Charles Darwin: Natural Selection

Evolution is a change in the characteristic of living organism through time. Modern synthesis, one of the greatest intellectual achievements of biology, could explain how mutations and natural selection could produced large-scale evolutionary change. There are 4 mechanisms for evolution to occur; mutation, gene flow, genetic drift and natural selection.
Although, there are a number of misconceptions about evolution; it does not explain the origins of life, it is not progressive, natural selection is not about the survival of the fittest individuals in a population, humans are not currently evolving, it does not make organism better designed nor does it gives organism what they need to survive. This essay will describe further, 3 common misconceptions

The motivation of this lab report is to use Mendel’s Laws of Inheritance to analyze and predict the genotypes and phenotypes of an offspring generation (F2) after knowing the genotypes and phenotypes of the parent generation (F1). The hypothesis for this experiment is that the mode of inheritance for the shaven bristle allele in flies is autosomal recessive in both male and female flies.

The results of this cross was that there were thirty eight wild-type females and thirty five wild-type males. Therefore there were seventy three wild-type flies. There were sixteen no-winged mutant males and eleven no-winged mutant females. Therefore there was a total of twenty seven no-winged flies produced in this cross. The observed phenotypic ratio of wild-type flies and no-winged mutant flies was 2.7:1 (winged: no-winged).The predicted phenotypic ratio if the no-winged mutation was autosomal recessive would be 3:1 (winged: no-winged). The χ2 value obtained for this cross was 0.213. The p value that was obtained for this cross was

Evolutionary biology has always interested me, specifically the mechanisms of natural selection and how species adapt to their environment. It started with my love for animals and nature when I was little. I spent my summers working with horses at a local corral, where I would ride around the surrounding wilderness areas. My favorite part about riding in the mountains was watching the change in plant and animal species as the elevation changed. It never ceased to amaze me how the alpine tree line was always so sudden. Humongous pine trees would give way to the short, shrubby plants of the alpine tundra so uniformly and noticeably. I have always wondered about the environmental conditions that cause species to distribute themselves in

Again the flies were sorted and the first twenty males and twenty females were chosen and their body phenotypes were recorded. The same transfer techniques were used to place the flies in the fresh culture vial. The excess flies were disposed of in the morgue. The allele frequencies and expected heterozygosities at each transfer were

Evolution is the process of biological change by which descendants come to differ from their ancestors. Natural Selection is when an individual with the best trait survive and breed in more population. Larger populations of organisms with the desired traits will then occur and organisms will evolve. The four principles of Natural Selection are variation, over production, adaptation, and descent with modification. Charles Darwin, an English naturalist and geologist saw two major trends within organisms which were variation and adaptation. Variations are differences in individuals’ physical traits compared to other individuals. In the Galapagos Islands Darwin noticed that finches had different beak sizes and shapes. Darwin then concluded that finches with thicker beaks lived in areas where nuts were the main food source and finches with smaller beaks tended to live in areas where insects were the main food source. Adaptation are features that allow an organism to better survive in their environment. There has been many adaptations in animals but one of the best has been living in groups because animals can then “help each other find food, defend against predators and care for their young” (animalpanet, n.d.). Overproduction is when organisms produce more offspring than the environment can support. Darwin stated that all animals over produce since offspring can reach reproduction age and have offspring of their own. For example, “even a slow breeder

Lab 3a had involved 4 F1 generation crosses: a sex-linked cross between white eyed males and heterozygous wild-type female flies (XWY x X+XW), a dihybrid cross between heterozygous wild-type winged flies (Apterous carriers) that have wild-type eyes (but are sepia color carriers (ap+/ap; se+/se x ap+/ap; se+/se) , a monohybrid cross between Apterous and wild-type winged flies (ap/ap x ap+/ap+), and a dihybrid cross between wild type flies that are vestigial winged and sepia trait carriers (vg+/vg; se+/se x vg+/vg; se+/se).

