Search results
Results from the WOW.Com Content Network
The Structure of Evolutionary Theory (2002) is Harvard paleontologist Stephen Jay Gould's technical book on macroevolution and the historical development of evolutionary theory. [1] The book was twenty years in the making, [2] published just two months before Gould's death. [3] Aimed primarily at professionals, [4] the volume is divided into ...
The evolutionary biologists Kenneth McNamara and Michael McKinney stated in 2005 that of all the books that Gould wrote in his career, "the one with the most impact is probably Ontogeny and Phylogeny... to say that this work is a hallmark in this area of evolutionary theory would be an understatement.
The theory proposes that most evolution is characterized by long periods of evolutionary stability, infrequently punctuated by swift periods of branching speciation. The theory was contrasted against phyletic gradualism , the popular idea that evolutionary change is marked by a pattern of smooth and continuous change in the fossil record.
The modern evolutionary synthesis is the outcome of a merger of several different scientific fields to produce a more cohesive understanding of evolutionary theory. In the 1920s, Ronald Fisher , J.B.S. Haldane and Sewall Wright combined Darwin's theory of natural selection with statistical models of Mendelian genetics , founding the discipline ...
The complexity distribution is bounded at one side (a living organism cannot be much simpler than bacteria), so an unbiased random walk by evolution, sometimes going in the complexity direction and sometimes going towards simplicity (without having an intrinsic preference to either), will create a distribution with a small, but longer and ...
In Darwin's theory of natural selection, more organisms are produced than can survive. Some have variations that give them a competitive advantage, and they have the best chance of surviving and procreating. The main element lacking in the theory was any mechanism that would allow organisms to pass on these favorable variations.
In the so-called modern synthesis of the early 20th century, between 1918 and 1930 Ronald Fisher brought together Darwin's theory of evolution, with its insistence on natural selection, heredity, and variation, and Gregor Mendel's laws of genetics into a coherent structure for evolutionary biology. Biologists assumed that an organism was a ...
Professor of biology Jerry Coyne sums up biological evolution succinctly: [3]. Life on Earth evolved gradually beginning with one primitive species – perhaps a self-replicating molecule – that lived more than 3.5 billion years ago; it then branched out over time, throwing off many new and diverse species; and the mechanism for most (but not all) of evolutionary change is natural selection.