mqpham's blog

In the laboratory environment, the two species Lemna minor and Salvina molesta were brought together to show how reliance on the same resources will result in elimination of one of the species. This is an increasing problem in natural ecosystems throughout the globe. As invasive species are brought to new environments, they devastate the local ecosystem and displace the native species. This experiment revealed the potential threats of careless introduction of foreign species to different environments where they pose a threat to species that already occupy the same niche. Although cohibitation is a possibility, it is not typically the case when there is a reliance of the same limited resources.

Not all of the food consumed by humans today were made accessable to all until after the Columbian Exchange. Besides the new people and new land, there were new foods that Europeans have never seen. Some of these crops included corn, tomato, potatos, chili, and chocolate. Corn originated from central and north america. Potatos were originally found in moutainous regions of south america. Tomatos came from Mexico and were orignally thought to be poisonous because of its bright red color. Chocolate also came from central america. Although the initial meeting of the new and old world populations brought about diseases that dimished the population of the new world, overall, the exchange of new crops and livestock greater increased the world human population due to a greater diversity in diet and available staples.

The definition of competitve species is a species whos phenotypes causes a fitness decrease in a competitor species. In bacteria, this is observed in phenotypes such as secretion of digestive enymes and production of antibiotics as a result of biotic competition with other bacteria, as opposed to environmental pressures. Competitor species must also overlap a single resrouce. When this occurs, there are two types of competition, passive and active. In passive competition, one organism outcompetes the other by using the same resource more efficiently. In active competition, the organism may directly harm the other. In the case of bacteria, this may be done by producing chemicals that harm other bacteria of the same niche. Thee possible results of such competition include having one species dominating the other, coexistence over time due to divergence of resource use, or territorial niches are developed. The later is observed in microbial colonies that when initially mixed, separate into patches on the surface of agar. The result of competition is typically a decrease in diversity but increase in ecological stability. The long-term effect depends on selection pressures of the environment.

In the past, ecologists thought there was a negative correlation between species abundance and niche width of a species. However, current ecologists agree that there is a positive correlation between the abundance and niche width of a species due to the increase in a diversity of resrouces consumed, thus an increase in tolerance of various environmental conditions. However, invasive species are therefore successful when they have a wider niche than that of native species, therefore, doing better with competition. A superior competitor can use the same resources of a native species and cause competitive exclusion of the native species. Co-existance of species that rely on the same resources is explained by the abundance of resources for both species and resource partitioning.

Brine shrimp, or Artemia, are crustaceans that inhabit inland salt water lakes. They are known for their ability to adapt in fluctuating levels of salinity. They are slightly over 1cm in length, and although small, are of great importance to the ecosystem. They are a source of protein for not only for fish, but often nesting birds as well as migrating birds. In the Great Salt Lake, brine shrimp are important to the local economy as they are often sold as food for fish as well as shellfish raised for food for humans. Their life cycle consists of dormant cyst (eggs), that hatch and develop into Naupliar stages. Eventually, they develop into juveniles that become adults. Femals will hold the eggs.

Overall differences in the panels of the figures were first noted. This included the shade of color used in each square of the panels in the two figures. In the original, the green is lighter in panel A. In figure 1, panel B, the color used was rose, but the replication, a color closer to maroon is used. The shade of purple used is lighter in panel C of the original, but the blue is a lighter shade in the replication in panel D of figure 2. The labeling of the figures are different as well. In the original multi-panel figure, the labels are placed in the furthest corner of the panels, but in the replication, the labels are placed in the corner of the images themselves. Furthermore, no captions that detail the species and their interactions are provided in the replication. Lastly, the quality of the images were immediately noticed as well, with the clearer images being in the original multi-panel figure.

Three main factors that could have accounted for the differences between the overall figures as well as the images of the panels were identified. Some could have resulted from the conditions in which the photos were taken. Other possible causes for differences could stem from an interpretation of the methods description, and the methods itself, as in the description that was provided or variables that were not controlled.

Parts to control were the timing of the experiment and weather to make sure the waterfowl were present. Aspects of the condition of the environment were also controlled to minimize differences. The device on which the photos were taken was also controlled to ensure similar quality of images. The position of the waterfowl in relation to the camera and to each other were also controlled. This included the distance from the camera and from the other waterfowl in the image.  The food which they were given was controlled to ensure they would have the same response to the food they were given (this was cheerios). The amount and interval of time in which food was also controlled to make sure there was enough food to take the necessary photos. I noted how the waterfowl were lured together to take the photos to ensure the opportunity to take the photos were the same, considering the waterfowl are mobile. The method in which specific interactions such as when the geese bit one another was noted to ensure a similar image since such interactions were brief. This was done with the screenshot function of the iPhone after a video was taken. Construction of the panel itself was controlled with regard to color of the background for the photos to ensure similar results in the replication. It was noted that green was put to figure A, rose to figure B, purple to figure C, and turquoise to figure D. The labeling was also controlled, the location of the box (size 70x70 pix), as well as the font (Calibri size 20) were controlled too. 

The number of genes in organisms do not reveal complexity. Rice as it turns out, has more genes than humans do. Genome is a collection of genes. Humans have roughly 20,000 genes in the genome, half of which is shared with zebra fish. The similarity is even greater between chimpanzees and humans. Approximately 95% of our genes are identical with the primate, this includes insertions and deletions. The difference comes from how much of the genes are turned on and when they are turned on. Segmentation is the process by which organisms express these genes in a particular order and forms the phenotypic expression of the body parts. The way the genes are activated will play a role in the outcome of development. The differences in humans and chimpanzees partly come from the different segmentation, expression of genes when they are turned on at different times.

Distillation is the process by which two liquids are separated and purified. The process requires a mechanism that will turn the liquid into the vapor phase and convert it back to the liquid phase. Since different liquids have different boiling points, the identities of the unknown liquids in a mixture may also be identified. Once the boiling point of a liquid is achieved, a plateau is reached in which the liquid phase becomes converted to the vapor phase. This property is used to distinguish the two liquids. In a distillation, the first lower-boiling point liquid is first collected when the mixture is heated because it will evaporate first. Once a plateau of the first liquid is reached, the temperature will rise sharply afterward. This is signaling that the next boiling point is about to be reached. To purify the liquids, a separate collection vial is used until the next plateau is reached. When the next plateau is reached, the vial is switched again, which will contain the second pure liquid.