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35-448: Podiceps ruficollis The little grebe ( Tachybaptus ruficollis ), also known as dabchick , is a member of the grebe family of water birds . The genus name is from Ancient Greek takhus "fast" and bapto "to sink under". The specific ruficollis is from Latin rufus "red" and Modern Latin -collis , "-necked", itself derived from Latin collum "neck". At 23 to 29 centimetres (9 to 11 + 1 ⁄ 2 inches) in length it

70-478: A common ancestor of flamingos and grebes. The extinct stem-flamingo family Palaelodidae have been suggested to be the transitional linkage between the filter-feeding flamingos and the foot-propelled diving grebes. The evidence for this comes from the overall similarity between the foot and limb structure of grebes and palaeloids, suggesting the latter family of waterbirds were able to swim and dive better than flamingos. Some early grebes share similar characteristics to

105-470: A high concentration of paraffin. The secretion provides a dual purpose of protecting the feathers from external parasites and fungi, as well as waterproofing them. When preening , grebes eat their own feathers and feed them to their young. The function of this behaviour is uncertain, but it is believed to assist with pellet formation, excreting out internal parasites and protecting their insides from sharp bone material during digestion. The ventral plumage

140-495: A nearly cosmopolitan clade of waterbirds , found on every continent except Antarctica . They are absent from the Arctic Circle and arid environments. They have successfully colonized islands such as Madagascar and New Zealand . Some species such as the eared grebe ( Podiceps nigricollis ) and great crested grebe ( P. cristatus ) are found on multiple continents with regional subspecies or populations. A few species like

175-433: A radically distinct group of birds as regards their anatomy . Accordingly, they were at first believed to be related to the loons , which are also foot-propelled diving birds, and both families were once classified together under the order Colymbiformes . However, as early as the 1930s, this was determined to be an example of convergent evolution caused by the strong selective forces encountered by unrelated birds sharing

210-525: A similar appearance as a result of convergent evolution or even mimicry . In addition, there can be morphological differences within a species, such as in Apoica flavissima where queens are significantly smaller than workers. A further problem with relying on morphological data is that what may appear morphologically to be two distinct species may in fact be shown by DNA analysis to be a single species. The significance of these differences can be examined through

245-479: A single family , the Podicipedidae , which includes 22 species in six extant genera . Although, superficially, they resemble other diving birds such as loons and coots , they are most closely related to flamingos , as supported by morphological , molecular and paleontological data. Many species are monogamous and are known for their courtship displays, with the pair performing synchronized dances across

280-399: A yellow bill with a small black tip, and black and white streaks on the cheeks and sides of the neck as seen below. This yellow bill darkens as the juveniles age, eventually turning black in adulthood. In winter, its size, buff plumage , with a darker back and cap, and “powder puff” rear end enable easy identification of this species. The little grebe's breeding call, given singly or in duet,

315-482: Is a trilled repeated weet-weet-weet or wee-wee-wee which sounds like a horse whinnying. This bird breeds in small colonies in heavily vegetated areas of freshwater lakes across Europe, much of Asia down to New Guinea , and most of Africa . Most birds move to more open or coastal waters in winter, but it is only migratory in those parts of its range where the waters freeze. Outside of breeding season, it moves into more open water, occasionally even appearing on

350-472: Is a branch of life science dealing with the study of the gross structure of an organism or taxon and its component parts. The etymology of the word "morphology" is from the Ancient Greek μορφή ( morphḗ ), meaning "form", and λόγος ( lógos ), meaning "word, study, research". While the concept of form in biology, opposed to function , dates back to Aristotle (see Aristotle's biology ),

385-598: Is possibly from the Breton "krib" meaning 'comb', this referring to the crests of many of the European species. However, grèbe was used to refer to gulls. The appearance of "grebe" in the English language was introduced in 1768 by the Welsh naturalist Thomas Pennant when he adopted the word for the family. Some of the smaller species are often referred to as "dabchick", which originated in

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420-485: Is said to exemplify the two major deviations in biological thinking at the time – whether animal structure was due to function or evolution. Most taxa differ morphologically from other taxa. Typically, closely related taxa differ much less than more distantly related ones, but there are exceptions to this. Cryptic species are species which look very similar, or perhaps even outwardly identical, but are reproductively isolated. Conversely, sometimes unrelated taxa acquire

