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115-440: Nicolas Camille Flammarion FRAS ( French: [nikɔla kamij flamaʁjɔ̃] ; 26 February 1842 – 3 June 1925) was a French astronomer and author. He was a prolific author of more than fifty titles, including popular science works about astronomy, several notable early science fiction novels, and works on psychical research and related topics. He also published the magazine L'Astronomie , starting in 1882. He maintained

230-737: A Royal Charter from William IV . In 1846 the RAS absorbed the Spitalfields Mathematical Society , which had been founded in 1717 but was suffering from a decline in membership and dwindling finances. The nineteen remaining members of the mathematical society were given free lifetime membership of the RAS; in exchange, their society's extensive library was donated to the RAS. Between 1835 and 1916 women were not allowed to become fellows, but Anne Sheepshanks , Lady Margaret Lindsay Huggins, Agnes Clerke , Annie Jump Cannon and Williamina Fleming were made honorary members. In 1886 Isis Pogson

345-470: A trade magazine for members, Astronomy & Geophysics . The history of journals published by the RAS (with abbreviations used by the Astrophysics Data System ) is: Full members of the RAS are styled Fellows, and may use the post-nominal letters FRAS . Fellowship is open to anyone over the age of 18 who is considered acceptable to the society. As a result of the society's foundation in

460-487: A DNA sequence within a chromosome is known as a locus . If the DNA sequence at a locus varies between individuals, the different forms of this sequence are called alleles. DNA sequences can change through mutations, producing new alleles. If a mutation occurs within a gene, the new allele may affect the trait that the gene controls, altering the phenotype of the organism. However, while this simple correspondence between an allele and

575-570: A GC-biased E. coli mutator strain in 1967, along with the proposal of the neutral theory , established the plausibility of mutational explanations for molecular patterns, which are now common in the molecular evolution literature. For instance, mutation biases are frequently invoked in models of codon usage. Such models also include effects of selection, following the mutation-selection-drift model, which allows both for mutation biases and differential selection based on effects on translation. Hypotheses of mutation bias have played an important role in

690-433: A campaign of misquoting and fabrication for the sake of sensational headlines. Flammarion was, in fact, the victim of a deliberate character assassination, in order to sell papers. Flammarion approached spiritism , psychical research and reincarnation from the viewpoint of the scientific method , writing, "It is by the scientific method alone that we may make progress in the search for truth. Religious belief must not take

805-514: A chromosome becoming duplicated (usually by genetic recombination ), which can introduce extra copies of a gene into a genome. Extra copies of genes are a major source of the raw material needed for new genes to evolve. This is important because most new genes evolve within gene families from pre-existing genes that share common ancestors. For example, the human eye uses four genes to make structures that sense light: three for colour vision and one for night vision ; all four are descended from

920-473: A cosmic version of metempsychosis . In Lumen , a human character meets the soul of an alien, able to cross the universe faster than light, that has been reincarnated on many different worlds, each with its own gallery of organisms and their evolutionary history. Other than that, his writing about other worlds adhered fairly closely to then current ideas in evolutionary theory and astronomy. Among other things, he believed that all planets went through more or less

1035-491: A lack of critical judgment in the estimation of evidence, and of an appreciation of the nature of the logical conditions which the study of these problems presents." After two years investigation into automatic writing he wrote that the subconscious mind is the explanation and there is no evidence for the spirit hypothesis. Flammarion believed in the survival of the soul after death but wrote that mediumship had not been scientifically proven. Even though Flammarion believed in

1150-402: A manner similar to a sequence of letters spelling out a sentence. Before a cell divides, the DNA is copied, so that each of the resulting two cells will inherit the DNA sequence. Portions of a DNA molecule that specify a single functional unit are called genes; different genes have different sequences of bases. Within cells, each long strand of DNA is called a chromosome . The specific location of

1265-446: A network of lines on its surface, which were named "canals" by Schiaparelli. These turned out to be an optical illusion due to the limited observing instruments of the time, as revealed by better telescopes in the 1920s. Camille, a contemporary of Schiaparelli, extensively researched the so-called "canals" during the 1880s and 1890s. Like American astronomer Percival Lowell , he thought the "canals" were artificial in nature and most likely

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1380-405: A nutrient in a long-term laboratory experiment , Flavobacterium evolving a novel enzyme that allows these bacteria to grow on the by-products of nylon manufacturing, and the soil bacterium Sphingobium evolving an entirely new metabolic pathway that degrades the synthetic pesticide pentachlorophenol . An interesting but still controversial idea is that some adaptations might increase

1495-611: A phenomenon termed de novo gene birth . The generation of new genes can also involve small parts of several genes being duplicated, with these fragments then recombining to form new combinations with new functions ( exon shuffling ). When new genes are assembled from shuffling pre-existing parts, domains act as modules with simple independent functions, which can be mixed together to produce new combinations with new and complex functions. For example, polyketide synthases are large enzymes that make antibiotics ; they contain up to 100 independent domains that each catalyse one step in

1610-535: A population are therefore more likely to be replaced by the offspring of parents with favourable characteristics for that environment. In the early 20th century, competing ideas of evolution were refuted and evolution was combined with Mendelian inheritance and population genetics to give rise to modern evolutionary theory. In this synthesis the basis for heredity is in DNA molecules that pass information from generation to generation. The processes that change DNA in

