2018-01-21
3051.Evolutionary ideas evolution before Darwinism
2.Concepts about the development of early, medieval wildlife. Development of Biology in the Renaissance
3.Formation of evolutionary ideas in medieval Central Asia.
Evolutionary thought, the conception that species change over time, has roots in antiquity - in the ideas of the ancient Greeks, Romans, and Chinese as well as in medieval Islamic science. With the beginnings of modern biological taxonomy in the late 17th century, two opposed ideas influenced Western biological thinking: essentialism, the belief that every species has essential characteristics that are unalterable, a concept which had developed from medieval Aristotelian metaphysics, and that fit well with natural theology; and the development of the new anti-Aristotelian approach to modern science: as the Enlightenment progressed, evolutionary cosmology and the mechanical philosophyspread from the physical sciences to natural history. Naturalists began to focus on the variability of species; the emergence of paleontologywith the concept of extinction further undermined static views of nature. In the early 19th century Jean-Baptiste Lamarck (1744 – 1829) proposed his theory of the transmutation of species, the first fully formed theory of evolution.In 1858 Charles Darwin and Alfred Russel Wallace published a new evolutionary theory, explained in detail in Darwin's On the Origin of Species (1859). Unlike Lamarck, Darwin proposed common descent and a branching tree of life, meaning that two very different species could share a common ancestor. Darwin based his theory on the idea of natural selection: it synthesized a broad range of evidence from animal husbandry, biogeography, geology, morphology, and embryology. Debate over Darwin's work led to the rapid acceptance of the general concept of evolution, but the specific mechanism he proposed, natural selection, was not widely accepted until it was revived by developments in biology that occurred during the 1920s through the 1940s. Before that time most biologists regarded other factors as responsible for evolution. Alternatives to natural selection suggested during "the eclipse of Darwinism" (c. 1880 to 1920) included inheritance of acquired characteristics (neo-Lamarckism), an innate drive for change (orthogenesis), and sudden large mutations (saltationism). Mendelian genetics, a series of 19th-century experiments with pea plant variations rediscovered in 1900, was integrated with natural selection by Ronald Fisher, J. B. S. Haldane, and Sewall Wright during the 1910s to 1930s, and resulted in the founding of the new discipline of population genetics. During the 1930s and 1940s population genetics became integrated with other biological fields, resulting in a widely applicable theory of evolution that encompassed much of biology—the modern synthesis.Following the establishment of evolutionary biology, studies of mutation and genetic diversity in natural populations, combined with biogeography and systematics, led to sophisticated mathematical and causal models of evolution. Paleontology and comparative anatomy allowed more detailed reconstructions of the evolutionary history of life. After the rise of molecular genetics in the 1950s, the field of molecular evolution developed, based on protein sequences and immunological tests, and later incorporating RNA and DNAstudies. The gene-centered view of evolution rose to prominence in the 1960s, followed by the neutral theory of molecular evolution, sparking debates over adaptationism, the unit of selection, and the relative importance of genetic drift versus natural selection as causes of evolution.[2] In the late 20th-century, DNA sequencing led to molecular phylogenetics and the reorganization of the tree of life into the three-domain system by Carl Woese. In addition, the newly recognized factors of symbiogenesis and horizontal gene transferintroduced yet more complexity into evolutionary theory. Discoveries in evolutionary biology have made a significant impact not just within the traditional branches of biology, but also in other academic disciplines (for example: anthropology and psychology) and on society at large.
Greeks
Proposals that one type of animal, even humans, could descend from other types of animals, are known to go back to the first pre-Socratic Greek philosophers. Anaximander of Miletus (c. 610 – 546 BC) proposed that the first animals lived in water, during a wet phase of the Earth's past, and that the first land-dwelling ancestors of mankind must have been born in water, and only spent part of their life on land. He also argued that the first human of the form known today must have been the child of a different type of animal, because man needs prolonged nursing to live.[4] Empedocles (c. 490 – 430 BC), argued that what we call birth and death in animals are just the mingling and separations of elements which cause the countless "tribes of mortal things." Specifically, the first animals and plants were like disjointed parts of the ones we see today, some of which survived by joining in different combinations, and then intermixing during the development of the embryo,[a] and where "everything turned out as it would have if it were on purpose, there the creatures survived, being accidentally compounded in a suitable way. Other philosophers who became more influential in the Middle Ages, including Plato (c. 428/427 – 348/347 BC), Aristotle (384 – 322 BC), and members of the Stoic school of philosophy, believed that the types of all things, not only living things, were fixed by divine design.Plato was called by biologist Ernst Mayr "the great antihero of evolutionism,because he promoted belief in essentialism, which is also referred to as the theory of Forms. This theory holds that each natural type of object in the observed