Does Technology Make Evolution Site Better Or Worse?
The Academy's Evolution Site
The concept of biological evolution is a fundamental concept in biology. The Academies are involved in helping those interested in science to understand evolution theory and how it is permeated across all areas of scientific research.
This site provides a range of tools for teachers, students, and general readers on 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 used in many cultures and spiritual beliefs as a symbol of unity and love. It also has practical applications, such as providing a framework for understanding the history of species and how they respond to changes in the environment.
Early attempts to represent the biological world were founded on categorizing organisms on their metabolic and physical characteristics. These methods depend on the sampling of different parts of organisms, or DNA fragments, have significantly increased the diversity of a tree of Life2. However these trees are mainly made up of eukaryotes. Bacterial diversity is still largely unrepresented3,4.
By avoiding the need for direct experimentation and observation, genetic techniques have made it possible to represent the Tree of Life in a more precise way. We can construct trees by using molecular methods such as the small subunit ribosomal gene.
Despite the massive growth of the Tree of Life through genome sequencing, a large amount of biodiversity remains to be discovered. This is especially relevant to microorganisms that are difficult to cultivate, and are usually found in one sample5. A recent study of all known genomes has produced a rough draft of the Tree of Life, including numerous bacteria and archaea that have not been isolated and whose diversity is poorly understood6.
The expanded Tree of Life can be used to assess the biodiversity of a specific area and determine if specific habitats require special protection. This information can be used in a range of ways, from identifying new treatments to fight disease to enhancing 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 important metabolic functions that could be at risk of anthropogenic changes. While conservation funds are important, the best method to preserve the world's biodiversity is to empower more people in developing countries with the necessary knowledge to act locally and promote conservation.
Phylogeny
A phylogeny (also called an evolutionary tree) shows the relationships between different organisms. Scientists can build a phylogenetic diagram that illustrates the evolutionary relationship of taxonomic groups using molecular data and morphological differences or similarities. The concept of phylogeny is fundamental to understanding biodiversity, evolution and genetics.
A basic phylogenetic tree (see Figure PageIndex 10 Finds the connections between organisms that have similar traits and have evolved from an ancestor that shared traits. These shared traits could be either homologous or analogous. Homologous traits share their underlying evolutionary path while analogous traits appear similar but do not have the same origins. Scientists organize 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 eggs. The clades then join to create a phylogenetic tree to determine the organisms with the closest relationship.
에볼루션 카지노 use DNA or RNA molecular information to create a phylogenetic chart which is more precise and precise. This data is more precise than the morphological data and gives evidence of the evolutionary background of an organism or group. Molecular data allows researchers to determine the number of organisms that share the same ancestor and estimate their evolutionary age.
The phylogenetic relationship can be affected by a variety of factors, including the phenotypic plasticity. This is a type behavior that changes as a result of particular environmental conditions. This can make a trait appear more similar to a species than another and obscure the phylogenetic signals. However, this problem can be reduced by the use of techniques such as cladistics that incorporate a combination of similar and homologous traits into the tree.
In addition, phylogenetics helps determine the duration and speed at which speciation takes place. This information can aid conservation biologists in deciding which species to safeguard from the threat of extinction. Ultimately, it is the preservation of phylogenetic diversity which will create a complete and balanced ecosystem.
Evolutionary Theory
The main idea behind evolution is that organisms acquire different features over time due to their interactions with their environments. Many scientists have proposed theories of evolution, such as the Islamic naturalist Nasir al-Din al-Tusi (1201-274) who believed that an organism could evolve according to its individual needs, the Swedish taxonomist Carolus Linnaeus (1707-1778) who developed the modern taxonomy system that is hierarchical, as well as Jean-Baptiste Lamarck (1844-1829), who suggested that the use or non-use of traits can lead to changes that can be passed on to future generations.
In the 1930s and 1940s, theories from a variety of fields -- including genetics, natural selection and particulate inheritance--came together to form the current synthesis of evolutionary theory which explains how evolution is triggered by the variations of genes within a population, and how those variants change in time as a result of natural selection. This model, 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 discoveries in the field of evolutionary developmental biology have shown that genetic variation can be introduced into a species by mutation, genetic drift, and reshuffling genes during sexual reproduction, and also through the movement of populations. These processes, along with others 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 over time (the expression of that genotype in the individual).
Students can better understand the concept of phylogeny through incorporating evolutionary thinking into all areas of biology. In a study by Grunspan and co. It was found that teaching students about the evidence for evolution boosted their understanding of evolution during an undergraduate biology course. For more information 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
Traditionally, scientists have studied evolution through looking back--analyzing fossils, comparing species, and studying living organisms. Evolution isn't a flims event, but an ongoing process. Bacteria transform and resist antibiotics, viruses evolve and escape new drugs and animals change their behavior in response to the changing environment. The changes that result are often evident.
But it wasn't until the late 1980s that biologists understood that natural selection can be seen in action, as well. The main reason is that different traits confer an individual rate of survival and reproduction, and can be passed down from generation to generation.
In the past when one particular allele--the genetic sequence that defines color in a group of interbreeding organisms, it could quickly become more common than other alleles. In time, this could mean that 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.
It is easier to see evolutionary change when a species, such as bacteria, has a rapid generation turnover. Since 1988 the biologist Richard Lenski has been tracking twelve populations of E. coli that descended from a single strain. samples from each population are taken on a regular basis, and over fifty thousand generations have passed.
Lenski's work has demonstrated that mutations can drastically alter the efficiency with the rate at which a population reproduces, and consequently, the rate at which it changes. It also shows that evolution takes time, something that is difficult for some to accept.
Another example of microevolution is that mosquito genes that are resistant to pesticides show up more often in populations in which insecticides are utilized. This is because pesticides cause a selective pressure which favors individuals who have resistant genotypes.
The speed at which evolution can take place has led to a growing awareness of its significance in a world that is shaped by human activity--including climate changes, pollution and the loss of habitats which prevent many species from adapting. Understanding the evolution process can help you make better decisions about the future of the planet and its inhabitants.