20 Things You Need To Be Educated About Evolution Site

The Academy's Evolution Site

Biological evolution is a central concept in biology. The Academies have been active for a long time in helping people who are interested in science comprehend the concept of evolution and how it permeates all areas of scientific research.

This site provides a range of resources for teachers, students as well as general readers 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 that symbolizes the interconnectedness of all life. It is used in many spiritual traditions and cultures as a symbol of unity and love. It also has important practical applications, such as providing a framework for understanding the history of species and how they react to changing environmental conditions.

Early approaches to depicting the biological world focused on the classification of organisms into distinct categories which were identified by their physical and metabolic characteristics1. 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 the trees are mostly made up of eukaryotes. Bacterial diversity is still largely unrepresented3,4.

Genetic techniques have significantly expanded our ability to represent the Tree of Life by circumventing the requirement for direct observation and experimentation. In particular, molecular methods allow us to build trees using sequenced markers, such as the small subunit of ribosomal RNA gene.

The Tree of Life has been dramatically expanded through genome sequencing. However, there is still much diversity to be discovered. This is especially true for microorganisms that are difficult to cultivate and which are usually only found in a single specimen5. Recent analysis of all genomes has produced an initial draft of a Tree of Life. This includes a wide range of bacteria, archaea and other organisms that haven't yet been isolated, or their diversity is not fully understood6.

The expanded Tree of Life can be used to evaluate the biodiversity of a particular area and determine if certain habitats need special protection. This information can be used in a range of ways, from identifying the most effective remedies to fight diseases to enhancing crops. It is also valuable in conservation efforts. It can aid biologists in identifying areas that are likely to have species that are cryptic, which could have important metabolic functions and be vulnerable to changes caused by humans. Although funding to safeguard biodiversity are vital but the most effective way to ensure the preservation of biodiversity around the world is for more people in developing countries to be empowered with the knowledge to take action locally to encourage conservation from within.

Phylogeny

A phylogeny, also known as an evolutionary tree, illustrates the connections between groups of organisms. Using molecular data as well as morphological similarities and distinctions, or ontogeny (the course of development of an organism), scientists can build a phylogenetic tree which illustrates the evolution of taxonomic categories. The role of phylogeny is crucial in understanding biodiversity, genetics and evolution.

A basic phylogenetic tree (see Figure PageIndex 10 Determines the relationship between organisms that have similar traits and have evolved from a common ancestor. These shared traits can be homologous, or analogous. Homologous traits are the same in their evolutionary paths. Analogous traits may look similar, but they do not have the same ancestry. Scientists combine similar traits into a grouping referred to as a the clade. All members of a clade have a common characteristic, like amniotic egg production. They all evolved from an ancestor who had these eggs. The clades then join to form a phylogenetic branch that can identify organisms that have the closest relationship to.

Scientists utilize DNA or RNA molecular information to build a phylogenetic chart that is more accurate and precise. This information is more precise than the morphological data and provides evidence of the evolution history of an organism or group. The analysis of molecular data can help researchers identify the number of species that have a common ancestor and to estimate their evolutionary age.

The phylogenetic relationships of organisms can be affected by a variety of factors, including phenotypic plasticity a type of behavior that changes in response to specific environmental conditions. This can cause a trait to appear more like a species another, clouding the phylogenetic signal. However, this problem can be solved through the use of methods such as cladistics which combine similar and homologous traits into the tree.

In addition, phylogenetics can help predict the length and 에볼루션 무료체험 speed of speciation. This information can assist conservation biologists in making choices about which species to save from extinction. In the end, it's the preservation of phylogenetic diversity which will lead to an ecologically balanced and complete ecosystem.

Evolutionary Theory

The main idea behind evolution is that organisms change over time as a result of their interactions with their environment. Many scientists have developed theories of evolution, including the Islamic naturalist Nasir al-Din al-Tusi (1201-274), 에볼루션 바카라사이트 who believed that a living thing would evolve according to its individual needs, the Swedish taxonomist Carolus Linnaeus (1707-1778), who created the modern hierarchical taxonomy as well as Jean-Baptiste Lamarck (1844-1829), who suggested that the use or non-use of traits can cause changes that can be passed on to future generations.

In the 1930s and 1940s, ideas from a variety of fields -- including genetics, natural selection, and 무료 에볼루션 particulate inheritance -- came together to form the current evolutionary theory which explains how evolution happens through the variations of genes within a population and how those variants change in time due to natural selection. This model, known as genetic drift or mutation, gene flow, and sexual selection, is a cornerstone of modern evolutionary biology and can be mathematically explained.

Recent discoveries in evolutionary developmental biology have shown how variation can be introduced to a species through genetic drift, 무료 에볼루션 mutations and reshuffling of genes during sexual reproduction and migration between populations. These processes, in conjunction with others, such as the directional selection process and the erosion of genes (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 aspects of biology education can increase students' understanding of phylogeny as well as evolution. A recent study conducted by Grunspan and colleagues, for example revealed that teaching students about the evidence for evolution helped students accept the concept of evolution in a college biology class. For more details on how to teach evolution read The Evolutionary Potency in All Areas of Biology or Thinking Evolutionarily A Framework for Infusing Evolution into Life Sciences Education.

Evolution in Action

Scientists have studied evolution through looking back in the past, analyzing fossils and 에볼루션 무료체험 comparing species. They also observe living organisms. However, evolution isn't something that happened in the past. It's an ongoing process taking place today. Bacteria transform and resist antibiotics, viruses reinvent themselves and escape new drugs and animals change their behavior to a changing planet. The changes that occur are often apparent.

However, it wasn't until late 1980s that biologists realized that natural selection can be observed in action as well. The key to this is that different traits confer an individual rate of survival and reproduction, and can be passed down from one generation to another.

In the past, when one particular allele, the genetic sequence that determines coloration--appeared in a group of interbreeding organisms, it could quickly become more common than all other alleles. Over time, this would mean that the number of moths sporting black pigmentation may increase. The same is true for 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 rapid generation turnover. Since 1988, Richard Lenski, a biologist, has been tracking twelve populations of E.coli that descend from a single strain. Samples of each population have been collected regularly, and more than 50,000 generations of E.coli have passed.

Lenski's work has demonstrated that a mutation can dramatically alter the speed at which a population reproduces--and so the rate at which it evolves. It also demonstrates that evolution takes time, a fact that is hard for some to accept.

Another example of microevolution is how mosquito genes for resistance to pesticides appear more frequently in populations where insecticides are employed. This is because pesticides cause a selective pressure which favors those with resistant genotypes.

The rapid pace at which evolution takes place has led to a growing 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 adapting. Understanding the evolution process can help us make better choices about the future of our planet as well as the lives of its inhabitants.