Woodlice Lab Report Example | Topics and Well Written Essays - 750 words

Woodlice - Lab Report Example They have a shell like exoskeleton which progressively shed as they grow. The shedding occurs in two stages were the back half sheds first followed by the front part later usually after two to three days later as opposed to the way moulting process occurs to other antropoda where the cuticle are shed in a single process. Metabolic rate is temperature dependent in woodlice which is in contrast to mammals and bird where their rate of respiration depends directly to the external environmental temperatures (Jordan 100). Woodlice are claimed to have unpleasant taste like that of a urine despite been a crustacean which is different from the taste of other crustacean like lobsters or crabs. Woodlice breathe through their plepodal lungs and live in terrestrial environment usually damp or dark places to reduce the rapid rate at which they lose water through their cuticle and excretion (Sutton, Stephen, Paul, and David 67). Although woodlice are preyed by a wide range of insectivores itâ€℠¢s the spiders that prey on them exclusively. This experiment was conducted to determine the relationship between the variation of traits and the natural selection and the hypothesis of this experiment was that the predator preying on the woodlice determine the speed of woodlice to be found in an environment (Smith, SiaÌ‚n 98). The length and dorsal plate in all woodlice was measured using a microscope and recorded. The speed of three woodlice was obtained by taking two rulers to measure the distance and then assorted utensils for simulating predation and to mimic a predator was simulated and the timer was set from the time all the three woodlice started moving until they all reach the end of the two rulers and then recorded in seconds. Woodlice where placed in large specimen dishes and the predator for this experiment which was a spider was simulated RESULTS The woodlice traits were varying as like were the highest standard deviation error was obtained from the speed and the lowest standard deviation error was obtained from the length while the standard deviation error was zero as illustrated in table(1) below Trait Dorsal plate number Speed (seconds/10 cm) Length (cm) Color (values using soil color chart) Mean 7 21.20833333 0.991666667 5.083333333 Standard Deviation 0 +10.29131828 +0.21450989 +1.248187091 Standard Deviation Error 0 +2.100706547 +0.043786648 +0.254785123 Table (1) showing traits, mean, standard deviation and standard deviation error of woodlice In the frequency distribution below blue represents the total number of woodlice while the red represent the number of woodlice that survived after the predator was unleashed. From the graph the number of survived population is higher than the total populati on between the speeds of 1-20 and the same is exhibited between the speeds of 21-40 and between the speeds of 61-80 but between the speeds of 41-60 no woodlice survived. Frequency distribution of woodlice characterized by speed DISCUSSION From the table and the frequency distribution above it is clearly that there is a relationship between the population of woodlice that survived the experiment and their speed. Woodlice that were much fast and those that are somehow slower survived more compared to those that were of average speed as none of them survived and also the predator