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The Berkeley Evolution Site Students and teachers who explore the Berkeley site will find a wealth of resources to help them understand and teach evolution. The materials are arranged into different learning paths such as “What did T. rex taste like?” Charles Darwin's theory on natural selection explains how animals that are better equipped to adapt to changes in their environment survive over time and those who do not end up becoming extinct. Science is concerned with the process of biological evolution. What is Evolution? The term “evolution” has a variety of nonscientific meanings. For instance “progress” or “descent with modification.” It is an academic term that is used to describe the process of changing characteristics in a species or species. The reason for this change is biological terms on natural drift and selection. Evolution is one of the fundamental tenets of modern biology. It is a concept that has been tested and proven through thousands of scientific tests. Evolution doesn't deal with spiritual beliefs or God's presence in the same way as other scientific theories such as the Copernican or germ theory of diseases. Early evolutionists, like Jean-Baptiste Lamarck and Erasmus Darwin (Charles's grandfather) believed that certain physical characteristics were predetermined to change in a gradual manner, as time passes. This was called the “Ladder of Nature”, or scala Naturae. Charles Lyell used the term to describe this idea in his Principles of Geology, first published in 1833. In the early 1800s, Darwin formulated his theory of evolution and published it in his book On the Origin of Species. It states that all species of organisms share a common ancestry which can be traced through fossils and other evidence. This is the current view on evolution, which is supported in many scientific fields that include molecular biology. While scientists don't know exactly how organisms evolved but they are certain that the evolution of life on earth is the result of natural selection and genetic drift. Individuals with advantageous traits are more likely to survive and reproduce, and these individuals transmit their genes to the next generation. As time passes the gene pool gradually changes and evolves into new species. Some scientists employ the term”evolution” to refer to large-scale change, such as the development of an animal from an ancestral one. Certain scientists, such as population geneticists define evolution in a more broad sense by referring to the net variation in the frequency of alleles over generations. Both definitions are acceptable and precise, although some scientists argue that the definition of allele frequency is lacking crucial aspects of the evolutionary process. Origins of Life The most important step in evolution is the appearance of life. The beginning of life takes place when living systems start to develop at a micro level, such as within individual cells. The origins of life is one of the major topics in various disciplines that include biology, chemistry and geology. The origin of life is an area of great interest in science, as it challenges the theory of evolution. It is often described as “the mystery of life,” or “abiogenesis.” The notion that life could be born from non-living matter was known as “spontaneous generation” or “spontaneous evolutionary”. This was a popular belief before Louis Pasteur's experiments proved that the emergence of living organisms was not achievable through the natural process. Many scientists still believe it is possible to go from nonliving materials to living. However, the conditions required are extremely difficult to replicate in a laboratory. This is why scientists investigating the beginnings of life are also interested in determining the physical properties of the early Earth and other planets. In addition, the development of life is the sequence of extremely complex chemical reactions that cannot be predicted based on basic physical laws alone. This includes the conversion of long, information-rich molecules (DNA or RNA) into proteins that carry out a function as well as the replication of these complex molecules to generate new DNA or sequences of RNA. These chemical reactions can be compared to the chicken-and-egg issue which is the development and emergence of DNA/RNA, a protein-based cell machinery, is required to begin the process of becoming a living organism. Although without life, the chemistry required to make it possible appears to be working. Research in the area of abiogenesis requires cooperation among scientists from a variety of disciplines. This includes prebiotic scientists, astrobiologists, and planetary scientists. Evolutionary Changes The word evolution is usually used today to describe the cumulative changes in the genetic traits of a population over time. These changes may result from adaptation to environmental pressures as described in the entry on Darwinism (see the entry on Charles Darwin for background) or natural selection. This process increases the frequency of genes that provide a survival advantage in an animal, resulting in an overall change in the appearance of the group. These evolutionary changes are triggered by mutations, reshuffling of genes during sexual reproduction and the flow of genes. While mutation and reshuffling of genes are common in all organisms The process through which beneficial mutations are more frequent is known as natural selection. As noted above, individuals who have the advantageous characteristic have a higher reproduction rate than those that do not. This differential in the number of offspring born over a number of generations could result in a gradual change in the number of advantageous traits within the group. This is evident in the evolution of different beak shapes on finches from the Galapagos Islands. They have developed these beaks in order that they can access food more easily in their new habitat. These changes in shape and form could also aid in the creation of new species. The majority of changes are caused by a single mutation, however sometimes multiple occur simultaneously. Most of these changes can be harmful or neutral however, a few can have a beneficial impact on survival and reproduction and increase their frequency as time passes. Natural selection is a process that causes the accumulating changes over time that lead to a new species. Some people mistakenly associate evolution with the concept of soft inheritance, which is the idea that traits inherited from parents can be changed through deliberate choice or misuse. This is a misunderstanding of the biological processes that lead to the process of evolution. It is more precise to say that evolution is a two-step independent process that involves the forces of natural selection as well as mutation. Origins of Humans Humans of today (Homo sapiens) evolved from primates – a group of mammals that also includes chimpanzees, gorillas, and bonobos. Our predecessors walked on two legs, as evidenced by the oldest fossils. Genetic and biological similarities show that we share the same ancestry with the chimpanzees. In reality we are the closest connected to chimpanzees belonging to the Pan genus that includes pygmy and bonobos and pygmy-chimpanzees. The last common human ancestor as well as chimpanzees was between 8 and 6 million years ago. Our Site have developed a range of traits over time such as bipedalism, use of fire and advanced tools. It's only within the last 100,000 years that we have developed the majority of our key characteristics. These include a large brain that is sophisticated human ability to construct and use tools, and cultural variety. Evolution is when genetic changes allow members of an organization to better adapt to the environment. Natural selection is the process that drives this change. Certain characteristics are more desirable than others. The more adaptable are more likely to pass on their genes to the next generation. This is the process that evolves all species, and it is the basis of the theory of evolution. Scientists call this the “law of natural selection.” The law states species that have an ancestor in common will tend to develop similar characteristics in the course of time. This is because those characteristics make it easier for them to live and reproduce in their environments. Every living thing has a DNA molecule that contains the information needed to guide their growth. The DNA molecule is made up of base pairs arranged spirally around sugar molecules and phosphate molecules. The sequence of bases within each strand determines the phenotype, or the individual's characteristic appearance and behavior. The variations in a population are caused by mutations and reshufflings in genetic material (known collectively as alleles). Fossils from the first human species, Homo erectus, and Homo neanderthalensis have been found in Africa, Asia and Europe. Despite some differences, these fossils all support the hypothesis that modern humans first came into existence in Africa. Evidence from fossils and genetics suggest that early humans came out of Africa into Asia and then Europe.