The Academy's Evolution Site
Biology is a key concept in biology. The Academies have long been involved in helping people who are interested in science understand the theory of evolution and how it influences all areas of scientific exploration.
This site offers a variety of sources 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 represents the interconnectedness of life. It is an emblem of love and unity across many cultures. It has many practical applications as well, 에볼루션 블랙잭 including providing a framework to understand the history of species and how they respond to changing environmental conditions.
Early attempts to represent the world of biology were founded on categorizing organisms on their physical and metabolic characteristics. These methods, which depend on the collection of various parts of organisms or fragments of DNA have significantly increased the diversity of a Tree of Life2. However the trees are mostly made up of eukaryotes. Bacterial diversity is not represented in a large way3,4.
In avoiding the necessity of direct observation and experimentation, genetic techniques have enabled us to depict the Tree of Life in a much more accurate way. We can create trees by 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 a lot of diversity to be discovered. This is particularly relevant to microorganisms that are difficult to cultivate, and are usually found in a single specimen5. A recent study of all known genomes has produced a rough draft of the Tree of Life, including a large number of archaea and bacteria that have not been isolated and their diversity is not fully understood6.
The expanded Tree of Life is particularly beneficial in assessing the biodiversity of an area, which can help to determine if specific habitats require special protection. This information can be used in a range of ways, from identifying the most effective medicines to combating disease to improving crops. It is also beneficial to conservation efforts. It can help biologists identify the areas that are most likely to contain cryptic species that could have important metabolic functions that may be at risk from anthropogenic change. While conservation funds are important, the best way to conserve the world's biodiversity is to empower the people of developing nations with the information they require to take action locally and encourage conservation.
Phylogeny
A phylogeny, also called an evolutionary tree, shows the connections between different groups of organisms. Scientists can construct an phylogenetic chart which shows the evolutionary relationships between taxonomic groups based on molecular data and morphological similarities or differences. Phylogeny plays a crucial role in understanding biodiversity, genetics and evolution.
A basic phylogenetic Tree (see Figure PageIndex 10 Finds the connections between organisms with similar characteristics and have evolved from a common ancestor. These shared traits can be analogous, or homologous. Homologous traits are similar in their evolutionary roots and analogous traits appear similar but do not have the same ancestors. Scientists put similar traits into a grouping referred to as a clade. For ecuadortenisclub.com instance, all the organisms in a clade share the trait of having amniotic eggs and evolved from a common ancestor which had eggs. The clades are then connected to form a phylogenetic branch to determine which organisms have the closest relationship.
Scientists make use of DNA or RNA molecular data to build a phylogenetic chart that is more accurate and precise. This information is more precise than morphological information and gives evidence of the evolutionary history of an individual or 에볼루션 코리아 group. The use of molecular data lets researchers determine the number of species that share an ancestor common to them and estimate their evolutionary age.
The phylogenetic relationship can be affected by a variety of factors such as phenotypicplasticity. This is a kind of behavior that alters as a result of specific environmental conditions. This can cause a trait to appear more similar in one species than other species, which can obscure the phylogenetic signal. This problem can be mitigated by using cladistics, which incorporates an amalgamation of homologous and analogous features in the tree.
In addition, phylogenetics can help predict the length and 에볼루션 코리아 (Https://Theflatearth.Win/Wiki/Post:Unexpected_Business_Strategies_That_Aided_Evolution_Gaming_To_Succeed) speed of speciation. This information can help conservation biologists decide the species they should safeguard from the threat of extinction. In the end, it's the preservation of phylogenetic diversity which will create a complete and balanced ecosystem.
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 proposed by a variety of scientists including 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 conceived modern hierarchical taxonomy, and Jean-Baptiste Lamarck (1744-1829) who suggested that the use or non-use of traits can cause changes that can be passed on to the offspring.
In the 1930s & 1940s, theories from various fields, such as genetics, natural selection, and particulate inheritance, merged to create a modern evolutionary theory. This defines how evolution occurs by the variations in genes within the population, and how these variants change with time due to natural selection. This model, 에볼루션 which encompasses mutations, genetic drift as well as gene flow and sexual selection can be mathematically described.
