TY - JOUR
T1 - A micro-geography of fear
T2 - Learning to eavesdrop on alarm calls of neighbouring heterospecifics
AU - Magrath, Robert D.
AU - Bennett, Thomas H.
PY - 2012
Y1 - 2012
N2 - Many vertebrates eavesdrop on alarmcalls of other species, which is a remarkable ability, given geographical variation in community composition and call diversity within and among species.We used micro-geographical variation in community composition to test whether individuals recognize heterospecific alarm calls by: (i) responding to acoustic features shared among alarm calls; (ii) having innate responses to particular heterospecific calls; or (iii) learning specific alarmcalls.We found that superb fairy-wrens (Malurus cyaneus) fled to cover to playback of noisy miner (Manorina melanocephala) aerial predator alarmcalls only in locations where miners were present, suggesting that learning rather than acoustic structure determines response. Sites with and without miners were well within the dispersal distance of fairy-wrens, and philopatric males and dispersing females showed the same pattern, so that local genetic adaptation is extremely unlikely. Furthermore, where miners were present, fairy-wrens responded appropriately to different miner calls, implying eavesdropping on their signalling system rather than fleeing from miners themselves. Learned eavesdropping on alarm calls enables individuals to harvest ecologically relevant information from heterospecifics on an astonishingly fine spatial scale. Such phenotypic plasticity is valuable in a changing world, where individuals can be exposed to new species.
AB - Many vertebrates eavesdrop on alarmcalls of other species, which is a remarkable ability, given geographical variation in community composition and call diversity within and among species.We used micro-geographical variation in community composition to test whether individuals recognize heterospecific alarm calls by: (i) responding to acoustic features shared among alarm calls; (ii) having innate responses to particular heterospecific calls; or (iii) learning specific alarmcalls.We found that superb fairy-wrens (Malurus cyaneus) fled to cover to playback of noisy miner (Manorina melanocephala) aerial predator alarmcalls only in locations where miners were present, suggesting that learning rather than acoustic structure determines response. Sites with and without miners were well within the dispersal distance of fairy-wrens, and philopatric males and dispersing females showed the same pattern, so that local genetic adaptation is extremely unlikely. Furthermore, where miners were present, fairy-wrens responded appropriately to different miner calls, implying eavesdropping on their signalling system rather than fleeing from miners themselves. Learned eavesdropping on alarm calls enables individuals to harvest ecologically relevant information from heterospecifics on an astonishingly fine spatial scale. Such phenotypic plasticity is valuable in a changing world, where individuals can be exposed to new species.
KW - Acoustic communication
KW - Alarm calls
KW - Eavesdropping
KW - Interspecific communication
KW - Learning
UR - http://www.scopus.com/inward/record.url?scp=84856253294&partnerID=8YFLogxK
U2 - 10.1098/rspb.2011.1362
DO - 10.1098/rspb.2011.1362
M3 - Article
SN - 0962-8452
VL - 279
SP - 902
EP - 909
JO - Proceedings of the Royal Society B: Biological Sciences
JF - Proceedings of the Royal Society B: Biological Sciences
IS - 1730
ER -