Geologic Timeline Individual Reflection

The first major event in Earths history was the beginning of photosynthesis in cynobacteria. This is important because it increased the oxygen content in the atmosphere which led to the rise of eukaryotes and later plants and animals. Animals cannot survive without enough oxygen so we would not be here if it had not been for this event.

The second major event was the Permian extinction at the end of the Paleozoic Era. It was the largest mass extinction in Earth's history killing 80% of all life. This loss of life was necessary for the explosion of new life that happened afterwards. The absence of many species allowed dinosaurs to occupy the empty niches and start the era of Dinosaurs.

The third important event happened in the tertiary period when birds, mammals and flowering plants began to dominate. This happened when the dinosaurs went extinct after the cretaceous and the evolution of mammals led to the first humans. Without this event humans may not exist or be much different than what we are today.

The scale of Earth's history is incredibly massive. It surprised me looking at the timeline that all the eras and periods we talk about are all in the span of only about a meter. The Earth was barren with little to no life for most of history. When reading about it it seems that all the eras and periods are roughly the same length but looking at it you can see that the Precambrian Era is most of Earth's history.

Humans have had such a great impact on Earth in just a few hundred years. And most of our impact has happened in the last hundred. We are destroying ecosystems that took hundreds of millions of years to evolve in just years. Humans have existed for just a few thousand years, and have done more in a blink than any other species has done in millions of years.

Some questions I have are why did it take so long for life to take off and start evolving? Why did some species go extinct? Where there intelligent species in the past that went extinct? Why did the planet evolve the way it did?

20 Time Project Update

I am still set on the path I  identified in my last blog post. I am on track for working with Mr. Fitzgerald to help him in his garden. I further researched native plants and how to grow them in a greenhouse (Mr. Fitz plans on having a greenhouse built soon). Also, a possible project on building a worm bin may be available for me so I researched that too. Basically, I have been doing a lot of reading and research to learn more about my topic and be prepared when its time for me to take the next step in my project.

Unit 8 Reflection

Unit 8 was about evolution and how and why species evolve. Evolution can be measured as a change in the frequency of an allele in the gene pool. The gene pool is the the total number of genes in a population. One of the main forces that sparks change in the gene pool is natural selection,  the theory that the "winners," or individuals with better traits survive and reproduce to pass their genes on while the individuals with traits that don't help survival die and take their genes with them. We explored this in the Hunger Games Lab. When we tested this, the individuals with traits that helped them pick up food increased in population while the individuals with bad traits nearly died off. The allele frequency was graphed and showed the allele frequency change, showing that evolution was occurring.

The type of natural selection exhibited in this lab was directional selection, where one extreme phenotype, in this case the pincher, was favored so the phenotypes shift towards that. Stabilizing selection is where the average phenotype in the middle are favored and extremes are not. This keeps the population from changing. Disruptive selection is when both extremes are favored and the graph splits in two. This is often the beginning of speciation.

http://www.course-notes.org/biology/topic_notes/33_behavioral_ecology/fecundity_selection

Natural selection is not the only thing that can change allele frequency. Genetic drift is when random acts kill random members of the population, eliminating them from the gene pool. This can be harmful because it lowers genetic variation. Gene flow is movement of alleles between populations, and mutations can also change allele frequency. Sexual selection traits are traits that increase chance of mating but do not help an individual survive.

New species are created in a process called speciation. When a species is reproductively isolated, they begin to drift apart until they are two different species. They become different species in a process called evolution. There is evidence to prove evolution exists. There are certain traits that modern day organisms have that are useless but would have been useful to ancestors. Also, similarities between species point to a common ancestor in the distant past.

Earths vast history is split up into eras, periods, and epochs. Mass extinctions mark the end of many of these. Each time period has different characteristics.

This unit was not a very difficult unit, but the scale of the Earth's timeline is hard to comprehend. Some questions I have are how did unicellular organisms turn into multicellular organisms and then plants and animals. Also how did asexually reproducing organisms evolve and become sexually reproducing.

I have had a chance to be more assertive in the geological timeline project. I have realized that there is a time to be a leader and be slightly more aggressive for the better of the group, but also a time to sit back more passively to better the group. But mostly, I have been assertive by leading with clear logical steps and listening to the ideas of others.

