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

The Academy's Evolution Site

Biology is one of the most central concepts in biology. The Academies are involved in helping those who are interested in science to comprehend the evolution theory and how it can be applied across all areas of scientific research.

This site provides teachers, students and general readers with a range of learning resources about evolution. It includes the most important video clips from NOVA and WGBH's science programs on DVD.

Tree of Life

The Tree of Life, an ancient symbol, represents the interconnectedness of all life. It is an emblem of love and unity across many cultures. It has many practical applications as well, including providing a framework for understanding the history of species and how they respond to changes in environmental conditions.

Early attempts to represent the world of biology were built on categorizing organisms based on their physical and metabolic characteristics. These methods, which rely on the sampling of different parts of organisms, or DNA fragments have significantly increased the diversity of a tree of Life2. However these trees are mainly composed of eukaryotes; bacterial diversity is still largely unrepresented3,4.

Genetic techniques have significantly expanded our ability to visualize the Tree of Life by circumventing the requirement for 에볼루션코리아 direct observation and experimentation. We can create trees by using molecular methods like the small-subunit ribosomal gene.

The Tree of Life has been greatly expanded thanks to genome sequencing. However, there is still much diversity to be discovered. This is particularly true for microorganisms that are difficult to cultivate and are often only found in a single sample5. A recent analysis of all genomes produced an initial draft of a Tree of Life. This includes a wide range of archaea, bacteria, and other organisms that haven't yet been isolated or the diversity of which is not well understood6.

This expanded Tree of Life can be used to assess the biodiversity of a specific region and determine if particular habitats require special protection. The information can be used in a range of ways, from identifying the most effective treatments to fight disease to improving crops. The information is also incredibly useful to conservation efforts. It helps biologists discover areas that are most likely to have cryptic species, which may have important metabolic functions and are susceptible to changes caused by humans. While conservation funds are important, the most effective method to preserve the world's biodiversity is to empower more people in developing nations with the information they require to act locally and promote conservation.

Phylogeny

A phylogeny (also known as an evolutionary tree) shows the relationships between organisms. Scientists can create a phylogenetic chart that shows the evolution of taxonomic groups based on molecular data and morphological similarities or differences. Phylogeny is essential in understanding the evolution of biodiversity, evolution and genetics.

A basic phylogenetic Tree (see Figure PageIndex 10 ) is a method of identifying the relationships between organisms that share similar traits that have evolved from common ancestors. These shared traits are either homologous or analogous. Homologous traits share their evolutionary roots while analogous traits appear similar but do not have the same ancestors. Scientists combine similar traits into a grouping referred to as a the clade. For 에볼루션 코리아 example, all of the organisms in a clade share the characteristic of having amniotic egg and evolved from a common ancestor which had eggs. The clades are then connected to create a phylogenetic tree to determine the organisms with the closest relationship to.

Scientists make use of DNA or RNA molecular data to construct a phylogenetic graph that is more accurate and precise. This information is more precise and provides evidence of the evolutionary history of an organism. Researchers can utilize Molecular Data to determine the evolutionary age of organisms and identify how many species share the same ancestor.

Phylogenetic relationships can be affected by a number of factors such as the phenotypic plasticity. This is a kind of behaviour that can change due to unique environmental conditions. This can cause a trait to appear more resembling to one species than to the other, obscuring the phylogenetic signals. However, this issue can be reduced by the use of techniques such as cladistics which include a mix of similar and homologous traits into the tree.

In addition, phylogenetics can aid in predicting the length and speed of speciation. This information can help conservation biologists decide the species they should safeguard from extinction. In the end, it is the conservation of phylogenetic variety that will result in an ecosystem that is complete and balanced.

Evolutionary Theory

The central theme of evolution is that organisms acquire distinct characteristics over time based on their interactions with their surroundings. Many scientists have developed theories of evolution, 에볼루션바카라사이트 including the Islamic naturalist Nasir al-Din al-Tusi (1201-274) who believed that an organism would evolve according to its own requirements as well as the Swedish taxonomist Carolus Linnaeus (1707-1778) who developed the modern hierarchical taxonomy as well as Jean-Baptiste Lamarck (1844-1829), who suggested that the use or absence of traits can cause changes that are passed on to the next generation.

In the 1930s and 1940s, ideas from a variety of fields--including genetics, natural selection and particulate inheritance--came together to form the current evolutionary theory synthesis, which defines how evolution is triggered by the variation of genes within a population, and how those variants change over time due to natural selection. This model, called genetic drift mutation, gene flow, and sexual selection, is the foundation of modern evolutionary biology and can be mathematically described.

Recent discoveries in the field of evolutionary developmental biology have revealed how variations can be introduced to a species by genetic drift, mutations and reshuffling of genes during sexual reproduction, and even migration between populations. These processes, as well as others like directional selection and genetic erosion (changes in the frequency of a genotype over time) can lead to evolution, which is defined by change in the genome of the species over time and also the change in phenotype over time (the expression of the genotype in the individual).

Students can gain a better understanding of the concept of phylogeny through incorporating evolutionary thinking throughout all areas of biology. A recent study by Grunspan and colleagues, for example, showed that teaching about the evidence supporting evolution increased students' understanding of evolution in a college biology class. To learn more about how to teach about evolution, please read The Evolutionary Potential in All Areas of Biology and Thinking Evolutionarily: A Framework for Infusing Evolution into Life Sciences Education.

Evolution in Action

Traditionally scientists have studied evolution by looking back, studying fossils, comparing species, 에볼루션 카지노 and studying living organisms. Evolution is not a distant event, but a process that continues today. Bacteria evolve and resist antibiotics, viruses re-invent themselves and elude new medications, and animals adapt their behavior to a changing planet. The results are usually easy to see.

However, it wasn't until late 1980s that biologists understood that natural selection could be seen in action, as well. The key is the fact that different traits result in a different rate of survival and reproduction, and they can be passed on from one generation to another.

In the past, if a certain allele - the genetic sequence that determines color - appeared in a population of organisms that interbred, it might become more common than any other allele. In time, this could mean that the number of moths that have black pigmentation in a group could increase. The same is true for many other characteristics--including morphology and behavior--that vary among populations of organisms.

It is easier to observe evolutionary change when a species, such as bacteria, has a rapid generation turnover. Since 1988, biologist Richard Lenski has been tracking twelve populations of E. coli that descended from a single strain; samples of each population are taken every day and more than 500.000 generations have passed.

Lenski's research has revealed that a mutation can profoundly alter the rate at which a population reproduces--and so, the rate at which it changes. It also shows that evolution takes time, which is hard for some to accept.

Microevolution can also be seen in the fact that mosquito genes that confer resistance to pesticides are more common in populations where insecticides have been used. This is because pesticides cause an enticement that favors those who have resistant genotypes.

The rapidity of evolution has led to a greater recognition of its importance particularly in a world that is largely shaped by human activity. This includes climate change, pollution, and habitat loss that prevents many species from adapting. Understanding evolution will help you make better decisions about the future of the planet and its inhabitants.