main article effective population size In population genetics an idealisedpopulation , also sometimes called a Fisher Wright population after Ronald Fisher R.A. Fisher and Sewall Wright , is a population whose members can Sexual intercourse mate and reproduce with any other member of the other gender, has a sex ratio of 1 and no overlapping generations. As such, each individual has the same chance to contribute its own genetic material to the next generation no selection . Deviation from the idealisedpopulation results in the effective population size being smaller than the total population size. evolution stub statistics stub Category Population genetics Category Statistical genetics ... more details
Other uses pp move indef File Population density.png thumb 350px Distribution of world population in 1994. File Population density key.png thumb 150px Key A population is all the organisms that both belong to the same group or species and live in the same geographical area . In ecology the population ... to define a sex ual population is such that interbreeding inter breeding is possible between any pair ... first Daniel authorlink title Principles of Population Genetics publisher Sinauer Associates series year 2007 doi isbn 978 0 87893 308 2 page 45 ref In sociology , population refers to a collection .... This article refers mainly to human population. Population genetics In population genetics a sex ual population is a set of organisms in which any pair of members can Breeding in the wild breed ... last Hartl first Daniel authorlink title Principles of Population Genetics publisher Sinauer Associates series year 2007 doi isbn 978 0 87893 308 2 page 95 ref . World human population Main World population As of today s date, the world population is estimated by the United States Census Bureau to be expr ... on 12 March 2012. According to a separate estimate by the United Nations, Earth s population ... to all of humanity, according to UNFPA , the United Nations Population Fund. ref http www.unfpa.org ... to papers published by the United States Census Bureau , the world population hit 6.5 billion 6,500,000,000 on 24 February 2006. The United Nations Population Fund designated 12 October 1999 as the approximate day on which world population reached 6 billion. This was about 12 years after world population reached 5 billion in 1987, and 6 years after world population reached 5.5 billion in 1993. The population of some countries, such as Nigeria , is not even known to the nearest million, ref ... 2005 Population Estimates MongaBay.com accessdate 1 July 2008 ref so there is a considerable ... born in the last 2000 years. ref Haub, C. 1995 2004. How Many People Have Ever Lived On Earth? Population ... more details
Population structure may refer to many aspects of population ecology Population stratification Population pyramid Age class structure F statistics Population density Population distribution Population dynamics and population growth Population genetics Population size disambig ... more details
Wiktionary Population may refer to Population human populations List of countries by population World PopulationPopulation biology , the biological study of animal populations Statistical population Metallicity , star populations Population album , an album by The Most Serene Republic Population control See also People disambiguation disambig an Poblaci n de Population es Poblaci n desambiguaci n eu Populazio argipena hr Populacija it Popolazione disambigua lv Popul cija nl Populatie pl Populacja ro Popula ie dezambiguizare sk Popul cia sv Population olika betydelser ... more details
Population genomics is the large scale comparison of DNA sequences of populations. Population genomics is a neologism that is associated with population genetics . See also Genomics Personal genomics Population groups in biomedicine References http hmg.oxfordjournals.org cgi content full 10 20 2199 Population genomics a bridge from evolutionary history to genetic medicine http arjournals.annualreviews.org doi abs 10.1146 annurev.ento.46.1.441 POPULATION GENOMICS Genome Wide Sampling of Insect Populations Category Genomics genetics stub ko ... more details
Population count may refer to A census , the process of obtaining information about every member of a population not necessarily a human population Hamming weight , the number of non zero entries 1 bits in a in a byte, string, word, array or other similar data structure disambig ... more details
The term population reduction may be used in relation to many topics, including the following population decline or depopulation reductions in human population levels for reasons such as low birth rate, emigration, disease or war. population control deliberate attempts to control human population levels typically seeking an initial reduction as opposed to an increase , sometimes related to the Optimum Population concept. culling deliberate reductions in animal or plant population levels, by human action population reduction the phase preceding the extinction of a species the Population reduction theory a theory involving genocide disambiguation ... more details
Unreferenced stub auto yes date December 2009 In population genetics and population ecology , population size usually denoted N is the number of individual organism s in a population . The effective population size N sub e sub is defined as the number of breeding individuals in an idealized population that would show the same amount of dispersion of allele frequencies under random genetic drift or the same amount of inbreeding as the population under consideration. N sub e sub is usually less than N the absolute population size and this has important applications in conservation genetics . Small population size results in increased genetic drift . Population bottleneck s are when population size reduces for a short period of time. Overpopulation may indicate any case in which the population of any species of animal may exceed the carrying capacity of its ecological niche . See also Holocene extinction event Population growth rate Overpopulation Carrying capacity Ecology stub modelling ecosystems expanded other DEFAULTSORT Population Size Category Ecological metrics Category Population genetics cs Po et obyvatel de Einwohnerzahl et Rahvaarv is Stofnst r ru sk Po et obyvate ov fi Populaatiokoko ... more details
