RELATIONSHIPS OF ARCHONTA

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RELATIONSHIPS OF ARCHONTA ALTERNATE VIEWS
ARCHONTA MONOPHYLY BAT MONOPHYLY (TRADITIONAL)
Single origin of flight in bats, gliding sister
group
(supported by morphology)
ARCHONTA MONOPHYLY BAT POLYPHYLY
Flight evolved twice?
(supported by neuroanatomy)
ARCHONTA POLYPHYLY
Flight evolved once, bats and dermopterans
unrelated
(supported by molecular data)
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BAT PHYLOGENY (gene sequence data)
Traditional suborders
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ORDER CHIROPTERA
Icaronycteridae Archaeonycteridae
Hassianycteridae Palaeochiropterygidae Suborde
r Yinpterochiroptera Pteropodidae
Rhinolophidae Hipposideridae
Megadermatidae Rhinopomatidae
Crasseonycteridae Suborder Yangochiroptera
Nycteridae Emballonuridae Myzopodidae
Mystacinidae Phyllostomidae Mormoopidae
Noctilionidae Thyropteridae
Furipteridae Natalidae Molossidae
Vespertilionidae
Eastern Hemisphere only
Worldwide
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ORDER CHIROPTERA Temporal distribution and
phylogenetic relationships (morphology and
gene sequences)
YINPTEROCHIROPTERA
YANGOCHIREROPTERA
From Rose Archibald, 2005
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Family Icaronycteridae
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Structure of bat wings
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Comparative structure of vertebrate wings
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Wing shape and flight dynamics
Wing aspect ratio (length/width)
Artibeus (low aspect ratio) Eumops (high
aspect ratio)
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Characteristics of sound
AMPLITUDE (loudness) 20 dB whisper 60 dB --
conversation 130 dB pain threshold Bat
echolocation 60 120 dB
1400 Hz (1.4 kHz)
FREQUENCY Human hearing 0.02 20 kHz Bat
echolocation 9 200 kHz
http//www.asel.udel.edu/speech/tutorials/acoustic
s/sn_h7.wav
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Characteristics of sound
ATTENUATION of sound (rate of energy
loss) Increases with frequency
ECHO attenuation Increases with frequency
HOWEVER Higher frequencies produce echoes
from smaller objects.
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Characteristics of sound in echolocation High
frequencies more effective in locating small
targets but have limited range Low
frequencies increase detection range but limit
resolution of target Constant frequency
(CF)allows for precise location via doppler
shift (i.e., returning sound has a shifted
freqeuncy) Multiple frequencies (broad band)
provide more information about target shape
Harmonics Frequency modulation (FM)
frequecny sweep
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Bat ear shapes
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Basic types of microchiropteran calls
Broad FM (frequency modulated harmonics)
FM (frequency modulated) Initial
CF (constant frequency) Teriminal FM
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Insulation from self-deafening
Isolation of the otic capsule from cranium
Dampening sound transmission through middle ear
ossicles Tensor tympani (increasing tension on
tympanum) Stapedius (regulates contact of stapes
with cochlea)
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Comparative morphology (size of cochlea)
CF
CF/FM
fossils
FM
no laryngeal

echolocation