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54-504: During Richard Leakey's original 1967 excavations several stone tools were found in association with Omo 1 at Kamoya's hominid site (KHS) but were not well described in the research literature. In the 2000s further excavations occurred at KHS in addition to two other sites: Awoke's hominid site (AHS) also located in Member 1 and the Bird's Nest Site (BNS) located in Member 2. Summaries of

108-1054: A dagger (†); groups of uncertain placement are labelled with a question mark (?) and dashed lines (- - - - -). Jawless fishes (118 species: hagfish , lampreys ) [REDACTED] † Thelodonti , † Conodonta , † Anaspida [REDACTED] [REDACTED] [REDACTED] † Galeaspida [REDACTED] † Osteostraci [REDACTED] † Placodermi [REDACTED] † Acanthodii [REDACTED]  (>1,100 species: sharks , rays , chimaeras ) [REDACTED]  (2 species: coelacanths ) [REDACTED] Dipnoi (6 species: lungfish ) [REDACTED] Tetrapoda (>38,000 species, not considered fish: amphibians, reptiles, birds, mammals) [REDACTED]  (14 species: bichirs , reedfish ) [REDACTED]  (27 species: sturgeons , paddlefish ) [REDACTED] Ginglymodi (7 species: gars , alligator gars ) [REDACTED] Halecomorphi (2 species: bowfin , eyetail bowfin ) [REDACTED]  (>32,000 species) [REDACTED] Fishes (without tetrapods) are

162-579: A paraphyletic group and for this reason, the class Pisces seen in older reference works is no longer used in formal classifications. Traditional classification divides fish into three extant classes (Agnatha, Chondrichthyes, and Osteichthyes), and with extinct forms sometimes classified within those groups, sometimes as their own classes. Fish account for more than half of vertebrate species. As of 2016, there are over 32,000 described species of bony fish, over 1,100 species of cartilaginous fish, and over 100 hagfish and lampreys. A third of these fall within

216-417: A Christian missionary school for six years, but left once he was old enough to herd the family goats in the field. The native language of his family was Kikamba . He also learned to speak English and Swahili , which proved invaluable in later life, when he translated for visiting scientists with whom he worked. Kimeu began to work in paleoanthropology as a laborer for Louis Leakey and Mary Leakey in

270-436: A more spherical lens . Their retinas generally have both rods and cones (for scotopic and photopic vision ); many species have colour vision , often with three types of cone. Teleosts can see polarized light ; some such as cyprinids have a fourth type of cone that detects ultraviolet . Amongst jawless fish , the lamprey has well-developed eyes, while the hagfish has only primitive eyespots. Hearing too

324-419: A protective bony cover or operculum . They are able to oxygenate their gills using muscles in the head. Some 400 species of fish in 50 families can breathe air, enabling them to live in oxygen-poor water or to emerge on to land. The ability of fish to do this is potentially limited by their single-loop circulation, as oxygenated blood from their air-breathing organ will mix with deoxygenated blood returning to

378-441: A sense of touch and of hearing . Blind cave fish navigate almost entirely through the sensations from their lateral line system. Some fish, such as catfish and sharks, have the ampullae of Lorenzini , electroreceptors that detect weak electric currents on the order of millivolt. Vision is an important sensory system in fish. Fish eyes are similar to those of terrestrial vertebrates like birds and mammals, but have

432-485: A tail fin, jaws, skin covered with scales , and lays eggs. Each criterion has exceptions, creating a wide diversity in body shape and way of life. For example, some fast-swimming fish are warm-blooded, while some slow-swimming fish have abandoned streamlining in favour of other body shapes. Fish species are roughly divided equally between freshwater and marine (oceanic) ecosystems; there are some 15,200 freshwater species and around 14,800 marine species. Coral reefs in

486-585: A true "land fish" as this worm-like catfish strictly lives among waterlogged leaf litter . Cavefish of multiple families live in underground lakes , underground rivers or aquifers . Like other animals, fish suffer from parasitism . Some species use cleaner fish to remove external parasites. The best known of these are the bluestreak cleaner wrasses of coral reefs in the Indian and Pacific oceans. These small fish maintain cleaning stations where other fish congregate and perform specific movements to attract

540-422: A typical fish is adapted for efficient swimming by alternately contracting paired sets of muscles on either side of the backbone. These contractions form S-shaped curves that move down the body. As each curve reaches the tail fin, force is applied to the water, moving the fish forward. The other fins act as control surfaces like an aircraft's flaps, enabling the fish to steer in any direction. Since body tissue