refimprove date November 2011 Population momentum refers to population growth at the national level which ..., Heuveline, and Guillot 2001 Demography Measuring and Modeling Population Processes ref For countries with above replacement fertility greater than 2.1 children per woman , population momentum represents natural increase to the population. For below replacement countries, momentum corresponds to a population ... currently bearing children, which impacts the immediate birth and death rates in the population which determine the intrinsic rate of growth. Formal demographers refer to population momentum as the size of the resulting stationary equivalent population relative to the current size of the population. Population momentum has implications for population policy for a number of reasons. First with respect to high fertility countries in the developing world , population momentum instructs us that these countries ... population decline even if they bring their fertility levels up to replacement. In fact, population ..., for example, some Eastern European countries would show population shrinkage even if their birth rates recovered to replacement level. Finally, population momentum shows us that replacement level fertility is a long term concept rather than an indication of current population growth rates. Depending ... short term growth or decline. Calculation To calculate population momentum for population A, a theoretical population is constructed in which the birth rate for population A immediately becomes replacement level. Under such conditions, the population will eventually stabilize into a stationary population, with no year to year changes in age specific rates or in total population. The population momentum is calculated by dividing this final total population number by the starting population. ref Preston, Heuveline, and Guillot 2001 Demography Measuring and Modeling Population Processes, 165 ref Countries with a Population momentum The following list are countries that maintain growth despite ... more details
unreferenced date November 2010 notability date November 2010 Population Connection is an organization in the United States, formerly known as Zero Population Growth . They adopted their current name in 2002. Zero Population Growth was originally founded in 1968 by Paul R. Ehrlich , Richard Bowers , and Charles Remington , in the wake of the impact from Ehrlich s best selling book, The Population Bomb . Population Connection started educating young people nearly forty years ago with their Population Education program. They also advocate for action to stabilize the world population through voluntary measures, primarily through increased access to reproductive health services and supplies. Their mission statement is as follows blockquote Overpopulation threatens the quality of life for people everywhere. Population Connection is the national grassroots population organization that educates young people and advocates progressive action to stabilize world population at a level that can be sustained by Earth s resources. blockquote Population Connection has 30,000 members who provide the majority of the organization s revenue. The organization s headquarters is in Washington, D.C. Population Connection works on issues concerning overpopulation , the environment, poverty, and reproductive rights , and publishes a tri annual magazine, The Reporter . Population Connection supporters live ... needs urging to vote in favor of measures that reduce population growth. The three districts are in the suburbs of Seattle, WA Columbus, OH and Minneapolis, MN. Double the Money is Population ... States appropriated 545 million for FY2009. Population Connection lobbies to end federal funding for abstinence only sex education programs in the United States. See also Overpopulation Population Control External links Official http www.populationconnection.org Population Category Political advocacy groups in the United States Category Sustainability organisations Category Population organizations ... more details
Original research date September 2007 Refimprove date August 2009 The optimum population is the size of a population that is optimal. There are, however, various opinions on what optimal means in this usage, resulting in various end targets for it, ref cite doi 10.1007 BF02211719 ref but estimations usually take ecological sustainability and carrying capacity more or less into account. Also, optimum population can refer to a specific area, such as a region or country, but can also refer to the entire world or universe . For humans Regarding the human population , end targets for an optimum population ... Population P. S. Dasgupta The Review of Economic Studies Vol. 36, No. 3 Jul., 1969 , pp. 295 318 ... disagree with the concept of optimum population , believing that the human population will always, in the long term, be able to adapt to the requirements of a larger population. ref name nyt19980212 ... predictions, even if it could theoretically exist. To reach an optimum population, a country ... among other factors. Reaching optimum population is an important objective in the wider project ... the optimum human population, and different emphasis on different end targets cause variability among estimates. The optimal world population has been estimated by a team co authored by Paul ... dieoff.org page99.htm Optimum Human Population Size . Population and Environment A Journal of Interdisciplinary ... Preservation of biodiversity Based on this, the estimation of optimum population was to be roughly around 1.5 billion to 2 billion people. ref name Ehrlichetal1994 The UK based think tank Population Matters , formerly known as the Optimum Population Trust , has calculated the optimum population of nearly 150 countries. ref http www.optimumpopulation.org opt.sustainable.numbers.html Optimum Population ... rate Organisations Population Matters formerly Optimum Population Trust Sustainable Population Australia References references Population Category Population Category Demography es ptimo de poblaci n ... more details
