1. Enhedens navn
Welcome!

2. Institute of Biology, Section for Ecology and Evolution
DAILY PATTERNS OF GROOMING BEHAVIOUR
IN CHACMA BABOONS (PAPIO URSINUS)
Internal supervisor: Associate professor, DSc. Torben Dabelsteen
External supervisors: Dr. Guy Cowlishaw
PhD stud. Alecia Carter & Harry Marshall
Institute of Zoology, Zoological Society of London
A test of the biological market theory
Tsaobis Baboon Project - Namibia

3. TSAOBIS BABOON PROJECT
• Guy Cowlishaw
• Ecology & behaviour – Desert-adapted baboon population
• Since ~ year 2000
• Central Namibia – Tsaobis Leopard Park
• 2 PhD’s + 6 volunteers

4. PROGRAMME
Introduction
Methods
Results
Discussion
Conclusion & perspectives

5. • Care for/cleaning skin, fur, feathers etc.
• Behaviour in many animals
• Especially among primates
• Auto- vs. allo-grooming
• Function
Hygienic
Stress reducing
Social
• Cost
Time for other activities
Vigilance
WHAT IS GROOMING?
Introduction

6. WHY GROOM OTHERS?
Introduction
Altruism between relatives
• Kin selection theory (Hamilton, 1964)
• Factor of relatedness, r
• Hamilton’s rule: rB > C
Cooperation between non-relatives
• Reciprocal altruism (Trivers, 1971)
• Three conditions:
1) B (receiver) > C (donor)
2) High probability for future encounters
3) Receiver and donor remember each other -> behaviour reciprocated
Does the same behaviour need to be reciprocated?
Not necessarily!
?

7. THE BIOLOGICAL MARKET-THEORY
Introduction
• Primates-> social complex group-structure
• Many social interactions
• Seyfarth (1977), Nöe & Hammerstein (1994), Henzi & Barrett (1999)
• Grooming as currency
1) Can be reciprocated for itself
2) Can buy other ”services”
• Grooming can be exchanged for:
1) Access to infants
2) Support during aggression
3) Tolerance during feeding
• The market is dynamic
- Supply and demand
- The value of the service/commodity
- Individual characteristics

8. Rank diff.
Chacma baboons
Introduction
• Females stay in natal group
-> matrilines
• Adult males emigrate
• Strong linear dominance hierarchy
• Males fight for their rank
• Females inherit their rank from their mother
Alpha-male
Adult males
Matriline 1 (α-female, daughters/sons)
Matriline 2 (…)
Matriline 3 (…)
…
Lowest ranking female
Socially complex group-structure
Relatedness
Social bond
Sex, age, rank,
sociality
Sex, age, rank,
sociality

9. • Grooming buys tolerance -> Rank diff. btw. groom pairs greatest in the morning
• Family and ’friends’ exhibit tolerance -> groom more in the evening
• Tolerance’s value matches payment -> Greater effort in the morning when rank diff. is great
• Feeding competition raises the value of the tolerance
• Lowest ranking + social + older individuals negotiate more tolerance
It is not random, who grooms who at what time of day
PURPOSE, HYPOTHESES & PREDICTIONS
Introduction

10. STUDY AREA
Methods
• Swakop river
• Two habitat types
Semi-desert
Riparian
woodland

11. THE BABOONS
Methods
L (n=24) J (n=36)
• Two groups
• Habituated to observers
• Individually identifiable
L sleeping cliffs
J sleeping cliffs
J & L sleeping cliffs
Water holes
Camps

12. DATA COLLECTION
Methods
• May – November 2009
• Follow groups from dawn to dusk
• Training period
• 1 h. focal observations
- Behavioural state
- Dominance interactions
• 10 min. focal observations
- Events: Approach/retreat
- 5 m. distance
• Ad libitum dom. interactions

13. DATA SET
Methods
1 groom bout = groom activity btw. same pair; pause of max 10 seconds
• Individual + groom partner -> repeated observations
• Several groom bouts in the same observation
-> Data not independent
• Many predictors
• Interaction-effects
General linear mixed model (fixed + random effects)

14. MODELS
Methods
4 model categories
Model 1: Rank difference
Model 2: Relatedness
Model 3: Social bond
Model 4: Groom effort per bout
Groom pair of
1) all types of individuals
2) only adult females
Choice of
partner
?
?

