Richard Byrne

Scottish Primate Research GroupUniversity of St Andrews

Parallel evolution of intellect?

The cognitive abilities of elephants

• I work in a psychology department, on the evolution of intelligence ….

• …it’s pretty obvious why I (usually) study non-human primates:

• Chimpanzees, gorillas, baboons, etc.

• Why study elephants?

What we know about elephant minds (2009)…Bates, L A, Sayialel, K N, Njiraini, N, Moss, C J, Poole, J H, & Byrne, R W (2007) Elephants classify human ethnic groups by odor and garment color. Current

Biology, 17, 1938-1942Bates, L A, Lee, P C, Njiraini, N, Poole, J H, Sayialel, K, Sayialel, S, Moss, C J & Byrne, R W (2008) Do elephants show empathy? Journal of Consciousness

Studies, 15, 204-225Bates, L A, Sayialel, K N, Njiraini, N, Poole, J H, Moss, C, & Byrne, R W (2008) African elephants have expectations about the locations of out-of-sight family

members. Biology Letters, 4, 34-36Chevalier-Skolnikoff, S, & Liska, J (1993) Tool use by wild and captive elephants. Animal Behaviour, 46, 209-219Hart, B L, & Hart, L A (1994) Fly switching by Asian elephants: tool use to control parasites. Animal Behaviour, 48, 35-45Hart, B L, Hart, L A, McCoy, M, & Sarath, C R (2001) Cognitive behaviour in Asian elephants: use and modification of branches for fly switching. Animal

Behaviour, 62, 839-847Irie-Sugimoto, N, Kobayashi, T, Sato, T, & Hasegawa, T (2008) Evidence of means-end behavior in Asian elephants (Elephas maximus). Animal Cognition, 11:359–

365Irie-Sugimoto, N, Kobayashi, T, Sato, T, & Hasegawa, T (2009) Relative quantity judgment by Asian elephants (Elephas maximus). Animal Cognition, 12:193–9Markowitz, H, Schmidt, M, Nadal, L, & Squier, L (1975) Do elephants ever forget? Journal of Applied Behavioural Research, 8, 333-335McComb, K, Baker, L, & Moss, C (2006) African elephants show high levels of interest in the skulls and ivory of their own species. Biology Letters, 2, 26-28McComb, K, Moss, C, Durant, S, Baker, L, & Sayialel, S (2001) Matriarchs as repositories of social knowledge in African elephants. Science, 292, 491-494McComb, K, Moss, C, Sayialel, S, & Baker, L (2000) Unusually extensive networks of vocal recognition in African elephants. Animal Behaviour, 59, 1103-9Nissani, M (2004) Theory of mind and insight in chimpanzees, elephants and other animals? In L J Rogers & G Kaplan (Eds), Comparative vertebrate cognition

London: Kluwer Academic/Plenum PublishersNissani, M (2006) Do Asian elephants (Elephas maximus) apply causal reasoning to tool-use tasks? Journal of Experimental Psychology, 32, 91-96Nissani, M, & Hoefler-Nissani, D (2007) Absence of mirror self-referential behavior in two Asian elephants. Journal of Veterinary Science, 1Nissani, M, Hoefler-Nissani, D, Tin Lay, U, & Wan Htun, U (2005) Simultaneous visual discrimination in Asian elephants. Journal of the Experimental Analysis of

Behaviour, 83, 15-29Plotnik, J M, de Waal, F B M, & Reiss, D (2006) Self-recognition in an Asian elephant. Proceedings of the National Academy of Sciences, 103, 17053-17057Poole, J, Tyack, P L, Stoeger-Horwath, A S, & Watwood, S (2005) Elephants are capable of vocal learning. Nature, 434, 455-456Povinelli, D (1989) Failure to find self-recognition in Asian elephants (Elephus maximus) in contrast to their use of mirror cues to discover hidden food. Journal of

