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1. Evolution is a scientific process of organismal change over a period of time, resulting in genetic modification; it is the development of life. Evolution cannot take place in one individual’s lifetime; rather it is a population-level process that takes place over many generations. This scientific process depends on mutations, or random changes in a species DNA sequence. Evolution is broken down into three mechanisms that drive the process of evolutionary change: Natural Selection, Genetic Drift, and Migration (Wenzel 2015). Mutations can cause differences in physical traits and is the cause of variation within a population. The mechanism of Natural Selection is a causal process that is the variation in an organism’s survival and reproduction …show more content…
An example of evolution that has taken place over the last 200 years is the Italian Wall Lizard. In 1971, ten Podarcis sicula or Italian Wall Lizards were introduced to the island of Pod Mrcau. Decades later the lizards were compared to the colony from which they were taken. It was found that their diets had changed to be one heavy in vegetation. The lizard now had a larger head, different gut structure, and has a much greater bite force (Listverse 2011). The lizards also had developed “cecal valves,” which are muscles between the large and small intestine that “slow down food digestion in fermenting chambers,” allowing their bodies “to process the vegetation 's cellulose into volatile fatty acids” (National Geographic Society 2008). In this case, the Italian Wall Lizard has evolved and adapted to its new environment within a few generations. This example of evolution within the past decades was caused by a forced migration, Natural Selection and adaptation. The ten lizards were forced into a new environment, and they eventually adapted to this environment. The lizards that were able to eat a diet of vegetation rather than meat were able to survive in this new environment heavy in vegetation, and pass on their genes to the next
Biological evolution is a change in the characteristics of living organisms over generations (Scott, 2017). A basic mechanism of evolution, the genetic drift, and mutation is natural selection. According to Darwin's theory of evolution, natural selection is a process in nature in which only the organisms best adapted to their environmental surroundings have a higher chance of surviving and transmitting their genetic characters in increasing numbers to succeeding generations while those less adapted tend to be eliminated. There has been many experimental research projects that relate to the topic of natural selection and evolution.
1. The way in which the process of learning is the result of Natural Selection is by the way we learn on how to live our life and to survive to be able to make offspring. Our book says that “those of their offspring that share their parents ' advantage will also tend to survive and reproduce” (Chance,2014). There is also the example in the book of Gregor Mendel in which he did the experiement with the peas and with natural selection he was able to have a garden full of peas. And last there is the experiment of the birds with different shapes of beak Charles Darwin said that "it is very remarkable that a nearly perfect gradation of structure in this one group can be traced in the form of the beak, from one exceeding in dimensions that of the
What is evolution? Evolution in modern terms is fairly easy to understand. Evolution is the theory that life on earth began with a single celled organism that lived more that 3.5 billion years ago that slowly evolved into many diverse creatures over time. When you break down this theory into sections you get 6 factors: evolution, gradualism, speciation, common ancestry, natural selection and nonselective mechanisms of evolutionary change.
What is evolution? Evolution is the process at which all living things that are around use today that have ancient ancestors in their background. Also, with evolution it allows for use to see how we have similarities as well as differences from all living organisms from the past to the present. By being able to see the similarities as well as differences it shows how overtime we have changed and evolved through the use of evolution. However, the use of evolution involves different mechanisms in order for it to take place.
The Galapagos Islands, located about 600 miles west of continental Ecuador, contain a rich history of settlement and exploration and represent a living example of evolution that is still relevant today. For centuries, this chain of volcanic islands has been used uniquely by various cultures based off distinct needs. What has remained the same however is the fact that island isolation has forced many animal and plant species to adapt differently from one another based off their island’s environmental conditions, creating a living model of microevolution over time. Today, these models tend to be the primary resources used by biology professors when teaching their students evolutionary topics.
What is evolution and how does it work? Evolution is the theory of how one form of life changes into another form. Evolution also is the change of a population’s inherited traits from generation to generation. Evolution helps to explain why an animal, human, and plant looks the way it does and acts the way it does; it gives an explanation of the history of life. Genes come in many varieties and the evolution helps to make it happen. Mutation, natural selection, genetic drift, and gene flow: the four forces that make the evolution work.
In order for a species to survive, its population has to evolve. Evolution is the process of gradual change driven by natural selection to improve survival. Evolution is the explanation of how life got to its current state. Before the idea of evolution, the Bible gave the explanation of how things came to be, the Theory of Creation. Charles Darwin is credited for developing the theory of evolution.