world is an imperfect manifestation of the ideal, form or "species" which defines that type. In his Timaeus for example, Plato has a character tell a story that the Demiurge created the cosmos and everything in it because, being good, and hence, "... free from jealousy, He desired that all things should be as like Himself as they could be." The creator created all conceivable forms of life, since "... without them the universe will be incomplete, for it will not contain every kind of animal which it ought to contain, if it is to be perfect." This "principle of plenitude"—the idea that all potential forms of life are essential to a perfect creation—greatly influenced Christian thought. However some historians of science have questioned how much influence Plato's essentialism had on natural philosophy by stating that many philosophers after Plato believed that species might be capable of transformation and that the idea that biologic species were fixed and possessed unchangeable essential characteristics did not become important until the beginning of biological taxonomy in the 17th and 18th centuries.Aristotle, the most influential of the Greek philosophers in Europe, was a student of Plato and is also the earliest natural historian whose work has been preserved in any real detail. His writings on biology resulted from his research into natural history on and around the island of Lesbos, and have survived in the form of four books, usually known by their Latin names, De anima (On the Soul), Historiaanimalium(History of Animals), De generationeanimalium (Generation of Animals), and De partibusanimalium (On the Parts of Animals). Aristotle's works contain accurate observations, fitted into his own theories of the body's mechanisms. However, for Charles Singer, "Nothing is more remarkable than [Aristotle's] efforts to [exhibit] the relationships of living things as a scalanaturae." This scalanaturae, described in Historiaanimalium, classified organisms in relation to a hierarchical "Ladder of Life" or "great chain of being," placing them according to their complexity of structure and function, with organisms that showed greater vitality and ability to move described as "higher organisms." Aristotle believed that features of living organisms showed clearly that they must have had what he called a final cause, that is to say that they had been designed for a purpose. He explicitly rejected the view of Empedocles that living creatures might have originated by chance.
Other Greek philosophers, such as Zeno of Citium (334 – 262 BC) the founder of the Stoic school of philosophy, agreed with Aristotle and other earlier philosophers that nature showed clear evidence of being designed for a purpose; this view is known as teleology. The Roman Stoic philosopher Cicero (106 – 43 BC) wrote that Zeno was known to have held the view, central to Stoic physics, that nature is primarily "directed and concentrated...to secure for the world...the structure best fitted for survival.Epicurus (341 – 270 BC) anticipated the idea of natural selection. The Roman philosopher and atomist Lucretius (c. 99 – 55 BC) explicated these ideas in his poem De rerumnatura(On the Nature of Things). In the Epicurean system, it was assumed that many living forms had been spontaneously generated from Gaia in the past, but that only the most functional forms had survived to have offspring. The Epicureans did not anticipate the full theory of evolution as we now know it, but seem to have postulated separate abiogenetic events for each species.
Chinese
Ancient Chinese thinkers such as Zhuang Zhou (c. 369 – 286 BC), a Taoist philosopher, expressed ideas on changing biologic species. According to Joseph Needham, Taoism explicitly denies the fixity of biological species and Taoist philosophers speculated that species had developed differing attributes in response to differing environments.[15] Taoism regards humans, nature and the heavens as existing in a state of "constant transformation" known as the Tao, in contrast with the more static view of nature typical of Western thought.[16]
Romans
Lucretius' poem De rerumnatura provides the best surviving explanation of the ideas of the Greek Epicurean philosophers. It describes the development of the cosmos, the Earth, living things, and human society through purely naturalistic mechanisms, without any reference to supernatural involvement. De rerumnatura would influence the cosmological and evolutionary speculations of philosophers and scientists during and after the Renaissance. This view was in strong contrast with the views of Roman philosophers of the Stoic school such as Cicero, Seneca the Younger (c. 4 BC – AD 65), and Pliny the Elder (23 – 79 AD) who had a strongly teleological view of the natural world that influenced Christian theology. Cicero reports that the peripatetic and Stoic view of nature as an agency concerned most basically with producing life "best fitted for survival" was taken for granted among the Hellenistic elite.
Augustine of Hippo
In line with earlier Greek thought, the 4th-century bishop and theologian, Augustine of Hippo, wrote that the creation story in the Book of Genesis should not be read too literally. In his book De Genesiadlitteram (On the Literal Meaning of Genesis), he stated that in some cases new creatures may have come about through the "decomposition" of earlier forms of life. For Augustine, "plant, fowl and animal life are not perfect... but created in a state of potentiality," unlike what he considered the theologically perfect forms of angels, the firmament and the human soul. Augustine's idea 'that forms of life had been transformed "slowly over time"' prompted Father Giuseppe Tanzella-Nitti, Professor of Theology at the Pontifical Santa Croce University in Rome, to claim that Augustine had suggested a form of evolution.
