 | Look up paedophagy in Wiktionary, the free dictionary. |
Paedophagy (literally meaning the "consumption of children") in its general form is the feeding behaviour of fish or other animals whose diet is partially, or primarily the eggs or larvae of other animals. However, P. H. Greenwood, who was the first to describe paedophagia, defines it to be a feeding behaviour evolved among cichlid fishes. [1] [2] [3]
Paedophagy is found in fishes from Lake Victoria in Africa which in total has 200-300 species, [4] but in regards to paedophages it is known to contain 8 species. [1] Lake Malawi in Africa has in total 500-1000 species, [4] but in paedophages contains only several species. Other lakes which contain paegophages include Lake Edward and Lake George, both in Africa, and each contain only one species of paedophage. [1] From Lake Malawi there are various species of cichlid fish that exhibit paedophagia, they include fishes from the genera Caprichromis , Hemitaeniochromis , and Naevochromis. In Lake Tanganyika species of the genus Haplotaxodon and Greenwoodochromis bellcrossi may also carry out this sort of feeding strategy. [5]
Mouth brooding is the most common form of parental care in African cichlids, [2] and has thought to have evolved from the ancestral mode of care known as substrate-guarding. [6] As mouth brooding is so well known in cichlids, one of the main approaches of paedophages is to steal the brood directly from the mouth of a mother. Upon hatching, development occurs in the mouth until juveniles are well-formed fry, the fry then develop further in the mouth until ready in which they are the released. Typically followed by a phase of parental guarding. [2] Since the young are kept inside the mothers mouth for an extensive amount of their juvenile life it creates a great opportunity for paedophages, as there is a high probability of a female cichlid to possess young in her mouth.
There are three main methods or behaviours that the predators use to obtain the eggs or young. The first method is voluntary jettisoning of a brood, second being snout-engulfing which forces a brooding female to dislodge her brood from her mouth and lastly, is head-ramming against a brooding female which then causes her to spit out a part of her brood. [1] Other behaviours include those of the species Plecodus straeleni , which belongs to the family Cichlidae. [1] When this species exhibits paedophagy, it has been observed circling and waiting outside the bower, which is the spawning location for many cichlid fishes. It waits until the eggs have been laid before attacking the mouth brooder. [1] However, stealing from the mouth brooding phase is not the only tactic that has been noted, stealing of the fry from the guarding phase of parental care has also been observed. [2]
This involves juveniles who are being guarded by their parent are approached by a paedophage hunter. The parent will do its best to chase away the predator to protect the offspring, on the other hand, this abrupt movement from the parent distresses the offspring. The offspring then all aggregate together until their mother successfully comes back, where she continues with guarding behaviour. [2] There are some cases where the fry may try to enter the mother's mouth once she reappeared, but these fry would only be rejected as the threat was over. The only exception to the fry re-entering their mother's mouth is if the mother has been disturbed by the attack and feels it is unsafe, at which point she could carry out a calling movement and all the fry would enter her mouth for a short period of time before being released. [2]
To obtain the brood without causing serious harm to the mouth brooder, paedophages have features such as protrusible and distensible spacious mouths and deeply embedded teeth that are covered by a thickened oral mucosa. [2] These large mouths allow the paedophages to engulf the snout of a mouth brooder and discharge the brood, while the teeth adaptation allowed for the paedophage to avoid becoming too heavily attached to the parent which prevents the loss of the brood that the paedophage just obtained. [2]
Achieving the brood from a brooding parent can take great energy and resources from the paedophage. However, the eggs they obtain are highly nutritious and fairly large when compared to the size of other fish eggs in that they are on average 3.4mm in diameter. [7]
Cichlids are fish from the family Cichlidae in the order Cichliformes. Cichlids were traditionally classed in a suborder, the Labroidei, along with the wrasses (Labridae), in the order Perciformes, but molecular studies have contradicted this grouping. The closest living relative of cichlids is probably the convict blenny, and both families are classified in the 5th edition of Fishes of the World as the two families in the Cichliformes, part of the subseries Ovalentaria. This family is both large and diverse. 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.
Mouthbrooding, also known as oral incubation and buccal incubation, is the care given by some groups of animals to their offspring by holding them in the mouth of the parent for extended periods of time. Although mouthbrooding is performed by a variety of different animals, such as the Darwin's frog, fish are by far the most diverse mouthbrooders. Mouthbrooding has evolved independently in several different families of fish.
Alloparenting is a term used to classify any form of parental care provided by an individual towards a non-descendant young. Non-descendant refers to any young who is not the direct genetic offspring of the individual, but does not exclude related young such as siblings or grandchildren. Individuals providing this care are referred to using the neutral term of alloparent.
The convict cichlid is a fish species from the family Cichlidae, native to Central America, also known as the zebra cichlid. Convict cichlids are popular aquarium fish and have also been the subject of numerous studies on fish behaviour.
Neolamprologus brichardi is a species of cichlid endemic to the alkaline waters of Lake Tanganyika in East Africa. It is a popular aquarium fish kept in the fishkeeping hobby, where it is known under a variety of common names including Princess cichlid, Princess of Burundi, Lyretail cichlid, Fairy cichlid and Brichard's lamprologus. In addition, the species is also the subject of numerous studies on fish behaviour. It is closely related to N. pulcher from the southern half of Lake Tanganyika and some have recommended merging the two into a single species.
Julidochromis is a genus of cichlids in the subfamily Pseudocrenilabrinae. They are commonly called julies and are endemic to Lake Tanganyika in eastern Africa. This genus includes six formally described species, some with a number local variants of uncertain taxonomic status. Further taxonomic work is required to determine how many species exist; the closely related Chalinochromis with two more species is sometimes included here and this may be correct. Hybridization makes attempts to determine relationships with molecular phylogenetic methods difficult.
