Upper Ordovician Period Lab Report

Introduction:
Over the duration of two lab periods we analyzed Paleozoic fossil from the Upper Ordovician Period of the Paleozoic Era. After an assemblage of fossils were collected from a road cut on Route 1, about one mile south of the junction of Route 1 with Route 52, Franklin CO., Indiana we identified the fossils and made counts of each individual taxon within the different strata’s (lower (oldest), middle, and upper (youngest)). We started of this lab with the null hypothesis: no change in depth over time. After developing the null hypothesis we based our alternative hypothesis off the dependent and independent variable of what we’re testing. The alternate hypothesis: depth changes over time, becoming shallower. The alternate hypothesis

getting shallower, the amount of predators based off the studied taxons will increase. After performing the lab exercise the results showed that the shallower the water gets, the more increasing amounts of predators there are. To test those results we collected samples from each strata level with a one ft^2 wire frame and casted it randomly on the surface of each stratum. All collected samples were loose surface material from that specific area. After collecting the samples from lower (oldest), middle, and upper (youngest) stratums we examined the data. Individually identifying each taxon and how many total taxon’s’ there were in that sample, we created class data. Based off the class data I further examined the predator taxons within each stratum. After identifying the predators who are the Cnidarians and Cephalopods I calculated the amount of predators in each stratum and tested my hypothesis off of those answers. What I expected the outcome to be was what I predicted. The shallower the water gets over time, the more the predators increase. I predicted this outcome because of the photic zone in water. The shallower the water gets, the bigger the photic zone becomes. If the photic zone is increasing in size the more photosynthesis can happen therefore making it so

The taxon I identified, as predators were the horn coral, any other coral from the Cnidarians, and the cephalopods. I calculated the amount of predators in each level by dividing the number of taxon in that invertebrate by the overall number of taxon within that level. The results were: bottom level 0.2, middle level 0.6, and top level 4.8. These results show almost a 7-fold increase between middle level and the upper level. This much of an increase proves my predictions right. The water is getting increasingly shallower and providing a larger photic zone for predators to prosper