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Winterschlaf inA den Tropen:
Ein Kontinuum an Möglichkeiten
Kathrin H. Dausmann
Energy
Seasonal fluctuations



low temperatures
limited food availability
no open water
“Traditional“ daily torpor and hibernation
Heldmaier et al. Resp Physiol Neurobio 2004

controlled reduction of metabolic rate & body temperature

high energy savings (> 90%)
“Traditional“ daily torpor and hibernation
Hut et al. JCP B 2002

controlled reduction of metabolic rate & body temperature

high energy savings (> 90%)
Daily and seasonal fluctuations & unpredictability



N
D
J
O
F
M
S
A
rainy season (= summer)
Low temperatures
Limited food availability
No open water
A
J
J
M
dry season (= winter)
80
Ta max
35
30
70
60
25
50
20
40
15
30
20
pre
10
5
10
Ta min
0
January
0
June
precipitation (mm)
temperature (°C)
40
100 km
Daubentoniidae
Lepilemuridae
Lemurs
Cheirogaleidae
Phaner (4 species)
Cheirogaleus (6 species)
Allocebus (1 species)
Mirza (2 species)
Microcebus (16 species)
Lemuridae
Indriidae
Dense humid forest
Secondary complex
Dense dry forest
Mangrove
Savannah
Swamps
Cheirogaleus medius – Obligate hibernation
Fat-tailed dwarf lemur
Cheirogaleus medius
100 km
Cheirogaleus medius – Obligate hibernation
Cheirogaleus medius – Obligate hibernation
north
• Nocturnal, arboreal, 130g
• Frugivorous, insectivorous
• Social monogamy
• Defended territories
100 m
fat-tailed dwarf lemur
Cheirogaleus
Fat-tailed
dwarfmedius
lemur
males
Cheirogaleus medius
females
Dausmann, unpublished
Cheirogaleus medius – Obligate hibernation
Cheirogaleus medius – Obligate hibernation
temperature (°C)
40
30
20
10
0
time (days)

passive thermoregulation

strong daily fluctuations (up to 30°C)
Tb male
Ttree tree hole
Ta outside
Cheirogaleus medius – Obligate hibernation
Increasing insulation of tree hole

Fluctuating, very flexible
patterns of Tb and MR
Marmota marmota
Arnold Ver. Dtsch. Zool. Ges. 1993
Dausmann et al.
Nature 2004
JCP B 2005
Cheirogaleus medius – Obligate hibernation

Fluctuating, very flexible
patterns of Tb and MR

Energy savings
independent of
hibernacula choice
Energy savings = 70 %
Tb min = 9.3 °C
Dausmann et al. JCP B 2009
Cheirogaleus crossleyi and C. sibreei – Underground hibernators
100 km
Marina Blanco
Cheirogaleus crossleyi and C. sibreei – underground hibernators
400/300 g
high altitude habitat (Ta < 0°C)

underground hibernation
(5 months )

~ constant Tb with arousals
Cheirogaleus crossleyi and C. sibreei – Underground hibernators
400/300 g
High altitude habitat (Ta < 0°C)
40
Temperature (°C)
35
30
25
20
15
10
5
0
Energy savings = 86/89 %
Tb min = 7.5/10.5 °C
Days

Underground hibernation
(5 months )

~ Constant Tb with arousals
Blanco et al., unpubl. data
Cheirogaleus – Obligate hibernation

All dwarf lemurs obligate
hibernators

„Wie man sich bettet, so
schläft man.“
Microcebus griseorufus – Physiological flexibility
100 km
50 g
Very seasonal, unpredictable habitat
(spiny forest)