Image Population density.png thumb 300px Map of world population density as of 1994. Unreferenced date October 2009 Population geography is a division of human geography . It is the study of the ways in which spatial variations in the distribution, composition, migration, and growth of populations are related to the nature of places. Population geography involves demography in a geographical perspective. It focuses on the characteristics of population distributions that change in a spatial context. Examples can be shown through population density maps. A few types of maps that show the spatial layout of population are choropleth , isoline , and dot maps. Population geography studies Demographic phenomena natality, mortality, growth rates, etc through both space and time Increase or decrease in population numbers The movements and mobility of populations Occupational Structure The way in which places in turn react to population phenomena e.g. immigration Research topics of other geographic sub disciplines, such as settlement geography , have also a population geographic dimension Grouping of people in settlements The way from the geographical character of places e.g. settlement patterns All of the above are looked at over space and time. Notes Reflist N.B. The boundary between population geography and demography is becoming more and more blurred. Human geography DEFAULTSORT Population Geography Category Demography Category Human geography Category Population Geo term stub ar ca Geografia de la poblaci de Bev lkerungsgeografie et Rahvastikugeograafia es Geograf a de la poblaci n fr G ographie de la population hr Populacijska geografija ka nl Bevolkingsgeografie ja pl Geografia ludno ci pt Geografia populacional si sr sh Populacijska geografija fi V est maantiede uk zh ... more details
Image Countries by population density.svg 300px thumb Population density people per km sup 2 sup by country, 2006 File World population density 1994.png thumb right 300px Population density people per km sup 2 sup map of the world in 1994 detailed . Image Population density with key.png thumb right 300px Population density people per km sup 2 sup map of the world in 1994. Population density in agriculture standing stock and standing crop is a measurement of population per unit area or unit volume ... Population Density . Geography.about.com. March 2 2011. Retrieved on 2011 12 10. ref Biological population densities Population density is population divided by total land area. ref name about Low densities ... effect after the scientist who identified it. Examples of the causes in low population densities include ref http www.eoearth.org article Minimum viable population size Minimum viable population size ... species commonly have high population densities, while K selection K selected species may have ... pollinators, as found in the orchid family Orchidaceae . Human population density This section is linked from List of countries by population density Image Monaco by night.JPG thumb Monaco .... File EU Pop2008 1024.PNG thumb A population cartogram uses areas rather than colors to represent population density. main List of sovereign states and dependent territories by population density For humans , population density is the number of people per unit of area usually per square kilometer or mile ... for a county , list of cities by population density city , country , another territory country subdivision territory , or the Earth entire world . The world s population is 7 billion, ref http www.census.gov main www popclock.html U.S. & World Population Clocks . Census.gov. Retrieved on 2011 ... . CIA World Handbook ref Therefore the worldwide human population density is 6.8 billion 510 million ... 2 sup 58 million sq. miles is taken into account, then human population density increases to 45.3 per ... more details
A population cycle in zoology is a phenomenon where population s rise and fall over a predictable period of time. There are some species where population numbers have reasonably predictable patterns of change although the full reasons for population cycles is one of the major unsolved ecological problems. There are a number of factors which influence population change such as availability of food, predators, diseases and climate. Occurrence in mammal populations Olaus Magnus , the Archbishop of Uppsala in central Sweden, identified that species of northern rodent s had periodic peaks in population and published two reports on the subject in the middle of the 16th century. In North America, the phenomenon was identified in populations of the Snowshoe Hare snowshoe hare . In 1865, trappers with the Hudson s Bay Company were catching plenty of animals. By 1870, they were catching very few. It was finally .... The most well known example of creatures which have a population cycle is the lemming . The biologist ... cycles of population growth and decline. When their population outgrows the resources of their habitat ... Grouse ruffed grouse . There are other species which have irregular population explosions such as Caelifera ... and predators. As the population expands, there is more food available for predators. As it contracts, there is less food available for predators, putting pressure on their population numbers. References ... SnowshoeHareCycles.pdf National Parks Service Document on population cycles http www.cas.uio.no Publications ... Encyclop dia Britannica Online 25 August 2005 Population Ecology article section on Population Cycles Errki Korpimaki and Charles J Krebs Predation and Population Cycles of Small Mammals Bioscience November 1996 Volume 46, Number 10 Further reading Alan Berryman, Population Cycles , Oxford University Press US, 2002 ISBN 0 19 514098 2 See also Population dynamics modelling ecosystems expanded other Category Population eo Populaciciklo ... more details
