Why We Do We Love Evolution Site (And You Should Too!)

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 concept of evolution and how it affects every area of scientific inquiry.

This site offers a variety of sources for students, teachers as well as general readers about evolution. It includes key video clips from NOVA and the WGBH-produced science programs on DVD.

Tree of Life

The Tree of Life is an ancient symbol of the interconnectedness of all life. It appears in many cultures and spiritual beliefs as an emblem of unity and love. It has many practical applications as well, such as providing a framework to understand the history of species, and how they respond to changes in environmental conditions.

The first attempts to depict the biological world were founded on categorizing organisms on their metabolic and physical characteristics. These methods, which relied on the sampling of different parts of living organisms, or small fragments of their DNA significantly increased the variety that could be included in the tree of life2. These trees are mostly populated of eukaryotes, while bacteria are largely underrepresented3,4.

By avoiding the need for direct experimentation and observation, genetic techniques have enabled us to represent the Tree of Life in a more precise way. Particularly, molecular techniques allow us to construct trees using sequenced markers such as the small subunit ribosomal gene.

Despite the massive expansion of the Tree of Life through genome sequencing, a lot of biodiversity remains to be discovered. This is particularly true for microorganisms that are difficult to cultivate and are usually only present in a single specimen5. Recent analysis of all genomes resulted in a rough draft of the Tree of Life. This includes a wide range of archaea, bacteria, and other organisms that have not yet been isolated or the diversity of which is not thoroughly understood6.

The expanded Tree of Life can be used to determine the diversity of a particular area and determine if specific habitats require special protection. This information can be utilized in a variety of ways, from identifying new medicines to combating disease to enhancing the quality of crops. This information is also extremely useful to conservation efforts. It can help biologists identify the areas that are most likely to contain cryptic species with potentially important metabolic functions that could be vulnerable to anthropogenic change. Although funds to protect biodiversity are essential however, the most effective method to ensure the preservation of biodiversity around the world is for more people living in developing countries to be equipped with the knowledge to act locally in order to promote conservation from within.

Phylogeny

A phylogeny (also called an evolutionary tree) shows the relationships between different organisms. Scientists can build a phylogenetic chart that shows the evolution of taxonomic categories using molecular information and morphological differences or similarities. Phylogeny is essential in understanding evolution, biodiversity and genetics.

에볼루션 바카라 체험  (see Figure PageIndex 10 Finds the connections between organisms that have similar traits and evolved from an ancestor that shared traits. These shared traits may be analogous, or homologous. Homologous characteristics are identical in terms of their evolutionary journey. Analogous traits may look similar, but they do not share the same origins. Scientists combine similar traits into a grouping known as a Clade. Every organism in a group share a characteristic, like amniotic egg production. They all derived from an ancestor with these eggs. The clades are then linked to form a phylogenetic branch that can determine the organisms with 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 establish the relationships between organisms. This information is more precise and provides evidence of the evolution of an organism. Molecular data allows researchers to identify the number of organisms that share the same ancestor and estimate their evolutionary age.

Phylogenetic relationships can be affected by a number of factors such as the phenotypic plasticity. This is a type of behaviour that can change as a result of unique environmental conditions. This can cause a characteristic to appear more similar to one species than another, obscuring the phylogenetic signal. This problem can be mitigated by using cladistics, which is a a combination of homologous and analogous traits in the tree.

Additionally, phylogenetics can help predict the length and speed of speciation. This information can help conservation biologists make decisions about the species they should safeguard from the threat of extinction. In the end, it is the preservation of phylogenetic diversity that will result in an ecosystem that is complete and balanced.

Evolutionary Theory

The fundamental concept of evolution is that organisms develop various characteristics over time as a result of their interactions with their surroundings. Many scientists have proposed theories of evolution, including the Islamic naturalist Nasir al-Din al-Tusi (1201-274), who believed that an organism could evolve according to its individual requirements as well as the Swedish taxonomist Carolus Linnaeus (1707-1778) who conceived the modern hierarchical system of taxonomy, as well as Jean-Baptiste Lamarck (1844-1829), who suggested that the use or absence of traits can lead to changes that can be passed on to future generations.

In the 1930s and 1940s, ideas from different fields, such as natural selection, genetics & particulate inheritance, merged to create a modern theorizing of evolution. This defines how evolution happens through the variation of genes in the population, and how these variants alter over time due to natural selection. This model, which incorporates mutations, genetic drift as well as gene flow and sexual selection can be mathematically described.

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

Students can gain a better understanding of the concept of phylogeny by using evolutionary thinking throughout all aspects of biology. In a study 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 information on how to teach about evolution, 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 studied evolution through looking back in the past, analyzing fossils and comparing species. They also study living organisms. But evolution isn't a thing that occurred in the past; it's an ongoing process, that is taking place in the present. Viruses evolve to stay away from new medications and bacteria mutate to resist antibiotics. Animals adapt their behavior as a result of the changing environment. The resulting changes are often easy to see.

It wasn't until late 1980s that biologists began to realize that natural selection was in play. The key is that various traits have different rates of survival and reproduction (differential fitness) and are transferred from one generation to the next.

In the past, if an allele - the genetic sequence that determines color - appeared in a population of organisms that interbred, it could be more common than any other allele. As time passes, that could mean the number of black moths in a particular population could rise. 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 species has a fast generation turnover such as bacteria. 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 been observed.

Lenski's work has shown that mutations can alter the rate of change and the effectiveness at which a population reproduces. It also demonstrates that evolution takes time--a fact that some people find difficult to accept.

Microevolution can also be seen in the fact that mosquito genes that confer resistance to pesticides are more prevalent in areas where insecticides are used. This is because pesticides cause an exclusive pressure that favors those with 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 change, pollution and the loss of habitats that prevent many species from adapting. Understanding the evolution process will help us make better decisions regarding the future of our planet as well as the lives of its inhabitants.