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Sex ratio

Index Sex ratio

The sex ratio is the ratio of males to females in a population. [1]

70 relations: Alpine marmot, American alligator, Amphiprioninae, Ansley J. Coale, Arthropod, Austral Ecology, Australia, Bacteria, Bluestreak cleaner wrasse, Bride kidnapping, Canidae, Cannabaceae, Cannabis sativa, Charadriiformes, Climacteris, Cooperative breeding, Copepod, Demographic transition, Dioecy, Eric Charnov, Eusociality, Evolution of sexual reproduction, Evolutionarily stable strategy, Female, Fisher's principle, Gender Balance Council, Groom kidnapping, Hermaphrodite, Human sex ratio, Humulus japonicus, Jacanidae, JAMA (journal), Journal of Evolutionary Biology, List of countries by sex ratio, Macrotera portalis, Male, Malurus, Natural history, Nature Communications, Noisy miner, Operational sex ratio, Painted-snipe, Parrotfish, Parthenogenesis, Peafowl, Phalarope, Plover, Polistes exclamans, Polistes fuscatus, Polyandry, ..., Polygonaceae, Population, Population pyramid, Ratio, Sequential hermaphroditism, Sex allocation, Sex change, Sex selection, Sex-selective abortion, Social construction of gender, Sorrel, Southern Africa, Temperature-dependent sex determination, Trivers–Willard hypothesis, Varied sittella, W. D. Hamilton, Wasp, Wolbachia, Wrasse, XY sex-determination system. Expand index (20 more) »

Alpine marmot

The alpine marmot (Marmota marmota) is a species of marmot found in mountainous areas of central and southern Europe.

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American alligator

The American alligator (Alligator mississippiensis), sometimes referred to colloquially as a gator or common alligator, is a large crocodilian reptile endemic to the southeastern United States.

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Clownfish or anemonefish are fishes from the subfamily Amphiprioninae in the family Pomacentridae.

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Ansley J. Coale

Ansley Johnson Coale (November 14, 1917 – November 5, 2002), was one of America's foremost demographers.

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An arthropod (from Greek ἄρθρον arthron, "joint" and πούς pous, "foot") is an invertebrate animal having an exoskeleton (external skeleton), a segmented body, and paired jointed appendages.

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Austral Ecology

Austral Ecology: A Journal of Ecology in the Southern Hemisphere is a peer-reviewed journal that publishes original research related to the ecology of land, marine and freshwater systems in the Southern Hemisphere.

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Australia, officially the Commonwealth of Australia, is a sovereign country comprising the mainland of the Australian continent, the island of Tasmania and numerous smaller islands.

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Bacteria (common noun bacteria, singular bacterium) is a type of biological cell.

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Bluestreak cleaner wrasse

The bluestreak cleaner wrasse, Labroides dimidiatus, is one of several species of cleaner wrasses found on coral reefs from Eastern Africa and the Red Sea to French Polynesia.

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Bride kidnapping

Bride kidnapping, also known as marriage by abduction or marriage by capture, is a practice in which a man abducts the woman he wishes to marry.

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The biological family Canidae (from Latin, canis, “dog”) is a lineage of carnivorans that includes domestic dogs, wolves, coyotes, foxes, jackals, dingoes, and many other extant and extinct dog-like mammals.

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Cannabaceae is a small family of flowering plants.

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Cannabis sativa

Cannabis sativa is an annual herbaceous flowering plant indigenous to eastern Asia but now of cosmopolitan distribution due to widespread cultivation.

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Charadriiformes is a diverse order of small to medium-large birds.

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Climacteris is a genus of bird in the Climacteridae family.

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Cooperative breeding

Cooperative breeding is a social system characterized by alloparental care: offspring receive care not only from their parents, but also from additional group members, often called helpers.

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Copepods (meaning "oar-feet") are a group of small crustaceans found in the sea and nearly every freshwater habitat.