455-526: Is the most dense, described as very fur-like. By pressing their feathers against the body, grebes can adjust their buoyancy . In the nonbreeding season, grebes are plain-coloured in dark browns and whites. However, most have ornate and distinctive breeding plumages, often developing chestnut markings on the head area, and perform elaborate display rituals. The young, particularly those of the genus Podiceps , are often striped and retain some of their juvenile plumage even after reaching full size. The grebes are

490-646: Is the smallest European member of its family. It is commonly found in open bodies of water across most of its range. The little grebe was described by the German naturalist Peter Simon Pallas in 1764 and given the binomial name Colymbus ruficollis . The tricolored grebe was formerly considered conspecific, with some taxonomic authorities still considering it so. Seven subspecies are currently accepted, four widespread, and three with restricted ranges; they are separated principally by size, eye colour, which varies from dark to light from west to east, and extent of white on

525-446: The Junin grebe ( P. taczanowskii ) and the recently extinct Atitlán grebe ( Podilymbus gigas ) are lake endemics. During the warmer or breeding seasons, many species of grebes in the northern hemisphere reside in a variety of freshwater habitats like lakes and marshes . Once winter arrives many will migrate to marine environments along the coastlines. Grebes are most prevalent in

560-495: The New World with almost half of the world's species native there. Morphology (biology) This includes aspects of the outward appearance (shape, structure, color, pattern, size), i.e. external morphology (or eidonomy ), as well as the form and structure of internal parts like bones and organs , i.e. internal morphology (or anatomy ). This is in contrast to physiology , which deals primarily with function. Morphology

595-530: The least grebe ( Tachybaptus dominicus ), at 120 g (4.2 oz) and 23.5 cm (9.3 in), to the great grebe ( Podiceps major ), at 1.7 kg (3.7 lb) and 71 cm (28 in). Despite these size differences grebes are a homogenous family of waterbirds with very few or slight differences among the genera. On the surface of the water they swim low with just the head and neck exposed. All species have lobed toes, and are excellent swimmers and divers. The feet are always large, with broad lobes on

630-421: The ulna is long and fairly weak, supporting secondary feathers. There are 11 primaries and 17 to 22 secondaries, with the inner secondaries being longer than the primaries. As such grebes are generally not strong or rapid fliers. Some species are reluctant to fly. Indeed, two South American species are completely flightless. Since grebes generally dive more than fly, the sternum can be as small or even smaller than

665-612: The Northern Hemisphere fossil record in the Early Miocene, they are likely to have originated in the Southern Hemisphere. A few more recent grebe fossils could not be assigned to modern or prehistoric genera: To date there is no complete phylogeny of grebes based on molecular work. However, there are comprehensive morphological works from Bochenski (1994), Fjeldså (2004) and Ksepka et al. (2013) that have been done on

700-413: The coast in small bays. The little grebe is an excellent swimmer and diver and pursues its fish and aquatic invertebrate prey underwater. It uses the vegetation skilfully as a hiding place. Like all grebes, it nests at the water's edge, since its legs are set very far back and it cannot walk well. Usually four to seven eggs are laid. When the adult bird leaves the nest it usually takes care to cover

735-482: The coracoid and humerus seen in palaeloids. True grebes suddenly appear in the fossil record in the Late Oligocene or Early Miocene , around 23–25  mya . There are a few prehistoric genera that are now completely extinct. Thiornis and Pliolymbus date from a time when most if not all extant genera were already present. Because grebes are evolutionarily isolated and they only started to appear in

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770-676: The eggs with weeds. This makes it less likely to be detected by predators. The young leave the nest and can swim soon after hatching, and chicks are often carried on the backs of the swimming adults. In India , the species breeds during the rainy season. Grebe Grebes ( / ˈ ɡ r iː b z / ) are aquatic diving birds in the order Podicipediformes ( / ˌ p ɒ d ɪ s ɪ ˈ p ɛ d ɪ f ɔːr m iː z / ). Grebes are widely distributed freshwater birds, with some species also found in marine habitats during migration and winter. Most grebes fly, although some flightless species exist, most notably in stable lakes. The order contains

805-416: The field of morphology was developed by Johann Wolfgang von Goethe (1790) and independently by the German anatomist and physiologist Karl Friedrich Burdach (1800). Among other important theorists of morphology are Lorenz Oken , Georges Cuvier , Étienne Geoffroy Saint-Hilaire , Richard Owen , Carl Gegenbaur and Ernst Haeckel . In 1830, Cuvier and Saint-Hilaire engaged in a famous debate , which