Comparative Psychology, 103, 122-131Rensch, B (1956) Increase of learning capability with increase of brain size. American Naturalist, 90, 81-95Rensch, B (1957) The intelligence of elephants. Scientific American, 196, 44-49Wickler, W, & Seibt, U (1997) Aimed object-throwing by a wild African elephant in an interspecific encounter. Ethology, 103, 365-368

Evidently, we don’t know the full story about elephant cognition yet;Today, I’m just going to give a selection of intriguing findings, and hope to convince you that, on current evidence, elephants show a“parallel evolution of intellect”

Presented various items, bones and other things, where elephants would see them

Measured how long they showed interest in each

Karen McComb

“interest” in bones….do elephants understand death?

Can elephants ‘count’ in any way?

And if so, how do they do it?

• Just as good at picking the larger quantity when it was only slightly bigger (e.g. 6:5) than when it was much bigger (e.g. 5:1)

• Performance did not vary with the total number of items presented, up to 12

Tested elephants individually; subjects choose the basket with the most food.

Found…

items visible when choice made

items invisible when choice made

⇒No effects of ratio of two options, e.g. 4:5 versus 1:6, or total number of baits up to 12

⇒ High capacity working memory?

Understanding the problems of others

Do Elephants Show Empathy?Bates, L A, Lee, P C, Njiraini, N, Poole, J H, Sayialel, K Sayialel, S, Moss C J and Byrne, R W Journal of Consciousness Studies,15, 204-225 (2008)

You see yourself in a mirror…obvious enough, except:• Most animals don’t – they see someone else, and make

‘social responses’ at the ‘other animal’• After a while, they ‘habituate’ and ignore their image• Monkeys can use their hand’s image to reach accurately

where they can’t see directly, or notice in the mirror that others are approaching

• But only great apes (and probably dolphins) show signs that they know it’s me when they see themselves in a mirror

These researchers tested Indian elephants …

Understanding dangers

• Several species of animal known to respond appropriately to threats from different species of predator

• This implies they naturally classify the natural world into species (at least some species), like humans do

• Do they distinguish among different types of one species?

• Anecdotal data: attacks on Maasai cows (harmless, but associated with Maasai), suggests distinguish the Maasai

• Elephants rely more on olfaction: we compared elephants’ reaction to a garment worn by Maasaiman with one worn by Kamba

• If they get close, do they relate red colour to the Maasai threat? Compared red and white cloths, presented close.

• No quicker to react, but…• Move faster• Travel further• Take longer to relax

Comparing cloths worn by Maasai with those worn by Kamba, on scent cues

Detecting scent…

Retreating….

Bunching defensively….

Unworn red cloth, seen

Comparing reactions to red cloths versus white ones, neither worn

• Stronger reaction to red than white, but…• Aggression, not flight

InterpretationScent cues tell them no actual Maasai is present; so…Safe to show true feelings

Moving urine samples around!

Pick up sample….…then place in front of moving file of elephants

Compare:

Kin/non-kin (absent)Absent/present (kin)Ahead/behind (party member)

Elephants recognize kin on the basis of scent alone……and differences stronger when compare trunk reaches

Elephants recognize individuals (not just ‘kin-scent’)Elephants keep running track of the locations of 17+ females(probably more, since some males also socially relevant)⇒ high-capacity working memory

Elephant cognition• Individual recognition• Recognize self in mirror• Social empathy and helping• Keep track of kin, using mix of evidence• Number judgement• Subcategorize ‘human’• Distinguish ‘elephant’even after death• Exceptional working memory capacity• …and much yet to do!

AcknowledgementsMain collaborator: Dr Lucy BatesAmboseli Trust for Elephants, especially

Cynthia Moss, Program DirectorSoila Sayialel, Project ManagerKatito Sayialel and Norah Njiraini, Research AssistantsJoyce Poole, Harvey Croze, Trustees and advisorsPurity Waweru, Administrative Officer

Leverhulme Trust (funding for L A Bates)Friends and colleagues for help with images:

Naoko Irie-SugimotoKaren McCombJosh Plotnik