• 목록
• 답변
• 글쓰기
• 게시판 리스트 옵션
  • 수정
  • 삭제

The Academy's Evolution Site

Biology is one of the most central concepts in biology. The Academies have long been involved in helping people who are interested in science comprehend the concept of evolution and how it influences all areas of scientific research.

This site provides a range of sources for students, teachers as well as general readers about evolution. It includes important video clips from NOVA and WGBH's science programs on DVD.

Tree of Life

The Tree of Life, an ancient symbol, represents the interconnectedness of all life. It is a symbol of love and harmony in a variety of cultures. It also has practical applications, such as providing a framework for understanding the history of species and how they respond to changes in environmental conditions.

Early attempts to represent the world of biology were based on categorizing organisms based on their physical and metabolic characteristics. These methods, based on sampling of different parts of living organisms or on small fragments of their DNA significantly expanded the diversity that could be included in the tree of life2. These trees are mostly populated of eukaryotes, while the diversity of bacterial species is greatly underrepresented3,4.

By avoiding the necessity for direct observation and experimentation, genetic techniques have made it possible to depict the Tree of Life in a much more accurate way. Particularly, molecular techniques allow us to construct trees using sequenced markers, such as the small subunit ribosomal RNA gene.

Despite the massive growth of the Tree of Life through genome sequencing, much biodiversity still awaits discovery. This is particularly true of microorganisms, which are difficult to cultivate and are typically only found in a single specimen5. A recent analysis of all genomes that are known has produced a rough draft of the Tree of Life, including a large number of archaea and bacteria that have not been isolated, and which are not well understood.

The expanded Tree of Life can be used to evaluate the biodiversity of a specific region and determine if certain habitats need special protection. The information can be used in a range of ways, from identifying new remedies to fight diseases to enhancing the quality of crops. This information is also valuable to conservation efforts. It can help biologists identify the areas that are most likely to contain cryptic species that could have significant metabolic functions that could be at risk of anthropogenic changes. While funds to protect biodiversity are essential, the best way to conserve the world's biodiversity is to empower more people in developing nations with the knowledge they need to take action locally and encourage conservation.

Phylogeny

A phylogeny is also known as an evolutionary tree, reveals the connections between various groups of organisms. Scientists can build an phylogenetic chart which shows the evolutionary relationships between taxonomic categories using molecular information and morphological similarities or differences. The phylogeny of a tree plays an important role in understanding biodiversity, genetics and evolution.

A basic phylogenetic Tree (see Figure PageIndex 10 Identifies the relationships between organisms that have similar traits and have evolved from an ancestor that shared traits. These shared traits are either analogous or homologous. Homologous traits are similar in their evolutionary paths. Analogous traits may look like they are however they do not share the same origins. Scientists combine similar traits into a grouping known as a the clade. All organisms in a group share a characteristic, like amniotic egg production. They all derived from an ancestor with these eggs. A phylogenetic tree can be constructed by connecting clades to identify the organisms that are most closely related to each other.

For a more precise and accurate phylogenetic tree scientists rely on molecular information from DNA or RNA to determine the connections between organisms. This information is more precise and gives evidence of the evolutionary history of an organism. The analysis of molecular data can help researchers determine the number of organisms that share a common ancestor and to estimate their evolutionary age.

The phylogenetic relationships between organisms are influenced by many factors, including phenotypic plasticity an aspect of behavior that alters in response to specific environmental conditions. This can cause a trait to appear more like a species another, obscuring the phylogenetic signal. However, this problem can be solved through the use of methods such as cladistics which incorporate a combination of similar and homologous traits into the tree.

In addition, phylogenetics helps determine the duration and rate at which speciation takes place. This information can assist conservation biologists in making decisions about which species to safeguard from disappearance. In the end, it's the conservation of phylogenetic diversity that will lead to an ecosystem that is complete and balanced.

Evolutionary Theory

The main idea behind evolution is that organisms alter over time because of their interactions with their environment. Many theories of evolution have been developed by a wide range of scientists, including the Islamic naturalist Nasir al-Din al-Tusi (1201-1274) who envisioned an organism developing slowly in accordance with its needs and 에볼루션게이밍 needs, the Swedish botanist Carolus Linnaeus (1707-1778) who designed the modern hierarchical taxonomy, as well as Jean-Baptiste Lamarck (1744-1829) who suggested that use or disuse of traits causes changes that can be passed onto offspring.

In the 1930s and 1940s, ideas from different fields, such as genetics, natural selection and particulate inheritance, 바카라 에볼루션 came together to form a modern evolutionary theory. This defines how evolution happens through the variations in genes within the population, and how these variants alter over time due to natural selection. This model, called genetic drift mutation, gene flow, and sexual selection, is the foundation of current evolutionary biology, and can be mathematically described.

Recent advances in the field of evolutionary developmental biology have demonstrated how variation can be introduced to a species through genetic drift, mutations and reshuffling of genes during sexual reproduction and migration between populations. These processes, along with others, such as the directional selection process and the erosion of genes (changes in frequency of genotypes over time) can lead to evolution. Evolution is defined as changes in the genome over time and 에볼루션게이밍 changes in phenotype (the expression of genotypes in individuals).

Incorporating evolutionary thinking into all areas of biology education can improve students' understanding of phylogeny as well as evolution. A recent study by Grunspan and colleagues, for instance, showed that teaching about the evidence supporting evolution increased students' acceptance of evolution in a college biology course. For more details on how to teach evolution read The Evolutionary Power of Biology in all Areas of Biology or Thinking Evolutionarily A Framework for Integrating Evolution into Life Sciences Education.

Evolution in Action

Scientists have looked at evolution through the past, analyzing fossils and comparing species. They also observe living organisms. Evolution is not a past moment; it is an ongoing process that continues to be observed today. Viruses evolve to stay away from new medications and 에볼루션게이밍 bacteria mutate to resist antibiotics. Animals adapt their behavior because of the changing environment. The resulting changes are often evident.

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

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 prevalent than all other alleles. As time passes, that could mean that 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 an organism, like bacteria, has a high generation turnover. Since 1988, Richard Lenski, a biologist, has tracked twelve populations of E.coli that descend from one strain. Samples from each population have been taken frequently and more than 50,000 generations of E.coli have been observed to have passed.

Lenski's research has demonstrated that mutations can alter the rate at which change occurs and the rate of a population's reproduction. It also shows evolution takes time, a fact that is hard for some to accept.

Another example of microevolution is that mosquito genes that confer resistance to pesticides are more prevalent in areas where insecticides are employed. This is because pesticides cause an exclusive pressure that favors those who have resistant genotypes.

The speed of evolution taking place has led to a growing appreciation of its importance in a world that is shaped by human activities, including climate changes, 에볼루션 바카라 사이트 바카라사이트 - pediascape.Science - pollution and the loss of habitats that hinder many species from adjusting. Understanding evolution can assist you in making better choices about the future of the planet and its inhabitants.