Lecture 6: Behavioral Ecology Part 1

Introduction

• Focus: Behavioral Ecology
  • Diverging from the textbook for today's lecture.
  • Discussion on behavioral ecology with a focus on vocal learning in wild birds.
• Logistics:
  • Lab 3 is posted online (Word and PDF).
  • Independent project details now available (20% of the final grade).
  • Lab Assignment 2 due this week by email.
  • Lab 3: Two assignments (Assignment 3 due October 1, Assignment 4 after reading week).
  • Midterm preparation slides will be shared in upcoming lectures.

Overview of Ecology Course

• Definition of Ecology: Study of organisms and their environment.
• Topics covered so far:
  • Symbiotic relationships and ecosystems.
  • Biotic and abiotic environmental influences.
  • Ecological energetics and trophic pyramids.
  • Nutrient cycling.
  • Population ecology.
• Upcoming Topics:
  • Behavioral ecology (this week).
  • Physiological ecology (next week).

Behavioral Ecology

• Definition: Study of behavior with a focus on adaptive significance.
• Key Questions:
  • Why do organisms exhibit certain behaviors?
  • Examples: Antler utility in ungulates, mate attraction, resource defense, and social structures like flocking.

Research in Behavioral Ecology

• Professor's Research Focus:
  • Vocal learning in wild birds.
  • Animal communication, conservation.
  • Understanding behaviors’ adaptive significance.
• Research Methodologies:
  • Field studies, sound recording, sound playback, radio telemetry.

Vocal Learning in Wild Birds

• Unique Behavior: Seen in songbirds, hummingbirds, parrots, cetaceans, bats, humans.
• Vocal Learning Model:
  • Sensitive phase: Critical window for sound exposure.
  • Silent period: Especially in birds.
  • Sensory motor phase: Babbling, practice phase.
  • Crystallization: Fixation of sounds in neural activity.
• Experimental Approach:
  • Use of loudspeakers on Kent Island to simulate vocal tutors.
  • Study site: Kent Island, New Brunswick.
  • High natal philopatry in sparrows allows study of vocal learning.
• Research Findings:
  • Birds learn songs from sounds heard early in life.
  • Experimentally manipulated sounds were learned by sparrows.
  • No disadvantage found for birds learning experimental songs.

Hypotheses Tested

• Re-exposure Hypothesis:
  • Animals prefer songs heard both in natal summer and post-migration.
  • Supported by experimental evidence.
• Selective Attrition Hypothesis:
  • Overproduction of songs followed by selection of neighbor-matching song.
  • Results show fewer aggressive encounters with neighbor-matching songs.

Research Implications

• Adaptive Significance:
  • Matching neighbor songs reduces aggression, conserving energy.
  • Behavior influences population-level dialects.
• Paper Reference: "Wild Birds Learn Songs from Experimental Vocal Tutors" published in Current Biology.

Conclusion

• Research Impact:
  • Validates models of vocal learning outside the lab.
  • Offers insights into animal behavior and ecology.
• Acknowledgments:
  • Funded by NSERC.
  • Collaboration with universities and students.
  • Encouragement to work with partners in independent projects.