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We conclude that the varied levels of noise pollution observed at the feeders under study resulted in notable differences in response to mobbing calls. Local individuals at the quiet feeder readily responded to all mobbing calls as well as a number of additional individuals that were not present prior to the experimental mobbing calls. Furthermore, mobbing calls played by the noisy feeder with louder background noise elicited a fractional response with only a small portion of the local fauna responding to the call. This difference suggests that black-capped chickadees (BCCH) in close proximity of the quiet feeder as well as individuals outside visible range were able to hear and appropriately respond to the mobbing calls being played while those within close proximity the loud feeder were unable to appropriately respond. It is less likely that individuals outside of our visual perimeter were able to hear and respond to the mobbing calls in the high decibel area due to the elevated levels of background noise. Of note, another variable that could have been controlled was the specific mobbing call used. BCCH are able to determine perceived threat and relay this information via adjusting the syllable composition and rate of their mobbing call (Baker et al., 2002). By using a mobbing call that typically warrants a vigorous response we would expect to observe a larger experimental response, potentially in higher decibel areas.

I have concluded that this creature is a mammal given that when examining the born of their young ones they looked altricial with their mother providing lactation for the altricial newborns. When the young were born they were hopeless and depended on their mother for guidance and nutrient’s. They would suck milk from one of the mothers 6 mamae and remain in their mother’s pouch until they were ready to look for food on their own with the guidance of their mother and father. This took about 6-8 months until the young were a bit stronger and could leave but still had their mother’s guidance. Throughout this time the male father would help the mother and grab food for her and the young ones as she stood behind to protect them from their predators since development of their spikes didn’t start until they were about one year old. 

Their forelimbs are a bit bigger than their hind limbs. There spikes are located posteriorly ranging from sizes of about 8-12 inches long. Their spikes are used as an extra defense mechanism from their predators like eagles, vultures, or hawks. I’ve tried to stay as far away from them as possible but still at an observable distance from them. Since at times if they felt my presence was too close their spikes will erect, and it showed that they were able to defend themselves easily. They have heterodont teeth and in particular bunodont molars that help them eat insects and plant species like leaves from the shrub trees. Their digestive tract is similar to that of an insectivore species in which they have no cecum and a short intestine. Their favorite plant species is the monkey brush vines also known as Combretum rotundifolium, which are due to its vibrant colors.

Black-capped chickadees are year-round residents of Massachusetts that display complex behavioral and social systems in order to maximize their chances of survival through the harsh winter months. To do this they are able to differentiate between a wide range of vocalizations with a wide range of syllables (Grava et al., 2011). Since they do not seek refuge from the weather by migrating like many other Massachusetts residents, they must compensate with other behavioral mechanisms and join multi-species flocks. One such behavior that constantly grabs the interest of researchers is mobbing. Chickadees, among other birds, will group together in an attempt to ward off predators by repeatedly attacking and chasing off the threat. Communication is an essential part of this display, as chickadees must be highly responsive to the call and close enough to hear the call from others.

Introduction

    Human development, globalized transportation and the industrialization of resource harvesting all produce large amounts of anthropogenic sounds that are suspected to have negative effects on local fauna. This effect, coined noise pollution, has been a subject of increasing levels of study as several animal behaviors in both terrestrial and marine systems are thought to have been affected (Francis et al., 2009). These results suggest that increased levels of noise pollution exert pressure on vulnerable species, particularly those that heavily rely on vocal communication.  Evidence shows a correlation between elevated levels of background noise and decreased species density and reproductive success, indicating that areas of high noise likely have some detrimental effect on the local fauna (McKenna et al., 2015).  Anthropogenic noise sources, such as heavy construction or large congregations of humans, are commonplace at Umass Amherst and these factors have likely begun exerting pressure on local fauna, including the black capped chickadee.  

Tetrahymena cells are unicellular predatory ciliates that produce both sexually and asexually. To begin the experiment we made a master tube of 5ml of Tetrahymena and 5ml of India ink. Immediately after and then every ten minutes for forty minutes a random sample of 100ul of Tetrahymena cells were taken and added to 50ul of glutaraldehyde, killing the cells without damaging the tissues. Once mixed, 35ul of the dead Tetrahymena were put under a microscope and then ten randomly chosen cells were observed at 10X and had their black food vacuoles counted. The counts were averaged and the standard deviation calculated. Tetrahymena not randomly chosen were excluded from the experiment. This experiment showed a tendency of the Tetrahymena cells to increase their consumption rate over time, as seen by the upward slope of the graph.

However, the roots that penetrated in the light grew at a 45° angle, while the roots that penetrated in the dark grew at a 119°. This difference exhibited the fact that light is the major contributor of which direction the adventitious roots will grow. The plants that were not submerged underwater in this experiment did not grow any adventitious roots. This can be attributed to the the ethylene levels not being able to reach a high enough level in the three days the experiment was conducted, while the ethylene could get trapped and reach a high enough level in the submerged plants. An important note to make is that the adventitious roots grow in the same patterns in different media: water, soil, and styrofoam beads. This is indicative that the growth patterns are independent of the medium.  

Initially, they studied the rice plants root growth in response to white light and total darkness. Over five days, one batch of excised rice stems was grown in a light environment and another was grown in a dark environment. At the end of the growth period, the stems that had grown in the dark had sprouted roots, while the stems grown in the light did not. The root angle of the dark grown stems stayed consistent throughout the time period at an average of 119°, and the roots grew at a consistent rate. This experiment showed that darkness is a stimulus for the plant to increase root penetration in order to find more nutrients, which is how the plants know when to grow adventitious roots underwater.  When full plants were grown in light and dark while submerged, the plants grown in the light grew adventitious roots.

This experiment was done over a long period of time. The patient had to get multiple surgeries for the implantation of the electrodes and needed a relatively long recovery time in between surgeries. A time line of the procedures done are shown in fig. 2A. Time was also taken to work on strengthening the muscles used; there was a long period after the injury, before the experiment, when the muscles were not used at all. Before trying to move his actual arm, the patient worked on visualizing the movement, then worked on moving a virtual reality arm. Fig. 2B shows the virtual reality arm and the movement he was trying to achieve. Fig 2C shows the different stages of visualizing the movements, then using the virtual arm to see the movements and the actual movement of the arm. And fig. 2D shows the brain activity correlated with the different movements for the virtual reality and real arm.

Haploids HB1, HA1, and HA2 could not grow on their own as they could not synthesize their own adenine. This makes sense because they all had an ade mutation that makes them mutant deficient for adenine biosynthesis. Haploid HA0 could grow on its own, meaning that it can synthesize its own adenine. Again, this makes sense because this haploid strain had no mutations in any of its ade genes. The cross between HB1xHA1 did not proliferate. Because the cross contained one MATa and one MATα, sexual reproduction is possible. However, because it did not proliferate, it means that their alleles are not complementary. Next, the cross of HA1xHA2 did not proliferate. In this cross, both the haploids were MATa, therefore sexual reproduction is not possible and no proliferation is expected. The cross HB1xHA2 did proliferate. Both of these haploids could not grow on their own, however, when they were crossed they were able to proliferate. This cross contains one MATα and one MATa, thus the proliferation is caused by the complementation of their alleles. Finally, the cross of HB1xHA0 was able to proliferate. This cross needs to be furthered examined because although HB1 is MATα and HA0 is MATa, one cannot assume they sexually reproduced. As we know, HA0 is able to proliferate on its own, so either their alleles are complementary and it proliferated or it’s just HA0 proliferating and HB1 dying off.