594-423: Is an aquatic , anamniotic , gill -bearing vertebrate animal with swimming fins and a hard skull , but lacking limbs with digits . Fish can be grouped into the more basal jawless fish and the more common jawed fish , the latter including all living cartilaginous and bony fish , as well as the extinct placoderms and acanthodians . Most fish are cold-blooded , their body temperature varying with

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648-465: Is an important sensory system in fish. Fish sense sound using their lateral lines and otoliths in their ears, inside their heads. Some can detect sound through the swim bladder. Some fish, including salmon, are capable of magnetoreception ; when the axis of a magnetic field is changed around a circular tank of young fish, they reorient themselves in line with the field. The mechanism of fish magnetoreception remains unknown; experiments in birds imply

702-431: Is denser than water, fish must compensate for the difference or they will sink. Many bony fish have an internal organ called a swim bladder that allows them to adjust their buoyancy by increasing or decreasing the amount of gas it contains. The scales of fish provide protection from predators at the cost of adding stiffness and weight. Fish scales are often highly reflective; this silvering provides camouflage in

756-706: Is known as the Peninj Mandible . Kimeu was described as “a legend...responsible for some of the most significant fossil finds that shaped our understanding of our evolutionary past” by Carol Ward, a professor of anatomy at the University of Missouri. Kimeu died from kidney failure on 20 July 2022 in Nairobi , Kenya. He believed his age to be approximately 84. Kimeu has two fossil primates named after him: Kamoyapithecus hamiltoni and Cercopithecoides kimeui . Fish A fish ( pl. : fish or fishes )

810-585: Is predicted that early hominins obtained the necessary rock clasts to produce stone tools from local sources. Although all materials could be found in sufficient quantities in local gravel deposits, low quality materials such as shale, rhyolite and basalt were significantly more abundant. Moreover, high quality cores were more significantly reduced than were low quality cores. Together, these trends suggest that hominins were highly selective in their stone tool production. Sixty-nine percent of all cores are levallois cores or asymmetrical discoids which belong to

864-465: Is the biggest part of the brain; it is small in hagfish and lampreys , but very large in mormyrids , processing their electrical sense . The brain stem or myelencephalon controls some muscles and body organs, and governs respiration and osmoregulation . The lateral line system is a network of sensors in the skin which detects gentle currents and vibrations, and senses the motion of nearby fish, whether predators or prey. This can be considered both

918-606: The Gnathostomata or (for bony fish) Osteichthyes , also contains the clade of tetrapods (four-limbed vertebrates, mostly terrestrial), which are usually not considered fish. Some tetrapods, such as cetaceans and ichthyosaurs , have secondarily acquired a fish-like body shape through convergent evolution . Fishes of the World comments that "it is increasingly widely accepted that tetrapods, including ourselves, are simply modified bony fishes, and so we are comfortable with using

972-709: The Indo-Pacific constitute the center of diversity for marine fishes, whereas continental freshwater fishes are most diverse in large river basins of tropical rainforests , especially the Amazon , Congo , and Mekong basins. More than 5,600 fish species inhabit Neotropical freshwaters alone, such that Neotropical fishes represent about 10% of all vertebrate species on the Earth. Fish are abundant in most bodies of water. They can be found in nearly all aquatic environments, from high mountain streams (e.g., char and gudgeon ) to

1026-540: The National Geographic Society 's LaGorce Medal and with an honorary doctorate of science degree from Case Western Reserve University . Kamoya Kimeu was born in 1938 in Makueni County , a rural area of southern Kenya , to Philomena Mwelu and Kimeu Mbalu. His father was a goat herder, but at the time of Kamoya's birth, was away working on a railroad construction project. Young Kamoya Kimeu attended

1080-661: The Silurian , with giant armoured placoderms such as Dunkleosteus . Jawed fish, too, appeared during the Silurian: the cartilaginous Chondrichthyes and the bony Osteichthyes . During the Devonian , fish diversity greatly increased, including among the placoderms, lobe-finned fishes, and early sharks, earning the Devonian the epithet "the age of fishes". Fishes are a paraphyletic group, since any clade containing all fish, such as

