Name Studbook ID Gender Age Species Birth Place Location Exp

Supplementary table 1. Age class I: 5-9 years, age class II: 10-19 years, age class III: >20 years. Species S: Sumatran orangutan, species B: Bornean orangutan (Pongo pygmaeus), species h: hybrid. Birth place C: captive born, birth place W: wild born. Location GATI: Great Ape Trust of Iowa, USA, location AZ: Apenheul Zoo, the Netherlands, location BQC: Batu Mbelin Quarantine Center, Indonesia. Neophobia without presenter not tested at BQC. Individuals at BQC are not attributed with an ID number in the Studbook. Name Studbook ID Gender Age Species Birth place Location Exp Allie 2675 female 15 S C GATI 1,2 Katy 2248 female 20 h C GATI 1,2 Knobi 1733 female 30 h C GATI 1,2 Popi 1141 female 38 B C GATI 1,2 Azy 1616 male 31 h C GATI 1,2 Rocky 3331 male 5 h C GATI 1,2 Jose 2516 female 17 B C AZ 1 Radja 842 female 47 B W AZ 1,2 Sandakan1881 female 27 B C AZ 1,2 Silvia 833 female 44 B W AZ 1,2 Amos 2974 male 8 B C AZ 1 Karl 839 male 49 B W AZ 2 Willie 3055 male 7 B C AZ 1,2 Bolo female 14 S W BQC 1 Mutia female 17 S W BQC 1 Pesek female >25 S W BQC 1 Tila female 8 S W BQC 1 Abel male 8 S W BQC 1 Beckham male 7 S W BQC 1 Nando male 5 S W BQC 1 Robert male 5 S W BQC 1 Vewe male 6 S W BQC 1

Supplementary table 2. Experiment 1: repeated exposure of novel food; experiment 2: social influences on novel food; GATI = Great Ape Trust of Iowa (US); AZ = Apenheul Zoo (the Netherlands); BQC = BatuMbelin Quarantine Center. Experiment Location Food items 1 GATI Tortellini, green 1 GATI Kidney beans 1 GATI Date 1 GATI Basil 1 AZ Japanese leaf 1 AZ Mozarella 1 AZ Olive, black 1 AZ Tortellini, green 1 BQC Cheese 1 BQC Lime 1 BQC Olive, black 1 BQC Spinach 2 AZ Artichoke 2 AZ Mini spring roll 2 AZ Bitter melon 2 AZ Poffertje 2 AZ Shrimp 2 AZ Banana blossom 2 GATI Banana blossom 2 GATI Bitter melon 2 GATI Krupuk (Indonesian shrimp cracker) 2 GATI Pasta 2 GATI Rattan shoot 2 GATI Tomatillo