Examples of Evolution
Evolution is often mistakenly considered a dead science, one that has not changed since Darwin's time and has no impact on modern life. In fact, evolutionary theory is a lively field of innovative research which is constantly generating novel results. It also has practical applications in modern society. From agriculture to medicine, our understanding of the biological world and our interection with it is based on evolutionary theory. Improvements in crop production or health care are often based on recent research in evolutionary biology. The examples compiled here may be used to engage students in thinking about evolution in new ways.
The following activity is designed to help students find their own examples of evolution in the popular media and in their day to day lives. Assign one topic to each group of two to three students. Have the students look for recent media coverage of the topic focusing on the role of evolutionary biology. Students may prepare a brief presentation for the class, or write up their results. Students should address the following questions:
- How does evolution play a role in this issue?
- Does this example demonstrate natural selection? If so, what are the selective pressures? If not, what is the force driving evolution?
- What role do variation and heritability play in this example, if any?
- How is this topic relevant in your life?
Medical applications of evolution are possibly the most exciting aspect of modern evolutionary research. From determining the molecular basis of disease through developing treatments and cures, researchers rely on the basic principles of evolutionary theory. Meanwhile, the research itself provides new insight into evolutionary processes.
The Human Genome Project is possible and useful because of evolution. All organisms share the basic molecular heredity system of DNA and RNA. Laboratory methods and tools, such as sequencing, provide information from any cell type from bacteria to mammals. The resulting information can be used to study human physiology, health and disease. Although the majority of medical research will be conducted in other organisms such as dogs and primates, this research will apply to humans because we share many physiological pathways due to our evolutionary relationships. Downloadable curriculum materials on the Human Genome Project is available free of charge including DOE-supported Curriculum Modules from BSCS for high school teachers and students, and NIH Curriculum Supplement Series for High School Grades 9-12. Publications, posters, presentations and other materials are available as well.
Examples of Evolution
This list of 15 great examples of recent evolutionary work was published by Nature in January, 2009, in honor of Darwin's 200th birthday and the 150th anniversary of the publication of The Origin of Species.
This list of improtant evolutionary research stories was published by Wired in January, 2009.
From The New Scientist
Human diseases are excellent examples of evolution. Pathogens must evolve rapidly to avoid the human immune response and medical interventions, such as drugs. Because bacterial and viral pathogens have short, and generally quick, life cycles, evolution can be observed in a few days or months. On the opposite side of this equation, some human mutations appear to provide resistance to pathogens, explaining the persistence of these mutations in the human population.
Natural selection works on individuals within a population, with the end result that a variation that provides benefit to the individual will become more prevalent in the population. Natural selection is one variable in evolution, but it is not the only type of selection. Other types of selection include artificial, sexual and kin selection. These selective pressures result in adaptions - particular lifestyles or body plans that provide an advantage in a specific environment.