Hunger Games Lab Analysis

1. In the Hunger Games lab, we learned about how natural selection acts on beneficial and harmful traits in a population. There were three main phenotypes, stumpys, knucklers, and pinchers. The pinchers had to pick up food with their index and thumb fingers, the knucklers had to pick up food with their knuckles and the stumpys had to pick up food with their wrists. Each of these organisms had to pick up food with their given traits, and thus, it simulated natural selection.

2. The phenotype that was best at capturing were the pinchers, as their method of getting the food was the most effective not only because it was the quickest, but it also ensured that you could pick up multiple pieces of food at once. This is shown in evidence as in each generation, there were always more pinchers that survived to produce offspring than any other species. This was also the reason that the A allele was the prominent allele, as the genotype of pinchers was AA.

3. In this lab experiment, populations evolved in every generation. Never were there the same number of organisms in two consecutive generations, or in any two generations at all. Evolution is a change in allele frequency and since in every year there was a change in allele frequency compared to the previous year, evolution occurred. The graph of the allele frequency is shown below: The blue line represents the frequency of the "A" allele, while the green line represents the frequency of the "a" allele. As you can see, both started out at a similar frequency, but because the "A" was a beneficial trait, while the "a" was a harmful trait, the "A" allele became more common throughout the experiment and was always more common that the "a" allele.

4. In this lab there were many factors that affected the evolution of the population - some were random, while others were not random. Generally, in nature, the distribution of food occurs randomly, however, in this experiment, Mr. Orre distributed the food in different ways every year. This stimulated the randomness of food distribution in nature and thus affected our results. For example, if a pile of food was placed in front of a stumpy, the stumpy would be more likely to succeed in getting more food, thus have a better chance at survival, which leads to an opportunity to reproduce, and thus they would have a chance to pass on their traits, despite their unhelpful traits, solely because of the random food placement in nature. Another factor that affected the evolution of the population was the reproduction and mating between species. This was a factor that was not random and purely chosen, just like it is chosen in nature. In this lab, we stimulated sexual reproduction by choosing a mate and tossing a coin up to see what would be the genotype of the offspring.

5. If the food in the experiment was larger, it would have given the stumpys an advantage when searching for food. Knucklers and pinchers had the advantage in the lab, solely because their method of collecting food was quick and effective because the food could fit in their knucklers and fingers respectively. However, if the food was larger, it might not have been able to be picked up by knucklers or pinchers, and thus would have given the stumpys an advantage, as the wrist can grab larger food amounts. On the other hand, if the food was smaller it would be the complete opposite. The trend in the phenotype and genotype would continue, and it would favor knucklers and pinchers even more than in the status quo. The stumpys struggled to pick up the food in the lab because it was too small, if the food was made smaller, the stumpys might not have survived while the pinchers and knucklers would be able to use their effective collecting method to collect for more. This is like what may happen in nature, as many different organisms might have trouble picking up food in certain sizes. If this is the case, the population will quickly begin to look like the organisms who had the favorable and beneficial traits.

6. If there was not incomplete dominance the results would have varied. If all knucklers had been either pinchers or stumpys the pinchers would have evolved much quicker, and the stumpys would not have been able to rebound from extinction. Because of the knucklers recessive allele, it was possible for them to mate with each other and produce a stumpy, because they had the "a" allele. However, if this did not happen, by the end of the experiment, the only allele in the population would have been pinchers, and the extinction of the stumpys would have happened much quicker.

7. Natural selection is the process when nature chooses which traits of an organism gets passed on to the next generation. If traits are favorable to an organism and help them survive in nature, then those organisms with the favorable traits are more likely to be passed onto the next generation. This leads to the species looking more like the favorable traits as those are the traits that are constantly passed on. Because those are the traits that are passed on, there is a change in the allele frequency of the gene pool, as less and less of the unfavorable traits are being passed onto the next generation, and more and more of the beneficial traits are being passed on. Because of this change in allele frequency, evolution occurs.

8. In the experiment, the stumpys could work amongst themselves, and sometimes with the knucklers to help their population rebound from extinction because of the recessive alleles in knucklers. The stumpys adopted a mindset to band together as a group and succeed, like what we see in nature when herds work together to improve the chance of survival for everyone in the herd. This behavior affected the allele frequency of the population because it allowed for more “a” allele to be passed onto the following generations. We see constantly in nature this happening, as groups of organisms always try to do what's best for their organisms and their species, like what we humans call "family."