15. PREDICTORS & STATISTICS
Methods
• Time of day, where the groom bout occurred
• Rank difference
• Relatedness
• Social bond
• Feeding competition
• Initiator’s rank, age & sociality
• Interactions – all variables with time of day
• Two statistical tests
1) Likelihood ratio test
2) Markov chain Monte Carlo test
Model with only the important factors
Only if not the response-variable

16. HOW MUCH TIME IS SPENT GROOMING?
Results
• 1780 hours focal observations (1 t. focal obs.)
• 1844 groom bouts
• Juvenile og adult females spend most time (14%) – sub adult males least (3%)
Forage
Travel
Rest
Allo-grooming
Drink
Play
Auto-grooming
All individuals (60)

17. DO PAIRS HAVE A HIGHER RANK DIFF. IN THE MORNING?
Results
YES!
• Estimate±SE: -0.008 ±0.004, P<0.01
• Not for adult female pairs
• Relatedness correlates positively (P<0.001)
Effect of other factors?
• Feeding competition: No
• Rank, age og sociality: No
Time of day
Rank difference
Model 1: RANK DIFFERENCE

18. DO RELATIVES GROOM MORE LATER IN THE DAY?
Results
NO!
• BUT … more in the morning
• Estimate±SE: -0.008 ±0.004, P=0.09
• Also among adult female pairs
Effect of other factors?
• Feeding competition: No
• Rank, age og sociality: No
Relatedness
Time of day
Model 2: RELATEDNESS

19. DO ’FRIENDS’ GROOM MORE LATER IN THE DAY?
Results
NO!
Effect of other factors?
• Feeding competition: No
• Age og sociality: No
BUT…
• Adult females: Daily pattern
affected by initiator’s rank, P<0.05
Only when the groom bout’s
initiator is the dominant
Model 3: SOCIAL BOND
Late
Early
High rank
Low rank

20. GROOM PARTNER CHOICE
Results
• The prediction about rank difference was correct!
• Mornings: Pairs with high rank diff. og relatedness
• No effect of feeding competition,
rank, sociality og age
BUT
• Within adult female pairs - effect of rank
-> when the dominant initiator’s rank is low
-> grooms with subordinate ’friends’ in the morning
?
?
Model 1-3: RANK DIFFERENCE, RELATEDNESS & SOCIAL BOND

21. IS THERE A GREATER GROOM EFFORT EARLY IN THE DAY?
Results
NO!
• But… greater later in the day
• Estimate±SE: 0.07 ±0.03, P<0.01
• Higher rank, less effort
Effect of other factors
• Feeding competition: No
BUT
The daily pattern depends on:
• Relatedness, when initiator is subord.
Time of day
Initiator’s groom effort
18 min.
2.5 min.
55 sec.
3 sec.
Model 4: GROOM EFFECT

22. GROOM EFFORT, WHEN INITIATOR IS SUBORDINATE
Results
Depends on relatedness (P<0.05)
• Close relatives
-> greatest effort in the morning
• Non-relatives
-> least effort in the morning
Influence of other factors?
• Large rank difference (P<0.001)
• Higher rank (P<0.05)
• Older (P<0.05)
Greater effort
Late
Early Closely
related
Not
related
Model 4: GROOM EFFORT

23. GROOM EFFORT
Results
• Generally smaller groom effort earlier in the day
• No extra effort in the morning with high rank difference
• Higher rank, smaller effort
• BUT - when initiator is the subordinate
-> greater effort when rank is higher
• No effect of feeding competition
• When the subordinate grooms a close relative
-> greater effort in the morning
Model 4: GROOM EFFORT

24. WHY GREATER RANK DIFFERENCE IN THE MORNING?
Discussion
• In accordance with the biological market theory
• More beneficial to negotiate tolerance earlier
• Why not negotiate tolerance the whole day?
1) A subordinate also has parasites!
2) Has costs
3) Risk of aggression
The choice of who & when is important!
Model 1: RANK DIFFERENCE

25. WHY NO DAILY VARIATION IN RANK DIFF. IN AD. FEMALES?
Discussion
They do not choose each other strategically during the day
• They do not negotiate tolerance with each other
• High competition for adult females
The value is high – it pays all day long
• Tolerance is returned over several days
Model 1: RANK DIFFERENCE

26. Tolerance is also negotiated between relatives?
• More beneficial in the morning
• Lower risk of aggression
• Better ’rate’
Greater benefits of getting groomed in the morning?
• Higher stress levels?
• More ecto-parasites?
WHY DO RELATIVES GROOM MORE IN THE MORNING?
DiscussionModel 2: RELATEDNESS

