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Phoca Vitulina Terschelling.jpg
''Phoca'' ( ) is a genus of the earless seals, within the family Phocidae, source of the French name for seal, 'phoque'. It now contains just two species, the common seal (or harbour seal) and the spotted seal (or largha seal). Several species formerly listed under this genus have been split into the genera ''Pusa'', '' Pagophilus'', and '' Histriophoca''. Until recently, ''Phoca largha'' has been considered a subspecies of ''Phoca vitulina'' but now is considered its own species. For this reason, the fossil history of the genus is unclear, and it has formerly been used as wastebasket taxon for a number of fossils of uncertain affinity. Species Currently there are two members: Former members of ''Phoca'': * ''Histriophoca fasciata'' (ribbon seal) * ''Pusa caspica'' (Caspian seal) * ''Pusa hispida'' (ringed seal) * ''Pusa sibirica'' (nerpa or Baikal seal) * ''Pagophilus groenlandica'' (harp seal) Mating ecology Both harbour and spotted seals are aquatically mating pinnipeds. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carl Linnaeus
Carl Linnaeus (; 23 May 1707 – 10 January 1778), also known after his Nobility#Ennoblement, ennoblement in 1761 as Carl von Linné#Blunt, Blunt (2004), p. 171. (), was a Swedish botanist, zoologist, taxonomist, and physician who formalised binomial nomenclature, the modern system of naming organisms. He is known as the "father of modern Taxonomy (biology), taxonomy". Many of his writings were in Latin; his name is rendered in Latin as and, after his 1761 ennoblement, as . Linnaeus was born in Råshult, the countryside of Småland, in southern Sweden. He received most of his higher education at Uppsala University and began giving lectures in botany there in 1730. He lived abroad between 1735 and 1738, where he studied and also published the first edition of his ' in the Netherlands. He then returned to Sweden where he became professor of medicine and botany at Uppsala. In the 1740s, he was sent on several journeys through Sweden to find and classify plants and animals. In ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ringed Seal
The ringed seal (''Pusa hispida'') is an earless seal inhabiting the Arctic and sub-Arctic regions. The ringed seal is a relatively small seal, rarely greater than 1.5 m in length, with a distinctive patterning of dark spots surrounded by light gray rings, hence its common name. It is the most abundant and wide-ranging ice seal in the Northern Hemisphere, ranging throughout the Arctic Ocean, into the Bering Sea and Okhotsk Sea as far south as the northern coast of Japan in the Pacific and throughout the North Atlantic coasts of Greenland and Scandinavia as far south as Newfoundland, and including two freshwater subspecies in northern Europe. Ringed seals are one of the primary prey of polar bears and killer whales, and have long been a component of the diet of indigenous people of the Arctic. Ringed seals are the smallest and most abundant member of the seal family that live in the Arctic and Sub-Arctic regions. The average life span of a ringed seal is 40 years, with a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monogamy
Monogamy ( ) is a form of dyadic relationship in which an individual has only one partner during their lifetime. Alternately, only one partner at any one time (serial monogamy) — as compared to the various forms of non-monogamy (e.g., polygamy or polyamory). The term is also applied to the social behavior of some animals, referring to the state of having only one mate at any one time. A monogamous relationship can be sexual or emotional, but it's usually both. Many modern relationships are monogamous. Terminology The word '' monogamy'' derives from the Greek μονός, ''monos'' ("alone"), and γάμος, ''gamos'' ("marriage").Cf. "Monogamy" in ''Britannica World Language Dictionary'', R.C. Preble (ed.), Oxford-London 1962, p. 1275:''1. The practice or principle of marrying only once. opp. to digamy now ''rare'' 2. The condition, rule or custom of being married to only one person at a time (opp. to polygamy or bigamy) 1708. 3. Zool. The habit of living in pairs, or h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sexual Selection
Sexual selection is a mode of natural selection in which members of one biological sex choose mates of the other sex to mate with (intersexual selection), and compete with members of the same sex for access to members of the opposite sex (intrasexual selection). These two forms of selection mean that some individuals have greater reproductive success than others within a population, for example because they are more attractive or prefer more attractive partners to produce offspring. Successful males benefit from frequent mating and monopolizing access to one or more fertile females. Females can maximise the return on the energy they invest in reproduction by selecting and mating with the best males. The concept was first articulated by Charles Darwin who wrote of a "second agency" other than natural selection, in which competition between mate candidates could lead to speciation. The theory was given a mathematical basis by Ronald Fisher in the early 20th century. Sex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hauling-out
