Tuesday, June 4, 2019

pillbugs and their preferred habitat conditions

pillbugs and their pickred habitat conditionsIntroductionTo sufficiently grasp and understand the experiment on animal behavior, it is crucial to be knowledgeable of the organisms being observed, as well as the sundry(a) types of animal behaviors present in nature. In this experiment the observed organism was the pillbug. Pillbugs, are excessively known as sowbugs or woodlice. They are classified as terrestrial isopods as they belong to the phylum Arthropoda, subphylum Crustacea, class Malacostraca, and order Isopoda. Morphologically they consist of three automobile trunk parts which include the head, thorax, and abdomen. They withstand cardinal prominent pair of antennae and 1 inconspicuous pair, simple eyes and seven pairs of legs. The thorax consists of seven separate segments and thither are paired appendages, called uropods, that are located at the end of the pillbugs abdomen. The color of the pillbugs can vary from bluish gray to white and they could have a standard or not have one. With female pillbugs, leaf-like growths appear on the under cheek of the bugs at the base of some of the legs. These pouches are where the developing eggs and embryos are held. On the male pillbug, the copulatory organs are the result of modification in the form of elongation of the first two appendages on the abdomen. An immature isopod will exuviate four to five times. These young isopods resemble the mature form of the isopod, with the exception of their small size in comparison to that of the adults. The juveniles molt in two stages. The tolerate half molts first and then two or three days later the front half molts. This different molting can ca intention the colouring between the two halves of the isopod to differ. Nutritionally isopods are omnivores or scavengers who feed on decaying or dead plants and animals. Because Isopods br immersehe with gills, they can only live in field of views that have high humidity, such as under rocks and logs, in leaf litter or in crevices. Some species are nocturnal. Their predators consist of both vertebrates and invertebrates. Like former(a) animals, isopods such as pillbugs exhibit their own interesting behaviors. When disturbed, some species will roll up into a ball. They walk fairly quickly, even walking everywhere one another. Environmentally, isopods have both positive and negative effects. The positive impacts of isopods include, within their immediate surroundings, a minimal amount of soil improvements. Unfortunately, large populations of these isopods can eat and damage the plants in greenhouses and southern states. Some of these fundamental interactions and descriptions of these isopods is clear from just observing them.These isopods, as well as other animals, exhibit mevery types of response to receptive input, a response that is known as behavior. The study of an animals behavior is called ethology. Two simple categories for behaviors are learned and innate (inherited). The behaviors that an animal uses to place itself in its roughly favorable surroundings are known as orientation behaviors. When the animal is stimulated by such things as light, heat, dampure, sound, or chemicals, they often exhibit taxis, with is the animals apparent motion toward or away from a stimulus. In contrast to this is kinesis, which is a random movement that does not lead to orientation with respect to a certain stimulus. another(prenominal) type of animal behavior is called unbeliever behavior. This type of behavior is exhibited when animals respond to one another with aggressive or submissive response. It is often the case that these agnostic behavioral displays are a method of asserting dominance. Animals also have specific rituals and sets of activities that are involved in finding, courting and mating with another element of its species. Such activities are known as mating behaviors. Pillbugs exhibit, even just when being observed, many of these behaviors. One, the agnostic beh aviors, involves the larger isopods appearing to fight.Soil conditions have various pHs. Some plants grow best in virulent conditions, whereas some grow best in basic conditions. Most, however, grow best in areas where the pH ranges from 6.5 to 7.2, 7 being inert. Hydrochloric acid, HCl, (0.1 M) has a pH of about 1.1 and Potassium Hydroxide, KOH, (0.1 M) has a pH of about 