In the various fields of healthcare, a population study is a study of a group of individuals taken from the general population who share a common characteristic, such as age, sex , or health condition. This group may be studied for different reasons, such as their response to a drug or risk of getting a disease. External links http www.cancer.gov Templates db alpha.aspx?CdrID 561718 Population study entry in the public domain NCI Dictionary of Cancer Terms NCI cancer dict health stub Category Clinical research ... more details
Population ethics is the philosophy philosophical study of the ethics ethical problems concerning population . See also Average and total utilitarianism Mere addition paradox Overpopulation External links http www.repugnant conclusion.com index.html Population Ethics, Aggregate Welfare, and the Repugnant Conclusion http plato.stanford.edu entries repugnant conclusion The Repugnant Conclusion in the Stanford Encyclopedia of Philosophy philosophy stub Category Demography Category Ethics ... more details
Population projection , in the field of demography , is an estimate of a future population. In contrast with intercensal estimates and censuses, which usually involve some sort of field data gathering, projections usually involve mathematical models based only on pre existing data. A projection may be made by a governmental organization, or by those unaffiliated with a government. See also Census Unreferenced date November 2010 DEFAULTSORT Population Projection Category Demography statistics stub fr Projection d mographique kk lt Demografin prognoz ru ... more details
Infobox journal title Population & Environment cover image Population and Environment Cover.jpg abbreviation Popul. Environ. discipline Environmental science Environmental and social sciences editor Lori M. Hunter publisher Springer Science Business Media country frequency Quarterly history 1978 present impact 1.000 impact year 2010 website http www.springer.com social sciences population studies journal 11111 link1 http www.springerlink.com openurl.asp?genre issue&issn 0199 0039&issue current link1 name Online access ISSN 1573 7810 LCCN 80648697 CODEN PENVDK OCLC 05511021 Population & Environment is a Peer review peer reviewed academic journal covering research on the bi directional links between population, natural resources, and the natural environment. The editor in chief is Lori M. Hunter University of Colorado at Boulder . External links Official http www.springer.com social sciences population studies journal 11111 sci journal stub Category Environmental social science journals Category Springer academic journals Category Publications established in 1978 Category English language journals Category Quarterly journals ... more details
No footnotes date April 2009 Population dynamics is the branch of life sciences that studies short term and long term changes in the size and age composition of population s, and the biology biological and environment biophysical environmental processes influencing those changes. Population dynamics ... and emigration , and studies topics such as ageing population s or population decline . One common mathematical model for population dynamics is the exponential growth model. ref http www.sosmath.com diffeq first application population population.html ref With the exponential model, the rate of change of any given population is proportional to the already existing population. ref http www.sosmath.com diffeq first application population population.html ref History Population dynamics has traditionally ... of population dynamics is widely regarded as the exponential law of Malthus , as modelled by the Malthusian ... and the MMORPG Ultima Online , among others, tried to computer simulation simulate some of these population dynamics. In the past 30 years, population dynamics has been complemented by evolutionary ... may take a deterministic mathematical form. Population dynamics overlap with another active area .... Fisheries and wildlife management seealso Population dynamics of fisheries Matrix population models In fisheries and wildlife management , population is affected by three dynamic rate functions. Natality .... Usually refers to the age a fish can be caught and counted in nets Population growth rate , which measures the growth of individuals in size and length. More important in fisheries, where population ... over many time intervals, we can determine how a population s density changes over time. Immigration ... the harvestable surplus, which is the number of individuals that can be harvested from a population without affecting long term stability, or average population size. The harvest within the harvestable ... good and evil of population management, for example, in deer, the DNR are trying to reduce deer ... more details
