May 03, 2013
Emily Neset ‘ 13Hamline UniversityBiology Senior Seminar Abstract:
The Affect of Temperature on House Cricket (Acheta domestica) Song Preference
In this study, we tested the effect of two treatments, hot (28°) and cold (22°C), on sexual selection preference in female house crickets. There were two sections to my testing: recording males singing at the two temperatures and then testing to see if females had a preference between these recordings. Each female was given recordings of the same individual male at both temperatures simultaneously, and seconds spent near each recording was documented to evaluate preference. No two females experienced the same male’s recordings. The results were inconclusive, as females did not spend a significantly different amount of time near either recording. This could indicate male compensation for temperature, thus maintaining a truthful signal, or female disinterest in this particular study, due to female age and prior mating experience. To conclude, house cricket females did not select between males singing at hot and cold temperatures.
Sandy Kayachith ‘ 13Hamline UniversityBiology Senior Seminar Abstract:
Male Mate Choice Copying in Guppies (Peocilia reticulata)
Sexual selection has been intensely studied in animal behavior. Intersexual selection (mate choice) is a form of sexual selection. Females of most species tend to be the chooser sex. Most studies focus on a female’s independent choice of a mate. Female’s choosiness of a mate has led to studies on mate choice copying, which has been seen in female guppies, Poecilia latipinna. In this research we examined Peocilia reticulata, on whether male guppies would participate in mate choice copying or avoid mate choice copying. Male guppies were observed on his choice between two female guppies, which were later labeled as the Chosen or Rejected Female after phase one. During phase one another male guppy was observing (Observer Male) the interaction. Female were considered “chosen” if the male guppy spent more time in their preference zone. Upon decision the male guppy were removed and for phase two of trial the Observer Male were allowed to choose from the same two female guppies. Males who chose the Rejected Female avoid mate choice copying, which suggests avoidance of sperm competition. Males who chose the Chosen Female exhibited mate choice copying, which suggests reducing the costs of finding a mate. Males who had no preference imply that they are not choosy. Male guppies did not avoid or exhibit mate choice copying.
Erik Koeppen ‘ 13Hamline UniversityBiology Senior Seminar Abstract:
The Role of the Brain in Handwriting and the Development of Individual Characteristics A common rule in handwriting analysis is that no two people share the same handwriting characteristics. However, the individuality of writing has not been well established with scientific research and studies. The brain participates in many of the on goings during handwriting and this will lead into my study. This study is ongoing but will gather the amount of handwriting needed and has gathered enough to present on. It measured the individual characteristics (departed from copybook) in the samples and statistically analyzed the data collected by CEDAR-FOX software. Eventually a database will be created allowing a time model analysis which can be quantified. The results are statistics that indicate how unique that persons handwriting is. Overall, this study would lead to a clearer scientific basis for forensic handwriting examination and provide statistical data supporting conclusions from examinations.