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The first experiment, done in the 1950s by the German, Gustav Kramer,  suggested that birds use the sun for directional positioning. The birds were housed in a circular cage that allowed them to see the sun. During migrating season,  they would face Northeast at all times, as if they were preparing for migration. However, on cloudy days they would not have any inclination towards any direction. Similar results were also observed in pigeons that were exposed to varied climates and asked to return to their homes. The birds in clear weather excelled where as the subjects in poorer conditions were unsuccessful or less efficient.  Of note, these birds were observed correcting for the sun’s position,  a technique that was noted to be similar to telling time.  This phenenomenon, dubbed the sun-arc hypothesis, was supported by an experiment where a lightbulb was substituted for the sun and the birds naturally corrected in anticipation of this pseudo-sun setting.

    In Spring 2018, as part of the Writing in Biology course at the University for Massachusetts, Amherst a methods project was carried out. The methods section in a piece of scientific writing is an important aspect of an experiment because it illustrates to other prospering scientists what they need to follow in order to obtain the same results. For this project I choose Euphorbia pulcherrima euphorbiaceae, which is a plant found in Mexico and Guatemala.  

In any kind of experiment carried out an important aspect is the methods section. This impact whether your results are valid and can be carried out by other colleagues. For this experiment two photos of the plant species, Euphorbia pulcherrima euphorbiaceae were obtained. This plant is situated in one of the multiple Morrill Greenhouses in the University of Massachusetts, Amherst campus. A multi-panel figure was created to illustrate the plant species.  One of the photos taken was a close-up of the species while the other was a photograph of the plant species as a whole. A world map with the countries Mexico and Guatemala colored in was included as well. This depicted where the plant was indigenous to. Methods produced at the end exemplified how the multi-panel figure was composed and how the photos were obtained. It was then shared with another individual and at the end both resulting multi-panels were compared. Differences were seen in the resolutions of each photo and as well as scaling. The differences were evident and explained. 

Another prominent example of recent evolution resides within the ability to drink and digest milk. Most human adults are incapable of digesting lactose and therefore milk. Babies are capable of drinking milk due to a gene that codes for lactase, which breaks down lactose. In people who are lactose intolerant, the gene essentially switches off after weaning. However, a mutation known as lactase persistence arose in recent human history that allowed lactase to be produced into adulthood. This trait likely provided a selective advantage to individuals with access to domesticated dairy animals, who consumed the unfermented milk. “Analysis based on the conservation of lactase gene haplotypes indicates a recent origin and high selection coefficients for lactose persistence, although it has not been possible to say whether early Neolithic European populations were lactase persistent… (J. Burger et al., 2006)”

    I obtained two photos of the Hibiscus rosa-sinensis Malvaceae, commonly known as the “Snow Queen,” from the Morrill Greenhouses at 12-1 pm (Hibiscus rosa-sinensis). The first photo I obtained was a detailed close up of the flower, while the second photo was a photo that included detail of the plant as a whole. I also created a map that showed the flower originated in East Asia (Hibiscus rosa-sinensis - L).  I created one multi paneled figure with the two photos and the map I created.  I then gave my methods to a classmate to obtain similar photos that I had taken, and for them to create their own multi paneled figure by following what I had did. The results showed that the figure produced by my classmate was different than the figure I had produced. The panel produced by my classmate was structured different as Figure 2A was the close up photo and Figure 2B was the full plant, while Figure 1A was the full plant and Figure 1B was the close up. Figure 2C highlighted two more countries than Figure 1C. The photos in Figure 2 were taken at different angles than Figure 1. Figure 1 had more spaces in between the photos than Figure 2. Factors that lead to the differences between the figures were: different programs to put the separate photos together, photographed a different flower of the same species,  and picking the layouts based on the person’s preference.