1725-575: A population include natural selection, genetic drift, mutation , and gene flow . All life on Earth—including humanity —shares a last universal common ancestor (LUCA), which lived approximately 3.5–3.8 billion years ago. The fossil record includes a progression from early biogenic graphite to microbial mat fossils to fossilised multicellular organisms . Existing patterns of biodiversity have been shaped by repeated formations of new species ( speciation ), changes within species ( anagenesis ), and loss of species ( extinction ) throughout

1840-430: A population is not critical, but instead a measure known as the effective population size. The effective population is usually smaller than the total population since it takes into account factors such as the level of inbreeding and the stage of the lifecycle in which the population is the smallest. The effective population size may not be the same for every gene in the same population. It is usually difficult to measure

1955-433: A population through neutral transitions due to the principles of excess capacity, presuppression, and ratcheting, and it has been applied in areas ranging from the origins of the spliceosome to the complex interdependence of microbial communities . The time it takes a neutral allele to become fixed by genetic drift depends on population size; fixation is more rapid in smaller populations. The number of individuals in

2070-734: A private observatory at Juvisy-sur-Orge , France. Camille Flammarion was born in Montigny-le-Roi , Haute-Marne , France. He was the brother of Ernest Flammarion (1846–1936), the founder of the Groupe Flammarion publishing house. In 1858 he became a professional at computery at the Paris Observatory . He was a founder and the first president of the Société astronomique de France , which originally had its own independent journal, BSAF ( Bulletin de la Société astronomique de France ) , which

2185-499: A range of genes from bacteria, fungi and plants. Viruses can also carry DNA between organisms, allowing transfer of genes even across biological domains . Large-scale gene transfer has also occurred between the ancestors of eukaryotic cells and bacteria, during the acquisition of chloroplasts and mitochondria . It is possible that eukaryotes themselves originated from horizontal gene transfers between bacteria and archaea . Some heritable changes cannot be explained by changes to

2300-566: A record four times each. Baily's eight years in the role are a record (Airy served for seven). Since 1876 no one has served for more than two years in total. The current president is Mike Lockwood, who began his term in May 2024 and will serve for two years. The highest award of the Royal Astronomical Society is its Gold Medal , which can be awarded for any purpose but most frequently recognises extraordinary lifetime achievement. Among

2415-430: A reduction in scope when it was discovered that (1) GC-biased gene conversion makes an important contribution to composition in diploid organisms such as mammals and (2) bacterial genomes frequently have AT-biased mutation. Contemporary thinking about the role of mutation biases reflects a different theory from that of Haldane and Fisher. More recent work showed that the original "pressures" theory assumes that evolution

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2530-415: A religious system based on the transmigration of souls believed to be reconcilable with both Christianity and pluralism. He was convinced that souls after the physical death pass from planet to planet and progressively improve at each new incarnation. In 1862 he published his first book, The Plurality of Inhabited Worlds , and was dismissed from his position at the Paris Observatory later the same year. It

2645-586: A significant influence on his childhood interest in science. Named after him Source: "Gallica search results" . Bibliothèque nationale de France . Retrieved 24 February 2022 . Fellow of the Royal Astronomical Society The society holds monthly scientific meetings in London, and the annual National Astronomy Meeting at varying locations in the British Isles . The RAS publishes

2760-452: A single ancestral gene. New genes can be generated from an ancestral gene when a duplicate copy mutates and acquires a new function. This process is easier once a gene has been duplicated because it increases the redundancy of the system; one gene in the pair can acquire a new function while the other copy continues to perform its original function. Other types of mutations can even generate entirely new genes from previously noncoding DNA,

2875-419: A single chromosome compared to expectations , which is called their linkage disequilibrium . A set of alleles that is usually inherited in a group is called a haplotype . This can be important when one allele in a particular haplotype is strongly beneficial: natural selection can drive a selective sweep that will also cause the other alleles in the haplotype to become more common in the population; this effect

2990-420: A species or population, in particular shifts in allele frequency and adaptation. Macroevolution is the outcome of long periods of microevolution. Thus, the distinction between micro- and macroevolution is not a fundamental one—the difference is simply the time involved. However, in macroevolution, the traits of the entire species may be important. For instance, a large amount of variation among individuals allows

3105-544: A species to rapidly adapt to new habitats , lessening the chance of it going extinct, while a wide geographic range increases the chance of speciation, by making it more likely that part of the population will become isolated. In this sense, microevolution and macroevolution might involve selection at different levels—with microevolution acting on genes and organisms, versus macroevolutionary processes such as species selection acting on entire species and affecting their rates of speciation and extinction. A common misconception

3220-411: A striking example are people with the inherited trait of albinism , who do not tan at all and are very sensitive to sunburn . Heritable characteristics are passed from one generation to the next via DNA , a molecule that encodes genetic information. DNA is a long biopolymer composed of four types of bases. The sequence of bases along a particular DNA molecule specifies the genetic information, in

3335-472: A system in which organisms interact with every other element, physical as well as biological , in their local environment. Eugene Odum , a founder of ecology, defined an ecosystem as: "Any unit that includes all of the organisms...in a given area interacting with the physical environment so that a flow of energy leads to clearly defined trophic structure, biotic diversity, and material cycles (i.e., exchange of materials between living and nonliving parts) within

