Cichlids 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 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 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.
The oscar is a species of fish from the cichlid family known under a variety of common names, including tiger oscar, velvet cichlid, and marble cichlid. In tropical South America, where the species naturally resides, A. ocellatus specimens are often found for sale as a food fish in the local markets. The fish has been introduced to other areas, including India, China, Australia, and the United States. It is considered a popular aquarium fish in Europe and the U.S.
In ethology, territory is the sociographical area that an animal consistently defends against conspecific competition using agonistic behaviors or real physical aggression. Animals that actively defend territories in this way are referred to as being territorial or displaying territorialism.
The Siamese fighting fish, commonly known as the betta, is a freshwater fish native to Southeast Asia, namely Cambodia, Laos, Myanmar, Malaysia, Indonesia, Thailand, and Vietnam. It is one of 76 species of the genus Betta, but the only one eponymously called "betta", owing to its global popularity as a pet; Betta splendens are among the most popular aquarium fish in the world, due to their diverse and colorful morphology and relatively low maintenance.
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.
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.
Cats communicate for a variety of reasons, including to show happiness, express anger, solicit attention, and observe potential prey. Additionally, they collaborate, play, and share resources. When cats communicate with humans, they do so to get what they need or want, such as food, water, attention, or play. As such, cat communication methods have been significantly altered by domestication. Studies have shown that domestic cats tend to meow much more than feral cats. They rarely meow to communicate with fellow cats or other animals. Cats can socialize with each other and are known to form "social ladders," where a dominant cat is leading a few lesser cats. This is common in multi-cat households.
Lamprologus ocellatus is a species of shell dwelling cichlid endemic to Lake Tanganyika. It is a popular aquarium fish due to its small size, appearance, and intelligence.
Agonism is a broad term which encompasses many behaviours that result from, or are triggered by biological conflict between competing organisms. It is defined as "survivalist animal behaviour that includes aggression, defense, and avoidance". Approximately 23 shark species are capable of producing such displays when threatened by intraspecific or interspecific competitors, as an evolutionary strategy to avoid unnecessary combat. The behavioural, postural, social and kinetic elements which comprise this complex, ritualized display can be easily distinguished from normal, or non-display behaviour, considered typical of that species' life history. The display itself confers pertinent information to the foe regarding the displayer's physical fitness, body size, inborn biological weaponry, confidence and determination to fight. This behaviour is advantageous because it is much less biologically taxing for an individual to display its intention to fight than the injuries it would sustain during conflict. Agonistic displays are essential to the social dynamics of many biological taxa, extending far beyond sharks.
The Mozambique tilapia is an oreochromine cichlid fish native to southeastern Africa. Dull colored, the Mozambique tilapia often lives up to a decade in its native habitats. It is a popular fish for aquaculture. Due to human introductions, it is now found in many tropical and subtropical habitats around the globe, where it can become an invasive species because of its robust nature. These same features make it a good species for aquaculture because it readily adapts to new situations. It is known as black tilapia in Colombia and as blue kurper in South Africa.
The Tennessee dace is a species of ray-finned fish in the family Cyprinidae. It is found only in the United States; particularly in northeast Tennessee and southwest Virginia, and parts of extreme northwest Georgia. Until recently, they were considered a subspecies of mountain redbelly dace. They are commonly found in East Tennessee in spring fed first-order streams, often in silt and fine gravel pools, or undercut banks. These streams usually do not exceed two meters in width.
Agonistic behaviour is any social behaviour related to fighting. The term has broader meaning than aggressive behaviour because it includes threats, displays, retreats, placation, and conciliation. The term "agonistic behaviour" was first defined and used by J.P Scott and Emil Fredericson in 1951 in their paper "The Causes of Fighting in Mice and Rats" in Physiological Zoology.Agonistic behaviour is seen in many animal species because resources including food, shelter, and mates are often limited.
The Malawi eyebiter is a species of fish in the family Cichlidae. This predatory cichlid is found in Lake Malawi, Lake Malombe, and the upper Shire River within East Africa.
Semotilus atromaculatus, known as the creek chub or the common creek chub, is a small minnow, a freshwater fish found in the eastern US and Canada. Differing in size and color depending on origin of development, the creek chub can usually be defined by a dark brown body with a black lateral line spanning horizontally across the body. It lives primarily within streams and rivers. Creek chubs attain lengths of 2–6 inches (5.1–15.2 cm) with larger specimens of up to 12 inches (30 cm) long.
The goldeneye cichlid is a species of cichlid found in fresh water from the Aruka River in Guyana, to the Maroni River in Suriname. It is often found on flooded savannas near the coast. The male grows to a length of about 5.6 centimetres (2.2 in) while the female is somewhat smaller, and is thus regarded as a dwarf cichlid.
The black-faced blenny is a small benthic fish from the family Tripterygiidae (triplefin-blennies). It occurs at depths of 3 to 40 metres and lives on the substrate under large rocks, cliffs or other overhangs.
Self-anointing in animals, sometimes called anointing or anting, is a behaviour whereby a non-human animal smears odoriferous substances over themselves. These substances are often the secretions, parts, or entire bodies of other animals or plants. The animal may chew these substances and then spread the resulting saliva mixture over their body, or they may apply the source of the odour directly with an appendage, tool or by rubbing their body on the source.
Aggression refers to agonistic behaviors characterized by threats and physical force. Methods of aggression in fish vary widely by species, but some common examples are chasing, charging, biting, fin display, color changes, and flared gills. Aggression is an important evolutionary pressure that increases an individual's access to resources while reducing overall conflict within the social group. Fish use aggressive behaviors to defend a territory, establish dominance, appeal to potential mates, and protect their young.
The Dixie chub is a species of freshwater ray-finned fish from the carp and minnow family Cyprinidae. It is endemic to southeastern United States.
