produce more offspring in shorter gestation time, and their offspring tend to have better qualities such as enhanced schooling and predator evasion abilities.^[23]

Female guppies mate again more actively and delay the development of a brood when the anticipated second mate is more attractive than the first male. Experiments show that remating females prefer a novel male to the original male or a brother of the original male with similar phenotypes. Females' preference for novel males in remating can explain the excessive phenotypic polymorphism in male guppies.^[24]

Inbreeding avoidanceEdit

Inbreeding ordinarily has negative fitness consequences (inbreeding depression), and as a result species have evolved mechanisms to avoid inbreeding. Inbreeding depression is considered to be due largely to the expression of homozygous deleterious recessive mutations.^[25] Numerous inbreeding avoidance mechanisms operating prior to mating have been described. However, inbreeding avoidance mechanisms that operate subsequent to copulation are less well known. In guppies, a post-copulatory mechanism of inbreeding avoidance occurs based on competition between sperm of rival males for achieving fertilization.^[26] In competitions between sperm from an unrelated male and from a full sibling male, a significant bias in paternity towards the unrelated male was observed.^[26]

Females' mating choiceEdit

Female guppy choice plays an important role in multiple mating. Female guppies are attracted to brightly colored males, especially ones with orange spots on the flank.^[27] Orange spots can serve as an indicator of better physical fitness, as orange-spotted males are observed to swim longer in a strong current.^[28] There is also the concept of color association to possibly explain mate choice since one of the food sources wild guppies compete vigorously for is the fruit of cabrehash trees (Sloanea laurifolia), an orange carotenoid-containing fruit.^[29] The orange coloration that female guppies select for in males is composed of carotenoids, the saturation of which is affected by the male's carotenoid ingestion and parasite load.^[30] Guppies cannot synthesize these pigments by themselves and must obtain them through their diet. Because of this connection, females are possibly selecting for healthy males with superior foraging abilities by choosing mates with bright orange carotinoid pigments, thus increasing the survival chance of her offspring.^[30] Due to the advantage in mating, male guppies evolve to have more ornamentation across generations in low-predation environments where the cost of being conspicuous is lower. The rate and duration of courtship display of male guppies also play an important role in female guppies' mating choice. Courtship behavior is another indicator of fitness due to the physical strength involved in maintaining the courtship dance, called sigmoid display, in which the males flex their bodies into an S shape and vibrate rapidly.^[31]

Female mating choice may also be influenced by another female's choice. In an experiment, female guppies watched two males, one solitary and the other actively courting another female, and were given a choice between the two. Most females spent a longer time next to the male that was courting.^[32] Female guppies' preference for fit males allows their descendants to inherit better physical fitness and better chance of survival.

PredationEdit

Aequidens pulcher, a common predator of guppies

Guppies have many predators, such as larger fish and birds, in their native range. Some of their common predators in the wild are Crenicichla alta, Anablepsoides hartii, and Aequidens pulcher.^[33] Guppies' small bodies and the bright coloration of males make them easy prey, and like many fish, they often school together to avoid predation. Schooling is more favored by evolution in populations of guppies under high predation pressure, exerted either by predator type or predator density.^[34] Coloration of guppies also evolves differentially in response to predation. Male guppies that are brighter in color have an advantage in mating as they attract more females in general, but they have a higher risk of being noticed by predators than duller males. Male guppies evolve to be more dull in color and have fewer, smaller spots under intense predation both in wild and in laboratory settings.^[35] Female guppies in a high-predation environment also evolve to prefer brightly colored males less, often rejecting them.^[36]

Predator inspectionEdit

When guppies encounter a potential predator, some of them approach the predator to assess danger. This behavior, called predator inspection, benefits the inspector since it gains information, but puts the inspector at a risk of predation. To reduce the risk, inspectors avoid the predator's mouth area—called the 'attack cone'—and approach the predator from the side or back. They may also form a group for protection, the size of which is larger in high-predation populations. Although evidence indicates predators are less likely to attack an inspector than a non-inspector, the inspectors remain at higher risk due to proximity to the predator.^[37]

Risk-taking behaviors such as predator inspection can be evolutionarily stable only when a mechanism prevents selfish individuals from taking advantage of "altruistic" individuals. Guppies may adopt a conditional-approach strategy that resembles tit for tat. According to this hypothesis, guppies would inspect the predator on the first move, but if their co-inspectors do not participate in the predator inspection visits or do not approach the predator close enough, they can retaliate at the trailers by copying the trailer's last move in the next predator inspection visit. The hypothesis was supported in laboratory experiments.^[38]

Predator diversionEdit

When guppies detect a predator, their irises rapidly darken from silver to jet black, which draws predators to attack the guppies' head instead of their body's center of mass. ^[39][40] Perhaps counterintuitively, this predator divertive behavior allows guppies to rapidly pivot out of the way as predators lunge where the guppies' head was; this "matador-like" anti-predator behavior was first described in guppies but may be found in other animal species with bright, attention-grabbing coloration located on vital organs, such as epaulette sharks.^[41][42]

ParasitesEdit

Guppies are also host to a range of parasites and one of these, Gyrodactylus turnbulli, has been used as a model system for studying host-parasite interactions.^[43] Recent work on this has shown that the interaction between exposure to chronic anthropogenic noise and G. turnbulli can decrease guppy survival. While a short burst of underwater noise has positive effects on parasite densities on the host. Most likely resulting in negative fitness effects for guppies.^[43]

FeedingEdit

Wild guppies feed on algal remains, diatoms, invertebrates, plant fragments, mineral particles, aquatic insect larvae, and other sources. Algal remains constitute the biggest proportion of wild guppy diet in most cases, but diets vary depending on the specific conditions of food availability in the habitat.^[5][44] For example, a study on wild Trinidad guppies showed that guppies collected from an oligotrophic upstream region (upper Aripo River) mainly consumed invertebrates, while guppies from a eutrophic downstream region (lower Tacarigua River) consumed mostly diatoms and mineral particles. Algae are less nutritious than invertebrates, and the guppies that feed mainly on algae have poor diets.^[4]

Guppies' diet preference is not simply correlated to the abundance of a particular food. Laboratory experiments confirmed that guppies show 'diet switching' behavior, in which they feed disproportionately on the more abundant food when they are offered two food choices. The result shows that different groups of guppies have weak and variable food preference.^[45] Diet preference in guppies could be related to factors such as the presence of competitors. For example, the lower Tacarigua River has a larger variety of species and competition for invertebrate prey is higher, therefore the proportion of invertebrates is small in diets of those guppies.^[4]

ForagingEdit

Guppies often forage in groups because they can find food more easily. Shoaling guppies spend less time and energy on antipredatory behavior than solitary ones and spend more time on feeding. However, such behavior results in food that is found being shared with other members of the group. Studies also show when an evolutionary cost exists, guppies that tend to shoal are less aggressive and less competitive with regards to scarce resources.^[46] Therefore, shoaling is preferred in high-predation regions, but not in low-predation regions. When guppies with a high tendency to shoal were isolated from high-predation regions and were relocated to predator-free environments, over time, they decreased their shoaling behavior, supporting the hypothesis that shoaling is less preferred in low-predation environments.^[47]

Reproduction

Play media

Birth of guppy fry

A guppy fry in an aquarium at one week of age

Guppies are highly prolific livebearers.^[48] The gestation period of a guppy is typically 21–30 days, varying considerably. Reproduction typically continues through the year, and the female becomes ready for conception again quickly after parturition.^[4] Male guppies, like other members of the family Poeciliidae, possess a modified tubular anal fin called the gonopodium, located directly behind the ventral fin. The gonopodium has a channel-like structure through which bundles of spermatozoa, called spermatozeugmata, are transferred to females. In courted mating, where the female shows receptive behavior following the male's courtship display, the male briefly inserts the gonopodium into the female's genital pore for internal fertilization. However, in the case of sneaky mating where copulation is forced, the male approaches the female and thrusts the gonopodium at the female's urogenital pore.^[49]