3450-434: A table and an impression of a face in putty . Joseph McCabe did not find the evidence convincing. He noted that the impressions of faces in putty were always of Palladino's face and could have easily been made, and she was not entirely clear from the table in the levitation photographs. His book The Unknown (1900) received a negative review from the psychologist Joseph Jastrow who wrote "the work's fundamental faults are

3565-444: A time before there were many professional astronomers, no formal qualifications are required. However, around three quarters of fellows are professional astronomers or geophysicists . Most of the other fellows are postgraduate students studying for a PhD in those fields, but there are also advanced amateur astronomers , historians of science who specialise in those disciplines, and other related professionals. The society acts as

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3680-428: A trait works in some cases, most traits are influenced by multiple genes in a quantitative or epistatic manner. Evolution can occur if there is genetic variation within a population. Variation comes from mutations in the genome, reshuffling of genes through sexual reproduction and migration between populations ( gene flow ). Despite the constant introduction of new variation through mutation and gene flow, most of

3795-454: Is directional selection , which is a shift in the average value of a trait over time—for example, organisms slowly getting taller. Secondly, disruptive selection is selection for extreme trait values and often results in two different values becoming most common, with selection against the average value. This would be when either short or tall organisms had an advantage, but not those of medium height. Finally, in stabilising selection there

3910-442: Is more noticeable . Indeed, the evolution of microorganisms is particularly important to evolutionary research since their rapid reproduction allows the study of experimental evolution and the observation of evolution and adaptation in real time. Adaptation is the process that makes organisms better suited to their habitat. Also, the term adaptation may refer to a trait that is important for an organism's survival. For example,

4025-427: Is a byproduct of this process that may sometimes be adaptively beneficial. Gene flow is the exchange of genes between populations and between species. It can therefore be a source of variation that is new to a population or to a species. Gene flow can be caused by the movement of individuals between separate populations of organisms, as might be caused by the movement of mice between inland and coastal populations, or

4140-417: Is an inherited characteristic and an individual might inherit the "brown-eye trait" from one of their parents. Inherited traits are controlled by genes and the complete set of genes within an organism's genome (genetic material) is called its genotype . The complete set of observable traits that make up the structure and behaviour of an organism is called its phenotype . Some of these traits come from

4255-464: Is based on standing variation: when evolution depends on events of mutation that introduce new alleles, mutational and developmental biases in the introduction of variation (arrival biases) can impose biases on evolution without requiring neutral evolution or high mutation rates. Several studies report that the mutations implicated in adaptation reflect common mutation biases though others dispute this interpretation. Recombination allows alleles on

4370-407: Is called deep homology . During evolution, some structures may lose their original function and become vestigial structures. Such structures may have little or no function in a current species, yet have a clear function in ancestral species, or other closely related species. Examples include pseudogenes , the non-functional remains of eyes in blind cave-dwelling fish, wings in flightless birds,

4485-692: Is called genetic hitchhiking or genetic draft. Genetic draft caused by the fact that some neutral genes are genetically linked to others that are under selection can be partially captured by an appropriate effective population size. A special case of natural selection is sexual selection, which is selection for any trait that increases mating success by increasing the attractiveness of an organism to potential mates. Traits that evolved through sexual selection are particularly prominent among males of several animal species. Although sexually favoured, traits such as cumbersome antlers, mating calls, large body size and bright colours often attract predation, which compromises

4600-594: Is measured by an organism's ability to survive and reproduce, which determines the size of its genetic contribution to the next generation. However, fitness is not the same as the total number of offspring: instead fitness is indicated by the proportion of subsequent generations that carry an organism's genes. For example, if an organism could survive well and reproduce rapidly, but its offspring were all too small and weak to survive, this organism would make little genetic contribution to future generations and would thus have low fitness. If an allele increases fitness more than

4715-469: Is not quite clear if these two incidents are related to each other. In Real and Imaginary Worlds (1864) and Lumen (1887), he "describes a range of exotic species, including sentient plants which combine the processes of digestion and respiration. This belief in extraterrestrial life , Flammarion combined with a religious conviction derived, not from the Catholic faith upon which he had been raised, but from

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4830-700: Is second only to that of the Royal Observatory in Edinburgh in the UK. The RAS library is a major resource not just for the society but also the wider community of astronomers, geophysicists, and historians. The society promotes astronomy to members of the general public through its outreach pages for students, teachers, the public and media researchers. The RAS has an advisory role in relation to UK public examinations , such as GCSEs and A Levels . The RAS sponsors topical groups, many of them in interdisciplinary areas where

4945-421: Is selection against extreme trait values on both ends, which causes a decrease in variance around the average value and less diversity. This would, for example, cause organisms to eventually have a similar height. Natural selection most generally makes nature the measure against which individuals and individual traits, are more or less likely to survive. "Nature" in this sense refers to an ecosystem , that is,

5060-429: Is that evolution has goals, long-term plans, or an innate tendency for "progress", as expressed in beliefs such as orthogenesis and evolutionism; realistically, however, evolution has no long-term goal and does not necessarily produce greater complexity. Although complex species have evolved, they occur as a side effect of the overall number of organisms increasing, and simple forms of life still remain more common in

