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Sarcopterygians are one of the two classes of osteichthyes (the other being actinopterygians). This group includes all lobed fined fishes and may be divided into the dipnoi and actinistia. There are four characteristics which unite all sarcopterygians. These fish have monobasic paired fins, in which a singular bone articulates the connection to the fishes body. These fins also have a muscular base. Furthermore the teeth of a Sarcopterygians are covered in enamel. The sclerotic ring around the eye of a sarcopterygians is also comprised of at least 4 bones. Interestingly these features can all be found in humans as well. Technically we can be defined as a boney lobe finned fish. The only exception to this is that the sclerotic ring being comprised of 4 or more bones is often reduced or completely absent in mammals.

This course involved a lot of group work and outside class involvement. Most of my classes before did not involve forming groups and all the work was individual and I have had very few research projects. I have improved as a student because I had to significantly improve my study habits in order to do well in this class. I had to work on bettering my study habits and focus on doing a lot of outside class work. I saw improvement in myself as a student throughout this semester in the fact that I improved greatly on the second exam and  I started to understand the material a lot more. Towards the end I was allowing myself time to actually go through class notes and do the readings which is not how I started the semester. I greatly improved my time management skills and I was better able to figure out what work I needed to do during a certain week and I was able to make a plan to effectively get all the work done in. Having to rely on myself to learn a lot of the material improved my skills as a student because I started to be better at finishing assignments ahead of time and I did the readings throughout the weeks instead of ignoring them. I also improved as a team member because I had to not only do well to account for myself, but to account for my partners as well. This meant I did not have the option of slacking. I also used a lot more software this semester that I have never used before such as Raven and JWatcher. Learning how to use these softwares gave me a wider range of professional skills and will also help me in learning how use new software in the future because I know I will have to read manuals and practice in order to properly utilize a new software given to me.

This was the first specified biology class that I have taken that was more in depth than just “evolution” or “ecology”. I had a lot of prior knowledge about evolution and some animal behavior in terms of environment from other biology classes, but I learned a lot more in depth examples of how to apply evolutionary concepts to the roles of animals. I never looked deeply into animal communication before this class but now I notice a lot more animal interactions and I find myself trying to reason certain behaviors that I observe. When I went home throughout this semester I noticed how my cat interacts with us more and that there are certain things he does that will always be indicators of something he wants. When he wants to be fed he will nudge me and meow, so I know he’s hungry. When he wants to be let outside, instead of nudging me he’ll walk around my feet until I follow him to the door. I’ve noticed that there are different signals for different reasons, which is something I did not think about prior to this course. We also recently got a new cat and I’ve noticed that my cat has started to act differently when in the presence of the new cat. Now,  I try to observe behaviors and think of reasons that could explain a certain meow or tail movement and then observe to see if I can reason it. This is a new behavior of mine that I developed from this class because I did not think about my cat having different signals and different ways to communicate before this class. From this class I have become more curious about how animals interact with one another and I observe my pets a lot more than I would have without taking this course.

The family Sphyraenidae contains the barracudas. This family contains only 1 genus and 29 species. Originally barracudas were considering to be in the genus of esox, though it is now in sphyarena. Small barracuda tend to congregate in schools, however when they become large enough the become solitary fishes. Generally these fish get up to 1.5m in length. Barracudas are specialized to be fast start, rather than distance swimmers. Thus, their fins are located more caudally than rostralling. Ciguatera posioning tends to build up in their tissues, and when eaten it may cause the indavudal to become sick. This is passed from microorgansims which small fish eat, and then the barracuda will eat the small fish. Over time bioaccumulation occurs and the posion builds in the barracudas tissue. One hypothesis about why the poison does not effect the fish, but effects a human that eats the fish is that, the posion itself is in a tissue not being broken down (ie: its muscles, unless under starvation conditions). However when eaten, this tissue is broken down, thus releasing the posion.

Like eukaryotic DNA, prokaryotic DNA (plasmids) must segregate during replication. This idea is interesting because of the structural differences between eukaryotic DNA and plasmids. Plasmids are essentially circular pieces of DNA the attach at both ends. A plasmid is generally condensed, similar to how a rubber band twists up. The potential energy stored in the condensed plasmid configuration can be used to propagate certain interactions. Since our eukaryotic cells utilize microtubules in chromosomal segregation, I wonder how microtubules interact with plasmids; their structure is different, so I imagine their segregation is similarly different when compared to eukaryotic DNA.

The aim of this experiment was to test the effects of temperature on spider web production for the species Pholcus phalangioides. We had hypothesized that the warmer the temperature a spider occupied, the denser the web it would create. During this experiment, spiders were placed in 3 environments set at different temperatures. The control enclosure was kept at 19℃, the warm enclosure was kept at 26℃, and a cool enclosure was kept at 11℃. For the control and cool conditions, the spiders were placed in a plastic cup which was enclosed in a Styrofoam box; the cool condition had a layer of ice underneath the plastic cup with a cardboard barrier to achieve the cool temperature. The spiders in the heated condition were kept in plastic cups that were placed under a heat lamp. Two spiders for each condition were observed for four days; the spider web enclosures were weighed on the final day in order to measure spider web production. Following the data collection and analysis, the results indicated denser web production in the warm enclosure compared to cool and control conditions.

For the control and cool conditions, the spiders were placed in a plastic cup which was enclosed in a Styrofoam box; the cool condition had a layer of ice underneath the plastic cup with a cardboard barrier to achieve the cool temperature. The spiders in the heated condition were kept in plastic cups that were placed under a heat lamp. Each condition was monitored over a four-day period to ensure the temperatures were constant. Following the four days, the spider contraptions were weighed to get final measurements of the spider web densities.

The aim of this experiment was to test the effects of temperature on spider web production for the species Pholcus phalangioides. We had hypothesized that the warmer the temperature a spider occupied, the denser the web it would create. During this experiment, spiders were placed in 3 environments set at different temperatures. The control enclosure was kept at 19℃, the warm enclosure was kept at 26℃, and a cool enclosure was kept at 11℃. Two spiders for each condition were observed for four days; the spider web enclosures were weighed on the final day in order to measure spider web production. Following the data collection and analysis, the results indicated denser web production in the warm enclosure compared to cool and control conditions.

Overall, I found this research project highly conclusive regarding the function of the V1 nerve in reed warblers. I admire the team’s strong efforts in keeping this experiment controlled. For example, the scientists did not know which bird population they were analyzing in order to keep the results unbiased. The team also used a sham-surgery in order to prevent the possibility of there being any skewed data due to surgical setbacks in one group of birds. I find this tactic reasonable and necessary to control the variables in this project, but also a bit unethical as the excess surgeries may have been prevented. This article creates a strong foundation for research regarding how exactly birds utilize map information transmitted through the V1 nerve.

In conclusion, this experiment was able to obtain CFU/ml values for one dilution of E.

coli. There were approximately 8.9x104 CFU/ml of E. coli in one ml of the 10-2 dilution. This

number was obtained using The 10-1 dilution produced to many colonies to count, making

obtaining a CFU/ml value impossible. The other dilutions did not produce more than 30 colonies,

possibly due to a mistake in the dilution process. Another explanation for this could be that when

the dilutions were prepared, the aliquots may have had a lower CFU/ml than other aliquots by

random chance. This experiment showed that using viable counts is a reliable and effective way

to count the number of bacteria in an inoculated sample.