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Eldredge and Gould, proposing that evolution jumps between stability and relative rapidity, are described as "discrete variable speedists", and "in this respect they are genuinely radical." [67] They assert that evolution generally proceeds in bursts, or not at all. "Continuously variable speedists", on the other hand, advance that ...
Three examples of Turing patterns Six stable states from Turing equations, the last one forms Turing patterns. The Turing pattern is a concept introduced by English mathematician Alan Turing in a 1952 paper titled "The Chemical Basis of Morphogenesis" which describes how patterns in nature, such as stripes and spots, can arise naturally and autonomously from a homogeneous, uniform state.
In biology, evolution is the process of change in all forms of life over generations, and evolutionary biology is the study of how evolution occurs. Biological populations evolve through genetic changes that correspond to changes in the organisms ' observable traits .
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.
Punctuated equilibrium is a refinement to evolutionary theory. It describes patterns of descent taking place in "fits and starts" separated by long periods of stability. Eldredge went on to develop a hierarchical vision of evolutionary and ecological systems. Around this time, he became focused on the rapid destruction of many of the world's ...
By the return journey, he was connecting patterns of geographical and historical distribution, and starting to doubt the stability of Species. In September 1838 he conceived his theory of natural selection as the cause of evolution , then as well as developing his career as a geologist and writer worked privately on finding evidence and ...
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.
The Russian evolutionary biologist Ivan Schmalhausen founded the theory of stabilizing selection, publishing a paper in Russian titled "Stabilizing selection and its place among factors of evolution" in 1941 and a monograph "Factors of Evolution: The Theory of Stabilizing Selection" in 1945. [5] [6]