5175-447: Is the nearly neutral theory , according to which a mutation that would be effectively neutral in a small population is not necessarily neutral in a large population. Other theories propose that genetic drift is dwarfed by other stochastic forces in evolution, such as genetic hitchhiking, also known as genetic draft. Another concept is constructive neutral evolution (CNE), which explains that complex systems can emerge and spread into

5290-500: Is the change in the heritable characteristics of biological populations over successive generations. It occurs when evolutionary processes such as natural selection and genetic drift act on genetic variation, resulting in certain characteristics becoming more or less common within a population over successive generations. The process of evolution has given rise to biodiversity at every level of biological organisation . The scientific theory of evolution by natural selection

5405-495: Is the more common means of reproduction among eukaryotes and multicellular organisms. The Red Queen hypothesis has been used to explain the significance of sexual reproduction as a means to enable continual evolution and adaptation in response to coevolution with other species in an ever-changing environment. Another hypothesis is that sexual reproduction is primarily an adaptation for promoting accurate recombinational repair of damage in germline DNA, and that increased diversity

5520-439: Is the process by which traits that enhance survival and reproduction become more common in successive generations of a population. It embodies three principles: More offspring are produced than can possibly survive, and these conditions produce competition between organisms for survival and reproduction. Consequently, organisms with traits that give them an advantage over their competitors are more likely to pass on their traits to

5635-681: The Gold Medal of the Royal Astronomical Society . The RAS is the UK adhering organisation to the International Astronomical Union and a member of the UK Science Council . The society was founded in 1820 as the Astronomical Society of London to support astronomical research. At that time, most members were ' gentleman astronomers ' rather than professionals. It became the Royal Astronomical Society in 1831 on receiving

5750-681: The Harold Jeffreys Lectureship in geophysics , the George Darwin Lectureship in astronomy , and the Gerald Whitrow Lectureship in cosmology . Each year, the society grants a handful of free memberships for life (termed honorary fellowship) to prominent researchers resident outside the UK. The society occupies premises at Burlington House , London, where a library and meeting rooms are available to fellows and other interested parties. The society represents

5865-742: The Society for Psychical Research in October 1923 Flammarion summarized his views after 60 years of investigating paranormal phenomena . He wrote that he believed in telepathy , etheric doubles , the stone tape theory and "exceptionally and rarely the dead do manifest" in hauntings. He was also a member of the Theosophical Society . He was the first to suggest the names Triton and Amalthea for moons of Neptune and Jupiter , respectively, although these names were not officially adopted until many decades later. George Gamow cited Flammarion as having had

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5980-425: The neutral theory of molecular evolution most evolutionary changes are the result of the fixation of neutral mutations by genetic drift. In this model, most genetic changes in a population are thus the result of constant mutation pressure and genetic drift. This form of the neutral theory has been debated since it does not seem to fit some genetic variation seen in nature. A better-supported version of this model

6095-454: The product of a gene , or prevent the gene from functioning, or have no effect. About half of the mutations in the coding regions of protein-coding genes are deleterious — the other half are neutral. A small percentage of the total mutations in this region confer a fitness benefit. Some of the mutations in other parts of the genome are deleterious but the vast majority are neutral. A few are beneficial. Mutations can involve large sections of

6210-519: The professional body for astronomers and geophysicists in the UK and fellows may apply for the Science Council's Chartered Scientist status through the society. The fellowship passed 3,000 in 2003. In 2009 an initiative was launched for those with an interest in astronomy and geophysics but without professional qualifications or specialist knowledge in the subject. Such people may join the Friends of

6325-483: The scientific journals Monthly Notices of the Royal Astronomical Society , Geophysical Journal International and RAS Techniques and Instruments , along with the trade magazine Astronomy & Geophysics . The RAS maintains an astronomy research library , engages in public outreach and advises the UK government on astronomy education. The society recognises achievement in astronomy and geophysics by issuing annual awards and prizes, with its highest award being

6440-525: The "rectification of old rivers aimed at the general distribution of water to the surface of the continents." He assumed the planet was in an advanced stage of its habitability, and the canals were the product of an intelligent species attempting to survive on a dying world. When astronomers announced that the Earth would pass through the tail of Halley's Comet in May 1910, Flammarion was widely reported, in numerous American newspapers, as believing that toxic gases in

6555-657: The RAS, which offers popular talks, visits and social events. The Society organises an extensive programme of meetings: The biggest RAS meeting each year is the National Astronomy Meeting , a major conference of professional astronomers. It is held over 4–5 days each spring or early summer, usually at a university campus in the United Kingdom. Hundreds of astronomers attend each year. More frequent smaller 'highlight' meetings feature lectures about research topics in astronomy and geophysics, often given by winners of

6670-480: The United Kingdom, often in collaboration with other scientific societies and universities. The Royal Astronomical Society has a more comprehensive collection of books and journals in astronomy and geophysics than the libraries of most universities and research institutions. The library receives some 300 current periodicals in astronomy and geophysics and contains more than 10,000 books from popular level to conference proceedings. Its collection of astronomical rare books

6785-519: The ability of organisms to generate genetic diversity and adapt by natural selection (increasing organisms' evolvability). Adaptation occurs through the gradual modification of existing structures. Consequently, structures with similar internal organisation may have different functions in related organisms. This is the result of a single ancestral structure being adapted to function in different ways. The bones within bat wings, for example, are very similar to those in mice feet and primate hands, due to

