Found 508 Documents across 51 Pages (0.01 seconds)
  1. Population migration and the variation of dopamine D4 receptor (DRD4) allele frequencies around the globeChen, Chuansheng - Evolution and Human Behavior, 1999 - 4 Hypotheses

    Dopamine receptor D4 (DRD4) exhibits the largest number of polymorphisms of any dopamine receptor yet identified, and variation in DRD4 has been linked to variation in traits such as novelty-seeking and attention deficit/hyperactivity disorder. DRD4 also exhibits large variation between populations. Here, the authors test the hypothesis that natural selection acting on DRD4 may account for variation in between-population migratory patterns, using genetic and historical data from 39 populations.

    Related DocumentsCite
  2. Correlations in the population structure of music, genes and languageBrown, Steven - Proc. R. Soc. B, 2014 - 6 Hypotheses

    By testing relationships between musical, geographic, genetic, and linguistic distance among nine indigenous groups in Taiwan, the researchers aim to quantitatively evaluate a developing theory of coevolution between these traits. An especially strong correlation between musical variability and genetic distance suggests that music may possess worldwide time depth, diversity, and universality equal to or greater than that of language, and could thus serve as a complementary marker for reconstruction of long-term population shifts.

    Related DocumentsCite
  3. Semes and genes in africaHewlett, Barry S. - Current Anthropology, 2002 - 4 Hypotheses

    Genetic, linguistic, and geographic data can be used to explain the distribution of cultural units ("semes") and to understand the evolutionary mechanisms of culture. Three broad models of cultural transmission attempt to explain why cultures share semes: (1) Cultural diffusion, emphasizing horizontal transmission. (2) Local adaptation, where trail-and-error learning leads to the independent adoption of semes by different peoples living in similar environments. (3) Demic diffusion, which emphasizes vertical and frequency-dependent transmission. Authors test the explanatory power of each model using cultural, genetic, linguistic and geographic data from 36 African cultures.

    Related DocumentsCite
  4. Human variation in the shape of the birth canal is significant and geographically structuredBetti, Lia - Proceedings of the Royal Society B, 2018 - 5 Hypotheses

    The 'obstetrical dilemma' postulates that human females evolved a pelvis shape that was a compromise between the needs of bipedal locomotion and the need for a wider pelvic opening. The implication is that the female pelvis should be similar across the world. Researchers examine the size and shape of the birth canal of female individuals in the Goldman and Human Origin datasets. Contrary to the 'obstetrical dilemma,' the findings reveal that there is indeed significant geographical variation in size and shape of the female birth canal. Neutral evolutionary processes, particularly genetic drift, were suggested to be influential in female canal shape whereas the predicted effects of climate on canal diversity were only minimal.

    Related DocumentsCite
  5. Phylogeographic analysis of the Bantu language expansion supports a rainforest routeKoile, Ezequiel - Proceedings of the National Academy of Sciences, 2022 - 4 Hypotheses

    How and when did Bantu populations expand through sub-Saharan Africa? Using phylogeographic analyses, the authors test four main hypotheses which aim to explain the route that the Bantu took as well as the date of expansion. The results suggest that Bantu populations migrated through the Central African rainforest around 4,400 years ago.

    Related DocumentsCite
  6. Phylogenetic analysis of the evolution of lactose digestion in adultsHolden, Clare - Human Biology, 1997 - 4 Hypotheses

    The ability of adults to digest lactose is common only in populations of European and circum-Mediterranean origin, a distribution thought to be a result of genetic adaptation to drinking milk from domestic livestock. Two additional hypotheses have been proposed to explain the distribution of high lactose digestion capacity: (1) supplemental calcium in high-latitude populations prone to vitamin D deficiency and (2) maintenance of water and electrolytes in the body in highly arid environments. However, these hypotheses are confounded by the shared ancestry of populations whose lactose digestion capability has been tested. Therefore, the authors test all three hypotheses using a phylogenetic comparative method for 62 cultures.

    Related DocumentsCite
  7. Combination of Genetic and Humanitarian (Cross-Cultural) Methods for the Identification of Human Genes Involved in the Process of Adaptation to Evolutionary New Environmental FactorsBorinskaya, S. A. - Russian Journal of Genetics, 2015 - 7 Hypotheses

    Researchers used population samples from the ALFRED database and the Human Genome Diversity Project (HGDP), in conjunction with 68 populations from the Ethnographic Atlas, in an attempt to identify specific genes involved in human adaptation to environmental stimuli as a result of migration. Specifically, researchers looked at the allele frequencies for four different genes typically associated with varying subsistence forms. These four included the APOE apolipoprotein E gene (lipid transport and regulation of cholesterol), LCT lactase gene (enzyme that decomposes lactose), CCR5 chemokine receptor gene (deletion mutation that decreases immunodeficiency virus propagation), and the ADH1B alcohol dehydrogenase gene (important enzyme for alcohol metabolism). The allele frequencies were then analyzed to distinguish any possible correlation to economic-culture types using a two-sided Spearman Test. Researchers also ran a similar test to analyze allele frequencies and pathogen load, however the majority of the findings were not statistically significant. The findings suggest that there is a definite relationship between the allele frequencies and type of economy of a population.

    Related DocumentsCite
  8. The evolution of ethnolinguistic diversityCurrie, Thomas E. - Advances in Complex Systems, 2012 - 2 Hypotheses

    The authors test the relationship between ethnolinguistic area and various environmental variables in a cross-cultural sample of hunter-gatherer, pastoral, and agricultural subsistence groups in order to evaluate various hypotheses surrounding the geographic and ecological origins of cultural diversity. They propose that societies which adopted agriculture at the beginning of the Holocene were less directly affected by climate which, combined with the effect of increasing political and cultural complexity, allowed coordination and homogenization of ethnolinguistic groups over a broader swathe of territory.

    Related DocumentsCite
  9. Exploring correlations in genetic and cultural variation across language families in northeast AsiaMatsumae, Hiromi - Science Advances, 2021 - 7 Hypotheses

    This article explores the possible relationship between the cultural evolution of language, music, and genetic variation beyond the level of language families. Due to their linguistic diversity, the authors use a sample of 14 Northeast Asian societies with matching information on their music, genetics, and linguistic patterns. The variables measuring language are lexicon, phonology, and grammar. Then, the authors compare each variable's relationship to music and genetic variation. The results only show a significant correlation between grammar and genetic variation.

    Related DocumentsCite
  10. Spread of cattle led to the loss of matrilineal descent in Africa: a coevolutionary analysisHolden, Clare Janki - Proceedings of the Royal Society of London B: Biological Sciences, 2003 - 2 Hypotheses

    Through phylogenetic comparison, Holden and Mace explore the relationship between descent and cattle among a sample of 68 Bantu/Bantoid-speaking populations in Africa. The authors posit that when matrilineal cultures adopt cattle, they become patrilineal. Possible theories are offered to explain trends and variation in the data.

    Related DocumentsCite