Hunger Games Final Analysis

1. In this lab we simulated generations of a population by having each generation have to get enough food to survive and reproduce.
2. The pincher was the most successful at getting food because it could do it very easily and quickly, leading to survival and reproduction.
3. The population did evolve because the allele frequency changed. The allele frequency was roughly equal in the beginning but by the third generation the A allele only consisted of 3% of the total alleles and the a allele was 97%. This is a drastic change in the allele frequency, and it showed in the phenotypes as most of the populations were pinchers, with few knucklers and no stumpys while the amount of each phenotype was equal in the beginning.
4. The food placement was often random and reproduction usually created a random offspring (given that the traits were present). Sometimes the food was not random and favored some over others. This could affect evolution because it can favor some without the best traits and cause some with the best traits to die to to chance.
5. If the food was smaller it may favor pinchers even more, but if it was large it may favor stumpys instead. If the food source changes or one food source goes down or extinct individuals with certain traits who were not favored before may be favored then.
6. the results may have been different if there was no incomplete dominance. There would be no knucklers, only stumpys and pinchers. At one point in the lab the stumpys went extinct but came back thanks to the knuckers. If they went extinct with no incomplete dominance they wouldn't be able to come back.
7. Evolution is caused by natural selection. Natural selection picks the individuals with the best survival traits to survive and reproduce. By weeding out the bad traits, those soon disappear or become less common while the better traits become more common, changing the population.
8. Individuals often mated with other individuals of the same phenotype, which cause the knucklers and stumpys to stick around. This relates to sexual selection found in nature. To increase chances of survival individuals sometimes cheated to get their food and stole from others. This can also happen in nature.
9. In evolution populations evolve. Natural selection acts on the genotype which affects the phenotype. Natural selection affects what genes are passed from parents to offspring which determines their traits.
10. What are more examples of events or things that could change a population? How have humans affected this process?

20 Time Garden Project Update

Lots has happened in the past few weeks pertaining to my 20 time garden project. My path has been redirected slightly, but in a good way. I talked with Mr. Fitzgerald, a science teacher at Redwood Middle School, about the Redwood school garden. He is in charge and has a lot of ideas on how to make the garden and the campus a better place. I would like to dedicate my 20 time to helping him achieve this. He has ideas on planting native plants around the school to beautify the campus and teach students about the importance of native plants. He also has projects planned for the garden such as a greenhouse and a worm composting bin. I have spent time researching these things to ensure these projects are as successful as they can be. I would like to further research these topics and make a landscape plan for the native plants.

Unit 7 Reflection

This unit was about ecology and some of the harmful effects humans have on the planet. One of the most important concepts in ecology is trophic levels and the food web. This explains how energy moves through an ecosystem and also shows how an ecosystem can collapse. Population is another factor that influences ecosystems. Populations change frequently and are dependent on factors like water, resources, food and space. When the growth of a population levels out, it is said that the species has reached its carrying capacity. Humans have not reached the carrying capacity yet but population growth has slowed down. Limitations of resources are the main limitation for species. To keep resources available, several crucial cycles such as the water cycle, carbon cycle, phosphorous cycle, and nitrogen cycle.



Humans are exploiting these resources and endangering ecosystems and species across the planet. Habitat destruction, climate change, and over exploitation are some of the main reasons the planet is this way. We need to act fast to preserve biodiversity, slow climate change, and reduce the amount of resources we use and pollutants and waste we create. If everyone makes a conscious effort to save the Earth, it will add up for the benefit.

Some questions I have are is it too late? What will happen when we exhaust all the natural resources? How are animals adapting to these changes? What can we do to help?

Our conservation biologist project went pretty well. We worked well as a group to complete the project on time. Everyone finished their share of work so we didn't have to worry. Like all group projects, it could be frustrating at times because you have to compromise and things don't always go as planned.

On the self assessment, I was not surprised with my results. I am fairly assertive but also sometimes passive. In my everyday life I have noticed that I do not always speak up when I probably should. I think if I act assertive like it says in the video, it will definitely make me a more assertive person.

https://www.thinglink.com/scene/732996661223096321

Saratoga High School Garden

In short, 20 time is spending 20% of your time on something you are passionate, in the form of a project or anything else you can think of. It is meant to be creative and self motivated. The essential question I am asking is could there be a garden at Saratoga High. For my project, I am researching, and if possible, I want to see what needs to be done to create a rooftop garden, or any garden, at Saratoga  High. I have always liked gardening, and I know that there are many benefits to having a garden at a school. SHS does not have a garden, so implementing a garden could help many people. My goals are to have either a garden at the school, or have the administration or staff strongly considering a garden by the end of the year. I will measure my progress by researching and answering all of my obstacles and questions that need to be answered to get this built. In the future, I hope to use class time to  figure out logistics involving the garden, and contacting administration in hopes they will support this project.