6900-402: The adaptation of horses' teeth to the grinding of grass. By using the term adaptation for the evolutionary process and adaptive trait for the product (the bodily part or function), the two senses of the word may be distinguished. Adaptations are produced by natural selection. The following definitions are due to Theodosius Dobzhansky: Adaptation may cause either the gain of a new feature, or

7015-507: The alleles are subject to sampling error . This drift halts when an allele eventually becomes fixed, either by disappearing from the population or by replacing the other alleles entirely. Genetic drift may therefore eliminate some alleles from a population due to chance alone. Even in the absence of selective forces, genetic drift can cause two separate populations that begin with the same genetic structure to drift apart into two divergent populations with different sets of alleles. According to

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7130-540: The atmosphere. Sensation-seeking papers chose to quote only the latter part, leading to the widespread misconception that Flammarion actually believed it. On 1 February 1910, Flammarion published an update in the Herald , saying he wished to warn journalists against "accusing me of announcing the end of the world for May 19 next. The end of the world will not occur on May 19 next." He could not have made his position any clearer, yet many papers ignored this rebuttal, and continued

7245-441: The biosphere. For example, the overwhelming majority of species are microscopic prokaryotes , which form about half the world's biomass despite their small size and constitute the vast majority of Earth's biodiversity. Simple organisms have therefore been the dominant form of life on Earth throughout its history and continue to be the main form of life up to the present day, with complex life only appearing more diverse because it

7360-488: The change over time in this genetic variation. The frequency of one particular allele will become more or less prevalent relative to other forms of that gene. Variation disappears when a new allele reaches the point of fixation —when it either disappears from the population or replaces the ancestral allele entirely. Mutations are changes in the DNA sequence of a cell's genome and are the ultimate source of genetic variation in all organisms. When mutations occur, they may alter

7475-405: The conclusion that in some rare cases hauntings are caused by departed souls whilst others are caused by the "remote action of the psychic force of a living person". The book was reviewed by the magician Harry Houdini who wrote it "fails to supply adequate proof of the veracity of the conglomeration of hearsay it contains; it must, therefore, be a collection of myths." In a presidential address to

7590-400: The contrary. No satisfactory identification has been made. The communications obtained have always seemed to proceed from the mentality of the group, or when they are heterogeneous, from spirits of an incomprehensible nature. The being evoked soon vanishes when one insists on pushing him to the wall and having the heart out of his mystery. That souls survive the destruction of the body I have not

7705-403: The descent of all these structures from a common mammalian ancestor. However, since all living organisms are related to some extent, even organs that appear to have little or no structural similarity, such as arthropod , squid and vertebrate eyes, or the limbs and wings of arthropods and vertebrates, can depend on a common set of homologous genes that control their assembly and function; this

7820-400: The development of thinking about the evolution of genome composition, including isochores. Different insertion vs. deletion biases in different taxa can lead to the evolution of different genome sizes. The hypothesis of Lynch regarding genome size relies on mutational biases toward increase or decrease in genome size. However, mutational hypotheses for the evolution of composition suffered

7935-490: The direct control of genes include the inheritance of cultural traits and symbiogenesis . From a neo-Darwinian perspective, evolution occurs when there are changes in the frequencies of alleles within a population of interbreeding organisms, for example, the allele for black colour in a population of moths becoming more common. Mechanisms that can lead to changes in allele frequencies include natural selection, genetic drift, and mutation bias. Evolution by natural selection

8050-549: The earth itself. How many times do apparitions or manifestations occur? When illusions, auto-suggestions, hallucinations are eliminated what remains? Scarcely anything. Such an exceptional rarity as this pleads against the reality of apparitions. In the 1920s Flammarion changed some of his beliefs on apparitions and hauntings but still claimed there was no evidence for the spirit hypothesis of mediumship in Spiritism . In his 1924 book Les maisons hantées (Haunted Houses) he came to

8165-489: The evolutionary history of life on Earth. Morphological and biochemical traits tend to be more similar among species that share a more recent common ancestor , which historically was used to reconstruct phylogenetic trees , although direct comparison of genetic sequences is a more common method today. Evolutionary biologists have continued to study various aspects of evolution by forming and testing hypotheses as well as constructing theories based on evidence from

8280-414: The field or laboratory and on data generated by the methods of mathematical and theoretical biology . Their discoveries have influenced not just the development of biology but also other fields including agriculture, medicine, and computer science . Evolution in organisms occurs through changes in heritable characteristics—the inherited characteristics of an organism. In humans, for example, eye colour

8395-572: The first five women to be elected to Fellowship. One of the major activities of the RAS is publishing refereed journals. It publishes three primary research journals: Monthly Notices of the Royal Astronomical Society for topics in astronomy; Geophysical Journal International for topics in geophysics (in association with the Deutsche Geophysikalische Gesellschaft ); and RAS Techniques & Instruments for research methods in those disciplines. The society also publishes

8510-427: The fitness of an allele is not a fixed characteristic; if the environment changes, previously neutral or harmful traits may become beneficial and previously beneficial traits become harmful. However, even if the direction of selection does reverse in this way, traits that were lost in the past may not re-evolve in an identical form. However, a re-activation of dormant genes, as long as they have not been eliminated from

