Demographic historyDemographic history is the reconstructed record of human population in the past. Given the lack of population records prior to the 1950s, there are many gaps in our record of demographic history. Historical demographers must make do with estimates, models and extrapolations. For the demographic methodology, see historical demography. World population estimates Estimating the ancestral population of anatomically modern humans, Colin McEvedy and Richard Jones chose bounds based on gorilla and chimpanzee population densities of 1/km2 and 3-4/km2, respectively, then assumed that as Homo erectus moved up the food chain, they lost an order of magnitude in density.
Molecular Phylogenetics and EvolutionMolecular Phylogenetics and Evolution is a peer-reviewed scientific journal of evolutionary biology and phylogenetics. The journal is edited by E.A. Zimmer.
Nearly neutral theory of molecular evolutionThe nearly neutral theory of molecular evolution is a modification of the neutral theory of molecular evolution that accounts for the fact that not all mutations are either so deleterious such that they can be ignored, or else neutral. Slightly deleterious mutations are reliably purged only when their selection coefficient are greater than one divided by the effective population size. In larger populations, a higher proportion of mutations exceed this threshold for which genetic drift cannot overpower selection, leading to fewer fixation events and so slower molecular evolution.
Ring speciesIn biology, a ring species is a connected series of neighbouring populations, each of which interbreeds with closely sited related populations, but for which there exist at least two "end populations" in the series, which are too distantly related to interbreed, though there is a potential gene flow between each "linked" population and the next. Such non-breeding, though genetically connected, "end populations" may co-exist in the same region (sympatry) thus closing a "ring".
Evolution of biological complexityThe evolution of biological complexity is one important outcome of the process of evolution. Evolution has produced some remarkably complex organisms – although the actual level of complexity is very hard to define or measure accurately in biology, with properties such as gene content, the number of cell types or morphology all proposed as possible metrics. Many biologists used to believe that evolution was progressive (orthogenesis) and had a direction that led towards so-called "higher organisms", despite a lack of evidence for this viewpoint.
Estimates of historical world populationThis article lists current estimates of the world population in history. In summary, estimates for the progression of world population since the Late Middle Ages are in the following ranges: Estimates for pre-modern times are necessarily fraught with great uncertainties, and few of the published estimates have confidence intervals; in the absence of a straightforward means to assess the error of such estimates, a rough idea of expert consensus can be gained by comparing the values given in independent publications.
Dual inheritance theoryDual inheritance theory (DIT), also known as gene–culture coevolution or biocultural evolution, was developed in the 1960s through early 1980s to explain how human behavior is a product of two different and interacting evolutionary processes: genetic evolution and cultural evolution. Genes and culture continually interact in a feedback loop, changes in genes can lead to changes in culture which can then influence genetic selection, and vice versa.
Universal DarwinismUniversal Darwinism, also known as generalized Darwinism, universal selection theory, or Darwinian metaphysics, is a variety of approaches that extend the theory of Darwinism beyond its original domain of biological evolution on Earth. Universal Darwinism aims to formulate a generalized version of the mechanisms of variation, selection and heredity proposed by Charles Darwin, so that they can apply to explain evolution in a wide variety of other domains, including psychology, linguistics, economics, culture, medicine, computer science, and physics.
Teleology in biologyTeleology in biology is the use of the language of goal-directedness in accounts of evolutionary adaptation, which some biologists and philosophers of science find problematic. The term teleonomy has also been proposed. Before Darwin, organisms were seen as existing because God had designed and created them; their features such as eyes were taken by natural theology to have been made to enable them to carry out their functions, such as seeing.
Inclusive fitnessIn evolutionary biology, inclusive fitness is one of two metrics of evolutionary success as defined by W. D. Hamilton in 1964: Personal fitness is the number of offspring that an individual begets (regardless of who rescues/rears/supports them) Inclusive fitness is the number of offspring equivalents that an individual rears, rescues or otherwise supports through its behaviour (regardless of who begets them) An individual's own child, who carries one half of the individual's genes, is defined as one offspring equivalent.