asalamon's blog

Among different species, there is some varioation in chromomsome numbers that are tolerated by the species.  For example, plants are quiet tolerant and can survive with varying chromosome number.  In nature, three mechanisms which chromosome numbers can chamge is through meiotic nondisjunciton, mitotic abnormalities, and interspecies crossing.  Meoitic nondisjuction is when the chromosomes do not seperate properly during gamete production.  This can happen in both meiosis 1 and meiosis 2.  In meosis 1, gametes are monosomic and trisomic.  In meosis 2, half the gametes formed will be normal while the other half are abnormal.  In a very rare case, there is complete nondisjuction when all the chromosomes go to a single cell.  For example, a dipoloid species would form a tetraploid species.  The condition is called autopolyploidy.  In interspecies crosses, the recult is allopoidy.  The first generation with the cross will likely survive but when the chromosomes line up  in meosis there might be some issues.  It is possible but not likely.  

There are key behavioral traits that humans had in their environment of evolutionary adaptiveness that creates the eating patterns we experience now.  One key difference is the risk and energy early humans put into getting the food.   With the advent of cars and grocery stores, humans expend less energy to get more food than would be available in their environment of evolutionary adaptiveness.  As a result, the calorie intake exponentially exceeds the calorie expenditure used to get food.  The human body also evolved to hold large energy reserves for times when food is scarce.  In our novel environment, this means our body is designed to hold onto the food we eat.  If we exceed the amount of food we should intake, we are designed to retain the energy as fat which increases our vulnerability to obesity.  In our environment of evolutionary adaptiveness, our central nervous system has evolved to crave “palatable, energy-dense food”.  Because our novel environment put these types of food in easy access, there is nothing stopping us from over-indulging.  All these eating patterns humans evolved to have were designed to capitalize on high energy food and maximization of energy storage.  With the availability of food in the novel environment, it is important to recognize these behavioral patterns and make choices to fight these behaviors.

    Throughout the evolution of humans, we have consistently changed to a novel environment which no longer matches our environment of evolutionary adaptiveness.  As a result, humans have become vulnerable to different conditions we were not vulnerable to before.  For humans, a majority of physiological changes including increased brain size occurred during the Paleolithic Era which lasted for 2 million years (Easton 67).  Because a majority of the evolutionary traits which defines us as a species occurred during this time, our diet played a key role in giving us the energy and nutrients that enabled these changes.  The human diet is something that has changed considerably from the environment of evolutionary adaptiveness and we are now facing a slew of health consequences as a result.  One of major heath consequences is obesity, which often leads to the other conditions are at risk of developing.  There are two aspects of the the human diet which varies from the environment of evolutionary adaptiveness: the eating patterns of humans and the composition of the diet.  With both these factors different in the novel environment of humans, humans are now vulnerable to a variety of detrimental health conditions.

For species who do not reproduce asexually, mechanimss of sex determination are essential to the survival of species.  In humans, the sex of an individual is determined by the presence of a Y chromosome.  It is important to note that sex and gender are two different concepts.  Sex is determined by biology while gender is a social construct.  In other species, sex is determined through other mechanisms.  The sex of fruit flies is determined by the ratio of sex chromosomes and autosomal chromosomes.  Some species have their sex determined through temporal influences.  

One factor considered in the methods was the time of day the image was taken.  In the creation of Figure 1, the image was taken around 4p.m. on a Friday and there were not many people around while the photos were being taken.  In Figure 2, the outside of Harvest in panel B had a lot more people inside and outside the store. If the image had been taken closer to lunch time on a weekday, this could explain the differences between the number of people in and around Harvest.  In panel C of Figure 2, there was less salad stocked on the salad bar. More customers in Harvest could have removed the salad so the salad bar does not look as stocked as it did in Figure 1. The number of people could have been constantly moving the tongs explaining the different orientations of the tongs in Figure 2.  Since Figure 2’s photos were taken when there were more customers, they could have forced the different camera locations as they were in the way of the photos being taken from the point of view described in the methods. Time was a factor controlled in the methods that may not have been followed in the recreation of Figure 1.

