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 biological taxonomy in the late 17th century, Western biological thinking was influenced by two opposed ideas.
Evolutionary biologist Massimo Pigliucci and philosopher Jonathan Kaplan have proposed that the term "species" is in fact what philosophers call a "family resemblance predicate". This is when being an instance of a general kind referred to by a word (the classic philosophical example is "game") has many criteria, and as long as most of them are met by a particular instance, it is a part of the kind.
The English economist Thomas Malthus had the idea that since more creatures are born each year than the number that die, populations are held in check by famine and disease. This sparked Darwin's idea about natural selection. Perhaps evolution was not a surprising idea, but an idea whose time had come. After all, Alfred Russell Wallace sent a letter to Darwin proposing very similar ideas before Darwin had published his theory.
The leading biological scientist of the mid 18th century was the Swedish botanist Karl von Linné (Carolus Linnaeus click this icon to hear the name pronounced in Latin). His 180 books are filled with precise descriptions of nature, but he did little analysis or interpretation. This is to be expected since Linnaeus apparently believed that he was just revealing the unchanging order of life created by God. The goal of documenting change in nature would not have made sense to him. Late in his life, however, he was troubled by the fact that plant hybrids could be created by cross pollination. These were varieties that had not existed before. Linnaeus stopped short of concluding that these plants had evolved.
In his studies on the Galapagos Islands, Darwin observed patterns in animals and plants that suggested to him that species changed over time to produce new species. Darwin collected several species of finches. The species were all similar, but each had developed beaks and bills specialized to catch food in a different way...
Belief in species change, or transmutationism, slowly began to emerge during the Enlightenment . This period saw the emergence of the belief in a progressive world, both scientific and social. It also saw the beginnings of the new science of geology. Geological theories suggested that fossils were of organic (once-living) origin and that uniform or constant processes rather than catastrophic or one-time events had shaped Earth's history.
Charles Darwin's grandfather Erasmus Darwin (1731-1802) was also a distinguished naturalist with his own intriguing ideas about evolution. While he never thought of natural selection, he did argue that all life could a have a single common ancestor, though he struggled with the concepts of a mechanism for this descent. He also discussed the effects of competition and sexual selection (see Other Types of Selection) on possible changes in species. Like Lamarck, Erasmus Darwin subscribed to a theory stating that the use or disuse of parts could in itself make them grow or shrink, and that unconscious striving by the organism was responsible for adaptation
The history of evolution long predates Darwin and his theory. The belief in a changing or dynamic universe can be first seen in ancient Greek philosophy. Heraclitus (c. 500 B . C . E . ), also known as the "flux philosopher," believed that change was a fundamental property of the universe. His successor, Empedocles (c.. 392–432 B.C.E.), first articulated a crude but dynamic theory that postulated that the origin of life had taken place in a manner that suggested evolution.
Some of the most interesting questions for evolutionary theory center on the appearance of our own species, Homo sapiens, which probably evolved in the Great Rift Valley of eastern Africa between 2.6 million and 1.7 million years ago. Since the 1980s, scientists have suggested that climate-related changes in the environment drove evolutionary events in human history, including the appearance of bipedal walking, larger brains, and behavioral adaptability, as well as the first migrations from Africa to other continents.
The traditional Judeo-Christian version of creationism click this icon to hear the preceding term pronounced was strongly reinforced by James Ussher click this icon to hear the name pronounced, a 17th century Anglican archbishop of Armagh in Northern Ireland. By counting the generations of the Bible and adding them to modern history, he fixed the date of creation at October 23, 4004 B.C. During Ussher's lifetime, debate focused only on the details of his calculations rather than on the approach. Dr. Charles Lightfoot of Cambridge University in England had the last word. He proclaimed that the time of creation was 9:00 A.M. on October 23, 4004 B.C.
THE THEORY of evolution, formalized by Charles Darwin, is as much theory as is the theory of gravity, or the theory of relativity. Unlike theories of physics, biological theories (especially evolution) have been argued long and hard in socio-political arenas. The history of thought about evolution in general and paleontological contributions specifically are often useful to the workers of today. Science, like any iterative process, draws heavily from its history.