8625-472: The genome and were only suppressed perhaps for hundreds of generations, can lead to the re-occurrence of traits thought to be lost like hindlegs in dolphins, teeth in chickens, wings in wingless stick insects, tails and additional nipples in humans etc. "Throwbacks" such as these are known as atavisms . Natural selection within a population for a trait that can vary across a range of values, such as height, can be categorised into three different types. The first

8740-479: The genome of a species is very similar among all individuals of that species. However, discoveries in the field of evolutionary developmental biology have demonstrated that even relatively small differences in genotype can lead to dramatic differences in phenotype both within and between species. An individual organism's phenotype results from both its genotype and the influence of the environment it has lived in. The modern evolutionary synthesis defines evolution as

8855-468: The group is jointly sponsored by another learned society or professional body: The first person to hold the title of President of the Royal Astronomical Society was William Herschel , though he never chaired a meeting, and since then the post has been held by many distinguished astronomers. The post has generally had a term of office of two years, but some holders resigned after one year e.g. due to poor health. Francis Baily and George Airy were elected

8970-640: The idea of developmental bias . Haldane and Fisher argued that, because mutation is a weak pressure easily overcome by selection, tendencies of mutation would be ineffectual except under conditions of neutral evolution or extraordinarily high mutation rates. This opposing-pressures argument was long used to dismiss the possibility of internal tendencies in evolution, until the molecular era prompted renewed interest in neutral evolution. Noboru Sueoka and Ernst Freese proposed that systematic biases in mutation might be responsible for systematic differences in genomic GC composition between species. The identification of

9085-450: The interaction of its genotype with the environment while others are neutral. Some observable characteristics are not inherited. For example, suntanned skin comes from the interaction between a person's genotype and sunlight; thus, suntans are not passed on to people's children. The phenotype is the ability of the skin to tan when exposed to sunlight. However, some people tan more easily than others, due to differences in genotypic variation;

9200-473: The interests of astronomy and geophysics to UK national and regional, and European government and related bodies, and maintains a press office, through which it keeps the media and the public at large informed of developments in these sciences. The society allocates grants to worthy causes in astronomy and geophysics, and assists in the management of the Paneth Trust . Evolutionary theory Evolution

9315-512: The level of the individual organism are genes called transposons , which can replicate and spread throughout a genome. Selection at a level above the individual, such as group selection , may allow the evolution of cooperation. Genetic drift is the random fluctuation of allele frequencies within a population from one generation to the next. When selective forces are absent or relatively weak, allele frequencies are equally likely to drift upward or downward in each successive generation because

9430-452: The longer term, evolution produces new species through splitting ancestral populations of organisms into new groups that cannot or will not interbreed. These outcomes of evolution are distinguished based on time scale as macroevolution versus microevolution. Macroevolution refers to evolution that occurs at or above the level of species, in particular speciation and extinction, whereas microevolution refers to smaller evolutionary changes within

9545-405: The loss of an ancestral feature. An example that shows both types of change is bacterial adaptation to antibiotic selection, with genetic changes causing antibiotic resistance by both modifying the target of the drug, or increasing the activity of transporters that pump the drug out of the cell. Other striking examples are the bacteria Escherichia coli evolving the ability to use citric acid as

9660-458: The mechanics in developmental plasticity and canalisation . Heritability may also occur at even larger scales. For example, ecological inheritance through the process of niche construction is defined by the regular and repeated activities of organisms in their environment. This generates a legacy of effects that modify and feed back into the selection regime of subsequent generations. Other examples of heritability in evolution that are not under

9775-408: The movement of pollen between heavy-metal-tolerant and heavy-metal-sensitive populations of grasses. Gene transfer between species includes the formation of hybrid organisms and horizontal gene transfer . Horizontal gene transfer is the transfer of genetic material from one organism to another organism that is not its offspring; this is most common among bacteria. In medicine, this contributes to

9890-427: The next generation than those with traits that do not confer an advantage. This teleonomy is the quality whereby the process of natural selection creates and preserves traits that are seemingly fitted for the functional roles they perform. Consequences of selection include nonrandom mating and genetic hitchhiking . The central concept of natural selection is the evolutionary fitness of an organism. Fitness

10005-499: The offspring of sexual organisms contain random mixtures of their parents' chromosomes that are produced through independent assortment. In a related process called homologous recombination , sexual organisms exchange DNA between two matching chromosomes. Recombination and reassortment do not alter allele frequencies, but instead change which alleles are associated with each other, producing offspring with new combinations of alleles. Sex usually increases genetic variation and may increase

10120-456: The other alleles of that gene, then with each generation this allele has a higher probability of becoming common within the population. These traits are said to be "selected for ." Examples of traits that can increase fitness are enhanced survival and increased fecundity . Conversely, the lower fitness caused by having a less beneficial or deleterious allele results in this allele likely becoming rarer—they are "selected against ." Importantly,

10235-578: The overall process, like a step in an assembly line. One example of mutation is wild boar piglets. They are camouflage coloured and show a characteristic pattern of dark and light longitudinal stripes. However, mutations in the melanocortin 1 receptor ( MC1R ) disrupt the pattern. The majority of pig breeds carry MC1R mutations disrupting wild-type colour and different mutations causing dominant black colouring. In asexual organisms, genes are inherited together, or linked , as they cannot mix with genes of other organisms during reproduction. In contrast,