Recent developments in the field of evolutionary developmental biology have shown the ways in which variation can be introduced to a species via genetic drift, mutations or reshuffling of genes in sexual reproduction and the movement between populations. These processes, along with other ones like directional selection and genetic erosion (changes in the frequency of an individual's genotype over time) can result in evolution that is defined as changes in the genome of the species over time, and also the change in phenotype as time passes (the expression of the genotype in an individual).
Students can gain a better understanding of phylogeny by incorporating evolutionary thinking in all aspects of biology. In a recent study by Grunspan and colleagues., it was shown that teaching students about the evidence for evolution boosted their understanding of evolution in the course of a college biology. For more details on how to teach about 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--analyzing fossils and comparing species. They also observe living organisms. But evolution isn't a thing that happened in the past. It's an ongoing process that is that is taking place right now. Bacteria mutate and resist antibiotics, viruses re-invent themselves and elude new medications and animals alter their behavior in response to the changing environment. The resulting changes are often easy to see.
It wasn't until late 1980s that biologists realized that natural selection could 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, if an allele - the genetic sequence that determines colour was present in a population of organisms that interbred, it could become more prevalent than any other allele. In time, this could mean the number of black moths in the population could increase. The same is true for many other characteristics--including morphology and behavior--that vary among populations of organisms.
Monitoring evolutionary changes in action is easier when a particular species has a rapid generation turnover like bacteria. Since 1988, Richard Lenski, a biologist, has studied twelve populations of E.coli that descend from one strain. The samples of each population have been collected regularly and more than 50,000 generations of E.coli have been observed to have passed.
Lenski's research has shown that a mutation can profoundly alter the efficiency with the rate at which a population reproduces, and consequently the rate at which it evolves. It also demonstrates that evolution is slow-moving, a fact that many find hard to accept.
Microevolution can also be seen in the fact that mosquito genes for resistance to pesticides are more common in populations that have used insecticides. That's because the use of pesticides creates a selective pressure that favors people with resistant genotypes.
The speed of evolution taking place has led to a growing awareness of its significance in a world shaped by human activities, including climate change, pollution, and the loss of habitats that hinder the species from adapting. Understanding the evolution process will help us make better decisions about the future of our planet, and the lives of its inhabitants.
Biology is a key concept in biology. The Academies have long been involved in helping people who are interested in science understand the theory of evolution and how it influences all areas of scientific exploration.
This site offers a variety of sources 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 represents the interconnectedness of life. It is an emblem of love and unity across many cultures. It has many practical applications as well, 에볼루션 블랙잭 including providing a framework to understand the history of species and how they respond to changing environmental conditions.
Early attempts to represent the world of biology were founded on categorizing organisms on their physical and metabolic characteristics. These methods, which depend on the collection of various parts of organisms or fragments of DNA have significantly increased the diversity of a Tree of Life2. However the trees are mostly made up of eukaryotes. Bacterial diversity is not represented in a large way3,4.
In avoiding the necessity of direct observation and experimentation, genetic techniques have enabled us to depict the Tree of Life in a much more accurate way. We can create trees by 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 a lot of diversity to be discovered. This is particularly relevant to microorganisms that are difficult to cultivate, and are usually found in a single specimen5. A recent study of all known genomes has produced a rough draft of the Tree of Life, including a large number of archaea and bacteria that have not been isolated and their diversity is not fully understood6.
The expanded Tree of Life is particularly beneficial in assessing the biodiversity of an area, which can help to determine if specific habitats require special protection. This information can be used in a range of ways, from identifying the most effective medicines to combating disease to improving crops. It is also beneficial to conservation efforts. It can help biologists identify the areas that are most likely to contain cryptic species that could have important metabolic functions that may be at risk from anthropogenic change. While conservation funds are important, the best way to conserve the world's biodiversity is to empower the people of developing nations with the information they require to take action locally and encourage conservation.
Phylogeny
A phylogeny, also called an evolutionary tree, shows the connections between different groups of organisms. Scientists can construct an phylogenetic chart which shows the evolutionary relationships between taxonomic groups based on molecular data and morphological similarities or differences. Phylogeny plays a crucial role in understanding biodiversity, genetics and evolution.
