Instars: A Journal of Undergraduate Research (Texas Digital Library - TDL E-Journals)
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A Survey of Mosquitos in the College Station Area
No full textMosquitoes pose not only an annoyance and nuisance to humans, but also a danger to health. West Nile Virus, Malaria, and Dengue fever are just a few of the diseases vectored by mosquitoes. Entomologists keep track of species of mosquitoes and their ranges through surveys. A collection survey of the College Station metropolitan area was conducted to assess the species currently present. It was hypothesized that Culex quinquiefasciatus would be the most prevalent species in the area; however, no specimens were collected during this survey. Further surveys are required to determine the most prevalent species of mosquitoes in the College Station area
Comparative Adult Longevity of Chrysomya rufifacies (Diptera: Calliphoridae) (Macquart) and Cochliomyia macellaria (Diptera: Calliphoridae) (Fabricius)
No full textMany forensically important Calliphorids reap their importance from use of their relatively known development time. Both Chrysomya rufifacies and Cochliomyia macellaria are in the family Calliphoridae, and have been found to invade human corpses. This allows a postmortem interval (PMI) to be established, and this levies them forensic significance. If more points of comparison pertaining to elements of development or time lived of Ch. rufifacies and C. macellaria could be correctly utilized, then a more accurate PMI could be produced. In this study C. macellaria and Ch. rufifacies adults (F1) were reared from maggots obtained on a highway (P1) in order to record the length of time each individual F1 adult lived. The mean longevity of C. macellaria was found to be about 4 days longer than the longevity of Ch. rufifacies and showed no apparent positive correlation between observed general body size and the length of time an adult live
Effects of Question Wording on Eyewitness Testimony
No full textThis study examined the effect of the wording of interview questions on eyewitness testimony. Participants were male and female college students (Mean age = 19.1). Participants were presented with a short video of a vehicle accident. They were then given a questionnaire consisting of six items. To study the impact of question wording on testimony, the wording of one of the items was changed between two conditions. This item asked either how fast the vehicles were traveling when they “contacted” each other, or how fast the vehicles were traveling when they “smashed into” each other. On average, participants in the “smashed into” condition reported slightly higher speed estimations than participants in the “contacted” condition. However, the difference between the two groups was not large enough to be statistically significant
Effect of Black Pepper on Killing Ants
No full textThis study was performed to determine if black pepper could effectively kill ants (Hymenoptera:Formicidae). Ants were collected from 3519 Treeline Dr. at the Reserve at College Station apartments. The ants were taken from the same colony and placed in two bowls. One was sprayed with a mixture of black pepper and water and the other was not. After an hour, the sprayed bowl had a number of dead ants. This experiment concluded that this treatment is effective in killing ants
Adult Longevity in Females and Males in Chrysomya rufifacies (Macquart)(Diptera: Calliphoridae)
No full textThe longevity of Chrysomya rufifacies (Diptera: Calliphoridae) was observed from adulthood until death to determine whether females or males lived longer. Several Ch. rufifacies maggots were collected and fed cow liver for development. Once these maggots emerged, these now adult flies were fed sugar and water. When they reached full adulthood, additional liver was given to them, which served as a protein meal and, also, as a place to oviposit. These maggots were reared in a laboratory setting until they pupated. Approximately, 90 of a combination of males and females were gathered. These were counted to see how many females (43) and males (47) were present. Additional sugar and water was fed to them daily until they all died. The data gathered were analyzed by using a T-test in SPSS by having P>0.05 as significant where males lived longer than females, and P<0.05 as insignificant where females lived longer than males. The results showed that the P value came to be 1.619834569, which showed a great significance value. This demonstrated that sometimes females died sooner than males. The figures below demonstrate the comparisons with both sexes and the longevity of each.
