The Berkeley Evolution Site
The Berkeley site has resources that can help students and educators learn about and teach evolution. The resources are arranged into different learning paths such as "What did T. rex taste like?"
Charles Darwin's theory of natural selection explains how creatures who are better able to adapt biologically to changing environments survive longer and those that do not end up becoming extinct. This process of evolution in biology is what science is all about.
What is Evolution?
The term "evolution" can have many nonscientific meanings. For instance it could refer to "progress" and "descent with modifications." It is an academic term that refers to the process of changing characteristics in a species or species. In biological terms this change is based on natural selection and genetic drift.
Evolution is a fundamental concept in modern biology. It is an established theory that has stood the test of time and thousands of scientific studies. It does not address the existence of God or religious beliefs like other scientific theories such as the Copernican or germ theory of diseases.
Early evolutionists such as Erasmus Darwin (Charles’s grandfather) and Jean-Baptiste Lamarck believed that certain physical characteristics were predetermined to evolve in a step-like fashion over time. They referred to this as the "Ladder of Nature" or scala naturae. Charles Lyell first used this term in 1833 in his Principles of Geology.
Darwin published his theory of evolution in his book On the Origin of Species, written in the early 1800s. It states that all species of organisms share common ancestors that can be traced through fossils and other evidence. This is the current view of evolution, and is supported by a variety of research lines in science, including molecular genetics.
Scientists do not know how organisms evolved but they are sure that natural selection and genetic drift is the primary reason for the evolution of life. People with desirable traits are more likely than others to live and reproduce. These individuals pass on their genes on to the next generation. In time, this results in a gradual accumulation of changes in the gene pool, which eventually lead to new species and types.
Certain scientists use the term"evolution" in reference to large-scale changes, such the evolution of one species from an ancestral one. Some scientists, like population geneticists, define the term "evolution" in a broader sense by talking about the net variation in the frequency of alleles over generations. Both definitions are valid and acceptable, but some scientists argue that allele-frequency definitions miss important aspects of the evolution.
Origins of Life
The most important step in evolution is the appearance of life. This happens when living systems begin to evolve at the micro level, within cells, for example.
The origin of life is an important subject in many disciplines such as biology and chemistry. The origin of life is an area that is of immense interest to scientists because it is a challenge to the theory of evolution. It is often called "the mystery of life" or "abiogenesis."
Traditionally, the idea that life can arise from nonliving things is known as spontaneous generation or "spontaneous evolution." This was a popular belief prior to Louis Pasteur's research showed that it was impossible for the creation of life to occur by an entirely natural process.
Many scientists believe that it is possible to make the transition from nonliving materials to living. The conditions needed to create life are difficult to reproduce in a lab. Researchers who are interested in the origins and development of life are also keen to understand the physical properties of the early Earth as well as other planets.
The growth of life is also dependent on a series of complex chemical reactions, which cannot be predicted by the basic physical laws. These include the reading and re-reading of complex molecules, like DNA or RNA, to produce proteins that serve a specific function. These chemical reactions are often compared with the chicken-and-egg issue of how life first appeared: The appearance of DNA/RNA and protein-based cell machinery is essential for the onset of life, but without the emergence of life, the chemistry that makes it possible isn't working.
Abiogenesis research requires collaboration among scientists from different fields. This includes prebiotic chemists astrobiologists, planetary scientists geophysicists and geologists.
Evolutionary Changes
The term "evolution" today is used to describe gradual changes in genetic traits over time. These changes may be the result of the adaptation to environmental pressures as explained in Darwinism.
This is a process that increases the frequency of those genes that confer an advantage in survival over other species, resulting in gradual changes in the overall appearance of a population. These evolutionary changes are triggered by mutations, reshuffling of genes during sexual reproduction, and the flow of genes.
While mutation and reshuffling of genes occur in all living organisms, the process by which beneficial mutations are more prevalent is known as natural selection. This happens because, as mentioned above, those individuals with the beneficial trait tend to have a higher reproductive rate than those without it. This difference in the number of offspring produced over many generations can cause a gradual change in the number of advantageous characteristics in the group.
This can be seen in the evolution of various beak designs on finches that are found in the Galapagos Islands. They have created these beaks to ensure they can get food more easily in their new habitat. These changes in shape and form can also aid in the creation of new species.
The majority of the changes that occur are caused by one mutation, but occasionally, multiple mutations occur at the same time. The majority of these changes are not harmful or even harmful to the organism, but a small percentage can be beneficial to the longevity and reproduction of the species, thus increasing the frequency of these changes in the population over time. 에볼루션코리아 is a mechanism that can produce the accumulating changes over time that lead to the creation of a new species.
Many people confuse evolution with the idea of soft inheritance, which is the idea that inherited traits can be altered by deliberate choice or misuse. This is a misunderstanding of the nature of evolution and of the actual biological processes that cause it. A more precise description is that evolution involves a two-step process, which involves the separate and often conflicting forces of natural selection and mutation.
Origins of Humans
Humans of today (Homo sapiens) evolved from primates - a group of mammals that includes chimpanzees, gorillas, and bonobos. Our predecessors walked on two legs, as shown by the oldest fossils. Genetic and biological similarities suggest that we share an intimate relationship with Chimpanzees. In reality we are the closest related to the chimpanzees within the Pan genus which includes bonobos and pygmy chimpanzees. The last common ancestor between modern humans and chimpanzees dated between 8 and 6 million years old.
Humans have evolved a variety of characteristics over time including bipedalism, the use of fire, and the development of advanced tools. It is only in the past 100,000 years or so that most of the essential characteristics that differentiate us from other species have been developed. They include a huge, complex brain, the ability of humans to create and use tools, and cultural variety.
Evolution is when genetic changes allow members of the group to better adapt to their environment. Natural selection is the mechanism that triggers this adaptation. Certain characteristics are more desirable than others. The ones who are better adapted are more likely to pass their genes on to the next generation. This is the way all species evolve and is the basis of the theory of evolution.
Scientists refer to this as the "law of natural selection." The law states species that share an ancestor will tend to develop similar characteristics in the course of time. This is because these traits make it easier to live and reproduce in their environment.
All organisms possess the DNA molecule, which contains the information needed to guide their growth. The DNA molecule consists of base pairs that are arranged in a spiral around phosphate molecules and sugar molecules. The sequence of bases within each strand determines phenotype which is the person's distinctive appearance and behavior. Variations in a population can be caused by mutations and reshufflings of genetic material (known collectively as alleles).
Fossils from the earliest human species Homo erectus and Homo neanderthalensis have been discovered in Africa, Asia and Europe. These fossils, despite a few differences in their appearance all support the hypothesis that modern humans' ancestors originated in Africa. The genetic and fossil evidence suggests that the first humans left Africa and moved to Asia and Europe.