27. ?
WHO IS CHOSEN IN THE MORNING?
Close relative
High rank difference
Close relative
Model 1 & 2: RANK DIFFERENCE & RELTEDNESS

28. WHY NO DAILY PATTERN IN ’FRIENDSHIP’?
Discussion
• Tolerance is not negotiated between ’friends’
• More and closer social bonds -> higher fitness
BUT!
Why does a low ranking adult female
start to groom a subordinate ’girlfriend’
more in the morning?
• Competition for females/risk too high
• Females trades with e.g. males in the morning
• Special strategy: Use ’girlfriends’ to get groomed?
Model 3: SOCIAL BOND

29. WHY DOES FEEDING COMPETITION NOT HAVE AN EFFECT?
Discussion
• Feeding competition does not vary considerably
• Dispersal behaviour? Optimal exploitation of available food sources?
• Competition for partners -> Not an unrestricted choice!
• If tolerance is negotiated -> less aggression

30. WHY IS THE GROOM EFFORT LOWEST IN THE MORNING?
Discussion
• Does not support the hypothesis
HOWEVER
• Highest ranking individuals need to groom least
• Higher rank difference  greater effort for the subordinate
• At the bottom of the hierarchy  less effort  especially limited in time?
ALSO FOUND
• Both high relatedness and rank difference in the morning
 Groom bouts shorter in the morning (found!)
Mornings could be a hectic time
Model 4: GROOM EFFORT

31. EFFECT OF RELATEDNESS ON GROOM EFFORT
Discussion
• Generally lower effort in the morning
BUT…
• The daily pattern depends on relatedness, when the initiator is subordinate
WHY?
• Great effort  strengthens a social bond  important after a night?
• Tolerance negotiated between relatives  Beneficial in the morning
• Help a close relative removing parasites + reduce stress
It pays for a subordinate
to spend extra time in the morning
grooming a close relative
Model 4: GROOM EFFORT

32. WHAT DID I FIND?
Conclusion
Grooming in the morning
• High rank difference
• High relatedness
• Low groom effort
It is NOT random
who grooms who,
when and for how long
In accordance with the biological market theory!
 tolerance is negotiated with both dominants and relatives
 the baboons structure their choice in an optimal way during the day
New hypothesis - ’Groom-less-with-more’

33. ’GROOM-LESS-WITH-MORE’ IN THE MORNING?
Perspectives
• Optimises the benefit
• Bet on more individuals -> lower risk of losing all effort

34. FUTURE STUDIES
Perspectives
• MISSING LINK! Grooming in the morning  Tolerance later?
• What type of pair trade with each other in the morning?
• Higher stress levels and more parasites in the morning?
• Higher groom partner shift rates in the morning?

35. THANK YOU!GENERAL SUPERVISION
Torben Dabelsteen (DK)
Guy Cowlishaw (UK)
Alecia Carter (AU)
Harry Marshall (UK)
STATISTICS
Roger Mundry (GE)
Thorsten Balsby (DK)
Gösta Nachman (DK)
Michael K. Borregaard (DK)
Karina Banasik (DK)
DATA COLLECTION
Alecia Carter (AU)
Harry Marshall (UK)
Katherine Forsythe (AU)
Rebecca Bodenham (UK)
Will Symes (UK)
Jenie Iles (NZ)
Will Birkin (UK)
Hannah Peck (UK)
INSTITUTIONS
Institute of Biology, University of Copenhagen
Institute of Zoology, Zoological Society of London
Desert Research Foundation of Namibia
Namibian Ministry of Lands and Resettlement
Namibian Ministry of Environment and Tourism
OTHERS
Solveig Walløe Harpøth
Nana Hesler
Mikkel Bjelke Kristiansen
FINANCIAL SUPPORT
Carlsberg’s Fond for Studenterrådet ved Københavns Universitet
Ditlev Marcussen Buch og hustru Maren Buch, Baltzergaard Stiftelse
Friedrick Wilhelm Frank og hustru Angelina Frank’s Mindelegat
Greve A. Brockenhuus-Schacks Legat for den slesvigske ungdom
Grosser Wilhem Rackwitzs Legat
Hotelejer Anders Månsson og hustru Hanne Månssons Mindelegat
Kolding Gymnasiums Venner
Københavns Kommunes Legat for uddannelse mv.
Købmand Jørgen Sørensen og hustru’s fond
Oticon Fonden
Studiehjælpen Valdemar Shiøtts Minde
Thorkild og Thea Rosenvolds Legatfond