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

The Academy's Evolution Site

Biology is a key concept in biology. The Academies have been active for a long time in helping those interested in science understand the concept of evolution and how it affects all areas of scientific exploration.

This site provides teachers, students and general readers with a wide range of learning resources about evolution. It also includes important video clips from NOVA and 에볼루션 게이밍 WGBH produced science programs on DVD.

Tree of Life

The Tree of Life is an ancient symbol that represents the interconnectedness of life. It is seen in a variety of spiritual traditions and 에볼루션 무료체험 cultures as an emblem of unity and love. It also has many practical applications, like providing a framework for understanding the evolution of species and how they respond to changes in environmental conditions.

The earliest attempts to depict the biological world focused on separating species into distinct categories that were distinguished by their physical and metabolic characteristics1. These methods, which rely on the sampling of different parts of organisms, or fragments of DNA have greatly increased the diversity of a tree of Life2. However, these trees are largely made up of eukaryotes. Bacterial diversity is not represented in a large way3,4.

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

Despite the dramatic expansion of the Tree of Life through genome sequencing, a lot of biodiversity remains to be discovered. This is particularly true of microorganisms, which can be difficult to cultivate and are usually only present in a single sample5. A recent analysis of all genomes produced a rough draft of the Tree of Life. This includes a wide range of archaea, bacteria and other organisms that have not yet been isolated, or the diversity of which is not thoroughly understood6.

The 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 many ways, including identifying new drugs, combating diseases and improving crops. The information is also incredibly valuable for conservation efforts. It can help biologists identify the areas most likely to contain cryptic species with potentially important metabolic functions that may be at risk of anthropogenic changes. While funding to protect biodiversity are important, the most effective way to conserve the biodiversity of the world is to equip more people in developing nations with the information they require to take action locally and encourage conservation.

Phylogeny

A phylogeny, also known as an evolutionary tree, reveals the relationships between groups of organisms. Scientists can create an phylogenetic chart which shows the evolution of taxonomic groups using molecular data and morphological differences or similarities. Phylogeny plays a crucial role in understanding genetics, biodiversity and evolution.

A basic phylogenetic Tree (see Figure PageIndex 10 ) identifies the relationships between organisms with similar traits that have evolved from common ancestral. These shared traits could be analogous, or homologous. Homologous traits are similar in their evolutionary origins while analogous traits appear like they do, but don't have the same ancestors. Scientists arrange similar traits into a grouping called a the clade. For instance, all of the organisms that make up a clade have the characteristic of having amniotic egg and evolved from a common ancestor who had these eggs. The clades are then linked to create a phylogenetic tree to determine the organisms with the closest relationship.

Scientists make use of DNA or RNA molecular information to construct a phylogenetic graph that is more accurate and detailed. This data is more precise than the morphological data and gives evidence of the evolutionary history of an individual or group. Researchers can use Molecular Data to estimate the evolutionary age of organisms and identify how many organisms have an ancestor common to all.

The phylogenetic relationships of a species can be affected by a variety of factors that include the phenomenon of phenotypicplasticity. This is a type behavior that alters as a result of particular environmental conditions. This can cause a characteristic to appear more resembling to one species than another, obscuring the phylogenetic signals. However, this problem can be solved through the use of techniques such as cladistics that include a mix of analogous and 에볼루션 슬롯 게이밍 (brainfine8.bravejournal.net) homologous features into the tree.

Additionally, phylogenetics can aid in predicting the length and speed of speciation. This information can help conservation biologists decide which species they should protect from extinction. Ultimately, it is the preservation of phylogenetic diversity that will lead to an ecologically balanced and complete ecosystem.

Evolutionary Theory

The central theme of evolution is that organisms develop distinct characteristics over time due to their interactions with their environment. Several theories of evolutionary change have been proposed by a wide variety 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 requirements and needs, the Swedish botanist Carolus Linnaeus (1707-1778) who developed the modern hierarchical taxonomy Jean-Baptiste Lamarck (1744-1829) who suggested that use or disuse of traits cause changes that could be passed onto offspring.

In the 1930s and 에볼루션 바카라사이트 1940s, ideas from a variety of fields--including genetics, natural selection, and particulate inheritance--came together to form the modern synthesis of evolutionary theory which explains how evolution occurs through the variation of genes within a population, and how these variants change in time as a result of natural selection. This model, known as genetic drift, mutation, gene flow and sexual selection, is the foundation of modern evolutionary biology and is mathematically described.

Recent discoveries in the field of evolutionary developmental biology have revealed how variations can be introduced to a species through mutations, genetic drift and reshuffling of genes during sexual reproduction and migration between populations. These processes, in conjunction with others, such as directional selection and gene erosion (changes in the frequency of genotypes over time) can lead to evolution. Evolution is defined as changes in the genome over time, as well as changes in phenotype (the expression of genotypes in individuals).

Incorporating evolutionary thinking into all areas of biology education can increase students' understanding of phylogeny and evolution. In a study by Grunspan and co. It was demonstrated that teaching students about the evidence for evolution increased their understanding of evolution in a college-level course in biology. For more information on how to teach about evolution, please read The Evolutionary Potential in all Areas of Biology and Thinking Evolutionarily: A Framework for Infusing Evolution in Life Sciences Education.

Evolution in Action

Traditionally, scientists have studied evolution by looking back, studying fossils, comparing species, and observing living organisms. However, evolution isn't something that happened in the past. It's an ongoing process that is happening right now. The virus reinvents itself to avoid new drugs and bacteria evolve to resist antibiotics. Animals alter their behavior because of the changing environment. The results are usually evident.

It wasn't until late 1980s that biologists began realize that natural selection was in action. The key is the fact that different traits result in a different rate of survival and reproduction, and can be passed down from one generation to the next.

In the past, when one particular allele - the genetic sequence that determines coloration--appeared in a group of interbreeding organisms, it might quickly become more common than other alleles. Over time, this would mean that the number of moths sporting black pigmentation in a group could increase. The same is true for 에볼루션 슬롯 many other characteristics--including morphology and behavior--that vary among populations of organisms.

It is easier to see evolution when an organism, like bacteria, has a high generation turnover. Since 1988, Richard Lenski, a biologist, has been tracking twelve populations of E.coli that are descended from one strain. Samples from each population have been taken 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, consequently the rate at which it evolves. It also proves that evolution takes time, a fact that some people are unable to accept.

Microevolution can also be seen in the fact that mosquito genes that confer resistance to pesticides are more prevalent in areas that have used insecticides. This is because pesticides cause an exclusive pressure that favors those with resistant genotypes.

The rapid pace of evolution taking place has led to an increasing appreciation of its importance in a world shaped by human activity--including climate changes, pollution and the loss of habitats that prevent many species from adjusting. Understanding evolution can aid you in making better decisions regarding the future of the planet and its inhabitants.