Adaptation Aspect of an organism that was created by the process of natural selection because it served an adaptive function Adaptive Contributing to the eventual reproduction of an organism or its relatives Bayes's theorem Specifies the probability that a hypothesis is true, given new data; P(HJD) = P(H)P(DIH)/P(D), where H is the hypothesis and D is the new data Cognitive psychology Study of ...

R.A. Fisher, in his 1929 book The Genetical Theory of Natural Selection, noted that Charles Darwin believed in the theory of blending inheritance, and that this conditioned his views on variation and therefore on theories for the possible causes of evolution. Darwin realized that blending, or fusion, inheritance reduces variation and that all variability must be continually at work, or else nat...

New ideas in human behavior genetics may be set in motion by construing psychological groups as Mendelian populations (Tryon, 1957; Thompson, 1957). The continuity, complexity, and fluidity of behavior (Thompson, 1964) together with the hazards of interpretation of phenotypic correlations impose barriers on those who do 'research in this area which may impair their vision of solutions to the pa...

The first published expression of the theory of evolution by natural selection was printed July 1, 1858, in the Journal of the Linnaean Society of London in the form of two essays: one by Charles Darwin and one by Alfred Russel Wallace. These two essays, along with Darwin's preliminary Sketch of 1842 and his Essay of 1844 (neither of which were published until 1909), and a foreword by Sir Gavin...

More than any other species, humans form social ties to individuals who are neither kin nor mates, and these ties tend to be with similar people. Here, we show that this similarity extends to genotypes. Across the whole genome, friends' genotypes at the single nucleotide polymorphism level tend to be positively correlated (homophilic). In fact, the increase in similarity relative to strangers i...

How can a system become better adapted over time without natural selection? Although some argue for ‘organismic’ properties such as robustness and self-sustaining regulation in non-evolved systems [1,5,11], others insist that natural selection is the only source of true adaptation [3]. We suggest that understanding how adaptation can occur without natural selection remains a fundamental open qu...

Joseph Hooker became one of the most influential botanists of his day. He is best remembered as a friend of Charles Darwin and an early advocate of natural selection. However, after returning to Britain from his first major voyage, Hooker spent years struggling to find a paid position that would allow him to pursue his studies of plant classification and distribution. As he worked to establish ...