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Demographic transition

Demographic transition (DT) is the transition from high birth and death rates to lower birth and death rates as a country or region develops from a pre-industrial to an industrialized economic system.

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Dioecy (Greek: διοικία "two households"; adjective form: dioecious) is a characteristic of a species, meaning that it has distinct male and female individual organisms.

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Eric Charnov

Eric L. Charnov (born October 29, 1947) is an American evolutionary ecologist.

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Eusociality (from Greek εὖ eu "good" and social), the highest level of organization of animal sociality, is defined by the following characteristics: cooperative brood care (including care of offspring from other individuals), overlapping generations within a colony of adults, and a division of labor into reproductive and non-reproductive groups.

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Evolution of sexual reproduction

The evolution of sexual reproduction describes how sexually reproducing animals, plants, fungi and protists evolved from a common ancestor that was a single celled eukaryotic species.

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Evolutionarily stable strategy

An evolutionarily stable strategy (ESS) is a strategy which, if adopted by a population in a given environment, cannot be invaded by any alternative strategy that is initially rare.

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Female (♀) is the sex of an organism, or a part of an organism, that produces non-mobile ova (egg cells).

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Fisher's principle

Fisher's principle is an evolutionary model that explains why the sex ratio of most species that produce offspring through sexual reproduction is approximately 1:1 between males and females.

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Gender Balance Council

The Gender Balance Council (Arabic: مجلس الإمارات للتوازن بين الجنسين majlis al-ʾimārāt lit-tawāzun bayna al-jinsayn) is a federal entity in the UAE.

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Groom kidnapping

Groom kidnapping, colloquially known as Pakaruah shaadi or Jabaria shaadi, is a phenomenon in the western parts of Bihar, and eastern Uttar Pradesh states in India, wherein eligible bachelors are abducted by the bride's family and later forcefully married, to avoid heavy dowry costs.

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In biology, a hermaphrodite is an organism that has complete or partial reproductive organs and produces gametes normally associated with both male and female sexes.

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Human sex ratio

In anthropology and demography, the human sex ratio is the ratio of males to females in a population.

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Humulus japonicus

Humulus japonicus, known as wild hop or Japanese hop, synonym H. scandens, is an ornamental plant in the Cannabaceae family.

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The bird family Jacanidae belongs to the order Charadriiformes, and consists of 6 genera.

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JAMA (journal)

JAMA: The Journal of the American Medical Association is a peer-reviewed medical journal published 48 times a year by the American Medical Association.

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Journal of Evolutionary Biology

The Journal of Evolutionary Biology is a bimonthly peer-reviewed scientific journal covering the field of evolutionary biology.

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List of countries by sex ratio

The human sex ratio is the number of males for each female in a population.

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Macrotera portalis

Macrotera portalis is a species of communal, ground nesting, partially bivoltine bees found in arid grasslands and desert regions.

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A male (♂) organism is the physiological sex that produces sperm.

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Malurus is a genus of bird in the Australasian wren family, Maluridae.

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Natural history

Natural history is a domain of inquiry involving organisms including animals, fungi and plants in their environment; leaning more towards observational than experimental methods of study.

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Nature Communications

Nature Communications is a peer-reviewed open access scientific journal published by the Nature Publishing Group since 2010.

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Noisy miner

The noisy miner (Manorina melanocephala) is a bird in the honeyeater family, Meliphagidae, and is endemic to eastern and south-eastern Australia.

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Operational sex ratio

In the evolutionary biology of sexual reproduction, operational sex ratio (OSR) is the ratio of sexually competing males that are ready to mate to sexually competing females that are ready to mate, or alternatively the local ratio of fertilizable females to sexually active males at any given time.

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The Rostratulidae (commonly known as painted-snipes), form a taxonomic family of wader species, composed of two genera: Rostratula and Nycticryphes.

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Parrotfishes are a group of marine species found in relatively shallow tropical and subtropical oceans around the world.

