1• Read Chapters 10 & 11 (10thedition; Ch 2 & 3 for 9thedition)• Reading & laptops for Discussion Section! (stopwatches should arrive later this week)• Independent Projects Start Brainstorming!AnnouncementsResearch Opportunity • Graduate student: Meghan Still ([email protected])• Research Lab: Dr. Mike Ryan• Project topic: Influence of social stimulation on the behavior and hormonal state of male túngara frogs. • Tasks include: Video, call, and hormone analyses• Expectations: Inquisitive, enthusiastic, and hard working student, desire to learn new computer programs and lab techniques, work a set schedule of ~10hrs/wk, able to begin ASAPCredit: A. Dunn23Outline: Weeks 2 & 3• Genetic Influences on Behavior• Environmental Influences on Behavior• Nature vs Nurture Continuum4Today’s Outline• Two Examples of independent projects• Candidate Gene Approach to BehaviorThe Influence of Thermal Detection and Physical Appearance of Prey Items on the Behavior of the Amazon Tree BoaEmily PowellJustin ChanSumit PatelSara GoyzuetaSammy Song5OutlineI. IntroductionII. Question of InterestIII. HypothesisIV. Methods and Experimental DesignV. Analysis and ResultsVI. Conclusion6Heat Sensory in Snakes-Independent evolution in Boidae and Viperidae-Two pits on Viperidae and one or two rows of pits on the lips in Boidae-used for detection of endothermic prey78Study Subject: Corallus Hortulanus Good Research Subject- Two rows of large labial pits- Remains defensive even in a captive environment- Feeds on a variety of prey items, but studies have found they prefer endothermic prey.- Native to the Amazon Rainforest in South America- Mostly arboreal hunters- Live bearing (like all boas)- Adult length of 6-7 ft9OutlineI. IntroductionII. Question of InterestIII. HypothesisIV. Methods and Experimental DesignV. Analysis and ResultsVI. Conclusion10Question of InterestI. Does Corallus hortulanus prefer to strike at prey with a higher heat index?I. Do they pinpoint the body temperatures of their preferred prey or do they prefer higher temperatures in general?II. Does the appearance of a prey item influence Corallus hortulanus to strike?11OutlineI. IntroductionII. Question of InterestIII. HypothesisIV. Methods and Experimental DesignV. Analysis and ResultsVI. Conclusion12HypothesisI. Corallus hortulanus will prefer an increase in prey temperature but will react most strongly to body temperatures of warm blooded prey.II. Corallus hortulanus will prefer prey with the appearance of a rodent or a bird.Null HypothesisI. Corallus hortulanus shows no preference for prey based upon temperature or appearance.II. Corallus hortulanus shows no preference for prey based upon temperature.III. Corallus hortulanus shows no preference for prey based upon appearance.13OutlineI. IntroductionII. Question of InterestIII. HypothesisIV. Methods and Experimental DesignV. Analysis and ResultsVI. Conclusion14Experimental Design- 6 snakes- 4 control triggers- Wooden balls- 4 different temperatures (78˚F, 100˚F, 105˚F, 120˚F)- 3 models- Bird, rodent, lizard- Each at respective body temperature15Sushi (Male)Captive RaisedDreamsicle (Female)Captive RaisedDaffodil (Female)Wild CaughtPocahontas (Female)Wild CaughtLizzy (Male)Captive RaisedTuscany (Female)Wild Caught1617http://youtu.be/I5QaCwmRQlw18OutlineI. IntroductionII. Question of InterestIII. HypothesisIV. Methods and Experimental DesignV. Analysis and ResultsVI. Conclusion192021Results- Significant difference between percentages of snakes that struck at the lizard model vs percentages for the rest of the models (P<.001)- Nonsignificant trend found via ANOVA for all controls and models (P=.088)- Significant difference via T test between Control at 100˚F and rodent model at 100˚F (P=.029)- No significant difference via T test between Control at 105˚F and bird model at 105˚F (P=.111)- *No significant difference via ANOVA between the strike times of individual snakes means no corrections needed (P=.957)22Conclusion- Snakes were reluctant to strike at the lizard model but readily struck at the control model of the same temperature. This suggests that they may have avoided the lizard because it looked reptilian in nature. Studies show that adult Corallus hortulanus do not feed readily on ectothermic prey.- Snakes preferred higher temperatures, but after 105˚ F, there was no difference between preferences. This indicates that the snakes do not pinpoint prey temperatures, but they do not show any increase in preference for temperatures beyond prey temperatures. This is probably because they do not encounter a wide range of temperatures in their environment. So anything above ambient temperature is most likely a prey item.- Snakes likely preferred rodent prey models rather than bird prey models because studies show they feed primarily upon rodents and only secondarily upon birds.23Conclusion- Our results show evidence for Corallus hortulanus as a generalist predator.- This species is adaptable to a wide range of prey given that it is warm blooded or doesn’t appear to be a reptile.- Because of the adaptability of this species, it is unlikely to be threatened so heavily by invasive species threatening its prey supply.- Future studies would increase sample size.- We would also test the models at different temperatures as well to see if there was a preference for the natural temperature of the prey.24Male Headstanding and Energetics in Male-Male Competition and Courtship in Xiphophorus nezahualcoyotlGina Calabrese, Robert Ian Etheredge, Rachael McCoy, and Kathrine Ross25Mate selection: getting his/her attention• Fin displays• Circle swims• Up & down swimming• Gliding• And….headstanding?26Headstanding• Observed in X.cortezi and X.nezahualcoyotl• Tilt head at 45º angle to substrate• M-M competition and courtship in males, (aggression & coaxing, respectively)• Courtship in females (receptivity)• Signals resource holding potential?27HeadstandsQuickTime™ and aH.264 decompressorare needed to see this picture.28Headstanding in Xiphophorus nezahualcoyotlHypothesis: Headstanding is a signal of energetic potential of males in male-male competition AND courtship• Correlation between standard body size and sword length and frequency of headstands?29METHODS30X. nezahualcoyotl• 12 males• 3 females• Fish taken from Brackenridge Field Laboratory• Males screened for headstanding behavior• 9 males exhibited headstanding behavior31Materials•