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Overview Draft

Submitted by jmalloldiaz on Thu, 11/01/2018 - 15:33

Animal locomotion requires mechanical power exerted by the muscles, and chemical energy in the form of ATP. In the case of a flying bird, wing shape and flight style can influence its power curve, which represents the relation between mechanical power and forward velocity. The aspect ratio of a wing is determined by its width and length. Short and broad wings such as those of a magpie, provide great maneuverability for navigating in dense environments like a forest. Meanwhile, long and narrow wings have a higher aspect ratio and are useful for speed and soaring like the wings of albatrosses, which spend most of the time soaring over the ocean in search of fish.

 

Impact Draft

Submitted by jmalloldiaz on Thu, 11/01/2018 - 14:03

Studying the behavior of Misumena vatia when offered the choice between different backgrounds will broaden our knowledge and understanding of some aspects of the life history of a key player in the ecology of New England fields. Due to its relative abundance and easy rearing in a lab setting, Misumena vatia is an optimal subject for investigating the mechanisms of crypsis and color change in spiders. This set of experiments is directed towards the spider's ability of distinguishing different colors and responding to them in order to blend in with the environment. It is important to approach the behavioral choices of this spider towards different backgrounds based on variations of the three primary colors, because we need to establish a set of parameters of color recognition before introducing new variables. Once the experiments are concluded, we will investigate if such behavioral responses have a broader implication by being correlated to flowers that its prey visits with more frequence.

Specific Aims and Background Draft 2

Submitted by jmalloldiaz on Thu, 11/01/2018 - 09:46

The aim of this study is to determine if crab spiders show any preference towards backgrounds of different colors. Due to its ambush hunting strategy and ability to change color, we hypothesize that when given the choice between two options, Misumena vatia will choose the most optimal background in regards to its actual body coloration.

In Test 1 we will study spider preference between yellow and white backgrounds.

In Test 2 we will study spider preference between dark gray and light gray backgrounds.

In Test 3 we will study spider preference between white and gray backgrounds.

In Test 4 we will study spider preference between cyan and green backgrounds.

In Test 5 we will study spider preference between magenta and red backgrounds.

In Test 6 we will study spider preference between abstract and a simple backgrounds.

Color Change

Submitted by jmalloldiaz on Thu, 11/01/2018 - 09:29

Animals have evolved multiple strategies for blending in with their environments, from the iconic color-changing common chameleon (Chamaeleo chamaeleon), to resembling a bundle of floating seaweed like the leafy seadragon (Phycodurus eques). These strategies are englobed in a broader term known as crypsis, and play an important role in predator-prey interactions for both hiding and hunting. One example of crypsis as a predation strategy is the case of the flower crab spider Misumena vatia. This species is capable of hunting relatively large prey such as bees, with the help of its ability to change color between yellow and white.

Specific Aims and Background Draft

Submitted by jmalloldiaz on Thu, 11/01/2018 - 09:27

Animals have evolved multiple strategies for blending in with their environments, from the iconic color-changing common chameleon (Chamaeleo chamaeleon), to resembling a bundle of floating seaweed like the leafy seadragon (Phycodurus eques). These strategies are englobed in a broader term known as crypsis, and play an important role in predator-prey interactions for both hiding and hunting. One example of crypsis as a predation strategy is the case of the flower crab spider Misumena vatia. This species is capable of hunting relatively large prey such as bees, with the help of its ability to change color between yellow and white.

Such colors are produced by ommochrome pigments, which are mostly found in the eyes of arthropods, but are also present as granules in the bodies of spiders. The white coloration in these crab spiders is the result of overlapping gunanine and uric acid, which generates type I granules. Meanwhile, the yellow color is produced by type III granules, which combine the reflectance from the white color with other merged granules. A crab spider undergoing color change has a combination of type III and type II granules, which are a transient stage between the yellow and white pigments.

http://jeb.biologists.org/content/211/5/780 - color change mechanism

Writing for Persuasion - Draft

Submitted by jmalloldiaz on Fri, 10/26/2018 - 09:51

The future of domestic dogs is at serious risk due to an extremely aggressive new retrovirus. Despite scientists having found a vaccine that can cure the disease, it seems that there is only enough to cure one pregnant mother and her puppies. This poses an important ethical dilemma, since researchers are convinced that they must choose a breed of dog to be saved. Considering this from the Occidental point of view, dogs are our equals and our ethics tells us that the right thing to do would be saving all dogs regardless of their origin. Thus, making any decision that favors one specific dog would be unjust towards the rest.