1134-469: The abyssal and even hadal depths of the deepest oceans (e.g., cusk-eels and snailfish ), although none have been found in the deepest 25% of the ocean. The deepest living fish in the ocean so far found is a cusk-eel, Abyssobrotula galatheae , recorded at the bottom of the Puerto Rico Trench at 8,370 m (27,460 ft). In terms of temperature, Jonah's icefish live in cold waters of

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1188-440: The end-Devonian extinction wiped out the apex predators , the placoderms. Bony fish are further divided into the lobe-finned and ray-finned fish . About 96% of all living fish species today are teleosts , a crown group of ray-finned fish that can protrude their jaws . The tetrapods , a mostly terrestrial clade of vertebrates that have dominated the top trophic levels in both aquatic and terrestrial ecosystems since

1242-400: The intertidal zone , are facultative air breathers, able to breathe air when out of water, as may occur daily at low tide , and to use their gills when in water. Some coastal fish like rockskippers and mudskippers choose to leave the water to feed in habitats temporarily exposed to the air. Some catfish absorb air through their digestive tracts. The digestive system consists of a tube,

1296-405: The ostracoderms , had heavy bony plates that served as protective exoskeletons against invertebrate predators . The first fish with jaws , the placoderms, appeared in the Silurian and greatly diversified during the Devonian , the "Age of Fishes". Bony fish, distinguished by the presence of swim bladders and later ossified endoskeletons , emerged as the dominant group of fish after

1350-425: The stout infantfish . Swimming performance varies from fish such as tuna, salmon , and jacks that can cover 10–20 body-lengths per second to species such as eels and rays that swim no more than 0.5 body-lengths per second. A typical fish is cold-blooded , has a streamlined body for rapid swimming, extracts oxygen from water using gills, has two sets of paired fins, one or two dorsal fins, an anal fin and

1404-607: The 1950s. During his job interview, Louis Leakey spoke with him in fluent Kikuyu , a similar language to Kikamba, which encouraged Kimeu to work with the team. In 1963, he joined the expeditions led by Richard Leakey , the son of Mary and Louis who followed in their footsteps as a paleoanthropologist. Kimeu accompanied him to the Omo River and Lake Rudolf (now Lake Turkana ) in 1967. He quickly became Richard Leakey's right-hand man, assuming control of field operations in Leakey's absence. He

1458-510: The 337 specimens likely belonged to the same individuals, it is believed that summaries of the taxonomic frequencies is not greatly impacted by this fact. Together perciforms and siluriforms (catfish) comprise a staggering 86.7 percent of the Kibish assemblage. Importantly, the order perciform is represented entirely by a single species ( Lates niloticus ) while 76 percent of siluriforms are represented by Synodontis and clariids. Although

1512-417: The Kibish ichthyofauna does not closely approximate the documented biodiversity of the extant community (9 out of the 37 known genera were identified), overall it is similar to the modern fauna in the region. Member III contained all nine genera while Member I was missing Hydrocynus and Schilbe ; nonetheless the two members were similar in the taxonomic frequencies (by order). Member IV contained only

1566-446: The Kibish taxa, such as their large size or preference for open waters habitats suggest that they would indeed require tools to be procured. 4°48′1.27″N 35°58′1.45″E  /  4.8003528°N 35.9670694°E  / 4.8003528; 35.9670694 Kamoya Kimeu Kamoya Kimeu (1938 – 20 July 2022) was a Kenyan paleontologist and curator, whose contributions to the field of paleoanthropology were recognised with

1620-610: The Late Paleozoic , evolved from lobe-finned fish during the Carboniferous , developing air-breathing lungs homologous to swim bladders. Despite the cladistic lineage, tetrapods are usually not considered to be fish, making "fish" a paraphyletic group. Fish have been an important natural resource for humans since prehistoric times, especially as food . Commercial and subsistence fishers harvest fish in wild fisheries or farm them in ponds or in breeding cages in

1674-594: The Southern Ocean, including under the Filchner–Ronne Ice Shelf at a latitude of 79°S, while desert pupfish live in desert springs, streams, and marshes, sometimes highly saline, with water temperatures as high as 36 C. A few fish live mostly on land or lay their eggs on land near water. Mudskippers feed and interact with one another on mudflats and go underwater to hide in their burrows. A single undescribed species of Phreatobius has been called

