Evolution Monograph

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evolution “Scientific knowledge is in perpetual evolution; it finds itself changed from one day to the next.� - Jean Piaget


& Variation Selection


&

“Evolution thus is merely contingent on certain processes articulated by Darwin: variation and selection.” - Ernst Mayr

Evolution is the process by which different kinds of living organisms are believed to have developed from earlier forms over millions of years. Charles Robert Darwin FRS was an English naturalist. He established that all species of life have descended over time from common ancestry, and proposed the scientific theory that this branching pattern of evolution resulted from a process that he called natural selection. He published his theory with compelling evidence for evolution in his 1859 book On the Origin of Species, overcoming scientific rejection of earlier concepts of transmutation of species. By the 1870s the scientific community and much of the general public accepted evolution as a fact. However, many favoured competing explanations and it was not until the emergence of the modern evolutionary synthesis from the 1930s to the 1950s that a broad consensus developed that natural selection was the basic mechanism of evolution. In modified form, Darwin’s scientific discovery is the unifying theory of the life sciences, explaining the diversity of life. Darwin’s early interest in nature led him to neglect his medical education at the University of Edinburgh; instead, he helped to investigate marine invertebrates. Studies at the University of Cambridge encouraged his passion for natural science. By the 1870s the scientific community and much of the general public accepted evolution as a fact. However, many favoured competing explanations and it was not until the emergence of the modern evolutionary synthesis from the 1930s to the 1950s that a broad consensus developed that natural selection was the basic mechanism of evolution. 1


“Evolution is a Tinkerer� - Francois Jacob

Evolution is a process of gradual change or transformation, and is commonly used to refer to biological, genetic or organic evolution, the changes in populations of organisms over generations, the processes by which such changes occur, and theories regarding them. Offspring differ from their parents in various ways. When these differences are helpful, the offspring have a greater chance of surviving and reproducing, making the differences more common in the next generation. In this way, differences can accumulate over time, leading to major changes in a population.

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Leaves turning to Autumn Three factors influence autumn leaf color; leaf pigments, length of night and weather. The timing of color change and leaf fall are primarily regulated by the calendar

Major scientific theories of evolution state that all living things on Earth are descended, at some point in the distant past, from a single common ancestor, and others posit the possibility of extraterrestrial genetic material delivered through asteroids and comets. Since the beginnings of life, divergent evolution has produced numerous different species as life has found a variety of ways to survive and flourish. Evolution is the cause of speciation, whereby a single ancestral species splits into two or more different species. Speciation is visible in anatomical, genetic and other similarities between groups of organisms, geographical distribution of related species, the fossil record and the recorded genetic changes in living organisms over many generations. Common descent stretches back over 3.5 billion years during which life has existed on earth. Both evolution within populations and speciation between them are thought to occur in multiple ways such as slowly, steadily and gradually over time or rapidly from one long static state to another.

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Large oak tree

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“Breaking up is a natural evolution when you try to figure out what you want in life. If you’re with an individual who isn’t moving in the same direction and at the same rate that you are, it ain’t going to work.” - Usher Raymond

Evolution is the gradual development of something: the forms of written languages undergo constant evolution. It is a gradual process of change and development; a pattern of movements or manoeuvres: flocks of waders often perform aerial evolutions. A pattern, from the French patron, is a type of theme of recurring events or objects, sometimes referred to as elements of a set of objects. These elements repeat in a predictable manner. It can be a template or model which can be used to generate things or parts of a thing, especially if the things that are created have enough in common for the underlying pattern to be inferred, in which case the things are said to exhibit the unique pattern. The most basic patterns, called Tessellations, are based on repetition and periodicity. A single template, tile, or cell, is combined with duplicates without change or modification. Other patterns, such as Penrose tiling and Pongal or Kolam patterns from India, use symmetry which is a form of finite repetition, instead of translation which can repeat to infinity. Fractal patterns also use magnification or scaling giving an effect known as self-similarity or scale invariance. Some plants, like Ferns, even generate a pattern using an affine transformation which combines translation, scaling, rotation and reflection. 5


“

All the evolution we know of proceeds from the

Vague Definite�

to the

- Charles Sanders Peirce

The acorn, or oak nut, is the nut of the oaks and their close relatives. It usually contains a single seed (rarely two seeds), enclosed in a tough, leathery shell, and borne in a cup-shaped cupule.

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Acorns play an important role in forest ecology when oaks are the dominant species or are plentiful. The volume of the acorn crop may vary wildly, creating great abundance or stress on the many animals dependent on acorns and the predators of those animals. Wildlife with acorns included as an important part of their diets are birds, such as jays, pigeons, some ducks, and several species of woodpeckers. Small mammals that feed on acorns include mice, squirrels and several other rodents. Large mammals, such as pigs, bears, and deer, also consume large amounts of acorns; they may constitute up to 25% of the diet of deer in the autumn. In Spain and Portugal, pigs are still turned loose in dehesas (large oak groves) in the autumn, to fill and fatten themselves on acorns. However, acorns are toxic to some other animals, such as horses. Acorns are attractive to animals because they are large and can be efficiently consumed or cached, they are also rich in nutrients. Percentages vary from species to species, but all acorns contain large amounts of protein, carbohydrates and fats, as well as the minerals calcium, phosphorus and potassium, and the vitamin niacin. Total food energy in an acorn also varies by species, but all compare well with other wild foods and nuts. They also contain bitter tannins, the amount varying with the species. Tannins, which are plant polyphenols, interfere with an animal’s ability to metabolize protein, therefore creatures must adapt in different ways to use the nutriants acorns contain. Animals that cache acorns may wait to consume some of them until sufficient groundwater has percolated through to leach out the tannins. Other animals buffer their acorn diet with other foods. Many insects, birds, and mammals metabolize tannins with fewer ill effects than humans. Species of acorn that contain large amounts of tannins are very bitter, astringent, and potentially irritating if eaten raw. This is particularly true of the acorns of red oaks. The acorns of white oaks, being much lower in tannins, are nutty in flavor, which is enhanced if the acorns are given a light roast before grinding. Tannins can be removed by soaking chopped acorns in several changes of water, until the water no longer turns brown. Acorns are also sometimes prepared as a massage oil.

Single Seed

Fallen Acorn

Crushed Acorn

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This monograph looks at the definition of evolution in a number of forms, from the scientific to relationships to nature itself. It demonstrates the changes involved in evolution and the adaptions that have to take place


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