The Influence of Number of Larval Mass on the Change in Temperature - Lab Report Example

Practical 2: Forensic Entomology Name: Course: Lecturer: Institution: City & State: Date: Practical 2 to Investigate the Influence of Number of Larval Mass on the Change in Temperature: Forensic Entomology Abstract Forensic entomology uses insects and other relatives to help in legal investigations. Basically, forensic entomology focuses mostly on insects, and this greatly helps scientists in this field to help in carrying out of legal investigations. This scientific advancement has facilitated legal inquiries or investigations in the modern world. Considering the fact that insect species differ from place to place, the instar larvae has consistency and a remarkable succession in the world. For entomologist to estimate the PMI using the larvae and also to determine the time a given corpse has been lying in a given area, they use of the larvae from the insects and through this, they are able to effectively estimate the PMI. In this case, then the insects are used as the nature’s intelligence, since they always have their first show on the corpse. The life cycle of an insect feeds on cadaver, which is potential reservoir of flesh that is not digested. In some circumstances, corpse can hold variety of drugs, which the victims might have consumed before meeting their death. This may be a source of the root cause of the death to the victim (Smith 1986). Therefore, analyzing the insects’ larva, these drugs may be recoverable and may involve opiates, benzodiazepines and their metabolites, and barbiturate Phenobarbital. Although it is necessary to analyze the larvae, to date, there is no any big deal pertaining to the available information, which indicates the purpose of the drugs in any decomposing body containing larvae. In this practical, I have examined the larvae to determine the effects of temperature in relation the number larvae present. Temperature is usually said to affect the number of larvae during growth and development of insects. Scientists concerned in the study of insects consider temperature as a very critical factor in the development of larvae and so, they put great emphasis on temperature as a factor (Goff 2000). Introduction Thigmotaxis is a certain feature that the larvae relies on to experience the larval masses in relation to their cause in increase in temperature. In many occasions, if the maggot larvae mass is high, then the temperature can raise up to 20. Forensic entomology uses the study of insects and other arthropods to assist in legal investigation issues. It has three general classifications, stored-products, medicolegical, and urban. This paper uses medicolegal to analyze the results obtained using number of larvae at different temperatures. Arthropods make the life cycle for other living organisms that exist on earth bearing in mind that they eat all the dead living things thus completing the cycle (Compobasso, Di Villa and Introma 2001). Blowflies are the first insect to land on the dead bodies where they undergo metamorphosis to form the instar larvae, which in this case is the test sample for the analysis. This experiment uses the instar larvae as the test sample for analysis. This is basically because blowflies are usually the first insects to arrive on dead bodies. After they arrive, they then undergo a complete metamorphosis and this is how they form the instar larvae. Using the larvae and the eggs lay on a corpse during investigation, different stadiums in determining the life cycle of the insect are used to have proper speculation regarding the death period. It is necessary whenever one is handling this fluon, to be careful, since, as a safety measure, it is important to know that Fluon can cause irritation when in contact to the skin or eyes. Therefore, it is important to have gloves to wear to protect the hand from the corrosive nature of the Fluon and observe the laboratory mannerism. Aims of the experiment Most of the investigations have in many cases been the major cause for research therefore; there is a need to have these tests relating to the use of larvae tests. In essence, the cases involving epistemology need to have more considerations to have all the weight on the need to develop the right means to achieve the problems met in the research (Catts and Goff 1992). Methodology In this experiment, it involves the use of five beakers in a layer of diluted fluon around the top of each. This is to prevent the larvae from escaping. Before the whole practical commences, the following are the necessary materials for the project: 5  ml beakers Dish that can fit 5 beakers Perlite for insulation of beakers in dish Thermometer Indeliber marker for marking the sample larvae 1800 late second instar larvae Labels Fluon, 50:50 with distilled water Protective gloves Forceps Cling film The larvae are placed in beakers in the following order: In the first beaker, 40 larvae are placed, in the second beaker it has 80 larvae, the third beaker it has 160 larvae, and the fourth beaker it has 320 larvae. All the beakers are placed in the dish and each beaker is surrounded by the solution of diluted fluon. The following procedure should be followed when doing the practical: Step 1: ensure that the dish is away from direct sunlight Step 2: Make a record of the temperatures of each mass of maggots by the use of a thermometer in the mass after every 30 minutes of the equilibrium. Step3: Record the ambient air temperature by taking the temperature of the fifth beaker at the same time as you sample the larval temperatures. Step 4: Repeat this temperature assessment after a period of 30 minutes Step 5: calculation for the mean and the Standard deviation of the temperatures for the populations of maggots using the last sets of data from the whole class Step 6: plot a graph of the results, that is, temperature against the larval numbers. The results obtained are as shown in the table below. Temperature Larval mass 16.7 0 17.2 40 17.5 80 18.1 160 18.6 320 Results The increase in temperature is directly proportional to the increase in larval members. This increase is shown in the graph below: A Graph Of Temperature Against The Number Of Larvae Discussion The number of larvae is directly proportional to the rate of temperature change. Therefore, an increase in the number of larvae causes a direct increase in the temperature for the test sample in a given beaker. Using the data obtained for the experiment, the total mean and standard deviation may be obtained using the following equations. Using the number of larvae in specific beakers: At 0 mean temperature = 199.9/ 13 = 16.7 At 40 mean temperature = 205.9/13=17.2 At 80 mean temperature= 210.4/13 = 17.5 At 160 mean temperature = 217.3/13 = 18.1 At 320 mean temperature =222.7/13=18.6 For standard deviation, the following equation may be applicable to find the standard deviation for different larval mass temperatures for all last sets of data give the standard deviation of 0.98082 From the table, it is clear that the temperature increase was as the number of larvae increased. Therefore, it is clear that as the number of larvae increased in one place they produced more heat thus causing an increase in temperature. This is a clear indication that the number of larvae in a colony is directly proportional to the rate of temperature increase (Benecke 2001). The relation between the number of larvae and the temperature is indicated in the graph above. Conclusion From the experiment, it was found that there was a relationship between the larval mass and the temperature. The trend established was that with high number of larval mass, there was a high level of associated temperature. This relationship was found to be strong as the regression curve had a R2 = 0.906. In essence, the number of larval mass can in great chances control the increase in temperature for the whole set up. The overall temperature for tall the beakers tend to increase with the number of larval mass increase. References Benecke, M 2001, ‘A brief history of forensic entomology,’Forensic Science International, 120, pp. 2-14. Compobasso, C P, Di Villa, G and Introma, F 2001, ‘Factors affecting decomposition and dipteran colonization.’Forensic Science International, 120 (2), pp. 18-27. Catts, E P and Goff, M L 1992, ‘Forensic entomology in criminal investigations,’Annual Review of Entomology, 37, pp. 253-272. Goff, M L 2000, A fly for the prosecution, Harvard University, Harvard. USBN0-674-002200-2 Smith, KGV 1986, A manual of forensic entomology, British museum, London. Read More