13.5. These two chemicals exhibit pHs at the extremes of the pH scale. Detritus, on which isopods feed, has a more(prenominal) acidic pH. When organic matter decays, H+ ions are produced, thus adding acid to the soil. The acidity limit for plants tends to be no lower than about 4.5 to 5.6 on the pH scale. The vapor pressure of a liquid refers to the concept that the process of evaporation, in a closed container, will proceed until the number of molecules returning to the liquid is suitable to the number of molecules that are escaping. When this equilibrium, the vapor is called saturated and the pressure of tha t vapor, which is normally expressed in mmHg, is referred to as the saturated vapor pressure. The vapor pressure of HCl is the about the alike(p) as water, which is approximately 20 mmHg at room temperature, 22 C. The vapor pressure of KOH is about 2 mmHg for a 45% KOH solution.5The purpose of this experiment was to use pillbugs to examine animal behaviors, such as taxis, to examine habitat elections, and crack whether these isopods prefer moist or dry habitats, dark or light habitats, and acidic or caustic environments. It is hypothesized that, habituated that pillbugs posses gills, for which moisture is needed to help function properly, the pillbugs would prefer moist over dry environments. In addition, it can be hypothesized that, given that the pillbugs live under rocks and feed on decaying organic material, which releases acid into the soil, they would prefer the dark rather than light conditions and the acidic over the caustic environment.Materials and MethodsWaterpipetFil ter Paper (2 pieces)Choice sleeping accommodationScissorsSoft Brush10 PillbugsStopwatchTo observe pill bugs and their preference for moist versus dry conditions, a choice sleeping accommodation, consisting of two petri dishes connected to one another, was obtained and lie with puree news theme publisher. Two pieces of filter paper were cut to fit the houses. One was then moistened, using a pipette, with a few drops of water. The second piece of circular filter paper was left dry. The moistened filter paper was placed at the bottom of one sleeping room, domiciliate 1, and the dry filter paper was placed at the bottom of the other, house 2. Then, using a dotty brush, ten pillbugs were obtained from the ocellus of pillbugs, and then placed into the chambers. besides using a soft brush, five pill bugs were placed in the dry chamber while the remaining five were placed in the moist chamber and the chambers were closed. This pillbug keep down for each chamber was then save for time zero legal proceeding. Using the stopwatch to track time, the count of pill bugs on each side of the choice chamber was then recorded every 30 seconds for ten minutes, and continued even when some may no overnight have been move or were all on one side. Notes were taken on the actions and interactions of the pill bugs throughout the ten minute period. Once ten minutes had elapsed, the pillbugs were returned to the stock culture.Black PaperWhite Filter PaperChoice bedchamber10 PillbugsSoft BrushScissorsStopwatchTo determine the preference of pillbugs between light and dark habitats and conditions, a choice chamber with two connecting petri dishes was line with two different types of paper. One piece of normal filter paper and one piece of black paper were both cut to fit the chambers. Next, the bottom of the inside of one dish, chamber 1, was cover with the unaltered, white filter paper and the other dish, chamber 2, was lined with the black paper. Then, using a soft brush , ten pillbugs were obtained from the pill bug stock culture, five of which were placed in the black-paper lined chamber and the remaining five were placed in the white paper lined chamber. The choice chamber was then closed. The initial pill bug count, 5 in each chamber was then recorded in the table. For a period of ten minutes, using a stopwatch to track time, the count of the pillbugs on each side of the choice chamber was recorded every thirty seconds. In addition, notes about the interactions of the pill bugs were taken throughout the ten minute period. The count continued to be taken, regardless of the lack of movement from the pillbugs or the concentration of all ten in one chamber. After the ten minutes had elapsed, the pillbugs were returned to the stock culture.White Filter Paper (2 pieces)0.1 M HCl (Hydrochloric Acid)0.1 M KOH (Potassium Hydroxide)Pipettes (1 or 2)Filter Paper (3 Pieces)3 Choice house10 PillbugsScissorsStopwatchTo determine the preference of pillbugs i n terms of basic versus acidic conditions, a 3-choice chamber was set up. Three pieces of filter paper were cut to fit the chambers. Using a pipette, about four drops of 0.1 M HCl were placed in a circular pattern about the paper. Another piece of filter paper was sprinkled with 0.1 M KOH in the same manner as was done with the hydrochloric acid. The HCl and KOH were applied to the filter paper in such a way that the paper was not drenched in the chemical. One chamber, the one connected to two other chambers was lined with an unaltered piece of filter paper. One of the two remaining chambers, chamber 1, was lined at the bottom (inside bottom) with the acidic filter paper and the remaining chamber, chamber 3, was lined at the bottom with the basic filter paper. Using a soft brush, the ten pill bugs were all removed from the stock culture and placed in chamber 2, the middle chamber consisting of the unaltered paper. The chambers were then covered and the pillbug count was recorded in the table for the initial time of 0 minutes. For the next ten minutes, the count of pillbugs in each of the three chambers was recorded every thirty minutes. The data continued to be collected even when they were no longer moving between sides or were all on one side. After the ten minutes had elapsed, the ten pillbugs were returned to the stock culture.Results skirt 1 government issue of Pillbugs in Wet vs. Dry sleeping accommodations at Various timesTime(min.) government issue in Wet put up list in Dry ChamberOther Notes055Begin moving instantly0.528Large number shifts together to one side119One more baby follows1.537 armed combat between two larger isopods255Even out again2.555Move about but come back to even one not moving364 much to wet chamber3.546Back to Dry Chamber455Crawling on underside of paper4.546Fighting to get from one side to another537Large pillbug still not moving5.564Other pillbugs begin gathering about non-moving pillbug673Pillbugs piled on top of one anothe r6.555Pillbug begins to move again746to a greater extent to Dry Chamber7.555Back at even864Continual switch from chamber to chamber8.573Begin gathering at wet chamber991More join wet chamber9.573Crowded, a few go to dry chamber1091Return to wet chamberTable 2 Number of Pillbugs in Lighter vs. Darker dismal Chambers at Various TimesTime(min.)Number in LightChamberNumber in Dark ChamberOther Notes055Begin moving instantly0.537Move to dark side128More to dark side1.528Remain, no general movement228No overall movement2.537Begin going to white side337No overall movement3.546Moving to twinkle side428Move to dark side4.555Equalize again537Fighting to get to dark side5.555Equalize again646More to Dark side6.573Piling up to get to lighter side773No overall movement7.582More in lighter side891More in lighter side8.573Move to dark side955Equalize again9.537Move to darker side1046Young follows adult to other sideTable 3 Number of Pillbugs in Neutral, Acidic and Basic Chambers at Various Time sTime(min.)Number in Neutral Chamber (Control)Number in Acidic ChamberNumber in Basic ChamberOther Notes01000Immediate endeavour0.5253Move to acidic1352Stay around outside of chamber1.5622Quickly out of acidic and into neutral area2433More to basic area2.5523Away from acidic area3235More slowly moving to basic area3.5217Movement to basic chamber4406Pillbugs all out of Acidic area4.5118Most in Basic area5145Some return to acidic chamber5.5316Slowly moving out of Acidic chamber and into neutral and basic chambers6415Out of basic and into neutral6.5316Back into basic area, around outside of filter paper7316No overall movement7.5406All gone from acidic area8307More to basic area8.5406Small shift9307Reverse of shift9.5208More to basic area more slowly than before test10109More to basic areaFigure 1 Fluctuation in Number of Pillbugs in Wet and Dry ChambersFigure 2 Fluctuation in Number of Pillbugs in Lighter and Darker Colored ChambersFigure 3 Fluctuation in Number of Pillbugs in Acidic , Neutral and Basic ChambersDiscussionTable 4 sightly Number of Pillbugs in Wet vs. in Dry ChambersTime(min.)Number in Wet ChamberNumber in Dry ChamberAverage of Pillbugs in WetAverage of Pillbugs in Dry0550.5281191.5372552.5553643.5464554.5465375.5646736.5557467.5558648.5739919.5731091 