The Berkeley Evolution Site<br /><br />Teachers and students who browse the Berkeley site will find resources to assist them in understanding and teaching evolution. The materials are organized into a variety of learning paths, such as "What did T. rex taste like?"<br /><br />Charles Darwin's theory of natural selection states that over time creatures that are more able to adapt to changing environments thrive, and those that don't become extinct. This process of biological evolution is the basis of science.<br /><br />What is Evolution?<br /><br />The term "evolution" has a variety of nonscientific meanings. For instance "progress" or "descent with modification." Scientifically it is a term used to describe a changing the characteristics of organisms (or species) over time. The reason for this change is biological terms on natural drift and selection.<br /><br />Evolution is a fundamental principle in the field of biology today. It is a concept that has been proven by a myriad of scientific tests. Contrary to other theories of science like the Copernican theory or the germ theory of disease, the evolution theory is not a discussion of religion or God's existence.<br /><br />Early evolutionists such as Erasmus Darwin (Charles’s grandfather) and Jean-Baptiste Lamarck believed that certain physical characteristics were predetermined to change in a gradual manner over time. This was known as 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.<br /><br />In the early 1800s, Darwin formulated his theory of evolution and published it in his book On the Origin of Species. It asserts that all species of organisms have common ancestors that can be traced using fossils and other evidence. This is the current view of evolution, which is supported by numerous lines of research in science, including molecular genetics.<br /><br />While scientists do not know exactly how organisms evolved however they are sure that the evolution of life on earth is the result of natural selection and genetic drift. People with advantages are more likely to survive and reproduce. These individuals transmit their genes to the next generation. Over time this leads to an accumulation of changes to the gene pool, which eventually lead to new species and types.<br /><br />Some scientists use the term"evolution" to refer to large-scale changes, like the evolution of a species from an ancestral one. Certain scientists, such as population geneticists, define the term "evolution" in a broader sense by using the term "net change" to refer to the change in the frequency of alleles across generations. Both definitions are correct and palatable, but some scientists argue that allele-frequency definitions do not include important aspects of evolution.<br /><br />Origins of Life<br /><br />The birth of life is a key stage in evolution. The beginning of life takes place when living systems begin to develop at a microscopic scale, for instance within individual cells.<br /><br />The origins of life are an issue in a variety of disciplines that include biology, chemistry, and geology. The question of how living organisms began is a major topic in science due to it being an enormous challenge to the theory of evolution. It is often called "the mystery of life," or "abiogenesis."<br /><br />Traditionally, the notion that life can emerge from nonliving things is called spontaneous generation, or "spontaneous evolution." <a href="https://evolutionkr.kr/">에볼루션 블랙잭 Evolution</a> was a popular belief prior to Louis Pasteur's research showed that it was impossible for the development of life to happen through the natural process.<br /><br />Many scientists believe it is possible to move from living to nonliving substances. However, the conditions needed are extremely difficult to replicate in the laboratory. This is why scientists investigating the nature of life are also interested in determining the physical properties of early Earth and other planets.<br /><br />The growth of life is dependent on a number of complex chemical reactions, which cannot be predicted by simple physical laws. These include the reading of long, information-rich molecules (DNA or RNA) into proteins that carry out a function and the replication of these intricate molecules to generate new DNA or sequences of RNA. These chemical reactions can be compared to the chicken-and-egg problem which is the development and emergence of DNA/RNA, protein-based cell machinery, is required for the beginning of life. But without life, the chemistry required to make it possible does appear to work.<br /><br />Abiogenesis research requires collaboration between scientists from various fields. This includes prebiotic chemists the astrobiologists, the planet scientists geophysicists, geologists, and geophysicists.<br /><br />Evolutionary Changes<br /><br />The word evolution is usually used today to describe the cumulative changes in the genetic characteristics of populations over time. These changes may be the result of the adaptation to environmental pressures as explained in Darwinism.<br /><br />This is a process that increases the frequency of those genes in a species which confer an advantage in survival over others which results in gradual changes in the overall appearance of a group. The specific mechanisms behind these evolutionary changes include mutation and reshuffling of genes in sexual reproduction, and gene flow between populations.<br /><br />Natural selection is the process that allows beneficial mutations to become more common. All organisms undergo changes and reshuffles of genes. As previously mentioned, those who possess the desirable trait have a higher reproductive rate than those that do not. This differential in the number of offspring that are produced over many generations can result in a gradual shift in the number of advantageous characteristics in the group.<br /><br />This is evident in the evolution of various beak shapes on finches from the Galapagos Islands. They have developed these beaks so they can get food more easily in their new environment. These changes in the shape and appearance of organisms could also be a catalyst for the creation of new species.<br /><br />Most of the changes that take place are caused by a single mutation, but occasionally, multiple mutations occur at the same time. The majority of these changes could be neutral or even harmful however, a small percentage may have a positive effect on the survival of the species and reproduce, increasing their frequency over time. Natural selection is a mechanism that can produce the accumulating changes over time that lead to a new species.<br /><br />Many people confuse evolution with the idea of soft inheritance that is the belief that traits inherited from parents can be changed through conscious choice or abuse. This is a misinterpretation of the nature of evolution, and of the actual biological processes that cause it. A more precise description is that evolution is a two-step process that involves the distinct and often antagonistic forces of mutation and natural selection.<br /><br />Origins of Humans<br /><br /><br /><br />Modern humans (Homo sapiens) evolved from primates - a species of mammals that also includes chimpanzees and gorillas and bonobos. The earliest human fossils indicate that our ancestors were bipeds. They were walkers on two legs. Genetic and biological similarities show that we share a close relationship with the chimpanzees. In fact, we are most closely connected to chimpanzees belonging to the Pan genus which includes pygmy chimpanzees and bonobos. The last common ancestor of humans and chimpanzees was between 8 and 6 million years old.<br /><br />As time has passed humans have developed a range of characteristics, including bipedalism as well as the use of fire. They also developed advanced tools. However, it is only in the past 100,000 years or so that most of the important traits that distinguish us from other species have developed. They include a huge, complex brain human ability to create and use tools, and cultural variety.<br /><br />Evolution occurs when genetic changes allow individuals of a population to better adapt to their environment. This adaptation is driven by natural selection, a process whereby certain traits are preferred over others. People with better adaptations are more likely to pass on their genes to the next generation. This is how all species evolve and the basis for the theory of evolution.<br /><br />Scientists call this the "law of natural selection." The law states that species that have a common ancestor are likely to acquire similar traits in the course of time. This is because the characteristics make it easier for them to live and reproduce in their natural environment.<br /><br />All organisms have a DNA molecule, which contains the information needed to guide their growth and development. The DNA structure is made of base pairs that are arranged in a spiral around sugar and phosphate molecules. The sequence of bases in each strand determines the phenotype, the appearance and behavior of an individual. A variety of mutations and reshufflings of the genetic material (known as alleles) during sexual reproduction can cause variation in a population.<br /><br />Fossils from the first human species, Homo erectus, as well as Homo neanderthalensis have been found in Africa, Asia and Europe. These fossils, despite a few variations in their appearance, all support the theory that modern humans' ancestors originated in Africa. The evidence from fossils and genetics suggests that early humans left Africa and moved to Asia and Europe.<br /><br />