The Berkeley Evolution Site

Teachers and students who browse the Berkeley site will find resources to aid in understanding and teaching 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 in time, creatures more adaptable to changing environments do better than those that do not become extinct. This process of evolution is the basis of science.

What is Evolution?

The term "evolution" has a variety of nonscientific meanings, such as "progress" or "descent with modification." It is an academic term that is used to describe the process of changing traits over time in organisms or species. This change is based in biological terms on natural selection and drift.

Evolution is a key concept in modern biology. It is an established theory that has stood up to the tests of time and thousands of scientific tests. In contrast to other theories in science, such as the Copernican theory or 에볼루션 바카라사이트 룰렛 (look here) the germ theory of disease, the evolution theory does not address issues of religious belief or the existence of God.

Early evolutionists, such as Jean-Baptiste Lamarck and Erasmus Darwin (Charles's grandfather), believed that certain physical traits were predetermined to change, in a gradual manner, as time passes. They called this the "Ladder of Nature" or the 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 asserts that different species of organisms share an ancestry that can be proven through fossils and other evidence. This is the current view of evolution, which is supported by a variety of scientific fields which include molecular biology.

Scientists aren't sure how organisms evolved but they are sure that natural selection and genetic drift are the primary reason for the evolution of life. People with traits that are advantageous are more likely to survive and reproduce, and these individuals pass their genes on to the next generation. As time passes this leads to an accumulation of changes to the gene pool that gradually lead to new species and types.

Certain scientists use the term"evolution" to refer to large-scale changes, like the formation of one species from an ancestral one. Some scientists, like population geneticists, define evolution in a broad sense, using the term "net change" to refer to the change in allele frequency over generations. Both definitions are correct and acceptable, however certain scientists argue that allele frequency definitions miss important aspects of the evolutionary process.

Origins of Life

The development of life is a key step in the process of evolution. The emergene changes may result from the response to environmental pressures as discussed in the entry on Darwinism (see the entry on Charles Darwin for background), or from natural selection.

This mechanism also increases the number of genes that offer the advantage of survival for the species, leading to an overall change in the appearance of a group. These changes in evolutionary patterns are caused by mutations, reshuffling of genes in the process of sexual reproduction, and also by gene flow.

While mutation and reshuffling of genes are common in all living organisms The process through which beneficial mutations are more frequent is referred to as natural selection. As mentioned above, those who have the advantageous characteristic have a higher reproduction rate than those who do not. Over the course of many generations, this difference in the number of offspring produced can result in gradual changes in the number of advantageous traits within a group of.

An excellent example is the growing beak size on various species of finches on the Galapagos Islands, which have developed different beak shapes that allow them to easily access food in their new habitat. These changes in shape and 에볼루션 사이트 form can aid in the creation of new organisms.

The majority of changes are caused by a single mutation, however sometimes multiple occur at the same time. Most of these changes are neutral or even detrimental 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 their frequency in the population over time. This is the way of natural selection, and it can eventually result in the cumulative changes that eventually result in a new species.

Some people think that evolution is a form of soft inheritance that is the belief that inherited traits can be changed through conscious choice or abuse. This is a misunderstanding of the nature of evolution, and of the actual biological processes that cause it. 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

Modern humans (Homo Sapiens) evolved from primates, a species of mammal species which includes chimpanzees as well as gorillas. The earliest human fossils show that our ancestors were bipeds. They were walkers with two legs. Genetic and biological similarities suggest that we are closely related to Chimpanzees. In fact, our closest relatives are chimpanzees from the Pan genus. This includes pygmy as well as bonobos. The last common ancestor of modern humans and chimpanzees was between 8 and 6 million years ago.

As time has passed humans have developed a range of characteristics, such as bipedalism and the use of fire. They also created advanced tools. It is only in the last 100,000 years or so that the majority of the important characteristics that differentiate us from other species have emerged. These include language, a large brain, the capacity to create and utilize sophisticated tools, and a the ability to adapt to cultural differences.

The process of evolution occurs when genetic changes enable members of an organization to better adapt to their environment. Natural selection is the mechanism that drives this adaptation. Certain characteristics are more desirable than others. People with better adaptations are more likely to pass on their genes to the next generation. This is how all species evolve and is the basis of the theory of evolution.

Scientists refer to it as the "law of Natural Selection." The law states that species which share a common ancestor tend to develop similar traits over time. This is because those characteristics make it easier for them to live and reproduce in their environments.

All organisms possess an molecule called DNA that holds the information necessary to direct their growth. The structure of DNA is made of base pairs arranged in a spiral around sugar and phosphate molecules. The sequence of bases within each strand determines the phenotype or the individual's unique appearance and behavior. Different mutations and reshufflings of the genetic material (known as alleles) during reproduction causes variations in a population.

Fossils from the earliest human species Homo erectus, as well as Homo neanderthalensis have been found in Africa, [Redirect Only] Asia and Europe. While there are some differences between them the fossils all support the hypothesis that modern humans first came into existence in Africa. The fossil evidence and genetic evidence suggest that early humans migrated out of Africa into Asia and then Europe.