The Berkeley Evolution Site
The Berkeley site has resources that can help students and educators to understand and teach about evolution. The resources are organized into optional learning paths like "What did T. rex taste like?"
Charles Darwin's theory on natural selection explains how creatures who are better equipped to adapt biologically to changing environment survive over time and those that do not become extinct. This process of evolution in biology is what science is all about.
What is Evolution?
The term "evolution" can have many nonscientific meanings, including "progress" or "descent with modification." Scientifically it refers to a changes in the traits of living things (or species) over time. In terms of biology this change is caused by natural selection and genetic drift.
Evolution is an important tenet in modern biology. It is a concept that has been tested and proven by thousands of scientific tests. It does not address spiritual beliefs or God's presence like other theories in science, like 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 stepped-like 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.
Darwin revealed his theory of evolution in his book On the Origin of Species which was written in the early 1800s. It asserts that different species of organisms have a common ancestry, which can be proven through fossils and other evidence. This is the modern view of evolution that is supported by numerous lines of research in science which includes molecular genetics.
Scientists do not know how organisms evolved but they are sure that natural selection and genetic drift is the reason for the evolution of life. People with traits that are advantageous are more likely to survive and reproduce, and they pass their genes on to the next generation. Over time, this results in an accumulation of changes to the gene pool that gradually lead to new species and forms.
Some scientists use the term"evolution" in reference to large-scale changes, such the evolution of a species from an ancestral one. Other scientists, such as population geneticists, define the term "evolution" more broadly, referring to an overall change in allele frequencies over generations. Both definitions are valid and reliable however some scientists believe that the definition of allele frequency is lacking essential aspects of the evolution process.
Origins of Life
One of the most crucial steps in evolution is the emergence of life. This happens when living systems begin to evolve at the micro level, within cells, for instance.
The origins of life are an important subject in many fields such as biology and chemical. The question of how living things got their start is of particular importance in science because it is an important challenge to the theory of evolution. It is often called "the mystery of life," or "abiogenesis."
The idea that life could be born from non-living things was called "spontaneous generation" or "spontaneous evolutionary". It was a popular belief before Louis Pasteur's tests showed that the development of living organisms was not achievable through the natural process.
Many scientists still think it is possible to move from living to nonliving substances. The conditions required for the creation of life are difficult to replicate in a laboratory. Researchers interested in the evolution and origins of life are also eager to understand the physical properties of the early Earth as well as other planets.
The growth of life is dependent on a number of complex chemical reactions that are not predicted by the basic physical laws. These include the reading of long information-rich molecules (DNA or RNA) into proteins that carry out functions as well as the replication of these complex molecules to create new DNA or sequences of RNA. These chemical reactions are often compared with the chicken-and-egg issue of how life began with the emergence of DNA/RNA and proteins-based cell machinery is vital to the birth of life, however, without the appearance of life the chemical process that allows it isn't working.
Abiogenesis research requires collaboration among scientists from various disciplines. This includes prebiotic chemists planet scientists, astrobiologists geophysicists and geologists.
에볼루션 카지노 is usually used to describe the accumulated changes in genetic characteristics of an entire population over time. These changes could be the result of the adaptation to environmental pressures as explained in Darwinism.
This is a method that increases the frequency of genes in a species that confer a survival advantage over others and causes gradual changes in the appearance of a group. The specific mechanisms behind these evolutionary changes are mutation or reshuffling genes during sexual reproduction, as well as gene flow between populations.
Natural selection is the process that makes beneficial mutations more common. All organisms undergo mutations and reshuffles in their genes. As noted above, individuals with the beneficial trait have a higher reproductive rate than those who do not. This differential in the number of offspring that are produced over a long period of time can result in a gradual change in the average number advantageous characteristics in a group.
An excellent example is the growing beak size on various species of finches on the Galapagos Islands, which have developed beaks with different shapes that allow them to easily access food in their new environment. These changes in the form and shape of living organisms may also be a catalyst for the creation of new species.
Most of the changes that take place are the result of one mutation, however sometimes, several changes occur simultaneously. The majority of these changes are neither harmful nor even harmful to the organism however a small portion of them could have a positive impact on the survival of the organism and its reproduction, thereby increasing the frequency of these changes in the population over time. This is the way of natural selection, and it could be a time-consuming process that produces the gradual changes that eventually lead to a new species.
Some people mistakenly associate evolution with the concept of soft inheritance, which is the idea that inherited traits can be altered by conscious choice or by abuse. This is a misunderstanding of the biological processes that lead to evolution. A more accurate description is that evolution involves a two-step process, that involves the distinct, and often competing, forces of mutation and natural selection.
Origins of Humans
Humans of today (Homo Sapiens) evolved from primates, a group of mammal species that includes chimpanzees and gorillas. The earliest human fossils prove that our ancestors were bipeds - walking on two legs. Genetic and biological similarities suggest that we share an intimate relationship with Chimpanzees. In actual fact, our closest relatives are the chimpanzees from the Pan genus. This includes pygmy and bonobos. The last common human ancestor and chimpanzees lived between 8 and 6 million years ago.
In the course of time, humans have developed a range of characteristics, such as bipedalism as well as the use of fire. They also developed advanced tools. It is only in the past 100,000 years or so that the majority of the important traits that distinguish us from other species have been developed. They include a huge brain that is sophisticated human ability to construct and use tools, and the diversity of our culture.
Evolution occurs when genetic changes allow individuals in a group to better adapt to their surroundings. Natural selection is the mechanism that drives this change. Certain traits are preferred over others. The more adjusted are more likely to pass on their genes to the next generation. This is the way all species evolve and the basis of the theory of evolution.
Scientists refer to it as the "law of natural selection." The law says that species that have a common ancestor are more likely to develop similar traits over time. It is because these traits make it easier to reproduce and survive within their environment.
All organisms have DNA molecules, which contains the information needed to direct their growth and development. The structure of DNA is made of base pairs that are arranged in a spiral around phosphate and sugar molecules. The sequence of bases within each strand determines the phenotype, or the individual's characteristic appearance and behavior. A variety of changes and reshuffling of genetic material (known as alleles) during sexual reproduction cause variation in a group.
Fossils from the first human species, Homo erectus, and Homo neanderthalensis have been found in Africa, Asia and Europe. These fossils, despite a few variations in their appearance, all support the theory of the origins of modern humans in Africa. Evidence from fossils and genetics suggest that early humans came from Africa into Asia and then Europe.