Learn To Communicate Evolution Site To Your Boss

The Academy's Evolution Site

Biological evolution is one of the most fundamental concepts in biology. The Academies have long been involved in helping those interested in science understand the concept of evolution and how it influences all areas of scientific research.

This site provides a range of sources for teachers, students and general readers of evolution. It includes important video clips from NOVA and the WGBH-produced 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 in many cultures. It also has important practical applications, like providing a framework to understand the history of species and how they respond to changes in the environment.

The first attempts at depicting the world of biology focused on categorizing organisms into distinct categories which had been identified by their physical and metabolic characteristics1. These methods, which are based on the sampling of different parts of organisms or short fragments of DNA have greatly increased the diversity of a Tree of Life2. However, these trees are largely composed of eukaryotes; bacterial diversity is not represented in a large way3,4.

Genetic techniques have greatly broadened our ability to depict the Tree of Life by circumventing the need for direct observation and experimentation. Particularly, molecular techniques enable us to create trees by using sequenced markers such as the small subunit ribosomal gene.

Despite the massive growth of the Tree of Life through genome sequencing, a large amount of biodiversity awaits discovery. This is especially true of microorganisms, which are difficult to cultivate and are usually only present in a single sample5. A recent analysis of all genomes resulted in an initial draft of the Tree of Life. This includes a wide range of bacteria, archaea and other organisms that have not yet been isolated, or their diversity is not well understood6.

The expanded Tree of Life can be used to determine the diversity of a specific region and determine if certain habitats need special protection. This information can be utilized in a range of ways, from identifying the most effective medicines to combating disease to enhancing the quality of crop yields. This information is also extremely useful to conservation efforts. It can help biologists identify those areas that are most likely contain cryptic species with potentially significant metabolic functions that could be at risk of anthropogenic changes. While conservation funds are important, the most effective method to protect the world's biodiversity is to empower 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, illustrates the connections between various groups of organisms. Using molecular data similarities and differences in morphology or ontogeny (the process of the development of an organism) scientists can construct an phylogenetic tree that demonstrates the evolutionary relationship between taxonomic categories. Phylogeny is crucial in understanding the evolution of biodiversity, evolution and genetics.

A basic phylogenetic Tree (see Figure PageIndex 10 ) identifies the relationships between organisms that share similar traits that evolved from common ancestral. These shared traits could be either analogous or homologous. Homologous characteristics are identical in their evolutionary paths. Analogous traits may look like they are but they don't have the same ancestry. Scientists group similar traits together into a grouping known as a Clade. For instance, all the organisms that make up a clade have the characteristic of having amniotic egg and evolved from a common ancestor who had eggs. The clades are then connected to form a phylogenetic branch that can determine which organisms have the closest relationship.

Scientists utilize molecular DNA or RNA data to build a phylogenetic chart that is more accurate and precise. This information is more precise and provides evidence of the evolution history of an organism. Researchers can use Molecular Data to estimate the age of evolution of living organisms and discover the number of organisms that have an ancestor common to all.

The phylogenetic relationships between organisms are influenced by many factors including phenotypic plasticity, a kind of behavior that changes in response to specific environmental conditions. This can cause a trait to appear more similar to one species than to the other which can obscure the phylogenetic signal. However, this problem can be solved through the use of methods such as cladistics that combine analogous and homologous features into the tree.

Additionally, phylogenetics aids determine the duration and speed of speciation. This information can assist conservation biologists decide which species they should protect from extinction. Ultimately, it is the preservation of phylogenetic diversity which will result in an ecosystem that is complete and balanced.

Evolutionary Theory

The fundamental concept in evolution is that organisms alter over time because of their interactions with their environment. A variety of theories about evolution have been proposed 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 gradually according to its needs as well as 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 can be passed on to the offspring.

In the 1930s and 1940s, ideas from various fields, including genetics, natural selection, and particulate inheritance -- came together to create the modern evolutionary theory synthesis which explains how evolution is triggered by the variations of genes within a population and how those variations change over time due to natural selection. This model, known as genetic drift mutation, gene flow, and sexual selection, is a cornerstone of the current evolutionary biology and 에볼루션 바카라 체험사이트 (visit our website) can be mathematically explained.

Recent discoveries in the field of evolutionary developmental biology have demonstrated that variation can be introduced into a species by mutation, genetic drift, and reshuffling genes during sexual reproduction, and also through migration between populations. These processes, along with others like directional selection and genetic erosion (changes in the frequency of the genotype over time), can lead to evolution which is defined by change in the genome of the species over time, and 에볼루션 무료체험 the change in phenotype as time passes (the expression of that genotype in the individual).

Incorporating evolutionary thinking into all aspects of biology education can increase students' understanding of phylogeny and evolutionary. A recent study conducted by Grunspan and colleagues, for example, showed that teaching about the evidence for evolution helped students accept the concept of evolution in a college-level biology course. 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 in 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. Evolution is not a distant event, but an ongoing process. Viruses reinvent themselves to avoid new drugs and bacteria evolve to resist antibiotics. Animals alter their behavior 에볼루션 바카라 as a result of a changing environment. The results are usually easy to see.

However, it wasn't until late 1980s that biologists understood that natural selection can be observed in action as well. The key is that different characteristics result in different rates of survival and reproduction (differential fitness), and can be passed from one generation to the next.

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

It is easier to track evolution when an organism, like bacteria, has a high generation turnover. Since 1988 biologist Richard Lenski has been tracking twelve populations of E. bacteria that descend from a single strain; samples of each are taken every day, and over 500.000 generations have passed.

Lenski's research has revealed that mutations can alter the rate at which change occurs and the efficiency at which a population reproduces. It also shows that evolution is slow-moving, a fact that some people find hard to accept.

Another example of microevolution is how mosquito genes that confer resistance to pesticides show up more often in areas where insecticides are employed. This is due to pesticides causing a selective pressure which favors individuals who have resistant genotypes.

The rapid pace of evolution taking place has led to a growing recognition of its importance in a world that is shaped by human activity, including climate change, pollution and the loss of habitats which prevent the species from adapting. Understanding evolution will assist you in making better choices about the future of our planet and its inhabitants.