Finally, the definition states that the mechanism that drove all these changes was natural selection. Natural selection is the crucial concept in the theory of evolution and Charles Darwin devotes perhaps the central chapter in his landmark book On the Origin of Species to this notion. Some authors before Darwin discussed the possibilities that life could have evolved, but they approached the issue in a rather philosophical manner without reference to particular facts. What Darwin did was to use the theory of evolution as a powerful way of explaining a

The progeny of this cross were known at the F1 generation. Phenotypes seen in this cross were recorded. Males from this cross were collected. A male that with a different phenotype from the mutation in the mutant flies was selected. (If the mutation in the mutant flies is white-eye, a male without an eye mutation is selected.) The selected male from the F1 generation is then crossed with a virgin female from the parental generation. After which, the phenotypes seen were recorded and used to determine which chromosome the mutation is located on and what the mutation is.

In cross B, a red-eyed female fly was placed into a vial with a white-eyed male fly and a red- eyed male fly for a breeding period of two weeks. At least eight red-eyed females were produced from this cross. These eight females were used to conduct a polymerase chain reaction. Comparing to the control groups, the results show that seven out of eight flies has the Xw+ Xw genotype because all of them had both bands appear on the gel when both alleles were present. This indicates that all of them are heterozygous. They are all red-eye females. Fly 7, however either of the band appear. This means that an error occurred, and one possible error could be not enough DNA were extracted therefore the gel could

Introduction: The Drosophila project was fundamentally conducted to determine potential regulators of the wingless pathway in Drosophila Melanogaster. All the experiments in this project were used to establish two things. Firstly, the location of the transposon insertion and secondly, the effect the genes near the transposon insertion had on the wingless pathway.

Charles Darwin broached the theory of natural selection in his book the Origin of Species, which has been considered the basis of evolutionary biology to this day. Natural selection is when populations of a species evolve over the course of many generations. Darwin believed that species were not created separately, but instead, species were derived from one another. In other words, the evolution of species creates many variations among creatures, and this is because all of those species came from a common ancestor, and characteristics changed to increase the species chance of survival.

Many scientists in the past, such as Aristotle and Plato, believed that there were no changes in populations; however, other scientists, such as Darwin and Wallace, arose and argued that species inherit heritable traits from common ancestors and environmental forces drives out certain heritable traits that makes the species better suited to survive or be more “fit” for that environment. Therefore, species do change over a period of time and they were able to support their theory by showing that evolution does occur. There were four basic mechanisms of evolution in their theory: mutation, migration, genetic drift, and natural selection. Natural selection is the gradual process by which heritable traits that makes it more

Biological evolution is the name for the changes in gene frequency in a population of a species from generation to generation. Evolution offers explanation to why species genetically change over years and the diversity of life on Earth. Although it is generally accepted by the scientific community, Charles Darwin’s theory of evolution has been studied and debated for several decades. In 1859, Darwin published On The Origin of Species, which introduced the idea of evolutionary thought which he supported with evidence of one type of evolutionary mechanism, natural selection. Some of the main mechanisms of evolution are natural selection, mutation, and genetic drift. The idea that all life on Earth shares a common ancestor has been around for

Charles Darwin theory of evolution contains two parts. The first part “Evolution Occurs” meaning organisms change over time in heritable physical or behavioral traits and life on earth has changed as people change from ancestors in the past. Second part “Evolution Occurs by Natural Selection” natural selection is the process in which living things with beneficial traits produce more off spring than others which results in changes that allow an organism to better adapt to its environment can help it survive over time. All life on earth is connected and related to each other and diversity of life came from modifications in populations in natural selectin. Natural selection can also be described as survival of the fittest in which the fittest is the ability to survive and reproduce. Most people believe that the species were created at the same time and remained unchanged after. Darwins ideas of evolution came before scientist knew about DNA it started on his voyage in 1831 when he was 22 years old he went on a scientific trip on a ship called HMS Beagle. He was the naturalist on the trip meaning he was supposed to observe and collect particles of dirt, rocks, animals, plants, and fossils. He was interested by his the nature he spent 3/5 years exploring nature on islands and contents. When Darwin returned he had become famous as a naturalist because a former teacher published Darwins observations.