Raven Biology Of Plants 9th Edition Pdf
Shanae Maerz
For four decades, he headed the Missouri Botanical Garden, an institution he nurtured into a world-class center for botanical research, education and horticultural display. He retired as president in 2010 and assumed the role of president emeritus and consultant through 2014.
Described by Time magazine as a "Hero for the Planet," Raven champions research around the world to preserve endangered plants and is a leading advocate for conservation and a sustainable environment.
In recognition of his work in science and conservation, Raven is the recipient of numerous prizes and awards, including the prestigious International Prize for Biology from the government of Japan and the U.S. National Medal of Science, the country's highest award for scientific accomplishment. He has held Guggenheim and John D. and Catherine T. MacArthur Foundation fellowships. He initiated and c0-chaired the Flora of China project, which will be completed in 50 volumes in 2013.
Raven was a member of President Bill Clinton's Committee of Advisors on Science and Technology. He also served for 12 years as home secretary of the National Academy of Sciences and is a member of the academies of science in Argentina, Brazil, China, Denmark, India, Italy, Mexico, Russia, Sweden, the U.K. and several other countries.
The author of numerous books and reports, both popular and scientific, Raven co-wrote Biology of Plants, an internationally best-selling textbook, now in its sixth edition. He also co-authored Environment, a leading textbook on the environment.
On June 13, 1936, Raven was born in Shanghai, China, to American parents, Walter Francis Raven and Isabelle Marion Breen. His father's uncle Frank Jay Raven was, for a time, one of the wealthiest Americans in China but was later jailed in a banking scandal.[3][4] That incident and Japanese aggression in China led the Raven family to return to San Francisco, California, in the late 1930s.
After becoming a member of the California Academy of Sciences while still a youth, Raven went on to graduate with a BSc in biology from the University of California, Berkeley, in 1957 and a Ph.D. in botany from the University of California, Los Angeles, in 1960.
After teaching at Stanford University, Raven went on to become Director of the Missouri Botanical Garden in 1971. In 2006, his position was renamed President and Director. Raven announced his plans to retire in 2011, to coincide with his 75th birthday and his 40th year at the garden. Peter Wyse Jackson was appointed as Raven's successor at the Missouri Botanical Garden in September 2010.
Raven is possibly best known for his work "Butterflies and Plants: A Study in Coevolution", published in the journal Evolution in 1964, which he coauthored with Paul R. Ehrlich. Since then he has authored numerous scientific and popular papers, many on the evening primrose family, Onagraceae. Raven is also an author of the widely used textbook Biology of Plants, now in its eighth edition, coauthored with Ray F. Evert and Susan E. Eichhorn (both of University of Wisconsin, Madison).
In 2000, the American Society of Plant Taxonomists established the Peter Raven Award in his honor to be conferred to authors with outstanding contributions to plant taxonomy and "for exceptional efforts at outreach to non-scientists".
Raven has published more than 700 articles, books, and monographs covering topics in Evolution, Taxonomy and Systematics, Biogeography, Coevolution, Plant Conservation, Ethnobotany, and Public Policy, including several text books.[5]
During his early years he was associated with and led Sierra Club outings for several weeks at a time, after which he published "Base Camp Reports." Published from 1950 to 1956, these reports covered a wide range of subjects, including plant lists, insects, and ecology. His first such report, at the age of 14, summarized 506 plant collections representing 337 species collected in the Sierra Nevada Mountains in Inyo and Fresno Counties. G. Ledyard Stebbins was a counselor on this particular trip, identified by Raven as Prof. G. L. "Led" Stebbins.[6]
In 1950 Raven, at the age of 14, had collected a plant called C. rubicunda.[12] In the early 1950s, in the course of revising the genus Clarkia Harlan Lewis and his wife Margaret Lewis discovered the herbarium specimen collected by Raven.[12] They visited him in 1952 when he was 16, and wanted to know where the collection was made.[12] Lewis eventually located the new species, and in 1958 Lewis and Raven[13] published a botanical description of this plant, called C. franciscana, which was morphologically very closely related to C. rubicunda and C. amoena.
