Drafts

    I was initially a little apprehensive about writing 6 drafts each week. I understood the purpose of this assignment, to give the students practice writing for the life sciences and help us organize said writing. This seemed like a lot of work though and I was concerned I would not be able to find topics to write about. I also often have difficulty beginning a report, rather than actually finishing it, and so I was concerned I would not know where to start with these drafts. However, as the semester went on I began summarize my notes in draft form. I believe this helped me organize my thoughts better and therefore understand the material better as well. This gave me a lot of practice writing, even if it was not necessarily for any particular report, and I began more comfortable in my writing skill.

Climate change is a global phenomenon that is changing the average environments in which we live. Change effects different regions of the world in different ways and to different extents. In general, Maine is seeing an increase in temperature during all four seasons of the year. Figure F shows the increase in average temperature from 1970 up to 2017. Winter, indicated by the blue line, has seen an increase of above 4°F, this is the biggest warming season. Fall has increased by just under 4 °F and the spring and summer have increased the least, however summer, the season with the smallest increase, has still seen a rise of just under 1°F (Seasonal Warming Trends. 2018). There is a significant trend indicating a change in temperature in the state of Maine. The current average temperature of winter in Caribou is 23.5°F, so an increase of 10°F would result in an average winter above freezing. If this pattern continues with an increase of about .085°F per year, in just over 118 years this increase would be enough to raise the average winter to above freezing. This is significant when considering the annual temperature anomalies in Figure T because this shows the temperatures will only continue to warm. There are significantly more years warmer than average.

If the trend of an increasingly warm winter continues, which is proven by both Figure G and Figure T, then eventually Caribou will not see temperatures below freezing on average. This will have drastic effects on the seasons and the precipitation, more flooding will occur as there is less snow and the length of seasons will change. Warmer temperatures will cause many problems such as drastic changing of ecosystems, so the wildlife currently inhabiting northern Maine will not be suitable for the environment. They will begin to migrate north to follow the cooler weather and wildlife from the south will migrate north to Caribou in order to also follow cooler temperatures. The ecosystems throughout the country will be out of balance and this can have drastic impacts on industry and the ecosystems.

Apart from fin oscillation patterns, medial and paired fish fins help balance torques and generate thrust. These fins can undergo significant deformation during swimming, and are actively regulated for propulsion and maneuvering. Fish are capable of producing these morphological changes because they have independent intrinsic fin musculature. Concerning the vortex patterns produced by shark tails, the data suggests that they may be the result of active control of the shark tail by intrinsic musculature. The results from the skin denticle study indicate that the denticles improve swimming performance, reducing drag forces and possibly increasing thrust.

Chromosome shortening can be life threatening to any organism. If a chromosome shortens every time it gets replicated, vital and important information is going to get deleted. This will eventually lead to terrible birth defects or the cells not being able to function properly. Most likely death will occur. Because of this, there must be a mechanism to prevent shortening from occurring. DNA replication occurs so much to go right and must be very precise. If the alignment is not proper, chromosome shortening will most likely occur or errors will occur in the process. I feel like cells that have an error will be sent to cell death. It now makes sense to me why HIV can be such a deadly virus for humans. The virus infects and alters the DNA. In addition to that, it reverses transcriptase, which makes DNA from RNA templates. This causes a half DNA half RNA double stranded sequence to form, which ultimately leads to a single strand of DNA. A single DNA strand cannot be duplicated properly.

A study on COM motion in three fish species with different morphologies discovered that the surge fluctuated at twice frequency of the tail for eels and sunfish, while the sway resulted at the same frequency as the tail beat. Despite surge oscillations not changing significantly with increasing speed, sway oscillations did increase. Other study using particle image velocimetry discovered that the water flow of fish with homocercal tails produces vortex rings in a linked-chain pattern, while fish with heterocercal tails like sharks produce dual linked-ring vortexes. Regarding the effect of skin denticles on performance, a study discovered that intact shark skin provides 12.3% more speed than membranes with removed denticles. Lastly, a study using robotic models found that small length changes in swimming bodies can alter speed by a factor of three to five times.

The goal of this review was to examine new ways of analyzing fish locomotion. The author explored recent advances in the center of mass (COM) motion in undulatory fish, water flow patterns produced during swimming, the role of skin denticles in performance, and aquatic propulsion studies using robot models.

Fish locomotion involves the transfer of momentum to water, and is accompanied by changes in the shape of the body and surface structures like fins or scales. Despite the great diversity of fish morphologies and swimming patterns, recent advances in research have shed light on the kinematics of swimming. The motion created by fish can be analyzed in a three-dimensional space to study their center of mass and water flow patterns, and robotic models of fish can provide greater experimental control for such purposes.

Caribou has a humid continental climate, DFB, according to the Köppen classification. This means the city experiences large temperature differences throughout the seasons and has very cold winters as well as very hot summers. Precipitation is ample throughout the year as well. The climograph demonstrated in figure 1 shows the range in temperature with a peak in July and a minimum in January. July is the hottest month of the year with an average temperature of 65.6°F and January is the coldest with an average temperature of 8°F. The average temperature range is 57.6°F which a large range compared to southern areas of the country. Precipitation is ample throughout the year, with July being the wettest month on average. February is the driest but still sees a little over 2 inches of precipitation. The city sees and average of 108.7 inches of snow, which is about 50 inches greater than the average snowfall in coastal Maine and 30 inches greater than the southern interior of Maine.

The tetraodontiformes inclueds the puffer fish and its allies. These are commonly called T-Forms. The fish in this order have an intersting dentition in which the maxilla and premaxilla are fused together. They generally graze on reefs and are slow moving fishes. They may even use their large pectoral fins to grab onto the reef and move in fine scale movements. Many of these fish have modified scales erect as the fish inflates with water and act as a defensive mechanism to protect against being preyed upon. The fish may fully inflate in as quick as 4.5 seconds. T-form fishes have a very short vertebral column which makes them completely inflexible. The only movement that occurs is at their tail. Many of these fish have powerful toxins which also protect from being eaten. The T-Forms incldes 2 groups, the puffer fish and trigger fish. However, sometimes the boxfish is also included.