Orthopteran populations at Lick Creek Park in College Station, Texas
No full textMany orthopteran species are pest that cause considerable crop damage, so a generalized survey of this insect order is beneficial for agricultural businesses. Orthopterans were collected at Lick Creek Park in College Station, Texas because this area is adjacent to farmland. The collected orthoptha were separated and categorized into suborders, families, and subfamilies by using the books as a key. They were also separated into matures and nymphs and by sex. Most of the Orthopterans collected were from the subfamily Melanoplinae. Surveillance of the Orthopteran population during the harvest season in agriculturally active area is imperative because Melanoplinae is one of the largest subfamilies and contains several of the worst orthopteroid crop and grassland pests
Forensic Entomology and the Effect of Ortho Pesticide on Decomposition in Sunny Conditions
No full text A study of the effects of the use and type of insecticide on decomposition was conducted at the Rangeland Science Park in College Station, TX. A treated and a control chicken cadaver were laid out in the field in sunny conditions to observe decomposition and insect-cadaver interactions. We hypothesized that the use of insecticide would decrease the rate of decomposition compared to non-treated organisms and, specifically, that organisms treated with Ortho brand insecticide would have less insect activity than those treated with Spectracide. Results showed that the control cadaver was heavily decomposed while the treated cadaver was still in the early stages of decomposition. Both cadavers had insect activity, but fly larvae were more active on the control while adult flies were more active on the treated cadaver. Knowledge of factors that can affect decomposition is important because it can, consequently, affect post mortem interval estimates
Survey of Pests and Beneficial Insects in Conventional and Transgenic Cotton
No full textA cotton patch that was divided into two sections, one being conventional cotton and the other being transgenic cotton was surveyed for insects. The cotton was transgenic for Bacillus thuringiensis (Bt), a naturally occurring bacterium in the soil that is toxic to Lepidoptera larvae, which is one of the most common pests in cotton crops. The arthropods that were collected were separated into two categories, one being whether the arthropod was a pest to the crop and the other being if it was beneficial to the crop. There were more pests on the transgenic cotton than on the conventional cotton but there were also more beneficial insects in the transgenic cotton than in the conventional cotton. In none of our samples was Lepidoptera larvae encountered. If Bt cotton has the most promising effect on reducing pests, then there would be fewer pests on the transgenic cotton than on the conventional cotton. Our results, showed that there were more pests on conventional cotton than in Bt cotton. This information is important for the implementation of integrated pest management strategies. The use of Bt transgenic cotton may not be the best method to manage pests.
Sexual Dimorphism of Pupal size in Calliphorid Carrion Feeders (Diptera:Calliphoridae)
No full textChrysomyia rufifacies (Macquart) (Diptera:Calliphoridae) and Cochliomyia macellaria (Fabricius) (Diptera:Calliphoridae) are two Calliphorid carrion feeding species of significant importance in forensic investigations. Pupal weight was predicted to be an effective indicator of sex and species identification between the two related species when reared in a laboratory. In order to test the effectiveness, wild maggots of both species were reared and the pupae of their offspring were weighed and sexed. There was no significant weight difference found between male and female pupae of both species. However when each species was compared to the other, it was observed that male and female pupae of Ch. rufaficies weighed significantly more than their C. macellaria counterparts. These results could simplify the identification of species at the pupal stage, thereby expediting research involving the two species
Survey of Larvae and Adult Mosquitoes of Medical Importance in Bryan/College Station, Texas (Diptera: Culicidae)
No full textMosquitoes are potentially one of the most deadly animals in the world. They are known to vector diseases such as Yellow fever and West Nile virus. Surveying urban areas is important fo ridentifying what species of mosquitoes are present in order to dtermine what potential diseases are present in the eniornment. The focus of this experiment was to identify what species were present in the Bryan/College Station, TX area. Mosquito larvae were captured by allowing the females ot oviposit in previously placed containers and were monitored over the course of two months. By properly identifying the species of local mosquitoes, prevention methods can be taken into account in order to lower mosquito prevalence and ultimately lowering the chances of mosquito-borne diseases