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Parthenogenesis (from the Greek label + label) is a natural form of asexual reproduction in which growth and development of embryos occur without fertilization.

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The peafowl include three species of birds in the genera Pavo and Afropavo of the Phasianidae family, the pheasants and their allies.

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A phalarope is any of three living species of slender-necked shorebirds in the genus Phalaropus of the bird family Scolopacidae.

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Plovers are a widely distributed group of wading birds belonging to the subfamily Charadriinae.

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Polistes exclamans

Polistes exclamans is a social wasp and is part of the family Vespidae of the order Hymenoptera.

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Polistes fuscatus

Polistes fuscatus, whose common name is the golden or northern paper wasp, is widely found throughout southern Canada, the United States, and Central America.

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Polyandry (from πολυ- poly-, "many" and ἀνήρ anēr, "man") is a form of polygamy in which a woman takes two or more husbands at the same time.

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The Polygonaceae are a family of flowering plants known informally as the knotweed family or smartweed—buckwheat family in the United States.

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In biology, a population is all the organisms of the same group or species, which live in a particular geographical area, and have the capability of interbreeding.

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Population pyramid

A population pyramid, also called an "age-sex pyramid", is a graphical illustration that shows the distribution of various age groups in a population (typically that of a country or region of the world), which forms the shape of a pyramid when the population is growing.

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In mathematics, a ratio is a relationship between two numbers indicating how many times the first number contains the second.

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Sequential hermaphroditism

Sequential hermaphroditism (called dichogamy in botany) is a type of hermaphroditism that occurs in many fish, gastropods, and plants.

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Sex allocation

Sex allocation is the allocation of resources to male versus female reproduction in sexual species.

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Sex change

Sex change is a process by which a person or animal changes sex – that is, by which female sexual characteristics are substituted for male ones, or vice versa.

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Sex selection

Sex selection is the attempt to control the sex of the offspring to achieve a desired sex.

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Sex-selective abortion

Sex-selective abortion is the practice of terminating a pregnancy based upon the predicted sex of the infant.

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Social construction of gender

The social construction of gender is a belief in feminism and sociology about the operation of gender and gender differences in societies.

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Common sorrel or garden sorrel (Rumex acetosa), often simply called sorrel, is a perennial herb in the family Polygonaceae.

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Southern Africa

Southern Africa is the southernmost region of the African continent, variably defined by geography or geopolitics, and including several countries.

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Temperature-dependent sex determination

Temperature-dependent sex determination (TSD) is a type of environmental sex determination in which the temperatures experienced during embryonic/larval development determine the sex of the offspring.

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Trivers–Willard hypothesis

In evolutionary biology and evolutionary psychology, the Trivers–Willard hypothesis, formally proposed by Robert Trivers and Dan Willard, suggests that female mammals are able to adjust offspring sex ratio in response to their maternal condition.

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Varied sittella

The varied sittella (Daphoenositta chrysoptera) is a small, around 10–11 cm long, songbird native to Australia and New Guinea.

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W. D. Hamilton

William Donald Hamilton, FRS (1 August 1936 – 7 March 2000) was an English evolutionary biologist, widely recognised as one of the most significant evolutionary theorists of the 20th century.

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A wasp is any insect of the order Hymenoptera and suborder Apocrita that is neither a bee nor an ant.

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Wolbachia is a genus of Gram-negative bacteria which infects arthropod species, including a high proportion of insects, but also some nematodes.

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The wrasses are a family, Labridae, of marine fish, many of which are brightly colored.

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XY sex-determination system

The XY sex-determination system is the sex-determination system found in humans, most other mammals, some insects (Drosophila), some snakes, and some plants (Ginkgo).

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Redirects here:

Adult sex ratio, Birth ratio, Birth sex ratio, Gender balance, Gender ratio, Sex Ratio, Sex ratios, Unbalanced sex ratio.


[1] https://en.wikipedia.org/wiki/Sex_ratio

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