Demic diffusion, as opposed to
trans-cultural diffusion
In cultural anthropology and cultural geography, cultural diffusion, as conceptualized by Leo Frobenius in his 1897/98 publication ''Der westafrikanische Kulturkreis'', is the spread of cultural items—such as ideas, styles, religions, technologi ...
, is a
demographic
Demography () is the statistical study of populations, especially human beings.
Demographic analysis examines and measures the dimensions and dynamics of populations; it can cover whole societies or groups defined by criteria such as edu ...
term referring to a migratory model, developed by
Luigi Luca Cavalli-Sforza
Luigi Luca Cavalli-Sforza (; 25 January 1922 – 31 August 2018) was an Italian geneticist. He was a population geneticist who taught at the University of Parma, the University of Pavia and then at Stanford University.
Works
Schooling and po ...
, of population
diffusion
Diffusion is the net movement of anything (for example, atoms, ions, molecules, energy) generally from a region of higher concentration to a region of lower concentration. Diffusion is driven by a gradient in Gibbs free energy or chemical p ...
into and across an area that had been previously uninhabited by that group and possibly but not necessarily displacing, replacing, or intermixing with an existing
population
Population typically refers to the number of people in a single area, whether it be a city or town, region, country, continent, or the world. Governments typically quantify the size of the resident population within their jurisdiction using a ...
(such as has been suggested for the spread of
agriculture
Agriculture or farming is the practice of cultivating plants and livestock. Agriculture was the key development in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that enabled people to ...
across
Neolithic
The Neolithic period, or New Stone Age, is an Old World archaeological period and the final division of the Stone Age. It saw the Neolithic Revolution, a wide-ranging set of developments that appear to have arisen independently in several parts ...
Europe
Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a Continent#Subcontinents, subcontinent of Eurasia ...
and several other
''Landnahme'' events).
In its original formulation, the demic diffusion model includes three phases: (1) population growth, prompted by new available resources as in the case of early farmers, and/or other technological developments; (2) a dispersal into regions with lower population density; (3) a limited initial admixture with the people encountered in the process.
Evidence
Theoretical work by Cavalli-Sforza showed that if admixture between expanding farmers and previously-resident groups of hunters and gatherers was not immediate, the process would result in the establishment of broad genetic gradients. Because broad gradients, spanning much of Europe from southeast to northwest, were identified in empirical genetic studies by Cavalli-Sforza,
Robert R. Sokal
Robert Reuven Sokal (January 13, 1926 in Vienna, Austria – April 9, 2012 in Stony Brook, New York) was an Austrian-American biostatistician and entomologist. Distinguished Professor Emeritus at the Stony Brook University, Sokal was a member ...
,
Guido Barbujani
Guido Barbujani (born January 31, 1955) is an Italian population geneticist, evolutionary biologist and literary author born in Adria, who has worked with the State University of New York at Stony Brook (NY), University of Padua, and University o ...
,
Lounès Chikhi Dr Lounès Chikhi (born Paris, France) is a French population geneticist of Algerian Berber extraction, based at the Université Paul Sabatier in Toulouse, France, and also at the Instituto Gulbenkian de Ciência in Oeiras, Portugal, where he runs ...
and others, it seemed likely that the spread of agriculture into Europe occurred by the expansion and the spread of agriculturists, who possibly originated in the
Fertile Crescent
The Fertile Crescent ( ar, الهلال الخصيب) is a crescent-shaped region in the Middle East, spanning modern-day Iraq, Syria, Lebanon, Israel, Palestine and Jordan, together with the northern region of Kuwait, southeastern region of ...
of the
Near East
The ''Near East''; he, המזרח הקרוב; arc, ܕܢܚܐ ܩܪܒ; fa, خاور نزدیک, Xāvar-e nazdik; tr, Yakın Doğu is a geographical term which roughly encompasses a transcontinental region in Western Asia, that was once the hist ...
. That is referred to as the Neolithic demic diffusion model.
Craniometric
Craniometry is measurement of the cranium (the main part of the skull), usually the human cranium. It is a subset of cephalometry, measurement of the head, which in humans is a subset of anthropometry, measurement of the human body. It is disti ...
and
archaeological
Archaeology or archeology is the scientific study of human activity through the recovery and analysis of material culture. The archaeological record consists of artifacts, architecture, biofacts or ecofacts, sites, and cultural landscap ...
[M. Zvelebil, ''Antiquity 63'' (1989) pp. 379–383.] studies have also arrived at the same conclusion.
References
{{Reflist
External links
Estimating the Impact of Prehistoric Admixture on the Genome of Europeans, Dupanloup et al., 2004Origin, Diffusion, and Differentiation of Y-Chromosome Haplogroups E and J: Inferences on the Neolithization of Europe and Later Migratory Events in the Mediterranean Area, 2004Y genetic data support the Neolithic demic diffusion model, Chikhi 2002.
Paleolithic and Neolithic lineages in the European mitochondrial gene pool, Cavalli-Sforza 1997.Clines of nuclear DNA markers suggest a largely Neolithic ancestry of the European gene, Chikhi 1997.
Demographics