physiological flexibility
Susanne Kobbe
Microcebus griseorufus – Physiological flexibility
Daily torpor
temperature (°C)
temperature (°C)
Occasional torpor
days
temperature (°C)
temperature (°C)
days
days
Prolonged torpor
days
Kobbe et al. JCP B 2011
Continuous hibernation
Microcebus griseorufus – Physiological flexibility
Daily torpor
temperature (°C)
temperature (°C)
Occasional torpor
days
temperature (°C)
temperature (°C)
days
days
Prolonged torpor
days
Kobbe et al. JCP B 2011
Continuous hibernation
Microcebus griseorufus – Physiological flexibility
2014
Daily torpor
temperature (°C)
temperature (°C)
Occasional torpor
2014
days
Prolonged torpor
days
temperature (°C)
temperature (°C)
days
2014
2015
days
Kobbe et al. JCP B 2011
Continuous hibernation
Microcebus griseorufus – Physiological flexibility
Downwards shift of lower critical temperature during
normothermia
Summer
TTlclc Summer
Tlc Winter
Tlc Transition period
7.5°C
Jack - and master - of all trades: the Cheirogaleidae
50
0
100 km
5 months
hibernation
7 months
hibernation
torpor,
hibernation
Antananarivo
Morondava
Ranomafana
Tulear
Fort Dauphin
torpor,
hibernation
3 months
hibernation
Kirindy
Dense humid forest
Secondary complex
Dense dry forest
Mangrove
Savannah
Swamps
5 months
hibernation
4 months
hibernation
torpor,
hibernation
Jack - and master - of all trades: the Cheirogaleidae
• Very seasonal

climatic differences
• Very arid
• Very unpredictable
Jack - and master - of all trades: the Cheirogaleidae

climatic differences

strategy depended on body condition
Kobbe et al. JCP B 2011
Jack - and master - of all trades: the Cheirogaleidae

Climatic differences

Strategy depended on body condition

Different reproductive patterns
2x per year
Reproduction
Lifetime
Reproduction
Lifetime
once every
2 years
100 km
Galagos
Lorises
Daubentoniidae
Lepilemuridae
Lemurs
Cheirogaleidae
Phaner (4 species)
Cheirogaleus (7 species)
Allocebus (1 species)
Mirza (2 species)
Microcebus (16 species)
Lemuridae
Indriidae
Dense humid forest
Secondary complex
Dense dry forest
Mangrove
Savannah
Swamps
Galago moholi – Torpor as emergency strategy
 Only 25% of individuals

 Only subadults, mostly males


 Singular occasions

 Not routine seasonal adjustment
Julia
Nowack
Nowack et al. PLoS ONE 2010
Afrotropical heterothermy – a continuum of possibilities
Rare Use of Heterothermy
Obligate Hibernation
2x per year
Gestation:
120d
60d
once every 2 years
60d
60d
Conclusion
Primate species do enter torpid states, even in climates
considered tropical
Extent of heterothermy varies between closely related
species, within species, for individuals of one
population, or for individuals during different years –
reflecting ecological and evolutionary forces
Physiological flexibility particularily important for species
living in less predictable habitats  climate change?
Commission Tripartite, Ministère pour la Production Animale, Département des Eaux et Forêts and
ANGAP/MNP of the Malagasy gouvernment
Université d'Antananarivo (Département de Biologie Animale, Département
d'Anthropologie et de Biologie Evolutive, Département de Biologie et Ecologie
Végétale: Prof. Dres. Berthe Rakotosamimanana, Daniel Rakotondravony, Olga
Ramilijaona, Charlotte Rajeriarison, Edmond Roger)
Parc Botanique et Zoologique de Tsimbazaza
Centre de Formation Professionnelle Forestière de Morondava
Deutsches Primatenzentrum, Prof. Dr. Peter Kappeler, Dr. Rodin Rasoloarison, Léonard Razafimanantsoa
Alpha from Marofandilia, Dr. Joanna Fietz, François from Marofandilia, Peggy Giertz, Dr. Julian
Glos, Jean-Claude from Beroboka, Dr. Jutta Schmid, Tina Stahl, Christine Wiedemann
Prof. Dr. Gerhard Heldmaier
Prof. Dr. Jörg Ganzhorn
Deutsche Forschungsgemeinschaft
BMZ/GTZ
Deutscher Akademischer Austauschdienst
WWF Germany and WWF Madagascar
Thank you for your
attention and for not
entering torpor during this
talk!
"It is well known that within the
tropics, the hybernation, or more
properly aestivation, of animals is
determined not by the temperature,
but by the times of drought".
The Voyage of the Beagle