Once inseminated, female guppies can store sperm in their ovaries and gonoducts, which can continue to fertilize ova up to eight months.^[50] Because of the sperm-storage mechanism, males are capable of posthumous reproduction, meaning the female mate can give birth to the male's offspring long after the male's death, which contributes significantly to the reproductive dynamics of the wild guppy populations.^[51]

The guppy has been successfully hybridised with various species of molly (Poecilia latipinna or P. velifera), e.g., male guppy and female molly. However, the hybrids are always male and appear to be infertile.^[52] The guppy has also been hybridised with the Endler's livebearer (Poecilia wingei) to produce fertile offspring, with the suggestion that, despite physical and behavioural differences, Endler's may represent a subspecies of Poecilia reticulata rather than a distinct species.^[53][54]

Inbreeding depressionEdit

Due to the extensive selective breeding of guppies for desirable traits such as greater size and colour, some strains of the fish have become less hardy than their wild counterparts. Immense inbreeding of guppies has been found to affect body size, fertility and susceptibility to diseases.^[55]

In the aquarium

Guppy standards

Large strains:
A - Veil tail
B - Triangle tail
C - Fan tail
D - Flag tail

Sword strains:
E - Double sword
F - Upper sword
G - Lower sword
H - Lyre tail

Short strains:
I - Spade tail
J - Spear tail
K - Round tail
L - Pin tail

Guppies prefer a hard-water aquarium with a temperature between 25.5 and 27.8 °C (78 and 82 °F) and salt levels equivalent to one tablespoon per 19 L (5 US gal).^[56] They can withstand levels of salinity up to 150% that of normal seawater,^[57] which has led to them being occasionally included in marine tropical community tanks, as well as in freshwater tropical tanks. Guppies are generally peaceful, though nipping behaviour is sometimes exhibited between male guppies or towards other top swimmers like members of the genus Xiphophorus (platies and swordtails), and occasionally other fish with prominent fins, such as angelfish. Guppies should not be kept as a single fish in an aquarium because both males and females show signs of shoaling, and are usually found in large groups in the wild.^[58] Its most famous characteristic is its propensity for breeding, and it can breed in both freshwater and marine aquaria.^[59]

Guppies prefer water temperatures around 22.2–26.1 °C (72–79 °F) for reproduction. Pregnant female guppies have enlarged and darkened gravid spots near their anal vents. Just before birth, the eyes of fry may be seen through the translucent skin in this area of the female's body.^[60] When birth occurs, individual offspring are dropped in sequence, typically over a period of one to six hours. The female guppy has drops of two to 200 fry at a time, typically ranging between 30 and 60.^[61]

Well-fed adults do not often eat their own young, although sometimes safe zones are required for the fry. Specially designed livebearer birthing tanks, which can be suspended inside the aquarium, are available from aquatic retailers. These also serve to shield the pregnant female from further attention from the males, which is important because the males sometimes attack the females while they are giving birth.^[62] It also provides a separate area for the newborn young as protection from being eaten by their mother.^[63] However, if a female is put in the breeder box too early, it may cause her to have a miscarriage. Well-planted tanks that offer barriers to adult guppies shelter the young quite well. Guppy grass, water sprite, water wisteria, duckweed, and java moss are all good choices. A continuous supply of live food, such as Daphnia or brine shrimp, keep adult fish full and may spare the fry when they are born.^[64] Young fry take roughly three or four months to reach maturity. Feeding fry live foods, such as baby brine shrimp, microworms, infusoria and vinegar eels, is recommended. Alternatives include finely ground flake food, egg yolk, and liquid fish food, though the particulates in these may be too large for the youngest fry to eat.^[65]

Source

Wikipedia