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Leslie D. Gottlieb
Leslie David Gottlieb (1936–2012) was a United States biologist described by the Botanical Society of America as "one of the most influential plant evolutionary biologists over the past several decades". He was employed at the University of California, Davis for 34 years, and published widely. In addition to his primary work in plant genetics, Gottlieb was an advocate for rare and endangered plant conservation. Education Following a Bachelor of Arts degree in English from Cornell University in 1957, Gottlieb's career began at Oregon State University in the Botany and Plant Pathology Department. He earned a master's degree in December 1965 with major professor Dr. Kenton Chambers and wrote a thesis on hybridization between species of manzanita (''Arctostaphylos'') trees in southwestern Oregon. His PhD at the University of Michigan 1969 examined patterns of diversity and mechanisms of speciation in '' Stephanomeria''. He was a faculty member of the Department of Genetics at the U ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Royal Botanic Gardens, Kew
Royal Botanic Gardens, Kew is a non-departmental public body in the United Kingdom sponsored by the Department for Environment, Food and Rural Affairs. An internationally important botanical research and education institution, it employs 1,100 staff. Its board of trustees is chaired by Dame Amelia Fawcett. The organisation manages botanic gardens at Kew in Richmond upon Thames in south-west London, and at Wakehurst, a National Trust property in Sussex which is home to the internationally important Millennium Seed Bank, whose scientists work with partner organisations in more than 95 countries. Kew, jointly with the Forestry Commission, founded Bedgebury National Pinetum in Kent in 1923, specialising in growing conifers. In 1994, the Castle Howard Arboretum Trust, which runs the Yorkshire Arboretum, was formed as a partnership between Kew and the Castle Howard Estate. In 2019, the organisation had 2,316,699 public visitors at Kew, and 312,813 at Wakehurst. Its site at Kew ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manzanita
Manzanita is a common name for many species of the genus ''Arctostaphylos''. They are evergreen shrubs or small trees present in the chaparral biome of western North America, where they occur from Southern British Columbia and Washington to Oregon, California, Utah, Arizona, New Mexico, and Texas in the United States, and throughout Mexico. Manzanitas can live in places with poor soil and little water. They are characterized by smooth orange or red bark and stiff, twisting branches. There are 105 species and subspecies of manzanita, 95 of which are found in the Mediterranean climate and colder mountainous regions of California, ranging from ground-hugging coastal and mountain species to small trees up to 20 feet (6m) tall. Manzanitas bloom in the winter to early spring and carry berries in spring and summer. The berries and flowers of most species are edible. The word ''manzanita'' is the Spanish diminutive of ''manzana'' (apple). A literal translation would be ''little apple' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clarkia Rubicunda
''Clarkia rubicunda'' is a flowering plant endemic to California. It is found mostly on the Central Coast part of the state. The plant is known by the common names ''Ruby Chalice Clarkia'' and ''Farewell to Spring''. ''Clarkia rubicunda'' bears attractive poppy-like blooms with wide, cup-shaped corollas of four pink or purplish petals. The corolla of the flower sometimes has a bright red center. As the common name suggests, it blooms in June and July. It is similar in appearance to another flower of genus ''Clarkia'', the ''Clarkia amoena'', also called "Farewell to Spring". References Further reading *Bartholomew, B., L. C. Eaton, and P. H. Raven. (1973). ''Clarkia rubicunda'': A Model of Plant Evolution in Semiarid Regions. ''Evolution Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction. Var ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stephanomeria Malheurensis
''Stephanomeria malheurensis'', the Malheur wirelettuce, is a species of flowering plant in the family Asteraceae. It is endemic to Oregon in the United States. It is a federally listed endangered species. It was discovered in 1966 and the population at the type locality in Harney County is the only one ever known. For several years in the 1980s it disappeared. Scattered individuals have been noted over the years. Plants were grown from seed at the Berry Botanic Garden in Portland and planted at the original site. Some still survived as of 2001.''Stephanomeria malheurensis''. Center for Plant Conservation. This species grows atop hills surrounded by flat land. The soils are derived from |
Ploidy
Ploidy () is the number of complete sets of chromosomes in a cell (biology), cell, and hence the number of possible alleles for Autosome, autosomal and Pseudoautosomal region, pseudoautosomal genes. Sets of chromosomes refer to the number of maternal and paternal chromosome copies, respectively, in each homologous chromosome pair, which chromosomes naturally exist as. Somatic cells, Tissue (biology), tissues, and Individual#Biology, individual organisms can be described according to the number of sets of chromosomes present (the "ploidy level"): monoploid (1 set), diploid (2 sets), triploid (3 sets), tetraploid (4 sets), pentaploid (5 sets), hexaploid (6 sets), heptaploid or septaploid (7 sets), etc. The generic term polyploidy, polyploid is often used to describe cells with three or more chromosome sets. Virtually all sexual reproduction, sexually reproducing organisms are made up of somatic cells that are diploid or greater, but ploidy level may vary widely between different or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Disruptive Selection
Disruptive selection, also called diversifying selection, describes changes in population genetics in which extreme values for a trait are favored over intermediate values. In this case, the variance of the trait increases and the population is divided into two distinct groups. In this more individuals acquire peripheral character value at both ends of the distribution curve. Overview Natural selection is known to be one of the most important biological processes behind evolution. There are many variations of traits, and some cause greater or lesser reproductive success of the individual. The effect of selection is to promote certain alleles, traits, and individuals that have a higher chance to survive and reproduce in their specific environment. Since the environment has a carrying capacity, nature acts on this mode of selection on individuals to let only the most fit offspring survive and reproduce to their full potential. The more advantageous the trait is the more com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sympatric Speciation
