Darwin's Theory

Background

The Theory of Evolution Evolutionary concepts appeared in some early Greek writings, e.g., in the works of Thales, Empedocles, Anaximander, and Aristotle. Under the restraining influence of the Church, no evolutionary theories developed during some 15 centuries of the Christian era to challenge the belief in special creation and the literal interpretation of the first part of Genesis; however, much data was accumulated that was to be utilized by later theorists. With the growth of scientific observation and experimentation, there began to appear from about the middle of the 16th cent. glimpses of the theory of evolution that emerged in the mid 19th cent. The invention of the microscope, making possible the study of reproductive cells and the growth of the science of embryology, was a factor in overthrowing hampering theories founded in false ideas of the reproductive process; studies in classification and anatomy, based on dissection, were also influential.In 1859 appeared the first edition of Darwin's Origin of Species. The influence of this evolutionary theory upon scientific thought and experimentation cannot be overestimated. In the years following the promulgation of Darwin's theory of evolution, many accepted and many denied its validity.The theory found an opposing force in some religious creeds that declared it incompatible with their basic tenets. For a time evolution, sometimes falsely interpreted as meaning human descent from monkeys rather than descent from an ancient and extinct ancestor, became a target for attack by both church and educational authorities. Feeling ran high even as late as the time of the Scopes trial.Nevertheless, the theory of evolution became firmly entrenched as a scientific principle, and in most creeds it has been reconciled with religious teachings. Some Christian fundamentalists, however, do not accept the theory and have striven to have biblical creationism taught in the schools as an alternative theory.

Source: The Theory of Evolution by John Maynard Smith Published by Cambridge University Press, 1993

Examples

Garrett Shaw Lucy(Australopithecus afarensis) Lucy is a skeleton of a Australopithecus afarensis, a species which has a combination of ape and human-like traits and characteristics. Lucy was found in Hadar, Ethiopia and is thought to be around 3.2 million years old. Lucy supports Darwin's theory of evolution because she is part of a species which is halfway between human and ape, and there are many more slightly different species which slowly start to gain more human traits, Lucy simply got the ball rolling!

Lindsey Hill The Evolution of the Giraffe

Giraffes have changed over time because of the pure need to change.As has been explained by Charles Darwin's Theory of Evolution, animals and people have changed over time because of what we explain as "survival of the fittest". Early giraffes had shorter necks, and they had to reach to get to the food that they found. Due to the torsion that put on their necks, as giraffes mated and had offspring, their offspring's necks got longer and longer. As these giraffes that had longer necks ate all of the leaves that they could reach, they had the same problem their ancestors had, so they kept stretching their necks to reach the uneaten leaves, and as that precess continued through time, the giraffe's neck got progressively longer to the point that they had to bend down to drink water like they do now, because their necks are too long. Whenever people say "Did you know that giraffes have the same number of vertebra in their necks as we do?" it is able to be explained easily. At the beginning, giraffes had short necks, and they had to reach for their food, so their necks got remarkably longer because of their ancestors stretching theirs out, then mating and so on and so forth. Keep that in mind for your next visit to the zoo!

Sean Paul Gras The Mutations of the Whale In 1994 when paleontologists found the remains of an animal called the swimming walking whale or Ambulocetus natans for its Latin name, they realized that their theories in how whales lived first on land and then mutated or evolved were true. This animal had fingers and small hooves for its front legs and the back legs were huge compared to the actual size of the "whale" although the swimming-walking whale was primarily for swimming with its hind legs it was also capable of walking on land. By doing all the tests that paleontologists do they realized that it moved by pushing with its hind legs and sweeping its tail back and forth in the water. Although whales do not have legs they have a thicker tail which is used in a similar fashion allowing them to propel themselves. The theory of how the Ambulocetes natans became a whale kind of goes like this. First the whales have a random mutation that makes their nostrils a bit higher than other whale's nostrils, this in turn makes it easier for this animal to live in water. After that random mutation that whale mates makes better offspring for the ocean life and as they get better and better at living in the ocean they begin to have other mutations such as the back legs disappearing and the front legs becoming flippers and so on and so forth. And that is how whales became how they are today, the random workings of Mother Nature.