10350-455: The past. He also believed in 1907 that a seven-tailed comet was heading toward Earth. In 1910, for the appearance of Halley's Comet , he was widely but falsely reported as believing the gas from the comet's tail "would impregnate [the Earth’s] atmosphere and possibly snuff out all life on the planet". As a young man, Flammarion was exposed to two significant social movements in the western world:

10465-578: The place of impartial analysis. We must be constantly on our guard against illusions." He was very close to the French author Allan Kardec , who founded Spiritism . Flammarion had studied mediumship and wrote, "It is infinitely to be regretted that we cannot trust the loyalty of mediums. They almost always cheat". However, Flammarion, a believer in psychic phenomena, attended séances with Eusapia Palladino and claimed that some of her phenomena were genuine. He produced in his book alleged levitation photographs of

10580-527: The presence of hip bones in whales and snakes, and sexual traits in organisms that reproduce via asexual reproduction. Examples of vestigial structures in humans include wisdom teeth , the coccyx , the vermiform appendix , and other behavioural vestiges such as goose bumps and primitive reflexes . However, many traits that appear to be simple adaptations are in fact exaptations : structures originally adapted for one function, but which coincidentally became somewhat useful for some other function in

10695-464: The process. One example is the African lizard Holaspis guentheri , which developed an extremely flat head for hiding in crevices, as can be seen by looking at its near relatives. However, in this species, the head has become so flattened that it assists in gliding from tree to tree—an exaptation. Within cells, molecular machines such as the bacterial flagella and protein sorting machinery evolved by

10810-494: The rate of evolution. The two-fold cost of sex was first described by John Maynard Smith . The first cost is that in sexually dimorphic species only one of the two sexes can bear young. This cost does not apply to hermaphroditic species, like most plants and many invertebrates . The second cost is that any individual who reproduces sexually can only pass on 50% of its genes to any individual offspring, with even less passed on as each new generation passes. Yet sexual reproduction

10925-750: The recipients best known to the general public are Albert Einstein in 1926, and Stephen Hawking in 1985. Other awards are for particular topics in astronomy or geophysics research, which include the Eddington Medal , the Herschel Medal , the Chapman Medal and the Price Medal . Beyond research, there are specific awards for school teaching (Patrick Moore Medal), public outreach (Annie Maunder Medal), instrumentation ( Jackson-Gwilt Medal ) and history of science (Agnes Mary Clerke Medal). Lectureships include

11040-408: The relative importance of selection and neutral processes, including drift. The comparative importance of adaptive and non-adaptive forces in driving evolutionary change is an area of current research . Mutation bias is usually conceived as a difference in expected rates for two different kinds of mutation, e.g., transition-transversion bias, GC-AT bias, deletion-insertion bias. This is related to

11155-490: The same day as each highlight meeting. These are aimed at professional scientists in a particular research field, and allow several speakers to present new results or reviews of scientific fields. Usually two discussion meetings on different topics (one in astronomy and one in geophysics) take place simultaneously at different locations within Burlington House, prior to the day's highlight meeting. They are free for members of

11270-458: The same stages of development, but at different rates depending on their sizes. The fusion of science, science fiction and the spiritual influenced other readers as well; "With great commercial success he blended scientific speculation with science fiction to propagate modern myths such as the notion that “superior” extraterrestrial species reside on numerous planets, and that the human soul evolves through cosmic reincarnation. Flammarion's influence

11385-417: The same strand of DNA to become separated. However, the rate of recombination is low (approximately two events per chromosome per generation). As a result, genes close together on a chromosome may not always be shuffled away from each other and genes that are close together tend to be inherited together, a phenomenon known as linkage . This tendency is measured by finding how often two alleles occur together on

11500-552: The sequence of nucleotides in the DNA. These phenomena are classed as epigenetic inheritance systems. DNA methylation marking chromatin , self-sustaining metabolic loops, gene silencing by RNA interference and the three-dimensional conformation of proteins (such as prions ) are areas where epigenetic inheritance systems have been discovered at the organismic level. Developmental biologists suggest that complex interactions in genetic networks and communication among cells can lead to heritable variations that may underlay some of

11615-465: The shadow of a doubt. But that they manifest themselves by the processes employed in séances the experimental method has not yet given us absolute proof. I add that this hypothesis is not at all likely. If the souls of the dead are about us, upon our planet, the invisible population would increase at the rate of 100,000 a day, about 36 millions a year, 3 billions 620 millions in a century, 36 billions in ten centuries, etc.—unless we admit re-incarnations upon

11730-551: The society's awards . They are normally held in Burlington House in London on the afternoon of the second Friday of each month from October to May. The talks are intended to be accessible to a broad audience of astronomers and geophysicists, and are free for anyone to attend (not just members of the society). Formal reports of the meetings are published in The Observatory magazine. Specialist discussion meetings are held on

11845-552: The society, but charge a small entry fee for non-members. The RAS holds a regular programme of public lectures aimed at a general, non-specialist, audience. These are mostly held on Tuesdays once a month, with the same talk given twice: once at lunchtime and once in the early evening. The venues have varied, but are usually in Burlington House or another nearby location in central London. The lectures are free, though some popular sessions require booking in advance. The society occasionally hosts or sponsors meetings in other parts of