Sympatric speciation is the evolution of a new species from a surviving ancestral species while both continue to inhabit the same geographic region. In evolutionary biology and biogeography, sympatric and sympatry are terms referring to organisms whose ranges overlap so that they occur together at least in some places. If these organisms are closely related (e.g. sister species), such a distribution may be the result of sympatric speciation. Etymologically, sympatry is derived from the Greek roots ("together") and ("homeland"). The term was coined by Edward Bagnall Poulton in 1904, who explains the derivation. Sympatric speciation is one of three traditional geographic modes of speciation.Futuyma, D. J. 2009. ''Evolution'' (2nd edition). Sinauer Associates, Inc. Allopatric speciation is the evolution of species caused by the geographic isolation of two or more populations of a species. In this case, divergence is facilitated by the absence of gene flow. Parapatric speciation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Verne Grant
Verne Edwin Grant (1917-2007) was an American botanist and writer. Grant was born in San Francisco, California. In 1940 he received his BA in Botany and in 1949 his PhD in Botany and Genetics from the University of California, Berkeley. He was the Professor of Botany for the University of Texas at Austin from 1970 to 1987. His book ''The Origins of Adaptations'' (1963) discussed the main themes of the modern synthesis such as genetic drift, modes of speciation, natural selection and population genetics. However, Grant did not describe these mechanisms of evolution as "Neo-Darwinism" or the synthetic theory, instead he referred to these mechanisms as the "causal theory." The book was awarded the 1964 Phi Beta Kappa Award in Science. Systematic botanist Áskell Löve in a review for the book wrote that "Grant has succeeded in writing a text that is likely to affect the thinking in this field for decades to come and also to be regarded by students as one of the most informative tex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quantum Speciation
Peripatric speciation is a mode of speciation in which a new species is formed from an isolated peripheral population. Since peripatric speciation resembles allopatric speciation, in that populations are isolated and prevented from exchanging genes, it can often be difficult to distinguish between them. Nevertheless, the primary characteristic of peripatric speciation proposes that one of the populations is much smaller than the other. The terms peripatric and peripatry are often used in biogeography, referring to organisms whose ranges are closely adjacent but do not overlap, being separated where these organisms do not occur—for example on an oceanic island compared to the mainland. Such organisms are usually closely related (''e.g.'' sister species); their distribution being the result of peripatric speciation. The concept of peripatric speciation was first outlined by the evolutionary biologist Ernst Mayr in 1954.Ernst Mayr. (1954). Change of genetic environment and evolu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leslie D
Leslie may refer to: * Leslie (name), a name and list of people with the given name or surname, including fictional characters Families * Clan Leslie, a Scottish clan with the motto "grip fast" * Leslie (Russian nobility), a Russian noble family of Scottish origin Places Canada * Leslie, Saskatchewan * Leslie Street, a road in Toronto and York Region, Ontario ** Leslie (TTC), a subway station ** Leslie Street Spit, an artificial spit in Toronto United States *Leslie, Arkansas *Leslie, Georgia *Leslie, Michigan *Leslie, Missouri *Leslie, West Virginia * Leslie, Wisconsin *Leslie Township, Michigan *Leslie Township, Minnesota Elsewhere * Leslie Dam, a dam in Warwick, Queensland, Australia * Leslie, Mpumalanga, South Africa * Leslie, Aberdeenshire, Scotland, see List of listed buildings in Leslie, Aberdeenshire * Leslie, Fife, Scotland, UK Other uses * Leslie speaker system * Leslie Motor Car company * Leslie Controls, Inc. * Leslie (singer) (born 1985), French singer S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molecular Genetics
Molecular genetics is a sub-field of biology that addresses how differences in the structures or expression of DNA molecules manifests as variation among organisms. Molecular genetics often applies an "investigative approach" to determine the structure and/or function of genes in an organism's genome using genetic screens. The field of study is based on the merging of several sub-fields in biology: classical Mendelian inheritance, Cell biology, cellular biology, molecular biology, biochemistry, and biotechnology. Researchers search for mutations in a gene or induce mutations in a gene to link a gene sequence to a specific phenotype. Molecular genetics is a powerful methodology for linking mutations to genetic conditions that may aid the search for treatments/cures for various genetics diseases. History For molecular genetics to develop as a discipline, several scientific discoveries were necessary. The discovery of DNA as a means to transfer the genetic code of life f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isozymes
In biochemistry, isozymes (also known as isoenzymes or more generally as multiple forms of enzymes) are enzymes that differ in amino acid sequence but catalyze the same chemical reaction. Isozymes usually have different kinetic parameters (e.g. different ''K''M values), or are regulated differently. They permit the fine-tuning of metabolism to meet the particular needs of a given tissue or developmental stage. In many cases, isozymes are encoded by homologous genes that have diverged over time. Strictly speaking, enzymes with different amino acid sequences that catalyse the same reaction are isozymes if encoded by different genes, or allozymes if encoded by different alleles of the same gene; the two terms are often used interchangeably. Introduction Isozymes were first described by R. L. Hunter and Clement Markert (1957) who defined them as ''different variants of the same enzyme having identical functions and present in the same individual''. This definition encompasses (1) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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