9. In evolution, the gene pool and the population evolve. The population evolves by a change in allele frequency, also known as a change in the amount of any allele in the gene pool. This causes the entire population to begin to adopt similar traits that are beneficial for survival. Natural selection acts purely on the phenotype of an organism because the phenotype is the only one that can determine an organism's chance of survival in a population. In nature, the genotype is never seena, and thus cannot affect ad organism's survival. For example, if a chameleon needs an "A" allele to catalogue, both the Aa and AA organisms will have the same chance of survival, because they are both able to camouflage in nature, something that the ones with aa can't do. It did not matter that the Aa organisms had one recessive allege their dominant allele - phenotype, allowed them to survive.

10. I still have some unanswered questions about the food distribution. I understand that in nature food is distributed randomly, but I am extremely intrigued to find out how food is placed and what factors might affect this. Also, are organisms with favorable traits, generally closer to the food supply because of those favorable traits?

Unit 7 Reflection

Unit 7 was all about ecology. Through vodcasts, class discussions and textbook reading, we learned about the main themes and concepts of ecology. We started the units with the main basics of ecology, talking about habitats, niches, biotic and abiotic factors. Habitats include all aspects of the area in which an organism lives, including all abiotic and biotic factors, while niches include all the factors a species needs to survive, stay healthy, and reproduce. Biotic factors are like plants animals, fungi, and bacteria, while abiotic factors are air, temperature, light, soil, etc. We also discussed the levels of ecosystem organization, starting with organisms, going a population, to a community, to an ecosystem. to a biome, then to a biosphere.

Next, we learned about food chains and food webs. Producers, or autotrophs, provide energy for themselves and make their own food from abiotic factors, and consumers, or heterotrophs, get their energy by eating other living or once-living resources. A food chain is a linear network of links that come from a food web. A food web is a diagram that shows energy transfer between different organisms in an ecosystem. The arrows on a food web point to where the energy is going. We also learned about trophic levels, which are levels in a food chain based on what organisms eat. There are five main trophic levels: Quaternary consumer, tertiary consumer, secondary consumer, primary consumer, and primary producer.

We also learned about ecosystem energy, and how the energy that is available in an ecosystem affects the populations at different trophic levels. Interestingly, only 10 percent of the energy that is produced at each level is passed on to the next level. 90 percent of the energy is lost as waste, heat, feces, etc. The way to show this transfer of energy between different trophic levels is through energy pyramids. Energy, which originates from the sun, is passed from producers up the food chain to top-level consumers.

Our next main concept in the unit, and the one that I found the most interesting was ecosystem recycling. We learned about how different cycles contribute to the stability and health of ecosystems. Ecological succession is the sequence of community and ecosystem changes after a disturbance. The order of succession begins with pioneer species after the incident, moving on to intermediate species, then to a climax. There are 4 main nutrient cycles. The water cycle, which consists of the processes of evaporation, transpiration, condensation, precipitation, and movement through surface groundwater. The carbon cycle moves carbon from the atmosphere, through the food web and returns to the atmosphere. Both the nitrogen and phosphorous cycle are also essential to life.

One of the last concepts we learned in our unit was about ecosystem health, and why ecosystem health is extremely important not only for animals and other species but for humans as well. Healthy ecosystems have large populations of tertiary and quaternary consumers and diverse communities of producers and decomposers. Healthy ecosystems also have high biodiversity, includes genetic diversity, species diversity, and ecosystem diversity. In the United States, 25 percent of prescriptions contain substances originally derived from plants, thus overall ecosystem health is important for human life. There are 4 main causes of species loss. Habitat Destruction, Introduced/exotic species, overexploitation, and change in climate.

I really wanted to learn more about the benefits and costs of having great biodiversity on our planet. We had an ecosystem health vodcast about it, and I was extremely intrigued. I found it fascinating that 25 percent of all prescriptions that are made in the United States contain substances that are originally derived from plants. Not only that, I did some research fo my own and found that plants are used in other medical situations as well, and are not just limited to prescriptions. Plants are currently being used to help treat diabetes and cancer, and are likely to be one of the main ingredients if we were to come up with a cancer cure.

Throughout our unit, we did a conservation biologist project, in which we, as groups, set out to solve the major problem treating a particular biome or ecosystem. Our group took on the task of fixing the root causes behind the Great Pacific Garbage Patch. Collaboration is our group was nearly flawless, as each group member not only did his work but helped others whenever he/she could. Working as such an on-task, and effective group, allowed us to finish our work swiftly with little problems. Nearly everything went well, and I learned as long as everyone in the group knows their role and tries their best to execute their part, the group should do great.

Great Pacific Garbage Patch