840-685: The grebe genera. Bochenski (1994) Podilymbus Poliocephalus Tachybaptus dominicus Tachybaptus novaehollandiae Tachybaptus ruficollis Rollandia Podiceps Podicephorus Aechmophorus Fjeldså (2004) Rollandia Tachybaptus Podilymbus Poliocephalus Podicephorus Aechmophorus Podiceps Ksepka et al. (2013) Dominicus Tachybaptus Poliocephalus Rollandia Podilymbus Podiceps nigricollis Podiceps occipitalis Podiceps auritus Podiceps cristatus Podiceps grisegena Podiceps major Aechmophorus Grebes are

875-457: The grebe-flamingo clade , the taxon Mirandornithes ("miraculous birds" due to their extreme divergence and apomorphies ) has been proposed. Alternatively, they could be placed in one order, with Phoenocopteriformes taking priority. The fossil record of grebes is incomplete as there are no transitional forms between more conventional birds and grebes known from fossils. The enigmatic waterbird genus Juncitarsus , however, may be close to

910-460: The highest among birds. The feathers are very dense and strongly curved. In the larger species feathers are more dense but shorter, while the opposite is true in smaller species where the feathers are longer but less dense. The density and length of feathers is correlated exponentially with heat-loss in cold water. For this reason grebes invest plumage maintenance the most in birds in terms of duration of time and energy. The uropygial glands secrete

945-417: The mid 16th century English as they were said to be chick-like birds that dive. The clade names "Podicipediformes" and "Podicipedidae" is based on the genus Podiceps which is a combination of Latin of podex , gen. podicis ("rear-end" or "anus") and pes ("foot"), a reference to the placement of a grebe's legs towards the rear of its body. Grebes are small to medium-large in size ranging from

980-426: The pelvic girdle. When they do fly, they often launch themselves off from the water and must run along the surface as they flap their wings to provide a lift. Bills vary from short and thick to long and pointed depending on the diet, and are slightly larger in males than in females (though the sizes can overlap between younger males and females). Grebes have unusual plumage . On average grebes have 20,000 feathers,

1015-438: The presence of long cnemial crests in the tarsometatarsus. The patella is separate and supports the tarsometatarsus posteriorly which greatly helps with the contraction in the muscles. They swim by simultaneously spreading out the feet and bringing them inward, with the webbing expanded to produce the forward thrust in much the same way as frogs. However, due to the anatomy of the legs, grebes are not as mobile on land as they are on

1050-584: The same lifestyle at different times and in different habitat. Grebes and loons are now separately classified orders of Podicipediformes and Gaviiformes, respectively. Recent molecular studies have suggested a relation with flamingos , a finding that has been backed up by morphological evidence. They hold at least eleven morphological traits in common not found in other birds. For example, both flamingoes and grebes lay eggs coated with chalky amorphous calcium phosphate. Many of these characteristics have been previously identified in flamingos, but not in grebes. For

1085-439: The secondary feathers of the wing, which varies from none in temperate northern regions, to extensive white in tropical regions. The little grebe is a small water bird with a pointed bill. The adult is unmistakable in summer, predominantly dark above with its rich, rufous colour neck, cheeks and flanks, and bright yellow gape . The rufous is replaced by a dirty brownish grey in non-breeding and juvenile birds. Juvenile birds have

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1120-407: The toes and small webs connecting the front three toes. The hind toe also has a small lobe as well. The claws are similar to nails and are flat. These lobate feet act as an oar, as when moving forward they provide minimum resistance and moving backwards they provide a coverage of maximum surface. The leg bones ( femur and tarsometatarsus ) are equal in length, with the femur having a large head and

1155-576: The use of allometric engineering in which one or both species are manipulated to phenocopy the other species. A step relevant to the evaluation of morphology between traits/features within species, includes an assessment of the terms: homology and homoplasy . Homology between features indicates that those features have been derived from a common ancestor. Alternatively, homoplasy between features describes those that can resemble each other, but derive independently via parallel or convergent evolution . The invention and development of microscopy enabled

1190-485: The water's surface. The birds build floating vegetative nests where they lay several eggs. About a third of the world's grebes are listed at various levels of conservation concerns—the biggest threats including habitat loss, the introduction of invasive predatory fish and human poaching . As such, three species have gone extinct. The word "grebe" comes from the French grèbe , which is of unknown origin and dating to 1766. It

1225-412: The water. Although they can run for a short distance, they are prone to falling over, since they have their feet placed far back on the body. The wing shape varies depending on the species, ranging from moderately long to incredibly short and rounded in shape. The wing anatomy in grebes has a relatively short and thin carpometacarpus - phalanges component which supports their primary feathers, while

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