A basic phylogenetic Tree (see Figure PageIndex 10 Finds the connections between organisms with similar characteristics and have evolved from a common ancestor. These shared traits can be analogous, or homologous. Homologous traits are similar in their evolutionary roots and analogous traits appear similar but do not have the same ancestors. Scientists put similar traits into a grouping referred to as a clade. For ecuadortenisclub.com instance, all the organisms in a clade share the trait of having amniotic eggs and evolved from a common ancestor which had eggs. The clades are then connected to form a phylogenetic branch to determine which organisms have the closest relationship.
Scientists make use of DNA or RNA molecular data to build a phylogenetic chart that is more accurate and precise. This information is more precise than morphological information and gives evidence of the evolutionary history of an individual or 에볼루션 코리아 group. The use of molecular data lets researchers determine the number of species that share an ancestor common to them and estimate their evolutionary age.
The phylogenetic relationship can be affected by a variety of factors such as phenotypicplasticity. This is a kind of behavior that alters as a result of specific environmental conditions. This can cause a trait to appear more similar in one species than other species, which can obscure the phylogenetic signal. This problem can be mitigated by using cladistics, which incorporates an amalgamation of homologous and analogous features in the tree.
In addition, phylogenetics can help predict the length and 에볼루션 코리아 (Https://Theflatearth.Win/Wiki/Post:Unexpected_Business_Strategies_That_Aided_Evolution_Gaming_To_Succeed) speed of speciation. This information can help conservation biologists decide the species they should safeguard from the threat of extinction. In the end, it's the preservation of phylogenetic diversity which will create a complete and balanced ecosystem.
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 proposed by a variety of scientists including 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 conceived modern hierarchical taxonomy, and Jean-Baptiste Lamarck (1744-1829) who suggested that the use or non-use of traits can cause changes that can be passed on to the offspring.
In the 1930s & 1940s, theories from various fields, such as genetics, natural selection, and particulate inheritance, merged to create a modern evolutionary theory. This defines how evolution occurs by the variations in genes within the population, and how these variants change with time due to natural selection. This model, 에볼루션 which encompasses mutations, genetic drift as well as gene flow and sexual selection can be mathematically described.
Recent developments in the field of evolutionary developmental biology have shown the ways in which variation can be introduced to a species via genetic drift, mutations or reshuffling of genes in sexual reproduction and the movement between populations. These processes, along with other ones like directional selection and genetic erosion (changes in the frequency of an individual's genotype over time) can result in evolution that is defined as changes in the genome of the species over time, and also the change in phenotype as time passes (the expression of the genotype in an individual).
Students can gain a better understanding of phylogeny by incorporating evolutionary thinking in all aspects of biology. In a recent study by Grunspan and colleagues., it was shown that teaching students about the evidence for evolution boosted their understanding of evolution in the course of a college biology. For more details on how to teach about 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--analyzing fossils and comparing species. They also observe living organisms. But evolution isn't a thing that happened in the past. It's an ongoing process that is that is taking place right now. Bacteria mutate and resist antibiotics, viruses re-invent themselves and elude new medications and animals alter their behavior in response to the changing environment. The resulting changes are often easy to see.
It wasn't until late 1980s that biologists realized that natural selection could 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, if an allele - the genetic sequence that determines colour was present in a population of organisms that interbred, it could become more prevalent than any other allele. In time, this could mean the number of black moths in the population could increase. The same is true for many other characteristics--including morphology and behavior--that vary among populations of organisms.
Monitoring evolutionary changes in action is easier when a particular species has a rapid generation turnover like bacteria. Since 1988, Richard Lenski, a biologist, has studied twelve populations of E.coli that descend from one strain. The samples of each population have been collected regularly and more than 50,000 generations of E.coli have been observed to have passed.
Lenski's research has shown that a mutation can profoundly alter the efficiency with the rate at which a population reproduces, and consequently the rate at which it evolves. It also demonstrates that evolution is slow-moving, a fact that many find hard to accept.
Microevolution can also be seen in the fact that mosquito genes for resistance to pesticides are more common in populations that have used insecticides. That's because the use of pesticides creates a selective pressure that favors people with resistant genotypes.
The speed of evolution taking place has led to a growing awareness of its significance in a world shaped by human activities, including climate change, pollution, and the loss of habitats that hinder the species from adapting. Understanding the evolution process will help us make better decisions about the future of our planet, and the lives of its inhabitants.