Evidence of means–end behavior in Asian elephants

1. Evidence of means–end behavior in Asian elephants Irie-Sugimoto, N. · Kobayashi, T · Sato, T ·Hasegawa, T

2. Introduction • Elephants are believed to be intelligent • Most data is anecdotal; not much empirical

3. Studies that support intelligence in elephants • Memory studies • Rensch (1957) showed memorization of “correct” pictures • McComb et al (2000), showed elephants remembering contact calls of other elephants • Skillful tool use • Hart et al (2001) & Hart and Hart (1994) recorded spontaneous tool use in wild elephants

4. Further Research • Studies that oppose intelligence in elephants • Nissani (2006) showed failure at basic reasoning • Maybe the reasoning is neuronal! Larger and less densely packed cortical nonsomactic neurons (Hart et al, 2007) • Physiological/Anatomical reasoning • EQ (encephalization quotient) • Cortex to body ratio; a higher EQ “theoretically” relates to higher cognitive abilities (Jerison, 1974) • Part of the reasoning behind the study • Elephants have a high EQ, thus they should be able to do this experiment • Prehensile trunk is comparable to primates’ hands

5. Means-End Behavior • Used a Piagetian ‘support’ task • Came from child development research • Placing a toy on a towel, seeing if child would pull towel towards themselves to get the toy (~11 mos) • Shows: • Knowledge about relationship between means and ends • Spatial relationships between the two • Indicates development of cognitive processing of a definite goal and persistence in achieving goal

6. The ability is also shown in: • Nonhuman primates: New World monkeys; chimps; Cotton Top Tamarins • Other mammals: marmosets; dogs • Birds: pigeons and ravens

7. Methods – Basics • Two female Asian elephants (Elephus Maximus) • Authai (6) • Surya (10) • Four Experimental Conditions • Similar nuanced procedures • Elephants were brought to testing area • Two cardboard trays present • Chain between elephant and trays • Trials given in 5-day blocks with 10 trials per day

8. Methods – Analysis Basics • Significance of performance predetermined at 66% correct • Though given trials until reached ≥ 75% correct • Proceeded to next condition after obtaining ≥75% • All two-tailed binomial distributions Spreadsheet

9. Methods - The Four Conditions

10. Results – Condition A • Training condition • Pulling the cardboard tray with the bait. • They were given only one chance to select the right tray. • Authai had to be taught to select the correct tray first, Surya spontaneously pulled it. • Both achieved ≥66% on block 1 • Authai needed 2nd block to reach predetermined significance

11. Results – Condition B Spreadsheet Authai achieved 80% correct at third block of testing. Surya achieved 80% at the fifth block. This suggests they’re learning. Try to posit more meaningful results:

12. Results – Condition C • Authai • Performed significantly above chance in the first block. • Reached criterion by block 2 • Results suggest a transference of knowledge. • Surya • Performed poorly • Researchers attributed this to “low motivation” and removed her from the experiment.

13. Results – Condition D Performed above chance in each condition Second block to reach performance significance Researchers state this shows an understanding of spatial relationships between the tray and bait. Inconsistencies:

14. Discussion Overall conclusion: results show an understanding of means-end relationships and not just discrimination tasks. Performance shows a transference of knowledge between tasks. Results were not comparable to non-human primate performance in similar tests. Limitations including: sample size, motivation, visual cues.