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Penguin Books People
Penguins are a group of aquatic flightless birds from the family Spheniscidae () of the order Sphenisciformes (). They live almost exclusively in the Southern Hemisphere. Only one species, the Galápagos penguin, is equatorial, with a small portion of its population extending slightly north of the equator (within a quarter degree of latitude). Highly adapted for life in the ocean water, penguins have countershaded dark and white plumage and flippers for swimming. Most penguins feed on krill, fish, squid and other forms of sea life which they catch with their bills and swallow whole while swimming. A penguin has a spiny tongue and powerful jaws to grip slippery prey. They spend about half of their lives on land and the other half in the sea. The largest living species is the emperor penguin (''Aptenodytes forsteri''): on average, adults are about tall and weigh . The smallest penguin species is the little blue penguin (''Eudyptula minor''), also known as the fairy pengui ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Danian
The Danian is the oldest age or lowest stage of the Paleocene Epoch or Series, of the Paleogene Period or System, and of the Cenozoic Era or Erathem. The beginning of the Danian (and the end of the preceding Maastrichtian) is at the Cretaceous–Paleogene extinction event . The age ended , being followed by the Selandian. Stratigraphic definitions The Danian was introduced in scientific literature by German-Swiss geologist Pierre Jean Édouard Desor in 1847 following a study of fossils found in France and Denmark.Danien Den Store Danske Encyklopædi He identified this stage in deposits from [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pygoscelis
The genus ''Pygoscelis'' ("rump-legged") contains three living species of penguins collectively known as "brush-tailed penguins". Taxonomy Mitochondrial and nuclear DNA evidence suggests the genus split from other penguins around 38 million years ago, about 2 million years after the ancestors of the genus '' Aptenodytes''. In turn, the Adelie penguins split off from the other members of the genus around 19 million years ago. ;Extant species A 2020 study found that the gentoo penguin may actually comprise a species complex of 4 similar but genetically distinct species: the northern gentoo penguin (''P. papua''), the southern gentoo penguin (''P. ellsworthi''), the eastern gentoo penguin (''P. taeniata''), and the newly-described South Georgia gentoo penguin (''P. poncetii''). However, in 2021 the International Ornithological Congress recognized these as being subspecies In Taxonomy (biology), biological classification, subspecies (: subspecies) is a rank b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plumage
Plumage () is a layer of feathers that covers a bird and the pattern, colour, and arrangement of those feathers. The pattern and colours of plumage differ between species and subspecies and may vary with age classes. Within species, there can be different colour morph (zoology), morphs. The placement of feathers on a bird is not haphazard but rather emerges in organized, overlapping rows and groups, and these are known by standardized names. Most birds moult twice a year, resulting in a breeding or ''nuptial plumage'' and a ''basic plumage''. Many ducks and some other species such as the red junglefowl have males wearing a bright nuptial plumage while breeding and a drab ''eclipse plumage'' for some months afterward. The painted bunting's juveniles have two inserted moults in their first autumn, each yielding plumage like an adult female. The first starts a few days after fledging replacing the ''juvenile plumage'' with an ''auxiliary formative plumage''; the second a month o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Countershading
Countershading, or Thayer's law, is a method of camouflage in which animal coloration, an animal's coloration is darker on the top or upper side and lighter on the underside of the body. This pattern is found in many species of mammals, reptiles, birds, fish, and insects, both in predators and in prey. When light falls from above on a uniformly coloured three-dimensional object such as a sphere, it makes the upper side appear lighter and the underside darker, grading from one to the other. This pattern of light and shade makes the object appear solid, and therefore easier to detect. The classical form of countershading, discovered in 1909 by the artist Abbott Handerson Thayer, works by counterbalancing the effects of self-shadowing, again typically with grading from dark to light. In theory this could be useful for military camouflage, but in practice it has rarely been applied, despite the best efforts of Thayer and, later, in the Second World War, of the zoologist Hugh Cott. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galápagos Penguin
The Galápagos penguin (''Spheniscus mendiculus'') is a penguin Endemism, endemic to the Galápagos Islands of Ecuador. It is the only penguin found north of the equator. Most inhabit Fernandina Island and the west coast of Isabela Island (Galápagos), Isabela Island. The cool waters of the Humboldt Current, Humboldt and Cromwell Currents allow it to survive despite the tropical latitude. The Galápagos penguin is one of the banded penguins, the other species of which live mostly on the coasts of Africa and mainland South America. Due to their warm environment, Galápagos penguins have developed techniques to stay cool. The feathers on their back, flippers, and head are black, and they have a white belly and a stripe looping from their eyes down to their neck and chin. Each penguin keeps only one mate, and breeds year-round. Because there is no soft areas to nest, their nests are typically in caves and crevices which also provide protection against predators and the harsh enviro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), classification and a taxonomic rank of an organism, as well as a unit of biodiversity. Other ways of defining species include their karyotype, DNA sequence, morphology (biology), morphology, behaviour, or ecological niche. In addition, palaeontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. About 14% of these had been described by 2011. All species (except viruses) are given a binomial nomenclature, two-part name, a "binomen". The first part of a binomen is the name of a genus to which the species belongs. The second part is called the specific name (zoology), specific name or the specific ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Order (biology)