Biological evolution is defined as any genetic change in a population that is inherited over several, successive generations. (R.Bailey, 2014) The changes accumulate and over time a new species is created. One of the basic mechanisms of evolution is Natural Selection. Natural Selection is random genetic variation occurring within an organisms DNA and the beneficial mutations being preserved because they aid survival. (C.Darwin, 1859) Two notable scientists associated with the theory of evolution include Charles Darwin and Jean-Baptiste Lamarck.
According to Darwin and his theory on evolution, organisms are presented with nature’s challenge of environmental change. Those that possess the characteristics of adapting to such challenges are successful in leaving their genes behind and ensuring that their lineage will continue. It is natural selection, where nature can perform tiny to mass sporadic experiments on its organisms, and the results can be interesting from extinction to significant changes within a species.
Many scientists in the past, such as Aristotle and Plato, believed that there were no changes in populations; however, other scientists, such as Darwin and Wallace, arose and argued that species inherit heritable traits from common ancestors and environmental forces drives out certain heritable traits that makes the species better suited to survive or be more “fit” for that environment. Therefore, species do change over a period of time and they were able to support their theory by showing that evolution does occur. There were four basic mechanisms of evolution in their theory: mutation, migration, genetic drift, and natural selection. Natural selection is the gradual process by which heritable traits that makes it more likely for an organism to survive and successfully reproduce increases, whereas there is a decline in those who do have those beneficial heritable traits (Natural Selection). For example, there is a decrease in rain which causes a drought in the finches’ environment. The seeds in the finches’ environment would not be soft enough for the smaller and weaker beak finches to break; therefore, they cannot compete with the larger and stronger beak finches for food. The larger and stronger beak finches has a heritable trait that helps them survive and reproduce better than others for that particular environment which makes them categorized under natural selection (Freeman, 2002).
The evolutionary theory is the concept that species evolve over time through the mechanism of natural selection of survival and reproduction. Natural selection means acting on the assumption that various living organisms were produced by genetic diversity and mutation. The evolution theory may also be referred to as the philosophizing science. This theory states that all phenomena are derived from natural causes and can be explained by scientific laws without reference to a plan or purpose.
Throughout the various phyla discussed evolutionary advancements are relevant. Starting from the basic, simplistic life forms of a sponge, up to the intelligence of an octopus and advance organ systems of Annelida the changes have only improved. Some species changed and evolved because as populations grow, they spread out farther and different conditions begin to affect their life. Why some species haven’t changed is because their body plan and system works for the environment they inhabit. Evolution has helped animals spread out all over the world and adapt to various conditions, seen in the habitats Aschelminthes can prosper in.
Evolution is a complex process by which organisms change over time; it is a process in which traits are passed from one generation to the next (Darwin and Beer 1996:108-139). Evolutionists have tried to explain the loss of functions of different organs, for centuries. The two most prominent scientists that studied evolution were Jean-Baptist Lamarck and Charles Darwin. Lamarck’s theory of inheritance of acquired characters and Darwin’s variational evolution were the most important theories that attempted to explain evolution before the discovery of genes during the beginning of the twentieth century.
Biological evolution is the name for the changes in gene frequency in a population of a species from generation to generation. Evolution offers explanation to why species genetically change over years and the diversity of life on Earth. Although it is generally accepted by the scientific community, Charles Darwin’s theory of evolution has been studied and debated for several decades. In 1859, Darwin published On The Origin of Species, which introduced the idea of evolutionary thought which he supported with evidence of one type of evolutionary mechanism, natural selection. Some of the main mechanisms of evolution are natural selection, mutation, and genetic drift. The idea that all life on Earth shares a common ancestor has been around for a long time but has risen to significance in society over the last two centuries.
Without evolution, and the constant ever changing environment, the complexity of living organisms would not be as it is. Evolution is defined as a process that results in heritable changes in a population spread over many generations (8).Scientists believe in the theory of evolution. This belief is based on scientific evidence that corroborates the theory of evolution. In Figure 1 the pictures of the skulls depict the sequence of the evolution of Homo-sapiens. As the figure shows, man has evolved from our common ancestor that is shared by homo-sapiens. The change of diet of homo-sapiens over time has thought to contribute to the change in jaw structure and overall skull shape.