Buzzwords De-Buzzed: 10 More Ways Of Saying Evolution Site

The Academy's Evolution Site

Biological evolution is one of the most important concepts in biology. The Academies have been for a long time involved in helping people who are interested in science understand the theory of evolution and how it affects every area of scientific inquiry.

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

Tree of Life

The Tree of Life is an ancient symbol of the interconnectedness of all life. It is seen in a variety of religions and cultures as symbolizing unity and love. It also has many practical uses, 에볼루션 게이밍 (Sovren.Media) like providing a framework to understand the history of species and how they respond to changes in environmental conditions.

The earliest attempts to depict the biological world focused on the classification of organisms into distinct categories which were distinguished by their physical and metabolic characteristics1. These methods, which relied on the sampling of various parts of living organisms or small DNA fragments, significantly increased the variety that could be represented in a tree of life2. These trees are largely composed by eukaryotes and bacterial diversity is vastly underrepresented3,4.

By avoiding the necessity for direct experimentation and observation, genetic techniques have made it possible to represent the Tree of Life in a much more accurate way. In particular, molecular methods allow us to build trees by using sequenced markers like the small subunit of ribosomal RNA gene.

Despite the rapid growth of the Tree of Life through genome sequencing, a large amount of biodiversity remains to be discovered. This is particularly the case for microorganisms which are difficult to cultivate, and are usually found in one sample5. A recent analysis of all known genomes has produced a rough draft of the Tree of Life, including a large number of bacteria and archaea that have not been isolated, and their diversity is not fully understood6.

This expanded Tree of Life is particularly useful for assessing the biodiversity of an area, helping to determine if certain habitats require protection. The information is useful in many ways, including finding new drugs, fighting diseases and improving crops. This information is also extremely beneficial for conservation efforts. It helps biologists discover areas that are likely to have cryptic species, which could have important metabolic functions, and could be susceptible to human-induced change. While funds to protect biodiversity are crucial, ultimately the best way to ensure the preservation of biodiversity around the world is for more people in developing countries to be empowered with the necessary knowledge to act locally in order to promote conservation from within.

Phylogeny

A phylogeny (also known as an evolutionary tree) depicts the relationships between species. By using molecular information, morphological similarities and differences, or ontogeny (the course of development of an organism) scientists can construct a phylogenetic tree that illustrates the evolutionary relationship between taxonomic groups. Phylogeny is essential in understanding evolution, biodiversity 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 ancestral. These shared traits could be either homologous or analogous. Homologous traits share their underlying evolutionary path, while analogous traits look like they do, but don't have the identical origins. Scientists put similar traits into a grouping called a the clade. For instance, all the organisms that make up a clade share the trait of having amniotic eggs and evolved from a common ancestor who had these eggs. The clades are then linked to form a phylogenetic branch to determine which organisms have the closest connection to each other.

To create a more thorough and accurate phylogenetic tree, scientists rely on molecular information from DNA or RNA to identify the relationships between organisms. This data is more precise than morphological data and provides evidence of the evolution history of an individual or group. Researchers can utilize Molecular Data to calculate the age of evolution of living organisms and discover how many organisms have an ancestor common to all.

The phylogenetic relationships of organisms are influenced by many factors, including phenotypic flexibility, an aspect of behavior that changes in response to specific environmental conditions. This can cause a characteristic to appear more similar to one species than another, obscuring the phylogenetic signal. However, this problem can be reduced by the use of techniques such as cladistics which incorporate a combination of homologous and analogous features into the tree.

Additionally, phylogenetics can help determine the duration and speed at which speciation occurs. This information can assist conservation biologists make decisions about which species to protect from the threat of extinction. Ultimately, it is the preservation of phylogenetic diversity which will lead to a complete and balanced ecosystem.

Evolutionary Theory

The central theme of evolution is that organisms develop distinct characteristics over time as a result of their interactions with their surroundings. Many scientists have developed theories of evolution, such as the Islamic naturalist Nasir al-Din al-Tusi (1201-274), who believed that an organism would evolve according to its own requirements and needs, the Swedish taxonomist Carolus Linnaeus (1707-1778), 에볼루션 바카라 who created the modern hierarchical system of taxonomy and Jean-Baptiste Lamarck (1844-1829), who believed that the use or non-use of traits can lead to changes that are passed on to the next generation.

In the 1930s and 1940s, ideas from various fields, including natural selection, genetics, and particulate inheritance -- came together to form the modern evolutionary theory synthesis, which defines how evolution happens through the variations of genes within a population and how those variations change over time as a result of natural selection. This model, 에볼루션 게이밍 known as genetic drift mutation, gene flow and sexual selection, is a key element of the current evolutionary biology and can be mathematically described.

Recent developments in the field of evolutionary developmental biology have shown that genetic variation can be introduced into a species via genetic drift, mutation, and reshuffling of genes in sexual reproduction, as well as through migration between populations. These processes, along with others such as directional selection and gene erosion (changes in frequency of genotypes over time) can lead to evolution. Evolution is defined as changes in the genome over time and changes in phenotype (the expression of genotypes in individuals).

Students can better understand the concept of phylogeny through incorporating evolutionary thinking in all areas of biology. In a recent study conducted by Grunspan and co. It was found that teaching students about the evidence for evolution increased their understanding of evolution in a college-level course in biology. For more details on how to teach evolution read The Evolutionary Potential in All Areas of Biology or Thinking Evolutionarily A Framework for Integrating Evolution into Life Sciences Education.

Evolution in Action

Traditionally, scientists have studied evolution by studying fossils, comparing species, and studying living organisms. Evolution is not a past event; it is a process that continues today. Viruses reinvent themselves to avoid new medications and bacteria mutate to resist antibiotics. Animals alter their behavior in the wake of the changing environment. The results are usually easy to see.

It wasn't until late 1980s that biologists began realize that natural selection was in play. The key is the fact that different traits can confer the ability to survive at different rates and reproduction, and can be passed on from generation to generation.

In the past, if one particular allele - the genetic sequence that controls coloration - was present in a group of interbreeding organisms, it might quickly become more common than all other alleles. As time passes, that could mean the number of black moths within 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 the species, like 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 are taken on a regular basis, and over 50,000 generations have now passed.

Lenski's research has demonstrated that mutations can alter the rate at which change occurs and the effectiveness of a population's reproduction. It also proves that evolution takes time--a fact that many are unable to accept.

Microevolution is also evident in the fact that mosquito genes for pesticide resistance are more prevalent in populations that have used insecticides. This is due to pesticides causing an exclusive pressure that favors individuals who have resistant genotypes.

The rapid pace at which evolution can take place has led to a growing awareness of its significance in a world shaped by human activities, including climate changes, pollution and the loss of habitats that hinder many species from adjusting. Understanding evolution will help us make better choices about the future of our planet, as well as the life of its inhabitants.