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Killer Whale Calf Vocalization Development: Understanding Cultural Transmission Through Acoustics. By: Courtney Kneipp BeamReach Marine Science and Sustainability School Fall 2005 Hendrix College 06 Conway, AR. Introduction. Killer whale : endangered species
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Killer Whale Calf Vocalization Development: Understanding Cultural Transmission Through Acoustics By: Courtney Kneipp BeamReach Marine Science and Sustainability School Fall 2005 Hendrix College 06 Conway, AR
Introduction • Killer whale : endangered species • distinct cultural archetypes are both irreplaceable • Motivation for Investigation: • each pod has a unique acoustic culture • may offer insight into the development of their vocal repertoire and acoustic cultural transmission process. • Cultural Debate • Boweles et al. (1988), calf develops repertoire until puberty • Deecke’s(1999) “gene-culture coevolution”
Vocalization Development Studies • Luna – supports Deecke’s “gene-culture coevolution” theory • Enggist-Dueblin and Pfister(2001), cultural transmission in ravens • Subsong, plastic song, crystallized song • Fripp et al(2004), dolphins ability to learn signature whistles of pod through members whom they associate rarely. • Hubbs-Sea World Research Institute • calf can vocalize within days of birth, but sound production is shaped with age • first vocalizations loud, high pitched calls that bear no resemblance to adult-type calls • Boweles(1988) • vocalization may begin with shorter pulsed calls occurring at a higher frequency.
Materials for Acoustic Observation: - “Ears” -“Elephant Ears” - High impedance amplifier - Marantz PMD660 recorder, used to record sound files * digitizing rate of 44100 -Range * 90- 150 dB Materials for Visual Observation: - Data Sheet - Spotter with camera * special thanks to my fellow crew mates! - Video Methods *The Ishmael Journey: a series of unfortunate events
Data Analysis Procedure Sonogram of an S19 call, depicting where I measured the fundamental frequency of the tone. .
S1 Call Sonogram of an S1 call, depicting how I measured the call duration. Black lines indicate start and end points of my measurement.
Results My S19 fundamental frequencies shown varying around Ford’s(1990) S19 average fundamental frequency for the beginning of the tone. Yellow line depicts my S19’s average in comparison to Ford’s average, in red.
S1 Fundamental Frequency My measured S1 fundamental frequencies compared to Ford’s average fundamental frequency for an adult S1 call.
S1 Call Duration Call duration of my S1’s compared to average call duration of Ford’s S1’s.
Good news for Ishmael! Ishmael located call at 173 and 187 degrees.
Results Revisited • Overall, my S19 and S1 fundamental frequencies were higher than Ford(1990)’s fundamental frequencies average for those calls. • My S1s’ durations were not significantly longer than Ford(1990)’s S1’s duration for adult calls. • Ishmael can localize underwater sound sources…future study!
Discussion • Higher S1 and S19 fundamental frequencies could indicate that a calf was present • Higher fundamental frequencies could also mean change in adult call frequency over the past 20 years. • Further studying vocal development to better understand the acoustic cultural transmission process. * interesting: L-pod calve making a J/K-pod call?
I dedicate this experience to CoachEd, my grandfather, who lived a life of Patience, Endurance, And Compassion Every day Of His Life. I Will Miss You.