Lucas Tyler Charles Darwin's theory states that complex beings survive by developing and keeping beneficial mutations to their DNA. This is known as natural selection, or "survival of the fittest." An example of so-called "fitter" beings in human history can be seen during the period of European exploration in the Americas. This also correlates with Turner's theory that certain geographical areas give people advantages and disadvantages. Civilizations in Europe were able to evolve past the Iron Age, and develop more complex weapons than civilizations in other places, due to the available materials. This allowed these civilizations to evolve past Aztec and Mayan Civilization. The "fitter" beings, or Spaniards, were forced to expand out of the Spanish Colony in Cuba due to overpopulation. This forced Diego Velásquez to send an exploration team onto the mainland. This team was led by Hernán Cortés. Hernán Cortés developed another goal: to conquer Mexico. Hernán Cortés used his much more advanced weaponry and allies in the Mexican area to besiege the Aztec Capital, after massacring their populace. This gave Spain a much larger overseas empire, and gave Hernán Cortés riches, fame, and a title of nobility. The Spanish conquest of the large and relatively advanced Aztec Empire is just one of the many examples of how one society has developed faster than another and wiped the other society of the map. While this theory does make sense, it can not be over interpreted. This leads to the belief that one race is "fitter" than another, and can create inequality and racism.

Example

Charles Sampson

One good example of Darwin's idea about survival of the fittest and natural selection is the evolution of finches, in specific their beaks. This shows a good example of natural selection because all of the finches evolved to be better at one thing or another. For example, finches that live off of a diet of bugs evolved long skinny beaks so that they can dig deep into the ground. This supports natural selection because most finches used to eat seeds but the ones that didn't have thick beaks to crush the seeds had to adapt and be able to eat something other than seeds, such as grubs. Once again, finches that now feed off of tree fruit kept the same thick beak but they evolved a curved point at the end so that they could pick the fruits off of trees. Finches are one of many great examples of Darwin's theories, "Natural Selection" and "Survival of the Fittest"

Example Peter Nikonowicz

An example in which Darwin's theory takes place can involve humans a lot. In the Middle East when groups of people began to farm, they planted only the biggest and most healthy wheat. Slowly but surely the wheat began to lose its old characteristics that it needed to survive in the wild. Eventually they all lost those characteristics because humans contribute to natural selection too. Today Clementines or Cuties are a type of citrus fruit that were genetically designed to be seedless, juicy, flavorful, easy to peal, and small. It started the same way as the tribe in the middle east grew their wheat and grains. Through science and technology scientists today can take DNA strands from good fruit to make a super seed that will become a companies product. Because these plants do not need protection from the wild, they will lose most of their traits that did matter when they were in the wild. If you tried to grow wheat or Cuties today in the wild they would never make it because they have lost their protective traits through natural selection.

Claire Crane There are many examples that prove Darwin's theory, such as humans, rat snakes, finches, lizards, and many other organisms. In 1869, Charles book "The Origin of Species" was published. This book was about evolution and natural selection, a theory that stated survival of the fittest. An example of evolution is the whale and it's blowhole. Random mutations appeared in a few whales having its nostrils further back on its head. These few would have been better off living in the water than on land. The animals that were fortunate with this mutation had more offspring, and those were successful also. In following generations, the nostrils moved even farther down the head. As the "land whales" began to swim more often, their front legs turned in to flippers and their back legs grew smaller and smaller until they disappeared. Their bodies developed tail flukes to help move them through the water. There was some confusion and disbelief on this theory, until 1994 when the Ambulocetus natans was discovered. It had legs and arms that could adapt to water and land, and it had similar features to the whale. This is example really helps Darwin's theory because it shows how a land mammal can become a marine animal in a long period of time. Source: http://www.livescience.com/474-controversy-evolution-works.html

Eli Desjardins: Galapagos Islands The intriguing scientific discovery of the Galapagos finches helped Darwin construct his theory of evolution. Darwin observed that each Finch had different characteristics of their beak based on the environment they lived in. For example, thin long beaks evolved for killing other animals, like grasshoppers or mosquitoes. By contrast, those finches with short beaks on the same island died at a higher rate and could not adapt easily.. Thus, Darwin asked the question, why are thin long beak birds surviving better than those without? After researching, Darwin concluded by explaining that life was “survival of the fittest”. After this, He gave way to an important scientific and historical theory.

Amanda Feldman "Natural Selection of Moths"

One of the many examples of Charles Darwin's idea of natural selection is with the "peppered moths" near English industrial cities. During the 19th century, air pollution became so high that it killed the lichen off trees and blackened the bark. When the moths landed on the bark, the darker ones were harder to spot by birds and other predators, making them have a higher survival rate, and allowing them to reproduce. As a result, the environment favored darker colored moths, and the darker moths' population crew. By 1895, 98% of the moths were almost entirely black; however, since the 1950s, air pollution control has greatly reduced the amount of air pollutants reaching the trees. This has caused the lichen to grow back, making the trees a lighter color. Now, the cycle has reversed and the lighter colored moths are favored over the dark ones. This example supports Darwin's theory of survival of the fittest because it shows that the "fittest animals", the ones best equipped to survive in a region, in this case the darker moths, are going to be the ones that survive and carry on their species. Source http://anthro.palomar.edu/evolve/evolve_2.htm