While a graduate student at the University of California, Los Angeles, Raven and Harlan Lewis published a major paper in 1958 on the evolution of C. franciscana, and generalized to what was by then a general a pattern of speciation in Clarkia.[14] They concluded that C. franciscana had evolved from Clarkia rubicunda; and they asserted that C. franciscana's origin mirrored a recurring theme in Clarkia of a derived species showing a close morphological similarity to a parental species, the derived species being geographically proximal, but differing from the parent by chromosomal differences and showing interspecific sterility. Further, they hypothesized that such speciation in Clarkia was rapid, and perhaps occurred within the last 12,000 years.
Following his early publication in 1958 on evolution of C. franciscana, Raven went on to publish many papers on evolutionary topics. While at Stanford University, with Paul R. Ehrlich, he coined the term coevolution after a 1964 review of butterflies and their food plants.[15]
In a 1969 paper Ehrlich and Raven were also critical of the idea that the definition of species as advocated by Ernst Mayr, Theodosius Dobzhansky, and G. Ledyard Stebbins had very little meaning for plants.[16]
In 1978 Sussman and Raven[17] advanced the idea that nonflying mammals, such as primates and marsupials, could have been significant pollinators but were outcompeted by nectar-feeding birds and bats. Any coevolved relationships between flowering plant species and non-flying mammal pollinators that persist at the present would appear to be "living fossils, which have a great deal to tell us about the evolution of both the mammals, including some of our antecedents, and of the flowering plants."
Raven wrote a review of the plant population data as of 1979, and identified several themes that he felt had potential for future research, including the above theme of the species problem.[18] He went on to assert that developmental biology would be more important in the future He advocated another theme, that being that funding should be provided for study on a few species rather than spread amongst many in order to solve population biology problems:[18]
In 1980 Raven continued discussing problems associated with defining species in plants.[19] He discussed the widespread ability of plant species to hybridize, especially in perennial plants, and the historical observations of such back to 1717. He used as examples of perennial plants in the genera Epilobium, Scaevola, Bidens, and Ceanothus as examples of plants that appeared to use hybridization as a means to adapting to new environments. He stated "If the hybrids are particularly favored in specific ecological situations, asexual reproduction, polyploidy, or simply autogamy may favor the perpetuation of specific genotypes through a narrowing of the spectrum of genetic recombination characteristic of the population. No general conclusions about the most appropriate way to treat these populations taxonomically appear to be possible." In annual plants, using examples from Clarkia, he asserted that several species of Clarkia often occur sympatrically, yet hybrids are very rare in the wild," and that much of the sterility is due to chromosomal repatterning between species."
In 1980 Raven and coauthors reviewed the literature concerning fungal symbiosis in vascular plants.[20] They reviewed two kinds of fungal-plant associations: ectomycorrhizal and endomycorrhizal. They reported that endomycorrhizal fungi, which penetrate plant cells, are found in 80% of all vascular plants, including ferns, gymnosperms, and angiosperms, and are found in forests of high species richness. On the other hand, ectomycorrhizal fungi, which do not penetrate plant cells, occur in forests of low species richness, are usually in temperate forests, or infertile soils of the tropics. Further, they hypothesized that ectomycorrhizal forests have expanded through the Middle Cretaceous at the expense of endomycorrhizal forests.
Raven's Ph.D. thesis was on a genus within the Onagraceae, and his interest on the evolution of plants within this family as well as the Myrtales runs through his entire career.[12][5] In 1988 he published a review of the Onagraceae, covering its taxonomy, evolution, cytogenetics, anatomy, breeding systems, and geographic distribution.[21] He asserted that the family was the best known plant family of its size, and proposed that further studies of the family would be useful in understanding of "variation and evolution of plants in the future."
Raven showed an early interest in plant disjunctions prior to the wide acceptance of plate tectonic theory of the late 1960s,[22] and was an early adopter of plate tectonics in explaining plant disjunctions by the early 1970s.[23]
In 1963 Raven published a review of amphitropical distributions of plant species in North and South America.[22] He divided species into three groups: biopolar or high-latitude species, temperate species, and desert species.
In 1974, with Daniel I. Axelrod, Raven published an extensive article on plant and animal biogeography in the context of plate tectonics.[25] They stated that the new plate tectonic theory "did not require any new modifications of previously established major principles of evolution...however there were new principles of biogeography..."[citation needed]
e59dfda104