• 목록
• 답변
• 글쓰기
• 게시판 리스트 옵션
  • 수정
  • 삭제

The Academy's Evolution Site

Biology is one of the most important concepts in biology. The Academies have long been involved in helping those interested in science comprehend the concept of evolution and how it permeates all areas of scientific exploration.

This site offers a variety of resources for teachers, students and general readers of evolution. It contains the most important video clips from NOVA and WGBH's science programs on DVD.

Tree of Life

The Tree of Life is an ancient symbol that symbolizes the interconnectedness of all life. It is used in many spiritual traditions and cultures as symbolizing unity and love. It also has important practical applications, like providing a framework for understanding the evolution of species and how they respond to changes in the environment.

Early attempts to describe the biological world were based on categorizing organisms based on their metabolic and physical characteristics. These methods, 에볼루션 코리아 based on sampling of different parts of living organisms or on sequences of short fragments of their DNA, significantly increased the variety that could be included in the tree of life2. However these trees are mainly made up of eukaryotes. Bacterial diversity remains vastly underrepresented3,4.

By avoiding the need for direct experimentation and observation genetic techniques have made it possible to represent the Tree of Life in a more precise way. We can construct trees using molecular methods such as the small subunit ribosomal gene.

The Tree of Life has been significantly expanded by genome sequencing. However, there is still much diversity to be discovered. This is especially relevant to microorganisms that are difficult to cultivate and which are usually only found in a single specimen5. A recent analysis of all genomes known to date has produced a rough draft of the Tree of Life, including many bacteria and archaea that are not isolated and their diversity is not fully understood6.

This expanded Tree of Life is particularly beneficial in assessing the biodiversity of an area, helping to determine if specific habitats require protection. This information can be utilized in a range of ways, from identifying the most effective remedies to fight diseases to enhancing crops. This information is also extremely beneficial to conservation efforts. It can help biologists identify areas most likely to have cryptic species, which could have vital metabolic functions, and could be susceptible to changes caused by humans. While conservation funds are essential, the best method to protect the world's biodiversity is to empower more people in developing nations with the knowledge they need to act locally and support conservation.

Phylogeny

A phylogeny, also known as an evolutionary tree, reveals the connections between groups of organisms. Scientists can build an phylogenetic chart which shows the evolutionary relationships between taxonomic groups based on molecular data and morphological differences or similarities. The phylogeny of a tree plays an important role in understanding biodiversity, genetics and evolution.

A basic phylogenetic Tree (see Figure PageIndex 10 Identifies the relationships between organisms with similar traits and evolved from an ancestor that shared traits. These shared traits are either analogous or homologous. Homologous characteristics are identical in their evolutionary path. Analogous traits may look like they are, but they do not have the same ancestry. Scientists organize similar traits into a grouping known as a the clade. For instance, all of the organisms in a clade share the trait of having amniotic eggs. They evolved from a common ancestor who had eggs. A phylogenetic tree is constructed by connecting the clades to identify the organisms which are the closest to each other.

Scientists make use of DNA or RNA molecular data to create a phylogenetic chart which is more precise and detailed. This data is more precise than morphological information and provides evidence of the evolution history of an organism or group. Researchers can utilize Molecular Data to estimate the evolutionary age of organisms and determine the number of organisms that share a common ancestor.

The phylogenetic relationships of organisms are influenced by many factors, including phenotypic flexibility, a type of behavior that changes in response to specific environmental conditions. This can make a trait appear more resembling to one species than to the other, obscuring the phylogenetic signals. However, this problem can be cured by the use of methods such as cladistics which combine similar and homologous traits into the tree.

Additionally, phylogenetics can help predict the time and pace of speciation. This information can assist conservation biologists in deciding which species to save from disappearance. In the end, it's the preservation of phylogenetic diversity which will create an ecosystem that is complete and balanced.

Evolutionary Theory

The main idea behind evolution is that organisms change over time as a result of their interactions with their environment. A variety of theories about evolution have been developed by a wide range of scientists such as the Islamic naturalist Nasir al-Din al-Tusi (1201-1274) who believed that an organism would evolve slowly according to its needs, the Swedish botanist Carolus Linnaeus (1707-1778) who developed the modern hierarchical taxonomy Jean-Baptiste Lamarck (1744-1829) who suggested that the use or non-use of traits cause changes that could be passed onto offspring.

In the 1930s and 1940s, concepts from various fields, including genetics, natural selection, and particulate inheritance--came together to form the current synthesis of evolutionary theory, which defines how evolution occurs through the variations of genes within a population and how those variations change in time due to natural selection. This model, which includes genetic drift, mutations as well as gene flow and sexual selection can be mathematically described mathematically.

Recent developments in the field of evolutionary developmental biology have shown how variation can be introduced to a species through mutations, genetic drift, reshuffling genes during sexual reproduction and migration between populations. These processes, 에볼루션 슬롯게임 as well as others, such as directional selection and gene erosion (changes to the frequency of genotypes over time) can result in evolution. Evolution is defined as changes in the genome over time, as well as changes in the phenotype (the expression of genotypes in an individual).

Students can gain a better understanding of phylogeny by incorporating evolutionary thinking in all aspects of biology. A recent study by Grunspan and colleagues, for example revealed that teaching students about the evidence for evolution helped students accept the concept of evolution in a college-level biology course. For more information on how to teach evolution, see The Evolutionary Power of Biology in all Areas of Biology or Thinking Evolutionarily: a Framework for Infusing Evolution into Life Sciences Education.

Evolution in Action

Scientists have traditionally looked at evolution through the past, studying fossils, 에볼루션 바카라 사이트 and comparing species. They also observe living organisms. Evolution is not a past event, but an ongoing process. The virus reinvents itself to avoid new antibiotics and bacteria transform to resist antibiotics. Animals adapt their behavior because of a changing world. The changes that occur are often apparent.

It wasn't until late 1980s that biologists understood that natural selection can be observed in action as well. The reason is that different traits have different rates of survival and reproduction (differential fitness), and can be transferred from one generation to the next.

In the past, when one particular allele--the genetic sequence that controls coloration - was present in a population of interbreeding species, it could quickly become more common than all other alleles. Over time, that would mean the number of black moths in a particular population could rise. The same is true for many other characteristics--including morphology and behavior--that vary among populations of organisms.

It is easier to see evolutionary change when an organism, like bacteria, has a high generation turnover. Since 1988, Richard Lenski, a biologist, 에볼루션게이밍 has tracked twelve populations of E.coli that are descended from one strain. The samples of each population have been collected regularly, and more than 500.000 generations of E.coli have passed.

Lenski's research has shown that a mutation can dramatically alter the speed at which a population reproduces and, 에볼루션바카라 consequently the rate at which it evolves. It also proves that evolution is slow-moving, a fact that some people find hard to accept.

Microevolution can also be seen in the fact that mosquito genes for resistance to pesticides are more prevalent in populations that have used insecticides. This is because the use of pesticides causes a selective pressure that favors those who have resistant genotypes.

The rapidity of evolution has led to an increasing awareness of its significance particularly in a world that is largely shaped by human activity. This includes the effects of climate change, pollution and habitat loss that hinders many species from adapting. Understanding the evolution process can assist you in making better choices about the future of the planet and its inhabitants.