Natural and Sexual Selection of Vestigial and Wild Type Drosophila Melanogaster

One possible error that may have occurred was that some of the adult flies may have accidentally been left in the vials with their offspring,

Drosophila melanogaster is a small, common fly found near unripe and rotted fruit. It has been in use for over a century to study genetics. Thomas Hunt Morgan was the best biologist studying Drosophila early in the 1900’s. Morgan was the first to discover sex-linkage and genetic recombination, which placed the small fly in the forefront of genetic research. Scientists have used Drosophila for many reasons. For one they are very easy to maintain, breed, anesthetize, and kill with little equipment. They are also very small and it is easy to distinguish males vs females and sexually mature flies and virgins. At lastly, the flies have a very short two week life span. On days 2-7 of their life

The Evolution Lab simulates environmental situations to determine effects on evolution over periods of time. This lab experiments with the evolution of finches on two different islands over 100, 200, and 300 years. By manipulating parameters that influence natural selection, the effects that natural selection have on the evolution process can be studied.

Sexual selection was an idea proposed by Darwin and refers to the process in which males and females attempt to maximize their chances of reproductive success. Within a species there are certain characteristics that make individuals attractive to potential mates. An example of this is in peacocks, female peacocks are attracted to males with long brightly colored tails, even though this makes them easier to be spotted by predators. This characteristic then evolves within the species due to how males with this characteristic have a higher chance of reproductive success and their characteristics being passed on to surviving offspring.

The Avis Papyrus, more commonly known as the Carmel Origami Bird, native to the sparsely spaced Cool Creek Islands, was subject to a study of its evolutionary success. These birds must travel long distances to get between the islands they inhabit in order to survive long enough to produce offspring; meaning that being able to fly long distances aids in their fitness. The development of these beneficial characteristics are possible because of something called natural selection. Natural selection is the gradual process over the course of generations where a species gradually develops and excludes traits and characteristics (Fukuyama, 2004). This is to help increase reproductive success of an organism and increase the animals fitness. The experiment looked at how natural selection led to their evolution and it’s raw data shows evidence that the Origami Birds have met evolutionary success due to natural selection.

The purpose of the lab was to see what color bead bug would survive the longest in the environment. By performing the experiment, natural selection was being tested. Natural selection is when organisms that are most suited to the environment survive and reproduce more successfully. Certain colored bead bugs would survive longer, because they blended in. The bead bugs that are a more prominent color stood out more and were eaten right away. This experiment displays how the population of bead bugs changes over the generations, due to the amount being eaten and the amount of bead bugs that were reproduced.

This experiment involved the testing of pill bugs and whether or not pill bugs prefer fruit over vegetables. The experiment results concluded that the hypothesis was incorrect; that pill bugs do not prefer fruit over vegetables. In the experiment, we observed twenty pill bugs over several five minute intervals. After five minutes, the number of pill bugs near the apple and lettuce were counted, as well as the ones that remained in the center of the container. The experiment was repeated, and the lettuce and apple locations were switched the second time to make sure location was not a factor in the results. In the first thirty-minute experiment, the pill bugs seemed to start off and gradually move toward the lettuce. Near the end of the experiment,

It would be expected that the mutant F1 flies would be heterozygous for the allele responsible for the grounded trait. If two F1 flies were mated, the percentage of flies that would be expected to be wildtype in the F2 generation would be 25% mutants given that the mutant allele (ap) is predicted to be recessive and, leaving 75% to be wildtype (ap+).

METHODS: In this experiment, the instructor provided us with 30 ebony individuals and 20 wild type individuals. In order to get an exact amount of each type, we anesthetized the flies and counted them off by gently using a fine point paint brush. Then all 50 Drosophila were put into a population cage which had a lid that had six holes for the centrifuge tubes. Two food tubes and four clean, empty tubes were added on the first day. Each food tube consisted of half a cup full of food mixed with 6-7 milliliters of water. This was the fly medium. The food should turn blue once the water is added. Each tube was labeled with a number and with the date. Every two to three days we added one more food tube until all 6 tubes contained the fly medium. After all 6 tubes were filled, the following days after we exchanged the first food tube with a new food tube. At the end of the experiment, we fed the flies with a total of 8 food tubes. Then the flies were anesthetized, again. At the end of this four week lab, the number of living ebony and wild

Natural selection is an important component of evolution. Natural selection occurs when some members of a population are better fit for survival and reproduction than the others in that population (Phelan 284-85, 2011). The environment in which organisms live plays a part in natural selection as well. Depending on the conditions of the environment, the organisms may pass down selected traits to their offspring. These selected traits will allow for the next generation to better adapt and survive longer. One example of evolution that has occurred in the past ten years is that of hypolimnas bolina, or the blue moon butterfly. The blue moon butterfly evolved through the process of natural selection in order to survive. The male blue moon

A. The flies in the rural boxes were devoured by its predator (Spalangia), these small wasps, lay eggs into immature fly pupae after hatching, the wasp larvae feeds on the developing fly, killing it. This study suggests that stable flies are vulnerable out in the rural pastures rather than inside the feed lots where

we said goodbye and placed them in the fly morgue. We allowed the F2 larval

Sexual selection can best be described by the definition given by Darwin himself. Sexual selection is “the advantage which certain individuals have over other individuals of the same species solely in respect of reproduction” (Hosken et al, 2011). Sexual selection occurs throughout the animal kingdom, where male frogs dominate through the depth of their croak, and certain peacocks reign superior based on the colour and intricate detail on their tails. They remain superior to their lesser counterparts as they bear more admirable characteristics, from which they are chosen by females of the same species.

Care was taken to not let the immobilised Drosophila drown in the white media until they were flying again.

Morgan’s studies of sex-linked traits in fruit flies led him to suggest that the genes