In 1958 nocturnal migratory species were observed to naturally turn and yearn to fly in their respective north-south directions relative to the time of year.  While in captivity, this behavior was replicated using a synthetic night sky inside a planetarium. However, when this was removed, the subjects were disoriented and lacked proper positioning. In addition, when the planetarium was reversed, the birds too reversed the direction of their desired movement. This concept was then elaborated on in 1967 by determining which starts or constellations were used by these subjects.  It was presumed that the north star, a large and fixed beacon, would be used, however it was determined that constellations near the north star, such as the big and little dipper, were used instead.  The subjects also showed flexibility and were able to utilize several constellations for travel when other were removed.

Foraminifera are ocean dwelling amoeba-like protists that build shells known as tests. The shell is referred to as a test because some of the protoplasm of the unicellular organism covers the outside of the test. Tests have chambers that are added as the cell grows. Shells or tests can be made of sand and bits of discarded shells that adhere to an exuded sticky substance, a hard keratin-like material, or calcite (calcium carbonate).  Foraminifera can be planktonic or benthic. Many tropical beaches are composed of sands made primarily from the skeletons of benthic foraminifera. Much of the ocean floor that is less than 4.000 m deep is covered by calcareous ooze composed of microfossil shells made of calcite. Foraminifera that secrete tests of calcite are not typically found below this depth because their skeletons dissolve. The calcite compensation depth (CCD) is the depth at which calcite dissolves and is typically 4,000 to 5,000 meters.  Below this depth forms that construct their tests from cemented grains of sand or other foreign particles are more common. 

NA species migrate on a north-south axis due to the fact that their wintering ranges lie south of their breeding ranges as well as the fact that the major mountain ranges in this region also follow this direction, such as the Appalachian or Rocky Mountains, preventing lateral travel. Species in EU and Asia migrate in a East to West direction due to the presence of major mountain ranges and deserts that spread on this axis such as the Alps and the Greater deserts of the middle east. These routes are sometimes fixed, ie species that have colonized a new land will occasionally return to their ancestral territory before embarking or they will eventually realign with the traditional route.  

There were some very significant differences between my figure and the figure that was replicated of mine. The first significant difference is the size of figure itself. The original figure being 2000x2000 pixel and the replicate being 300x200 pixels. In addition to the whole figure itself, each image itself in the multi-panel figure has much smaller dimensions in the replicate. Visually, size of both overall figure and individual images have a great difference. There was also much more white space between each image in the replicate than in the original figure that was used to divide each image in the figure.

Another major difference was the labeling of each image. In the replicate, there was an absence of labels in each image to distinguish them from one another. Meanwhile in the original, it contained image labeled, A, B, and C on the upper left-hand corner of each image to identify each.

A third major difference would be the difference in the images themselves. For image “A”, there was a difference in the angle or orientation at which the image was taken, both vertically and horizontally. Vertically, the replicate was taken at a much higher angle, taken at a close birds-eye-view. Horizontally, the replicate was taken in a direct line of sight as oppose to the original which was taken further left. The distance of the image taken relative to the plant was also greater in the replicate. For image “B” there were angle and distance differences as well. The vertical image angle of the replicate was directly above the flower, the original was lower in angle. The horizontal image angle is most noticeable. The replicate was taken at a horizontal 90-degree difference than the original. The distance, similar to image “A” was further in the replicate than the original.

The range map differences were quite noticeable as well, including the size, range, and color. The size of the range map in the replicate is much smaller as they included both North America and South America whole. In the original, it is focused primarily on South America where the plant range is limited to. The range of the plant on the replicate includes most of the Caribbean to include Cuba, Haiti, and the Dominican Republic. The original does not extend the range through the Caribbean. The range map itself in the replicate has a white background as oppose to the original which has the original light grey color background.

The photos is Figure 2 are larger than in Figure 1. The map in Figure 2C has more countries filled in red than in Figure 1C. In Figure 1, the labels of each photo are are located on the bottom left of Figure 1A and Figure 1B and on the top left of Figure 1C. In Figure 2, the labels are on the top left for each different photo, but the labels are significantly bigger than on Figure 1. Figure 1 also has more space between the individual photos compared to those is Figure 2.