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Steven M. Stanley (born November 2, 1941) is an American paleontologist and evolutionary biologist at the Florida State University. He is best known for his empirical research documenting the evolutionary process of punctuated equilibrium in the fossil record.
Stanley received his Ph.D. from Yale University in 1968. For most of his career he taught geology at Johns Hopkins University (1969-2005). In 1977 Stanley was awarded the Paleontological Society's Charles Schuchert Award which is presented "to a person under 40 whose work reflects excellence and promise in the science of paleontology." [1] In 2007 he was awarded the Society's Paleontological Society Medal, which is "awarded to a person whose eminence is based on advancement of knowledge in paleontology." [1] In 2006 Stanley was awarded the Mary Clark Thompson Medal by the National Academy of Sciences [2] and in 2008 the William H. Twenhofel Medal by the Society for Sedimentary Geology. [3]
In 1972 Stanley developed the Predation Hypothesis to explain the evolution of novelties in the Cambrian explosion. Stanley proposed that predation stimulated prey animals to evolve defenses such as shells, rapid swimming, and burrowing. These strategies also opened new avenues of evolution through functional shifts. Hard shells allowed for filter feeding, and deep burrowing allowed animals to gain new access to food resources. [4]
Stanley acted as a “personal editor” on several PNAS papers about the controversial Younger Dryas impact hypothesis, starting with the original 2007 paper and continuing even after revelations of misconduct by a key contributor. [5] He admitted to a Nature reporter that “It has been very controversial… It’s my view that I should help to get this stuff published.” [6] The hypothesis was comprehensively refuted in 2023. [7]
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The timeline of the evolutionary history of life represents the current scientific theory outlining the major events during the development of life on planet Earth. Dates in this article are consensus estimates based on scientific evidence, mainly fossils.
Gradualism, from the Latin gradus ("step"), is a hypothesis, a theory or a tenet assuming that change comes about gradually or that variation is gradual in nature and happens over time as opposed to in large steps. Uniformitarianism, incrementalism, and reformism are similar concepts. For the Social democratics, the socialist society is achieved through gradualism.
In evolutionary biology, punctuated equilibrium is a theory that proposes that once a species appears in the fossil record, the population will become stable, showing little evolutionary change for most of its geological history. This state of little or no morphological change is called stasis. When significant evolutionary change occurs, the theory proposes that it is generally restricted to rare and geologically rapid events of branching speciation called cladogenesis. Cladogenesis is the process by which a species splits into two distinct species, rather than one species gradually transforming into another.
Clovis culture is a prehistoric Paleoamerican archaeological culture, named for distinct stone and bone tools found in close association with Pleistocene fauna, particularly two Columbian mammoths, at Blackwater Locality No. 1 near Clovis, New Mexico, in 1936 and 1937, though Paleoindian artifacts had been found at the site since the 1920s. It existed from roughly 11,500 to 10,800 BCE near the end of the Last Glacial Period.
Reginald Aldworth Daly was a Canadian geologist. He is best known for being one of the first proponents of the giant-impact hypothesis of the formation of the Moon.
The pygmy mammoth or Channel Islands mammoth is an extinct species of dwarf elephant native to the northern Channel Islands off the coast of California. It was descended from the Columbian mammoth of mainland North America.
David M. Raup was a University of Chicago paleontologist. Raup studied the fossil record and the diversity of life on Earth. Raup contributed to the knowledge of extinction events along with his colleague Jack Sepkoski. They suggested that the extinction of dinosaurs 66 mya was part of a cycle of mass extinctions that may have occurred every 26 million years.
The history of genetics dates from the classical era with contributions by Pythagoras, Hippocrates, Aristotle, Epicurus, and others. Modern genetics began with the work of the Augustinian friar Gregor Johann Mendel. His works on pea plants, published in 1866, provided the initial evidence that, on its rediscovery in 1900's, helped to establish the theory of Mendelian inheritance.
In biology, saltation is a sudden and large mutational change from one generation to the next, potentially causing single-step speciation. This was historically offered as an alternative to Darwinism. Some forms of mutationism were effectively saltationist, implying large discontinuous jumps.
Paleobiology is an interdisciplinary field that combines the methods and findings found in both the earth sciences and the life sciences. Paleobiology is not to be confused with geobiology, which focuses more on the interactions between the biosphere and the physical Earth.
H. Allen Orr is the Shirley Cox Kearns Professor of Biology at the University of Rochester.
The history of life on Earth traces the processes by which living and fossil organisms evolved, from the earliest emergence of life to present day. Earth formed about 4.5 billion years ago and evidence suggests that life emerged prior to 3.7 Ga. Although there is some evidence of life as early as 4.1 to 4.28 Ga, it remains controversial due to the possible non-biological formation of the purported fossils.
Derrick Norman Lehmer was an American mathematician and number theorist.
William Martin is an American botanist and microbiologist, currently Head of the Institut für Molekulare Evolution, Heinrich Heine Universität, Düsseldorf.
Hybrid inviability is a post-zygotic barrier, which reduces a hybrid's capacity to mature into a healthy, fit adult. The relatively low health of these hybrids relative to pure-breed individuals prevents gene flow between species. Thus, hybrid inviability acts as an isolating mechanism, limiting hybridization and allowing for the differentiation of species.
Mary Jane West-Eberhard is an American theoretical biologist noted for arguing that phenotypic and developmental plasticity played a key role in shaping animal evolution and speciation. She is also an entomologist notable for her work on the behavior and evolution of social wasps.
Adrian Lewis Melott is an American physicist. He is one of the pioneers of using large-scale computing to investigate the formation of large-scale structure in a Universe dominated by dark matter. He later turned his attention to an area he calls “astrobiophysics”, examining a variety of ways that external events in our galaxy may have influenced the course of life on Earth, including analysis of gamma-ray burst events.
The court jester hypothesis is used in reference to the idea that abiotic forces, rather than biotic competition between species, function as a major driving force behind the processes in evolution which produce speciation. In evolutionary theory, the court-jester hypothesis contrasts the Red Queen hypothesis.
Jürgen Brosius is a German molecular geneticist and evolutionary biologist. He was professor and director of the Institute of Experimental Pathology at the University of Münster. Some of his scientific contributions involve the first genetic sequencing of a ribosomal RNA operon, the design of plasmids for studying gene expression, expression vectors for high-level production of recombinant proteins and RNA, RNA biology, RNomics as well as the significance of retroposition for plasticity and evolution of genomes, genes and gene modules including regulatory sequences or elements.
Charles Richard Marshall is an Australian paleobiologist and the director of the University of California Museum of Paleontology, where he is also a professor in the department of Integrative Biology at the University of California, Berkeley.