No footnotes date July 2011 Population statistics is the use of statistics to analyze characteristics or changes to a population. It is related to Social Demography social demography and demography . Population statistics can analyze anything from global demographic changes to local small scale changes. For example, an analysis of global change shows that population growth has slowed, infant mortality rates have declined and there have been small increases in the aged. Collection National population ... adjusted to produce census estimates that identify such statistics as resident population , residents ... count. Between censuses, administrative data collected by various agencies about population events ... s. Population estimates and projections Population estimates are usually derived from census and other administrative data. Population estimates are normally produced after the date the estimate is for. Some estimates, such as the Usually resident population estimate who usually lives in a locality ... with estimating population on a particular date that is different to the census date, for example ... and migration data to adjust census counts for the changes that have happened since the census. Population ... of existing census data and other sources of population information to forecast the size of future populations. Because there are unknown factors that may affect future population changes, population projections often incorporate high and low as well as expected values for future populations. Population ... were conducted in antiquity, there are few population statistics that survive. One example though ... to determine not only what was being counted but how and why it was done. Metadata Modern population ... their country s census results and other population statistics on their agency s website. See also Census Census Bureau , Census tract , Census block group , Census block . Intercensal estimate Population ... Population country lists Category Demography Category Population ... more details
Orphan date February 2009 In neuroscience , a population vector is the sum of the preferred directions of a population of neuron s, weighted by the respective spike counts. The formula for computing the normalized population vector, math F math , takes the following form math F frac sum j m j F j sum j m j math Where math m j math is the activity of cell math j math , and math F j math is the preferred input for cell math j math . Note that the vector math F math encodes the input direction, math F j math , in terms of the activation of a population of neurons. biology stub Category Neuroscience ... more details
Law of Population 1830 was a massive treatise written by Michael Thomas Sadler as a response to Thomas Robert Malthus s works on population growth, notably An Essay on the Principle of Population first edition 1798 . In his essay, Sadler refutes Malthus conclusions regarding the geometric growth of populations and proposes that the growth of populations is a far less worrisome menace. At this period population growth had become a political bugbear throughout England, Citation needed date February 2010 much in a way comparable to modern day fears of terrorism or Cold War fears of nuclear war . In this work Sadler proposed many factors in models of population growth that are now widely accepted as fact, Citation needed date February 2010 such as that Birth rates tend to decline with increasing levels of prosperity. Citation needed date February 2010 See also http books.google.com books?id 3CZBAAAAIAAJ&printsec frontcover&dq law of population sadler&source bl&ots os UfHFXCt&sig l4V7kPo fLdAwQHQNlRfZOithE4&hl en&ei qxqS ftAYaUnQeTzrj8BQ&sa X&oi book result&ct result&resnum 1&ved 0CAkQ6AEwAA v onepage&q &f false The Law of Population , Vol. 1 Category 1830 books Category Essays Category Social sciences books Category Economics books ... more details
Unreferenced date March 2008 In applied probability , a population process is a Markov chain in which the state of the chain is analogous to the number of individuals in a population 0, 1, 2, etc. , and changes to the state are analogous to the addition or removal of individuals from the population. Although named by analogy to biology biological populations, population processes find application in a much wider range of fields than just ecology and other biological sciences. These other applications include telecommunication s and queueing theory , chemical kinetics and financial mathematics , and hence the population could be of packet switching packet s in a computer network , of molecule s in a chemical reaction , or even of units in a stock market index financial index . Population processes are typically characterized by processes of birth and immigration, and of death, emigration and catastrophe, which correspond to the basic demography demographic processes and broad natural environment environment al effects to which a population is subject. However, population processes are also often equivalent to other processes that may typically be characterised under other paradigm s in the literal sense of patterns . queueing theory Queues , for example, are often characterised by an arrivals process, a service process, and the number of servers. In appropriate circumstances, however, arrivals at a queue are functionally equivalent to births or immigration and the service of waiting customers is equivalent to death or emigration. Typical population processes include birth death process es and birth, death and catastrophe process es. See also div style moz column count 4 column count 4 Moran Process div Category Demography Category Population Category Markov models ... more details
A disjunctive population , in ecology , is a colony of plants or animals, whose geographical locus is severed from the continuous range of the bulk of the species distribution. Although a disjunctive population may sometimes occur on an island, ref A.W.D. Larkum, Robert Joseph Orth and Carlos M. Duarte. 2006 ref which creates physical separation via water, a large percentage of disjunctive populations are separated from their main range simply by landmass. In some cases a disjunctive population represents a relatively small outlier population from the main range, but in other cases, such as for the Painted Hunting Dog , Lycaon pictus , the entire population is scattered throughout much of Africa and is intrinsically disjunctive. See also Ecological island Disjunct distribution References A.W.D. Larkum, Robert Joseph Orth and Carlos M. Duarte. 2006. Seagrasses biology, ecology, and conservation , Published by Springer, ISBN 140202942X, 9781402029424 691 pages Line notes reflist Category Ecology biology stub ... more details
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