We would need more information about the retroviral vaccine and pregnancy stage of the mother, but it seems that only her and her pups will survive and they will be the original ancestors of all future dogs to come. Considering this situation, the mother and her pups face a grim future, since the next reasonable step would be to exploit them by keeping them constantly pregnant via artificial insemination in order to increase the gene pool and avoid a genetic bottleneck that would only postpone the extinction of dogs for a few more generations. Thus, trying to save a specific dog breed would not be a good solution, since we would need as much genetic diversity as possible.

Another fact that we should take into consideration is that viruses evolve as well. Viruses are interested in their own survival, and must keep a balance between mortality and efficiency to infect other organisms. If a virus kills its host too soon, it will have less chances of coming into contact with other potential hosts to infect them and ensure its survival. That is the reason why it is possible that dogs and viruses may reach a balance between them and both will survive without human interference, the virus by becoming less virulent, and the dogs maybe by arising mutations that confer them more resistance. 

Still, if the virus maintains its virulence and dogs are doomed to go extinct unless a vaccinated pregnant dog saves them, I would choose a stray dog to be that savior. Stray dogs often have no definite breed, which would be important for avoiding genetic bottleneck. As well, stray dogs are often forgotten by society because people tend to prefer pure breeds.

By choosing a stray dog, the new generations of dogs would be composed of completely different and unique individuals. Humanity would amend all the damage it has caused on dog breeds via artificial selection, such as the respiratory distress that current pugs suffer on a daily basis. And hopefully people would no longer discriminate dogs by their appearance, and these kind animals would finally be treated as the companions that humans started domesticating thousands of years ago, instead of being used as symbols of status by some people.

Logos Draft

Submitted by jmalloldiaz on Fri, 10/26/2018 - 09:51

We would need more information about the retroviral vaccine and pregnancy stage of the mother, but it seems that only her and her pups will survive and they will be the original ancestors of all future dogs to come. Considering this situation, the mother and her pups face a grim future, since the next reasonable step would be to exploit them by keeping them constantly pregnant via artificial insemination in order to increase the gene pool and avoid a genetic bottleneck that would only postpone the extinction of dogs for a few more generations. Thus, trying to save a specific dog breed would not be a good solution, since we would need as much genetic diversity as possible.

Parasites and Monarch Butterfly Migration - Conclusion

Submitted by jmalloldiaz on Mon, 10/22/2018 - 09:59

I chose this paper because I am interested in evolution and long-distance migratory species like monarch butterflies are an interesting subject of study for their host-pathogen interactions. The selective pressure that the parasite imposes over the butterflies is added to the physiological cost of migration, thus setting the scenario for adaptations to overcome or tolerate the infection in order to successfully reach their wintering grounds. Although this paper focused mostly on the actual capacity of different monarch populations to reach their wintering grounds during fall migration, it did not investigate the evolutionary aspect of this phenomenon. A follow-up study could look at the genomes of populations in northern and southern latitudes, in order to see if there are genetic differences involved with overcoming the cost of parasite infection. This research could be useful for the conservation of monarch butterflies, which have been consistently declining over the past 20 years, in order to plan the introduction of resistant monarchs in declining populations.

Summary Discussion Draft

Submitted by jmalloldiaz on Mon, 10/22/2018 - 09:11

The results support the hypothesis that infected monarchs would travel shorter distances, and that among infected individuals shorter distances are correlated with higher parasite loads. The researchers suggest that infected butterflies from more northern locations were not able to reach their wintering grounds in Mexico, thus backing the "migratory culling" idea of reducing parasites among a population by removing infected individuals. Since there was no significant effect of latitude on the odds of infection, the researchers propose that the flight performance of monarch butteflies has a greater effect on the chances of reaching their wintering grounds than the incidence of parasite transmission among populations.

Summary Results Draft

Submitted by jmalloldiaz on Sun, 10/21/2018 - 19:24

In order to ascertain the origin of the monarchs, hydrogen isotope (δ2H ) data was collected, knowing that it decreases northwards. Infected monarchs had higher average δ2H values, showing that such individuals originated in southern latitudes, while those born further north had lower δ2H values. As well, monarchs originated from northern areas had larger forewings, but the correlation between δ2H values and wing area was not significant in infected individuals. Regarding parasite loads, butterflies from southern populations closer to their wintering grounds were more heavily infected. Finally, citizen science data indicates that there is no significant effect of latitude on the odds of infection.

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