Tropheus moorii is a species of cichlid endemic to Lake Tanganyika in Africa. Over 40 different color morphs of this species are dispersed throughout the lake, ranging from dark green to flame red and yellow. They mostly feed on filamentous algae on the rocky shallows they inhabit. T. moorii is a maternal mouthbrooder, so eggs are fertilized and young are carried in the mouth of the female while they hatch and develop.
The Nile tilapia 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.
Variabilichromis moorii has no common name and is a species of freshwater cichlid endemic to Lake Tanganyika in eastern Africa. It is a small ovate bodied fish named for an early collector of fish from the lake, John Edmund Sharrock Moore (1870-1947) who was a cytologist, zoologist and led an expedition to Lake Tanganyika and who discovered this species. Juveniles are usually yellow, and adults are dark brown to black in color. It reaches a total length (TL) of 10.3 centimetres (4.1 in). Currently it is the only member of its genus. V. moorii feeds on algae, zooplankton, and benthic invertebrates. It is also found in the aquarium trade.
Cyphotilapia is a small genus of African cichlids endemic to Lake Tanganyika, with C. frontosa being roughly confined to the northern half of the lake and C. gibberosa roughly to the southern half. They have a distinctly banded pattern, bulbous foreheads when mature and can reach up to 33 cm in length.
The kampango or kampoyo is a critically endangered species of large and predatory bagrid catfish that is endemic to Lake Malawi, Lake Malombe and the upper Shire River in Africa. It prefers areas near rocks in water shallower than 50 m (160 ft), but it also occurs deeper and over a sandy or muddy bottom.
Herotilapia multispinosa also known as the rainbow cichlid is a Central American freshwater fish of the cichlid family. It is found on the Atlantic slope of Honduras, Nicaragua, and Costa Rica from Patuca River (Honduras) south to Matina River, and on the Pacific slope of Nicaragua and Costa Rica from Guasaule River south to Tempisque River. Specimens are also reported from the Choluteca River on the Pacific side of Honduras. This species is found in lakes and swamps with muddy bottoms, where it uses its specialized teeth and only 3.5% jaw protrusion to feed mostly on algae. It is commercially important as an aquarium fish. The rainbow cichlid prefers a pH range of 7.0–8.0, water hardness of 9-20 dGH and a temperature range of 21–36 °C.
Synodontis multipunctatus, also known as the cuckoo catfish, cuckoo squeaker, or multipunk, is a small catfish from Lake Tanganyika, one of the lakes in the Great Rift Valley system in Africa. It is a brood parasite upon mouthbrooding cichlids. This species grows to a length of 27.5 centimetres (10.8 in) TL. This species is a minor component of local commercial fisheries.
Lepidophagy is a specialised feeding behaviour in fish that involves eating of scales of other fish. Lepidophagy is widespread, having been independently evolved in at least five freshwater families and seven marine families. A related feeding behavior is pterygophagy, which are fish that feed on the fins of other fish.
Cyprichromis leptosoma is a mouthbrooding species of fish in the family Cichlidae. It is endemic to Lake Tanganyika in Zambia and Tanzania. It seems quite common within its range and faces no particular threats, so the International Union for Conservation of Nature has assessed its conservation status as being of least concern.
Malawi eyebiter is a species of fish in the family Cichlidae. This predatory cichlid is endemic to Lake Malawi in East Africa.
Plecodus straeleni is a species of cichlid fish that is endemic to Lake Tanganyika in East Africa. This species can reach a total length of 16 centimetres (6.3 in).
Spawn is the eggs and sperm released or deposited into water by aquatic animals. As a verb, to spawn refers to the process of releasing the eggs and sperm, and the act of both sexes is called spawning. Most aquatic animals, except for aquatic mammals and reptiles, reproduce through the process of spawning.
The mango tilapia is a species of fish from the cichlid family that is native to fresh and brackish waters in Africa and the Levant. Other common names include Galilaea tilapia, Galilean comb, Galilee St. Peter's fish, and St. Peter's fish.. This is a relatively large cichlid at up to 41 centimetres (16 in) in total length and about 1.6 kilograms (3.5 lb) in weight. It is very important to local fisheries and the species is also aquacultured.
Vertebrate maternal behavior is a form of parental care that is specifically given to young animals by their mother in order to ensure the survival of the young. Parental care is a form of altruism, which means that the behaviors involved often require a sacrifice that could put their own survival at risk. This encompasses behaviors that aid in the evolutionary success of the offspring and parental investment, which is a measure of expenditure exerted by the parent in an attempt to provide evolutionary benefits to the offspring. Therefore, it is a measure of the benefits versus costs of engaging in the parental behaviors. Behaviors commonly exhibited by the maternal parent include feeding, either by lactating or gathering food, grooming young, and keeping the young warm. Another important aspect of parental care is whether the care is provided to the offspring by each parent in a relatively equal manner, or whether it is provided predominantly or entirely by one parent. There are several species that exhibit biparental care, where behaviors and/or investment in the offspring is divided equally amongst the parents. This parenting strategy is common in birds. However, even in species who exhibit biparental care, the maternal role is essential since the females are responsible for the incubation and/or delivery of the young.
| About fish |  | ||||
|---|---|---|---|---|---|
| Anatomy and physiology | |||||
| Sensory systems | |||||
| Reproduction | |||||
| Locomotion | |||||
| Other behaviour | |||||
| By habitat | |||||
| Other types | |||||
| Commerce |
| ||||
| Major groups | |||||
| Lists | |||||
| Carnivores |
|  | ||||||
|---|---|---|---|---|---|---|---|---|
| Herbivores | ||||||||
| Cellular | ||||||||
| Others | ||||||||
| Methods | ||||||||
