User:Corina C. Velazco/Notebook/Biology 210 at AU

Biological Life at AU: Lab 1 on January 15, 2015

Purpose: To observe evolution through natural selection, an ecosystem, also known as a transect, at American University will be observed and analyzed. The biotic and abiotic components will be observed and then a sample from the assigned transect will be taken to examine it through the first several weeks of the semester. This is done to study the interactions that occur in a specific niche and see all the different species that live there.

Materials and Methods: First, the TA gave each student a number to have groups of three assigned to each transect. Once given the map, my group went to the transect and observed, analyzed and took the sample with a 50mL conical tube-- 50% of the soil from the transect and the other 50% consisted of moss, grass, berries and leaves. Then back in the lab a Hay Infusion Culture was made by mixing 10 grams of the sample gathered from the transect with 500mLs of deerpark water (that way there were no pollutants), and 0.1 grams of fried milk. This mixture was covered with a lid and mixed for 10 seconds and then the jar was placed in the back of the lab without the lid.

Data and Observations: The 20 by 20 meter transect that was assigned is located on the North side of campus on the side where Hughes Hall and McDowell Hall are adjacent to each other (labeled #2). Its biotic components consisted of trees, moss, bushes, grass and berries. Its abiotic, or nonliving, components consisted of rocks, occasional shade from the Hughes Hall building, benches, soil and snow.

Conclusions and Future Directions: The biotic and abiotic components in the transect affect the population living in it. By observing the niche, will help identify and learn about the species in that specific niche. The Hay Infusion Culture will be observed the following week and different species will be observed. This provides an idea of how an ecosystem provides a habitat to a diverse amount of species and also it further helps us understand the many life forms caused by evolution.

CV

1.27.15 Good first entry. Nice structure and layout. Good pictures. SK