11960-406: The spread of antibiotic resistance , as when one bacteria acquires resistance genes it can rapidly transfer them to other species. Horizontal transfer of genes from bacteria to eukaryotes such as the yeast Saccharomyces cerevisiae and the adzuki bean weevil Callosobruchus chinensis has occurred. An example of larger-scale transfers are the eukaryotic bdelloid rotifers , which have received

12075-640: The survival of individual males. This survival disadvantage is balanced by higher reproductive success in males that show these hard-to-fake , sexually selected traits. Evolution influences every aspect of the form and behaviour of organisms. Most prominent are the specific behavioural and physical adaptations that are the outcome of natural selection. These adaptations increase fitness by aiding activities such as finding food, avoiding predators or attracting mates. Organisms can also respond to selection by cooperating with each other, usually by aiding their relatives or engaging in mutually beneficial symbiosis . In

12190-532: The survival of the soul after death he did not believe in the spirit hypothesis of Spiritism, instead he believed that Spiritist activities such as ectoplasm and levitations of objects could be explained by an unknown " psychic force " from the medium. He also believed that telepathy could explain some paranormal phenomena. In his book Mysterious Psychic Forces (1909) he wrote: This is very far from being demonstrated. The innumerable observations which I have collected during more than forty years all prove to me

12305-642: The system...." Each population within an ecosystem occupies a distinct niche , or position, with distinct relationships to other parts of the system. These relationships involve the life history of the organism, its position in the food chain and its geographic range. This broad understanding of nature enables scientists to delineate specific forces which, together, comprise natural selection. Natural selection can act at different levels of organisation , such as genes, cells, individual organisms, groups of organisms and species. Selection can act at multiple levels simultaneously. An example of selection occurring below

12420-591: The tail might "snuff out all life on the planet". In fact, he said no such thing. In an article in the New York Herald in November 1909, responding to such claims by others, he stated that "The poisoning of humanity by deleterious gases is improbable", and correctly stated that the matter in the comet's tail is so tenuous that it would have no noticeable effect. However, he also indulged in a "thought experiment" about what might happen if it did inject various gases into

12535-491: The tail of Halley's Comet would be poisonous for earth life. Camille was a brother of Ernest Flammarion and Berthe Martin-Flammarion, and uncle of a woman named Zelinda. His first wife was Sylvie Petiaux-Hugo Flammarion , and his second wife was Gabrielle Renaudot Flammarion , also a noted astronomer. Beginning with Giovanni Schiaparelli 's 1877 observations, 19th-century astronomers observing Mars believed they saw

12650-443: The thoughts and ideas of Darwin and Lamarck and the rising popularity of spiritism with spiritualist churches and organizations appearing all over Europe. He has been described as an "astronomer, mystic and storyteller" who was "obsessed by life after death, and on other worlds, and [who] seemed to see no distinction between the two". He was influenced by Jean Reynaud (1806–1863) and his Terre et ciel (1854), which described

12765-466: The writings of Jean Reynaud and their emphasis upon the transmigration of souls. Man he considered to be a “citizen of the sky,” other worlds “studios of human work, schools where the expanding soul progressively learns and develops, assimilating gradually the knowledge to which its aspirations tend, approaching thus evermore the end of its destiny.” His psychical studies also influenced some of his science fiction , where he would write about his beliefs in

12880-887: Was conceived independently by two British naturalists, Charles Darwin and Alfred Russel Wallace , in the mid-19th century as an explanation for why organisms are adapted to their physical and biological environments. The theory was first set out in detail in Darwin's book On the Origin of Species . Evolution by natural selection is established by observable facts about living organisms: (1) more offspring are often produced than can possibly survive; (2) traits vary among individuals with respect to their morphology , physiology , and behaviour; (3) different traits confer different rates of survival and reproduction (differential fitness ); and (4) traits can be passed from generation to generation ( heritability of fitness). In successive generations, members of

12995-670: Was first published in 1887. In January 1895, after 13 volumes of L'Astronomie and 8 of BSAF , the two merged, making L’Astronomie its bulletin. The 1895 volume of the combined journal was numbered 9, to preserve the BSAF volume numbering, but this had the consequence that volumes 9 to 13 of L'Astronomie can each refer to two different publications five years apart. The " Flammarion engraving " first appeared in Flammarion's 1888 edition of L’Atmosphère . In 1907, he wrote that he believed that dwellers on Mars had tried to communicate with Earth in

13110-454: Was great, not just on the popular thought of his day, but also on later writers with similar interests and convictions." In the English translation of Lumen , Brian Stableford argues that both Olaf Stapledon and William Hope Hodgson have likely been influenced by Flammarion. Arthur Conan Doyle 's The Poison Belt , published 1913, also has a lot in common with Flammarion's supposed worries that

13225-541: Was the first woman to attempt election as a fellow of the RAS, being nominated (unsuccessfully) by her father and two other fellows. All fellows had been male up to this time and her nomination was withdrawn when lawyers claimed that under the provisions of the society's royal charter, fellows were only referred to as he and as such had to be men. A Supplemental Charter in 1915 opened up fellowship to women. On 14 January 1916, Mary Adela Blagg , Ella K Church, A Grace Cook , Irene Elizabeth Toye Warner and Fiammetta Wilson were

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