Georgia K

     Evolutionary processes are understood by many concepts. Natural selection, adaptation, and fitness. Biologists use these concepts to describe evolution. But it is important to note that natural selection does not necessarily lead to an evolutionary change. By definition of the book, Princeton Guide to Evolution, “Natural Selection is the process in which individuals with a particular trait tend to leave more offspring in a next generation than do individuals with a different trait” (Losos, 2013). Those with positive traits will have an increase in reproductive success, while those with negative traits will not. Evolution is described by Darwin, “the study of the transformation of species through time, including both changes that occur within species, as well as the origin of new species” (Losos, 2013). Both natural selection and evolution sound a little similar, but natural selection can occur without leading to evolution. The catch is that only if differences among ...

  Fitness is the level of performance of how well an organism can survive, adapt, and reproduce. Measuring the level of fitness can determine the long-term dynamics of an organism. According to the Princeton Guide to Evolution, some factors that determine fitness are sex, age, traits, spatial structure, relationships, and hierarchies. Fitness is also something that can be passed down from parent to offspring in order to continue the dynamics of success. Other species who are deemed unfit will have a decreased chance of passing down traits because of survival. Fitness, selection, and other forms of adaptation can explain the millions of cases in biology of precision and complexity.   To measure fitness in a natural population, I would look into the phenotype and genotype of the Kansas Black Tailed Jackrabbit-  Lepus californicus.  This means I would look at the observable traits of the rabbit, such as the color of the coat. The coat of a jackrabbit is peppery brown, w...

  Jean Baptiste Lamarck, a French naturalist in 1801, proposed a theory that physical change in organisms during their lifetime would be transmitted to their offspring. An example of this would be a greater development of an organ once there is an increase use, and then would be passed down to offspring. Of course, this type of evolution has its flaws, but some of the concepts align slightly with the real theory of evolution that is known today. One of his ideas was how environmental factors play a big part in change in a species, in order for the species to be able to survive and breed. He got this aspect right because we can see from Darwin’s Galapagos Island finches, that relative beak size would change over time due to environmental factors. When a drought would run through the island, beak size began to increase with time when there were no nuts, seeds, and other food sources available. The finches with the larger beaks survived because they had other food sources they could a...

  It is obvious there are compelling evidence to show that evolution has been or is happening. This can be from microevolution, macroevolution, descent from common ancestors, and how earth and life are old. One of my favorite predictions of Darwin’s idea of descent with modification would be speciation, the idea that lineages split and diverge. As a biology major, I have learned much about speciation and one research that particularly struck my attention was the research done by biologist, Leland H. Hartwell, and his research with yeast and somatic mutations with cancer.   Yeast, or  Saccharomyces cerevisiae,  has been used for thousands of years for baking bread, brewing beer, and all sorts of other things. Surprisingly, it is also very popular when studying genetics and tells us a lot about the fundamental process of life. Yeast is an easy-to-manipulate, unicellular, eukaryotes. Above shows S. cerevisiae under a microscope. Hartwell used  S. cerevisiae , or b...

       The definition for the word “evolution” has a very broad meaning. Evolution can really be applied to anything; plants, animals, bacteria, social behavior, agriculture, human health, medicine, and so much more. In my own words, I would describe evolution as a process for species to adapt or modify into a more complex form. This modification allows for the species to adapt better to their environment. Whether that be a gradual development, or something that happens over centuries, evolution is an ongoing occurrence, in my opinion.     There are many aspects that can explain the reasoning by evolution, which I will go into small detail about a few. The study of fossils, also known as paleontology, provides direct evidence of species from past life and it also shows a descent of organisms with common ancestors. Studying fossils can help explain about extinct as well as current living species today. This can also give scientist a theory on how the modific...