Page # Animal Behavior. This just in: Male lobsters may urinate in the face of other males. Write down a question about this behavior

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1 Animal Behavior This just in: Male lobsters may urinate in the face of other males Write down a question about this Today - Approaches to the study of animal 1. The description of the the the in the acquisition of a in the species and its 5. The adaptive significance of the I. The five approaches to What happens? 1. The description of the I. The five approaches to communication? What machinery is involved? the I. The five approaches to communication? What machinery is involved? the the

2 I. The five approaches to How does the of urinating on other males develop? in the acquisition of a I. The five approaches to Why has this species of lobster developed this? in the species and its I. The five approaches to And the one you ve all been waiting for. Why do male lobsters urinate on other males? 5. The adaptive significance of the Questions about can be categorized into what and how questions (proximate) and why (ultimate) questions Proximate cause - an immediate underlying cause, the mechanism Ultimate cause - the evolutionary reason for why something is the way it is. Can have adaptive and historical components. What happens?

3 communication? What machinery is involved? communication? What machinery is involved? PROXIMATE communication? What machinery is involved? PROXIMATE How does the of urinating on other males develop? communication? What machinery is involved? PROXIMATE How does the of urinating on other males develop? PROXIMATE communication? What machinery is involved? PROXIMATE How does the of urinating on other males develop? PROXIMATE Why has this species of lobster developed this? communication? What machinery is involved? PROXIMATE How does the of urinating on other males develop? PROXIMATE Why has this species of lobster developed this? ULTIMATE Why do male lobsters urinate on other males?

4 Today - examples of studies using the different approaches 1. The description of the - N o example the the in the acquisition of a in the species and its 5. The adaptive significance of the - All of next lecture communication? What machinery is involved? PROXIMATE How does the of urinating on other males d e v e l o p? PROXIMATE Why has this species of lobster developed this? ULTIMATE W h y do male lobsters urinate on other males? ULTIMATE Estradiol in amniotic fluid Aggression in mice: effects of female hormones in the uterine environment Female hormones in the uterine environment of mouse embryos Observation: Males developing between Female two females (OM) males were exposed to more female hormone, estradiol and less male hormone, testosterone than males surrounded 2M OM by two males (2M) Female hormones in the Female hormones in the uterine environment of mouse embryos uterine environment of mouse embryos Does the exposure of embryos to different concentrations of sex hormones in the uterus determine aspects of adult? 0M male Higher estradiol, lower testosterone Higher testosterone, lower estradiol 2M male

5 Hormones in the uterine environment of mouse embryos Experimental design: Mice delivered by cesarean section so position noted Hormones in the uterine environment of mouse embryos Experimental design Mice delivered by cesarean section so position noted Males castrated and given testosterone implants - why? Hormones in the uterine environment of mouse embryos Experimental design Mice delivered by cesarean section so position noted Males castrated and given testosterone implants - why? Experimenters measured aggressiveness towards strangers Hormones in the uterine environment of mouse embryos Results: Percentage attacking stranger 2M OM Interpretation? Moths evading bats Observation: When bats approached, moths were seen to change direction or engage in erratic flight. Could moths hear the bats approach?

6 Found an ear on each side of moth thorax - a tympanic membrane with 2 receptor neurons, A1 and A2 Ears Moths evading bats Question: What information do these two neurons receive and how do they direct escape of the moth? Tympanic membrane A1 & A2 receptor cells Moths evading bats Experimental design: Tethered live moths in a chamber Moths evading bats Experimental design: Tethered live moths in a chamber Put electrodes in one of the receptors Experimental design: Tethered live moths in a chamber Put electrodes in one of the receptors Exposed moths to bat-like sounds of different (loudness), frequency (pitch) and duration Moths evading bats Experimental design: Tethered live moths in a chamber Put electrodes in one of the receptors Exposed moths to sounds of different (loudness), frequency (pitch) and duration Recorded the response of the receptor

7 A1 receptor: Low Moderate High A1 receptor A1 receptor: Graded response to pulses of sound depending on (loudness) A1 receptor Low Moderate High A1 receptor: Experimenters suggested that differences in firing of the L and R A1 neuron would tell moth where the sound is coming from, allow it to move in opposite direction A1 receptor: Bat to one side Bat directly behind A2 receptor: Low A2 receptor A2 receptor: Only responded to high (loud) bursts of sound A2 receptor Low Moderate Moderate High High

8 A2 receptor: Only responded to high (loud) bursts of sound Experimenters suggested that firing of this neuron may cause shut down of central flight steering mechanisms in brain, result in the erratic flight that moths exhibit when bats are very close Moths evade bats by a very elegant and simple neurological mechanism 2 independent neurons One for when the bat is far enough away that a simple change of direction will work The other for situations where immediate evasive action is necessary - when flight path is not predictable, bats have difficulty tracking moth flight in the acquisition of a in the acquisition of a Beewolf natural history in the acquisition of a Beewolf natural history in the acquisition of a Hypothesis: When they leave the nest, they memorize local landmarks so they learn to recognize the spot How do they find their nest again?

9 in the acquisition of a Experiment 1: Experimenter mixed up the local landmarks (stones, vegetation, etc.). in the acquisition of a Experiment 1: Experimenter mixed up the local landmarks (stones, vegetation, etc.). Results: Wasps took longer to find nest entrance in the acquisition of a Another experiment? in the acquisition of a Experiment 2: Experimenter carefully moved all the local landmarks to surround a spot a meter or so away in the acquisition of a Experiment 2: Experimenter carefully moved all the local landmarks to surround a spot a meter or so away What result would you expect if the hypothesis was true? in the species and its courtship in What are the functions of courtship?

10 in the species and its courtship in Observation: male pelagic shags (a type of cormorant) perform this courtship : rapid-flutter wing waving, while head is back, pointing straight up in the species and its courtship in Hypothesis: Courtship in pelagic shag evolved from less complex courtship displays, and originated in flight intention movements in the species and its courtship in Experiment? in the species and its courtship in Experiment: Documented courtship in related species in the species and its courtship in Experiment: Documented courtship in related species Constructed cladogram based on courtship alone in the species and its courtship in Experiment: Documented courtship in related species Constructed cladogram based on courtship alone Compared cladogram based on with cladogram constructed from other evidence (here gene sequences)

11 in the species and its courtship in Experiment: Documented courtship in related species Constructed cladogram based on courtship alone Compared cladogram based on with cladogram constructed from other evidence (here gene sequences) What did they predict? in the species and its courtship in Results Wing wave Pre-takeoff Rapid Both wings in the species and its courtship in Results Good fit between the al and DNA sequence cladogram Wing wave Pre-takeoff Rapid Both wings Summary - the five approaches 1. The description of the the the in the acquisition of a in the species and its 5. The adaptive significance of the - BEHAVIORAL ECOLOGYnext time!