![]() (Kirschel et al.: Evolution 2011) Ecology versus Isolation: : Science 1997) Despite gene flow, there is divergence in morphology and song Minimum freq Maximum freq Delivery rate Herz Herz #/sec *** *** *** N = 72 57 N = 72 57 N = 72 57 Song (Slabbekoorn & Smith: Evolution 2002) Body weight Wing length Bill depth grams mm mm *** *** * N = 45 60 N = 45 61 N = 44 61 Morphologyįrequency (kHz) Time (sec) 8 6 4 2 8 6 4 2 Habitat-dependent differences in the maximum frequency of song type III II I III I II III 0 2.0 4.0 6.0 Acoustic divergence may be driven by habitat-dependent masking NOISEĮcology versus Isolation: do glacial rainforest refugia play a role in divergence and speciation? *** p < 0.001 * p < 0.05 Rainforest Ecotone (Smith et al. (Slabbekoorn & Smith: Evolution 2002) Case 1: little greenbuls of Africa ( Andropadus virens ) Reverberations Sound transmission Frequency Amplitude Timeįrequency (kHz) Time (sec) 0 2.0 4.0 6.0 8 6 4 2 8 6 4 2 8 6 4 2 A B C Sonograms of ‘closed’ habitat bird species (Slabbekoorn Nature’s Music 2004)įrequency (kHz) 0 2.0 4.0 6.0 8 6 4 2 8 6 4 2 8 6 4 2 A B C Sonograms of ‘open’ habitat bird species Time (sec) (Slabbekoorn Nature’s Music 2004)Īlso within species: Habitat-dependent divergence in trill rate in the rufous-collared sparrow Time (seconds) Frequency (kHz) (Handford 2004) Songs vary between populations of the same species and between species Can song variation between populations play a role in speciation? Geographic separation needed? Or by ecological divergence?Įcological speciation in birds Morphological Divergence Song Divergence Reproductive Isolation Divergent Selection (Slabbekoorn & Smith:. ![]() 1986) Flycatcher song Without soundīirdsong plays a role in Territorial defense and Mate attraction Mate attraction: experiment with pied flycatcher (Eriksson & Wallin: Behav.Ecol.&Sociobiol. Territorial defense: experiment with great tits Birdsong Other sound (Krebs, Ashcroft & Webber: Nature 1978) Most birds have elaborate ways to communicate acoustically! The acoustic equivalent of the rainforest is found in the underwater soundscape of coral reefsĪnd we have the urban jungle… What are the consequences? Stress, disturbance, deterrence Masking of relevant sounds Sonogram: graphic representation of the sound energy distribution (Slabbekoorn JASA 2004) … or complex with many species more or less overlapping in time, frequency, and space … and biotic sound sources depending on the local animal communityĪ soundscape can be simple with one or few species acoustically active at the same time… The soundscape is build up by abiotic sound sources… Soundscapes of the forest Implications for evolution Applications for conservation Soundscapes Function of bird song Environmental selection Habitat degradation Urbanisation Song and speciationĪll habitats have their own specific soundscape ![]() Hans Slabbekoorn Institute of Biology, Leiden University The Netherlands Soundscapes of the forest Implications for evolution and applications for conservation Dr. Sounds melt and juxtapose each other producing a dynamic which allows us to recreate the unique and personal experience of the different landscapes, even though they are all different -water, whether as a swell, running water, or only as a rumour, shows up constantly as the perfect metaphor of the cyclical nature of the world and of the passing of time.Paisajes sonoros del bosque: Implicaciones para la evolución y aplicaciones para la conservación - Hans Slabbekoorn This happens at the end of One-year Cycle #3 or One-day Cycle #2.Įach of the pieces are built over a succession of several sound strokes (birds chorus, insects crowds, deer bellows, cowbells, etc.) which are coated by the acoustics of these spaces through which we can listen to either the scale or the distance and we can even imagine the location of the one who is recording. The aim is to catch their own geo and biophonic features, which are briefly invaded by the human presence, as if it was a line or a boundary. Manuel Calurano has depicted this recurring nature of time, in which he takes two different scales as a reference -the annual and the daily cycle- and both are transformed by a compression of time.Ĭiclos Sonoros is the result of intensive field recording sessions made in five different locations of the Iberian Peninsula. It is by means of the clock hand movement, or by the division of time in days, weeks, months, years, and so on, that we can create an almost unalterable plot which prevents us from our own subjectivity. It also helps us to understand time itself, in the sense that it may be altered by different kind of stimuli. Listening is one of the best experiences which make us aware of the complex nature of time and of our relationship with it.
0 Comments
Leave a Reply. |
Details
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |