Is Evolution Site As Important As Everyone Says?
The Berkeley Evolution Site
The Berkeley site has resources that can assist students and teachers understand and teach evolution. The materials are arranged in optional learning paths, such as "What does T. rex look like?"
Charles Darwin's theory of natural selection explains how over time, animals that are better able to adapt biologically to changing environments survive and those that don't become extinct. Science is concerned with this process of evolutionary change.
What is Evolution?
The term "evolution" has a variety of nonscientific meanings, such as "progress" or "descent with modification." It is scientifically based and refers to the process of change of characteristics over time in organisms or species. The reason for this change is biological terms on natural drift and selection.
Evolution is a central tenet of modern biology. It is a concept that has been tested and verified by a myriad of scientific tests. Evolution does not deal with spiritual beliefs or God's presence, unlike many other theories of science, such as the Copernican or germ theory of disease.
Early evolutionists, such as Jean-Baptiste Lamarck and Erasmus Darwin (Charles's grandfather), believed that certain physical characteristics were predetermined to change in a step-like way, 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.
In the early 1800s, Darwin formulated his theory of evolution and published it in his book On the Origin of Species. It claims that different species of organisms share the same ancestry, which can be determined through fossils and other lines of evidence. This is the modern view of evolution, and is supported by a variety of lines of scientific research which includes molecular genetics.
While scientists do not know exactly how organisms developed, they are confident that the evolution of life on earth is a result of natural selection and genetic drift. Individuals with advantageous characteristics are more likely than others to survive and reproduce. These individuals pass on their genes to the next generation. Over time this leads to an accumulation of changes in the gene pool, which eventually result in new species and types.
Certain scientists use the term"evolution" in reference to large-scale changes, such the development of an animal from an ancestral one. Some scientists, like population geneticists, define the term "evolution" in a broader sense by talking about the net change in the frequency of alleles across generations. Both definitions are acceptable and accurate however, some scientists claim that the allele-frequency definition omits important features of the evolutionary process.
Origins of Life
One of the most crucial steps in evolution is the appearance of life. This happens when living systems begin to develop at the micro level - within individual cells, for instance.
The origins of life is an issue in a variety of disciplines such as biology, chemistry, and geology. The question of how living things started is a major topic in science because it is a major challenge to the theory of evolution. It is sometimes referred to as "the mystery" of life or "abiogenesis."
The idea that life could arise from non-living things was called "spontaneous generation" or "spontaneous evolutionary". It was a popular belief prior to Louis Pasteur's tests showed that the development of living organisms was not possible by the natural process.
Many scientists still believe that it is possible to go from nonliving substances to life. The conditions needed for the creation of life are difficult to reproduce in a lab. Researchers who are interested in the origins and development of life are also eager to learn about the physical characteristics of the early Earth as well as other planets.
Furthermore, the growth of life is dependent on an intricate sequence of chemical reactions that cannot be predicted from the fundamental physical laws alone. These include the transformation of long information-rich molecules (DNA or RNA) into proteins that perform a function as well as the replication of these intricate molecules to produce new DNA or RNA sequences. These chemical reactions can be compared to a chicken-and egg problem that is the emergence and growth of DNA/RNA, a protein-based cell machinery, is essential to begin the process of becoming a living organism. But without life, the chemistry that is required to enable it is working.
Abiogenesis research requires collaboration with scientists from various fields. This includes prebiotic scientists, astrobiologists, and planetary scientists.
Evolutionary Changes
The term "evolution" is typically used to describe the accumulated changes in the genetic traits of populations over time. These changes could result from adaptation to environmental pressures as explained in the article on Darwinism (see the entry on Charles Darwin for background) or natural selection.
discover here increases the frequency of genes that confer the advantage of survival for the species, leading to an overall change in the appearance of the group. These evolutionary changes are triggered by mutations, reshuffling genes in the process of sexual reproduction, and also by gene flow.
Natural selection is the process that makes beneficial mutations more common. All organisms undergo mutations and reshuffles in their genes. This occurs because, as mentioned above those with the beneficial trait tend to have a higher fertility rate than those without it. This difference in the number of offspring produced over a long period of time can result in a gradual change in the number of advantageous traits within a group.
This is evident in the evolution of different beak designs on finches that are found in the Galapagos Islands. They have developed these beaks so they can get food more quickly in their new home. These changes in form and shape can also help create new organisms.
Most of the changes that occur are caused by a single mutation, but sometimes, several changes occur at once. The majority of these changes are neither harmful nor even harmful to the organism however a small portion of them could be beneficial to the longevity and reproduction of the species, thus increasing their frequency in the population over time. Natural selection is a process that can produce the accumulating change over time that leads to a new species.
Some people confuse the notion of evolution with the notion that traits inherited can be changed through conscious choice or by use and abuse, which is known as soft inheritance. This is a misinterpretation of the biological processes that lead to the process of evolution. It is more accurate to say that evolution is a two-step, independent process, which involves the forces of natural selection as well as mutation.
Origins of Humans
Modern humans (Homo Sapiens) evolved from primates, a group of mammal species that includes gorillas and chimpanzees. The earliest human fossils prove that our ancestors were bipeds, walkers on two legs. Genetic and biological similarities suggest that we share the same ancestry with the chimpanzees. In reality our closest relatives are 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.
Humans have evolved a variety of traits throughout time such as bipedalism, 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 traits that distinguish us from other species have been developed. These include language, large brain, the ability to construct and use complex tools, as well as the ability to adapt to cultural differences.
Evolution occurs when genetic changes allow members of a population to better adapt to their environment. Natural selection is the process that drives this change. Certain characteristics are more desirable than others. The ones who are better adjusted are more likely to pass on their genes to the next generation. This is the way all species evolve and is the basis for the theory of evolution.
Scientists refer to this as the "law of natural selection." The law states that species that have a common ancestor, tend to develop similar characteristics over time. This is because those traits make it easier for them to survive and reproduce in their natural environment.
Every living thing has a DNA molecule that contains the information necessary to direct their growth. The DNA molecule consists of base pairs that are arranged in a spiral around sugar molecules and phosphate molecules. The sequence of bases within each strand determines the phenotype which is the person's distinctive appearance and behavior. Different changes and reshuffling of genetic material (known as alleles) during reproduction causes variations in a population.
Fossils from the earliest human species, Homo erectus and Homo neanderthalensis have been discovered in Africa, Asia, and Europe. These fossils, despite a few variations in their appearance, all support the idea that modern humans' ancestors originated in Africa. Evidence from fossils and genetics suggest that early humans migrated out of Africa into Asia and then Europe.