substance of Pillbugs1081025.1434.857Table 5 Average Number of Pillbugs in Lighter vs. Darker-Colored ChambersTime(min.)Number in LightChamberNumber in Dark ChamberAverage of Pillbugs in White (Light)Average of Pillbugs in Dark0550.5371281.5282282.5373373.5464284.5555375.5556466.5737737.5828918.5739559.5371046Total of Pillbugs931174.4295.571Table 6 Average Number of Pillbugs in Neutral, Acidic and Basic ChambersTime(min.)Number in NeutralChamberNumber in Acidic ChamberNumber in Basic ChamberAverage of Pillbugs in Neutral ChamberAverage of Pillbugs in Acidic ChamberAverage of Pillbugs in Basic Chamber010000.525313521.562224332.552332353.521744064.511851455.531664156.531673167.540683078.54069 3079.520810109Total of Pillbugs70301103.331.4295.238Figure 4 Comparison of Average Number of Pillbugs in Wet Chamber vs. in Dry ChamberFigure 5 Comparison of Average Number of Pillbugs in Lighter-colored and Dark-colored PaperFigure 6 Comparison of Average Number of Pillbugs in Acidic, Neutral and Basic ChambersIt was hypothesized that the isopods (pillbugs), given their possession of gills for respiration and that they live underneath rocks and logs, places where light is not in abundance, would prefer the wet chamber over the dry chamber and the dark chamber over the light chamber. It was also hypothesized that, considering that the pillbugs feed off of decaying organic material, which in the process of decaying increases the acidity of the soil, these isopods would prefer the acidic chamber (the one with HCl), over the caustic (with KOH) and neutral chambers. The data collected from preforming the experiment partially supports the hypothesis. The average number of pill bugs in e ach chamber, was calculated by summing the pillbug count for all twenty-one times in one chamber and then doing so for the next and then dividing these fares by the total number of pillbugs counted. In each case this number was 210. The results show, as seen in Table 4 and Figure 4, that the average number of pillbugs in the moist chamber over ten minutes was about 5.143 while the average number in the dry chamber was about 4.857. This higher average for the moist chamber illustrates taxis with a movement toward the stimulus of moisture. The second portion of the hypothesis was also supported by the data collected. Table 5 and Figure 5 both show that the average number of pillbugs in the chamber with white filter paper was about 4.429, in comparison to the average number in the chamber with dark paper, which was about 5.571. These results are consistent with the known habitat of isopods such as pillbugs. The hypothesis for third portion the experiment, however, was not supported by the data collected. Table 6 and Figure 6 both show that the pillbugs actually prefer a basic environment, one with drops of KOH, over an environment with no chemical additives and the environment with the addition of drops of the strong acid HCl. The average for the number of pillbugs in the neutral environment was about 3.33, for the acidic environment the average was 1.429 and for the caustic environment the average was about 5.238. These results could possibly be explained by the higher vapor pressure of HCl in comparison to that of the KOH. With a higher vapor pressure, the HCl would have gasified more easily and quickly, thus getting into the gills of the pillbugs and causing them irritation. This irritation would explain their clear lack of fondness for the HCl permeated filter paper. The lack of pillbugs accumulating on the plain filter paper can possibly be explained by its complete lack of moisture, and that the antennae on the pillbugs would not sense any chemical or som ething of that nature, that would attract the pillbugs to that chamber. The interaction of the pillbugs inside the choice chambers is indicative of agnostic behavior, as seen in the fighting of the pillbugs. Human error, such as counting, would not play any, or any significant role, in the results of the experiment.This experiment and the results obtained from it support most of the hypothesis, but conflict with and not support another portion. The results support the preference that pillbugs have for moist and dark environments, but suggests that pillbugs prefer more caustic environments to neutral and acidic environments.Citations

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