Order () is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between family and class. In biological classification, the order is a taxonomic rank used in the classification of organisms and recognized by the nomenclature codes. An immediately higher rank, superorder, is sometimes added directly above order, with suborder directly beneath order. An order can also be defined as a group of related families. What does and does not belong to each order is determined by a taxonomist, as is whether a particular order should be recognized at all. Often there is no exact agreement, with different taxonomists each taking a different position. There are no hard rules that a taxonomist needs to follow in describing or recognizing an order. Some taxa are accepted almost universally, while others are recognized only rarely. The name of an order is usually written with a capital letter. For some groups of organisms, their orders may follow consist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Family (biology)
Family (, : ) is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between order and genus. A family may be divided into subfamilies, which are intermediate ranks between the ranks of family and genus. The official family names are Latin in origin; however, popular names are often used: for example, walnut trees and hickory trees belong to the family Juglandaceae, but that family is commonly referred to as the "walnut family". The delineation of what constitutes a family—or whether a described family should be acknowledged—is established and decided upon by active taxonomists. There are not strict regulations for outlining or acknowledging a family, yet in the realm of plants, these classifications often rely on both the vegetative and reproductive characteristics of plant species. Taxonomists frequently hold varying perspectives on these descriptions, leading to a lack of widespread consensus within the scientific community ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flightless Bird
Flightless birds are birds that cannot Bird flight, fly, as they have, through evolution, lost the ability to. There are over 60 extant species, including the well-known ratites (ostriches, emus, cassowary, cassowaries, Rhea (bird), rheas, and Kiwi (bird), kiwis) and penguins. The smallest flightless bird is the Inaccessible Island rail (length 12.5 cm, weight 34.7 g). The largest (both heaviest and tallest) flightless bird, which is also the largest living bird in general, is the common ostrich (2.7 m, 156 kg). Many domesticated birds, such as the domestic chicken and domestic duck, have lost the ability to fly for extended periods, although their ancestral species, the red junglefowl and mallard, respectively, are capable of extended flight. A few particularly bred birds, such as the Broad Breasted White turkey, have become totally flightless as a result of selective breeding; the birds were bred to grow massive breast meat that weighs too much for the bird's wings ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Water Bird
A water bird, alternatively waterbird or aquatic bird, is a bird that lives on or around water. In some definitions, the term ''water bird'' is especially applied to birds in freshwater ecosystems, although others make no distinction from seabirds that inhabit marine environments. Some water birds (e.g. wading birds) are more terrestrial while others (e.g. waterfowls) are more aquatic, and their adaptations will vary depending on their environment. These adaptations include webbed feet, beaks, and legs adapted to feed in the water, and the ability to dive from the surface or the air to catch prey in water. The term ''aquatic bird'' is sometimes also used in this context. A related term that has a narrower meaning is waterfowl. Some piscivorous birds of prey, such as ospreys, sea eagles, fish eagles, fish owls, and fishing owls, hunt aquatic prey but do not stay in water for long and live predominantly over dry land, and are not considered water birds. The term waterbird ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Penguins
Penguin, Penguins are birds in the Family (biology), family Spheniscidae in the Monotypic taxon, monotypic Order (biology), order Sphenisciformes. They inhabit high-productivity marine habitats, almost exclusively in the Southern Hemisphere; the only species to occur north of the Equator is the Galapagos penguin. The only group of birds other than the ratites to be entirely flightless, penguins are extremely adapted to their aquatic lifestyle, with a streamlined shape that minimizes drag, Countershading, countershaded dark-and-white plumage, dense bones, powerful flippers, and insulating feathers that allow them to withstand very low temperatures on land and in water. There are currently 18 extant species of penguins recognised by the International Ornithologists' Union, distributed among six genera. Many species of fossil penguins are known from the Paleocene onwards; however, their exact number and taxonomy are unsettled due to ongoing discoveries. Conventions Conservatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