Henry Fairfield Osborn wrote in From the Greeks to Darwin (1894):
"If the orthodoxy of Augustine had remained the teaching of the Church, the final establishment of Evolution would have come far earlier than it did, certainly during the eighteenth instead of the nineteenth century, and the bitter controversy over this truth of Nature would never have arisen....Plainly as the direct or instantaneous Creation of animals and plants appeared to be taught in Genesis, Augustine read this in the light of primary causation and the gradual development from the imperfect to the perfect of Aristotle. This most influential teacher thus handed down to his followers opinions which closely conform to the progressive views of those theologians of the present day who have accepted the Evolution theory.In A History of the Warfare of Science with Theology in Christendom (1896), Andrew Dickson White wrote about Augustine's attempts to preserve the ancient evolutionary approach to the creation as follows:"For ages a widely accepted doctrine had been that water, filth, and carrion had received power from the Creator to generate worms, insects, and a multitude of the smaller animals; and this doctrine had been especially welcomed by St. Augustine and many of the fathers, since it relieved the Almighty of making, Adam of naming, and Noah of living in the ark with these innumerable despised species.In Augustine's De Genesi contra Manichæos, on Genesis he says: "To suppose that God formed man from the dust with bodily hands is very childish....God neither formed man with bodily hands nor did he breathe upon him with throat and lips." Augustine suggests in other work his theory of the later development of insects out of carrion, and the adoption of the old emanation or evolution theory, showing that "certain very small animals may not have been created on the fifth and sixth days, but may have originated later from putrefying matter." Concerning Augustine's De Trinitate (On the Trinity), White wrote that Augustine "...develops at length the view that in the creation of living beings there was something like a growth—that God is the ultimate author, but works through secondary causes; and finally argues that certain substances are endowed by God with the power of producing certain classes of plants and animals."
Although Greek and Roman evolutionary ideas died out in Europe after the fall of the Roman Empire, they were not lost to Islamic philosophersand scientists. In the Islamic Golden Age of the 8th to the 13th centuries, philosophers explored ideas about natural history. These ideas included transmutation from non-living to living: "from mineral to plant, from plant to animal, and from animal to man.In the medieval Islamic world, the scholar al-Jāḥiẓ (776 – c. 868) wrote his Book of Animals in the 9th century. Conway Zirkle, writing about the history of natural selection in 1941, said that an excerpt from this work was the only relevant passage he had found from an Arabian scholar. He provided a quotation describing the struggle for existence, citing a Spanish translation of this work: "The rat goes out for its food, and is clever in getting it, for it eats all animals inferior to it in strength," and in turn, it "has to avoid snakes and birds and serpents of prey, who look for it in order to devour it" and are stronger than the rat. Mosquitoes "know instinctively that blood is the thing which makes them live" and when they see an animal, "they know that the skin has been fashioned to serve them as food." In turn, flies hunt the mosquito "which is the food that they like best," and predators eat the flies. "All animals, in short, can not exist without food, neither can the hunting animal escape being hunted in his turn. Every weak animal devours those weaker than itself. Strong animals cannot escape being devoured by other animals stronger than they. And in this respect, men do not differ from animals, some with respect to others, although they do not arrive at the same extremes. In short, God has disposed some human beings as a cause of life for others, and likewise, he has disposed the latter as a cause of the death of the former. Al-Jāḥiẓ also wrote descriptions of food chains.Some of IbnKhaldūn's thoughts, according to some commentators, anticipate the biological theory of evolution. In 1377, IbnKhaldūn wrote the Muqaddimah in which he asserted that humans developed from the world of the monkeys," in a process by which "species become more numerous. In chapter 1 he writes: "This world with all the created things in it has a certain order and solid construction. It shows nexuses between causes and things caused, combinations of some parts of creation with others, and transformations of some existent things into others, in a pattern that is both remarkable and endless.The Muqaddimah also states in chapter 6:"We explained there that the whole of existence in (all) its simple and composite worlds is arranged in a natural order of ascent and descent, so that everything constitutes an uninterrupted continuum. The essences at the end of each particular stage of the worlds are by nature prepared to be transformed into the essence adjacent to them, either above or below them. This is the case with the simple material elements; it is the case with palms and vines, (which constitute) the last stage of plants, in their relation to snails and shellfish, (which constitute) the (lowest) stage of animals. It is also the case with monkeys, creatures combining in themselves cleverness and perception, in their relation to man, the being who has the ability to think and to reflect. The preparedness (for transformation) that exists on either side, at each stage of the worlds, is meant when (we speak about) their connection.
Nasīr al-DīnTūsī
In his Akhlaq-i-Nasri, Tusi put forward a basic theory for the evolution of species almost 600 years before Charles Darwin, the English naturalist credited with advancing the idea, was born. He begins his theory of evolution with the universe once consisting of equal and similar elements. According to Tusi, internal contradictions began appearing, and as a result, some substances began developing faster and differently from other substances. He then explains how the elements evolved into minerals, then plants, then animals, and then humans. Tusi then goes on to explain how hereditary variability was an important factor for biological evolution of living things:
"The organisms that can gain the new features faster are more variable. As a result, they gain advantages over other creatures. The bodies are changing as a result of the internal and external interactions.
Сontrol questions
1. What is evolution?
2. How do scientists explain how evolution occurs?
3. Did evolutionary theory exist before Darwin?
4. How do you think Darwin developed his theory?
5. Do you know of any other individuals who proposed theories on evolution?