As humans, one characterisitc that defines us as a species is obligate miwifery.  Although there is not guarentee and neonate would surive with a midwife or not survive without one, the changes of survival by the neonate greatly increased if a midwife is present.  There are several factors which lead to a more complicated birth which resulted in the need for a midwife.  First, obligate bipedalism resulted in changes to the pelvis which narrowed the birth canal of the pelvis as well as lead to protrusion into the birth canal by the pelvic bones to form muscle attachments.  At the same time, the brain size of humans were getting larger.  The evolution of human was pushed by both these factors at the same time.  During birth, the neonate twists in the birth canal and exits so the it faces away from the mother, therefore the mother cannot pull the neonate out like in other primate species.  

The final panel C inluded the salad bar inside of harvest.  Figure 2 had less salad in the left salad container. In Figure 2, pea snacks on display on top of the salad bar. Between each panel, the orientation of the tongs are different.  Figure 1 has apples while Figure 2 has some fruit that is orange. On the white counter of Figure 1, there is a glare of light as well as a similar glare of light on the sneeze guard of the salad bar.  In Figure 2, the black base of the salad bar below the salad bar’s counter is larger. Figure 2 has a blue arrow pointing to the left container of lettuce. The “C” letter label in Figure 1 is narrower than the “C” label of Figure 2.  A black line extending the length of the right side of the panel in Figure 2.

At Harvest, a food market on the campus of UMass, Amherst, evidence of phytophagy, the salad bar, was photographed and put into a multipanel figure including a map.  The methods and materials of creating the original multipanel figure was given to another student to replicate. The differences between the original and replicated included the perspective of the photo in each panel, the quality of the images, and the design of the multipanel figure.  During analysis, the differences were attributed to a variety of factors including time of day, stocking of Harvest, and the camera used to take the image

In Figure 2 panel B, there are more people in Harvest as well as outside the store.  A “Contemporary Indian Cuisine” sign was on display in Figure 1. In Figure 2, more walls visible on the sides of the panel as well as more ceiling of the Campus Center visible with a ceiling light included in the upper right portion of the panel.  The lights of Harvest have a glow to them in Figure 1 while Figure 2 does not have the blurred lines of the lights. Figure 1 contains a narrow blue arrow while Figure 2 contains a wide white arrow.  

In panel C of Figure 2, has less salad in the left salad container.  Pea snacks on display on top of the salad bar in Figure 2. The fruit to the left of the salad bar is not the same between figures.  The orientation of the tongs are different between each panel. Figure 1 has apples while Figure 2 has some fruit that is orange. There is a glare of light on the white counter of Figure 1 as well as a similar glare of light on the sneeze guard of the salad bar.  In Figure 2, the base of the salad bar is larger. Figure 2 panel C has a blue arrow pointing to the left container of lettuce. The C label in Figure 1 is narrow compared to the C of Figure 2. A black line extending the length of the right side of the panel in Figure 2. 

During fractional distillation, a steady, slow rate of one drop every twenty to thirty seconds is necessary for the proper separation and purification of the compounds.  The thermometer of the apparatus will keep track of the temperature of the vapors as they reach the top and condense into the vial at this consistent drop rate.  While the drops are being collected, there will be one plateau of drops at one consistent temperature.  Then, a slight dip in temperature will be observed.  During this part of the distillation, the first component of the mixture has been used up and the higher boiling point substance is being vaporized.  Because of the higher boiling point, more energy is needed to achieve this explaining the dip in temperature.  This was seen in both the known mixture and the unknown mixture.  In the transition phase between the first plateau and the second plateau, the drops, if any are produced, are not pure and should be separated from the first plateau's drops and the second plateau drops to ensure two pure compounds are formed.  To continue distillation, additional heat needed to be added to both distillations.