Hauling-out is a behaviour associated with pinnipeds ( true seals, sea lions, fur seals and walruses) temporarily leaving the water. Hauling-out typically occurs between periods of foraging activity. Rather than remain in the water, pinnipeds haul-out onto land or sea-ice for reasons such as reproduction and rest. Hauling-out is necessary in seals for mating (with the exception of the Baikal seal) and giving birth (although a distinction is generally made between reproductive aggregations, termed " rookeries", and non-reproductive aggregations, termed "haul-outs"). Other benefits of hauling-out may include predator avoidance, thermoregulation, social activity, parasite reduction and rest. There is much variation in haul-out patterns among different seal species.Hoelzel, A. Rus. (2002). ''Marine Mammal Biology: An Evolutionary Approach''. Blackwell Publishing. . p. 197. Haul-out sites may be segregated by age and sex within the same species. Many species of pinniped have only ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lek Mating
A lek is an aggregation of male animals gathered to engage in competitive displays and courtship rituals, known as lekking, to entice visiting females which are surveying prospective partners with which to mate. A lek can also indicate an available plot of space able to be utilized by displaying males to defend their own share of territory for the breeding season. A lekking species is characterised by male displays, strong female mate choice, and the conferring of indirect benefits to males and reduced costs to females. Although most prevalent among birds such as black grouse, lekking is also found in a wide range of vertebrates including some bony fish, amphibians, reptiles, and mammals, and arthropods including crustaceans and insects. A classical lek consists of male territories in visual and auditory range of each other. An exploded lek, as seen in the kakapo (the owl parrot), has more widely separated territories, but still in auditory range. Lekking is associated ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polygynous Animal Mating
Polygyny (; from Neo-Greek πολυγυνία, from πολύ- ''poly-'', "many", and γυνή ''gyne'', "woman" or "wife") is a mating system in which one male lives and mates with multiple females but each female only mates with a single male. Systems where several females mate with several males are defined either as promiscuity or polygynandry. Lek mating is frequently regarded as a form of polygyny, because one male mates with many females, but lek-based mating systems differ in that the male has no attachment to the females with whom he mates, and that mating females lack attachment to one another.Clutton-Brock T.H. (1989). ‘Review lecture: mammalian mating systems.' ''Proceedings of the Royal Society of London''. Series B, Biological Sciences 236: 339–372. Polygyny is typical of one-male, multi-female groupsBoyd, R., & Silk, J. B. (2009). How Humans Evolved (preferably the downloadable pdf version): WW Norton & Company, New York. and can be found in many species includi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Estrous Cycle
The estrous cycle (, originally ) is the set of recurring physiological changes that are induced by reproductive hormones in most mammalian therian females. Estrous cycles start after sexual maturity in females and are interrupted by anestrous phases, otherwise known as "rest" phases, or by pregnancies. Typically, estrous cycles repeat until death. These cycles are widely variable in duration and frequency depending on the species.Bronson, F. H., 1989. Mammalian Reproductive Biology. University of Chicago Press, Chicago, IL, USA. Some animals may display bloody vaginal discharge, often mistaken for menstruation. Many mammals used in commercial agriculture, such as cattle and sheep, may have their estrous cycles artificially controlled with hormonal medications for optimum productivity. The male equivalent, seen primarily in ruminants, is called rut. Differences from the menstrual cycle Mammals share the same reproductive system, including the regulatory hypothalamic s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pinniped
Pinnipeds (pronounced ), commonly known as seals, are a widely range (biology), distributed and diverse clade of carnivorous, fin-footed, semiaquatic, mostly marine mammal, marine mammals. They comprise the extant taxon, extant family (biology), families Odobenidae (whose only living member is the walrus), Otariidae (the eared seals: sea lions and fur seals), and Phocidae (the earless seals, or true seals). There are 34 extant species of pinnipeds, and more than 50 extinct species have been described from fossils. While seals were historically thought to have descended from two ancestral lines, molecular phylogenetics, molecular evidence supports them as a monophyletic lineage (descended from one ancestral line). Pinnipeds belong to the order Carnivora; their closest living relatives are Musteloidea, musteloids (Mustelidae, weasels, Procyonidae, raccoons, skunks, and red pandas), having diverged about 50 million years ago. Seals range in size from the and Baikal sea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Harbour Seal Breast Feeding 1150144
A harbor (American English), harbour (British English; see spelling differences), or haven is a sheltered body of water where ships, boats, and barges can be docked. The term ''harbor'' is often used interchangeably with ''port'', which is a man-made facility built for loading and unloading vessels and dropping off and picking up passengers. Ports usually include one or more harbors. Alexandria Port in Egypt is an example of a port with two harbors. Harbors may be natural or artificial. An artificial harbor can have deliberately constructed breakwaters, sea walls, or jettys or they can be constructed by dredging, which requires maintenance by further periodic dredging. An example of an artificial harbor is Long Beach Harbor, California, United States, which was an array of salt marshes and tidal flats too shallow for modern merchant ships before it was first dredged in the early 20th century. In contrast, a natural harbor is surrounded on several sides of land. Examples ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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