Transcript Inkaba Template

10th Inkaba yeAfrica/!Khure Africa (AEON)
Conference/Workshop
Lord Milner Hotel, Matjiesfontein - Karoo
29 September – 3 October 2014
Loud calls as species markers in
fork-marked dwarf lemurs
(Phaner)
D. Forbanka1, J. Masters 1
1. Department of Zoology & Entomology,
University of Fort Hare.
logo here…
Introduction
Introduction
 These lemurs are nocturnal and according to Recognition Concept
of Species, mate recognition cannot be by visual characteristics
alone.
 Recognition Concept of Species is means by which organisms
attract and recognize each other (SMRS).
 One SMRS widely followed and proven fruitful in nocturnal
primates is vocalization.
 Each species has particular loud call common to both sexes and
used to advertise their presence to companions/rivals.
 Loud calls are species specific, constant across geographic ranges provide a diagnostic tool for the identification of new species.
 However, loud call species-specificity has never been tested in forkmarked dwarf lemurs
Aim
Investigate species specificity in loud calls of
fork-marked dwarf lemurs.
Methods
Study sites
Data were collected by
following animals at
night with the aid of a
head lamp along
existing trails.
o Calls were recorded with
Digital Professional
Recorder (Roland R-26)
and a directional
microphone (Sennheiser
MKE600).
o Calls were analyzed
using SAP2011.
Results
Modes of uttering Loud calls in Phaner spp
“Kiu” call
Duet
Male call
Call Parameters measured:
Amplitude (dB); absolute deviation from zero.
Pitch; perceived tone of sound (measure of period of oscillation)
Mean frequency; assesses the center of the distribution of
power across frequencies.
Peak frequency; frequency of maximum power.
Goodness of pitch; estimate of harmonic pitch periodicity
Wiener entropy; measure of width and uniformity of power
spectrum
Frequency Modulation (FM); estimated based on time and
frequency derivatives across frequencies e.g. if freq derivatives
are higher than time derivatives FM is low.
Amplitude Modulation (AM); overall time derivative power
across all frequencies within a range. Captures changes in
amplitude envelope of sound.
Number of individuals and syllables measured
per site
Site
Species
Local Name
No. of
individuals
No. of syllables measured
Montagne
d’Ambre National
Park (MANP)
Phaner
electromontis
-
5
921
Analamerana
Special Reserve
(ASR)
P. electromontis
-
8
2686
Zombitse
National Park
(ZNP)
P. pallescence
“kitata”
9
2524
Zahamena
National Park
(ZaNP)
p. furcifer
“tantana”
6
3025
Manongarivo
Special Reserve
P. pariente
“valovy”
7
2217
35
11373
Total
-
ZNP5
ZNP3
ZNP7
ZNP4
ZNP6
ZNP2
ZNP9
ZNP1
ZNP8
MANP2
MANP5
MANP1
MANP3
MANP4
ASR1
ASR2
ASR7
ASR4
ASR6
ASR3
ASR8
MSR4
MSR5
MSR3
MSR7
MSR6
MSR1
MSR2
ZaNP1
ZaNP2
ZaNP6
ZaNP4
ZaNP3
ZaNP5
Percentage similarity
50
Phaner species
60
Phaner electromontis
Phaner pallescens
Phaner parienti
Phaner furcifer
70
80
90
100
Sites/Species
Dendrogram showing four clusters of fork-marked dwarf
lemurs
4
Mean freq
Peak_freq
MANP3
MANP1
Entropy
ZNP5
Goodness
ZNP4
ZNP7
ZNP6
AM Pitch
MANP2
MANP4
ZNP1
MANP5
ZNP9
ZNP3
ZNP8
FM
ZNP2
ZaNP6
ZaNP4
Amplitude
ZaNP3
ZaNP5
ASR7
ASR8
ZaNP2
ASR1
ASR2
ZaNP1
MSR3
MSR4
MSR2
MSR7
ASR6
MSR5
ASR3
MSR1
ASR4
MSR6
PC2
2
0
-2
-4
-2
0
PC1
2
4
PCA ordination of fork-marked dwarf lemurs call
parameters
EIGENVECTORS
EIGENVALUES
Eigenvalues and Eigenvectors in relation to PC1 and PC2 of PCA
Variables
PC1
PC2
Eigenvalues
0,695
0,218
% Variation
53,8
16,9
Cumulative % Variation
53,8
70,8
Amplitude
-0,554
-0,177
Pitch
-0,450
0,085
Mean Frequency
0,047
0,046
Peak Frequency
-0,035
0,125
Goodness of Pitch
-0,298
0,121
FM
0,600
-0,025
AM
-0,197
0,213
Entropy
0,003
0,936
Acoustic variation supports pelage coloration
findings and reflect species specificity.
Differences of loud call in four species of Phaner
are consistent with species status of other animal
groups (other primates, birds and frogs).
Given that the species live in different habitats,
acoustic adaptation hypothesis may explain the
evolution of differences in loud calls.
Differences in acoustic components may be
caused by genetic divergence which may lead to
changes in vocal production and perception
system.
12
Divergence in size and mass of laryngeal
structure, rate at which vocal cords open and close
as well as in control of muscles for breathing and
vocal production may explain acoustic differences
according to Source Filter Theory of Speech
Production.
Revealed specific differences of loud calls of
Phaner are linked to differences in vocalizationrelated neural network as found in squirrel
monkeys.
Specific acoustic adaptation to the environment,
genetic drift, founder effects and selection factors
may have played a role in the evolution of speciesspecificity in loud calls of Phaner.
Conclusion
Cryptic species of Phaner show specific and
conspicuous acoustic differences in loud call.
Acoustic fingerprinting may:
– be used as a noninvasive tool for species
diagnosis and discrimination in Phaner.
– offer an easy and inexpensive way to determine
species in the field and laboratory.
– provide practical means of monitoring biodiversity
of animal group in nature.
Acknowledgements
 African Earth Observatory Network (AEON).
 Primate Conservation, Incorporation (PCI).
 MEF, Madagascar.
 Field assistants.
Thank you for your attention