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1728-556: The attention of the cleaners. Cleaning behaviors have been observed in a number of fish groups, including an interesting case between two cichlids of the same genus, Etroplus maculatus , the cleaner, and the much larger E. suratensis . Fish occupy many trophic levels in freshwater and marine food webs . Fish at the higher levels are predatory , and a substantial part of their prey consists of other fish. In addition, mammals such as dolphins and seals feed on fish, alongside birds such as gannets and cormorants . The body of

1782-550: The body, and produce a concentrated urine. The reverse happens in freshwater fish : they tend to gain water osmotically, and produce a dilute urine. Some fish have kidneys able to operate in both freshwater and saltwater. Fish have small brains relative to body size compared with other vertebrates, typically one-fifteenth the brain mass of a similarly sized bird or mammal. However, some fish have relatively large brains, notably mormyrids and sharks , which have brains about as large for their body weight as birds and marsupials . At

1836-414: The categorical class known as formal cores. Though the Kibish industry possess some characteristics that support the possibility of stone tool production aimed to accommodate high residential mobility, there are as well contradictory characteristics. For example, retouched tools are on the whole rare but the proportion of bifacially retouched tools is minuscule. In comparison to other MSA assemblages

1890-591: The cores were particularly small. However, it was hypothesized that this was a likely result of starting from smaller clasts. Despite such differences, paleoanthropologist John Shea concludes that the Kibish Industry seems to be a local variant of the larger east African industry yet to be named. Research by Assefa et al. sampled all members but obtained faunal remains from only Members I, III, and IV. The faunal assemblages obtained from each member are similar in their diversity of mammals and are largely representative of

1944-561: The exact root is unknown; some authorities reconstruct a Proto-Indo-European root * peysk- , attested only in Italic , Celtic , and Germanic . About 530 million years ago during the Cambrian explosion , fishlike animals with a notochord and eyes at the front of the body, such as Haikouichthys , appear in the fossil record . During the late Cambrian , other jawless forms such as conodonts appear. Jawed vertebrates appear in

1998-593: The extant community. The presence of H. meinertzhageni and Cephalophus is interesting because they are reportedly rare in the African fossil record having occurred in few sites such as the Matupi Cave . Another notable find within the fossil fauna is that of Equus burchellii and E. grevyi because this may suggests that the Omo Kibish area has for a long time been an exception to the otherwise rare coexistence of

2052-405: The front of the brain are the olfactory lobes , a pair of structures that receive and process signals from the nostrils via the two olfactory nerves . Fish that hunt primarily by smell, such as hagfish and sharks, have very large olfactory lobes. Behind these is the telencephalon , which in fish deals mostly with olfaction. Together these structures form the forebrain. Connecting the forebrain to

2106-412: The gills flows in the opposite direction to the water, resulting in efficient countercurrent exchange . The gills push the oxygen-poor water out through openings in the sides of the pharynx. Cartilaginous fish have multiple gill openings: sharks usually have five, sometimes six or seven pairs; they often have to swim to oxygenate their gills. Bony fish have a single gill opening on each side, hidden beneath

2160-532: The gills. Oxygen-rich blood then flows without further pumping, unlike in mammals, to the body tissues. Finally, oxygen-depleted blood returns to the heart. Fish exchange gases using gills on either side of the pharynx . Gills consist of comblike structures called filaments. Each filament contains a capillary network that provides a large surface area for exchanging oxygen and carbon dioxide . Fish exchange gases by pulling oxygen-rich water through their mouths and pumping it over their gills. Capillary blood in

2214-447: The gut, leading from the mouth to the anus. The mouth of most fishes contains teeth to grip prey, bite off or scrape plant material, or crush the food. An esophagus carries food to the stomach where it may be stored and partially digested. A sphincter, the pylorus, releases food to the intestine at intervals. Many fish have finger-shaped pouches, pyloric caeca , around the pylorus, of doubtful function. The pancreas secretes enzymes into

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2268-402: The heart from the rest of the body. Lungfish, bichirs, ropefish, bowfins, snakefish, and the African knifefish have evolved to reduce such mixing, and to reduce oxygen loss from the gills to oxygen-poor water. Bichirs and lungfish have tetrapod-like paired lungs, requiring them to surface to gulp air, and making them obligate air breathers. Many other fish, including inhabitants of rock pools and

2322-455: The intestine to digest the food; other enzymes are secreted directly by the intestine itself. The liver produces bile which helps to break up fat into an emulsion which can be absorbed in the intestine. Most fish release their nitrogenous wastes as ammonia . This may be excreted through the gills or filtered by the kidneys . Salt is excreted by the rectal gland. Saltwater fish tend to lose water by osmosis ; their kidneys return water to

2376-488: The large mammals which comprise the current community of fauna in the area. That is, predominantly bovids , suids , and equids but also other ungulates such as hippopotamuses, rhinoceroses etc. The fossil fauna sample falls short in terms of its limited representation of primates (only a single specimen) and carnivores ; some bovid species are not represented at all. Conversely, Hylochoerus meinertzhageni and Cephalophus are sampled in fossil fauna but are not in

2430-486: The lithic assemblages found during the more recent excavations also consider the lithics found in the initial 1967 excavation. The most common material used to produce the lithics found is chert. In general high quality fine-grained cryptocrystalline silicate raw materials such as jasper, chert, chalcedony comprise the clear majority (60-90% ) across all sites. Given that all but one rare occurring material could be found in contemporary gravel deposits in Member 1, it

2484-419: The midbrain is the diencephalon ; it works with hormones and homeostasis . The pineal body is just above the diencephalon; it detects light, maintains circadian rhythms, and controls color changes. The midbrain contains the two optic lobes . These are very large in species that hunt by sight, such as rainbow trout and cichlids . The hindbrain controls swimming and balance.The single-lobed cerebellum

2538-443: The nine largest families; from largest to smallest, these are Cyprinidae , Gobiidae , Cichlidae , Characidae , Loricariidae , Balitoridae , Serranidae , Labridae , and Scorpaenidae . About 64 families are monotypic , containing only one species. Fish range in size from the huge 16-metre (52 ft) whale shark to some tiny teleosts only 8-millimetre (0.3 in) long, such as the cyprinid Paedocypris progenetica and

2592-496: The ocean. Fish are caught for recreation , or raised by fishkeepers as ornaments for private and public exhibition in aquaria and garden ponds . Fish have had a role in human culture through the ages, serving as deities , religious symbols, and as the subjects of art, books and movies. The word fish is inherited from Proto-Germanic , and is related to German Fisch , the Latin piscis and Old Irish īasc , though

2646-402: The open ocean. Because the water all around is the same colour, reflecting an image of the water offers near-invisibility. Fish have a closed-loop circulatory system . The heart pumps the blood in a single loop throughout the body; for comparison, the mammal heart has two loops, one for the lungs to pick up oxygen, one for the body to deliver the oxygen. In fish, the heart pumps blood through

2700-547: The surrounding water, though some large active swimmers like white shark and tuna can hold a higher core temperature . Many fish can communicate acoustically with each other, such as during courtship displays . The study of fish is known as ichthyology . The earliest fish appeared during the Cambrian as small filter feeders ; they continued to evolve through the Paleozoic , diversifying into many forms. The earliest fish with dedicated respiratory gills and paired fins ,

2754-415: The taxon Osteichthyes as a clade, which now includes all tetrapods". The biodiversity of extant fish is unevenly distributed among the various groups; teleosts , bony fishes able to protrude their jaws , make up 96% of fish species. The cladogram shows the evolutionary relationships of all groups of living fishes (with their respective diversity ) and the tetrapods. Extinct groups are marked with

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2808-657: The three predominant genera ( Lates , Synodontis and Clarias ). Although there are no suggestive markings on the fossil material itself, other lines of evidence suggest that fishing was an established method of subsistence for hominids occupying the Omo Turkana Basin. The main evidence includes barbed bone points, similar to those in other MSA sites, found in Member IV. In said MSA sites in eastern and southern Africa, these bone points were found in association with processed fish material. Moreover, characteristics of some of

2862-493: The two species in a given habitat. It is predicted that inadequate sample size rather than the existence of only current fauna during the late- middle Pleistocene may explain the absence of any extinct species within the Kibish Formation. In total, 337 skeletal specimens of fish were collected from the Kibish formation members; as in the case of the mammals, fossils were found only in members I,III and IV. Although some of

2916-525: Was known by colleagues as, Mr. Kamoya. In 1977, he became the National Museums of Kenya 's curator for all prehistoric sites in Kenya. Significant fossil discoveries by Kimeu include a Homo habilis skull known as KNM-ER 1813 , an almost complete Homo ergaster skeleton known as KNM-WT 15000 or Turkana Boy (also known as Nariokotome boy), and in 1964, the jaw of a Paranthropus boisei hominid that

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