Cláudia Sousa Memorial Fund

For the Advancement of Portuguese Primatology

Final Report

2018

Grant by: Prof. Tetsuro Matsuzawa

Supervisor: Prof. Misato Hayashi

Tutor: Raquel Costa

Recipient: Evelina Daniela Rodrigues

ii

Acknowledgements

I would like to express my gratitude to Professor Matsuzawa for the Claudia Sousa

Memorial Fund for the Advancement of Portuguese Primatology initiative, and to the

Japan Society for the Promotion of Science for the financial support: JSPS Core-to-core

A. (CCSN to Prof. T. Matsuzawa). I would also like to thank Professor Misato Hayashi,

Raquel Costa and Renata Mendonça for their advice, guidance and patience. I am

particularly grateful for the assistance given by Daniel Schofield and Professor

Catherine Hobaiter, that, even though they were working in the other side of the world,

they gave me continuous support by email and skype regarding the Bossou Archive

Project and my training, respectively. Many thanks to all the people I’ve the pleasure to

meet and work with during my stay in Japan. Thanks to Professor António José dos

Santos and to ISPA for encouraging my application to this initiative. Finally, a special

thanks to Professor Cláudia Sousa for her inspiration and legacy.

iii

Table of contents

Cláudia Sousa: the legacy ............................................................................................. 1

Primatology at Inuyama: Japan Monkey Centre and Primate Research Institute ............ 4

Japan Monkey Centre ................................................................................................ 4

Primate Research Institute ......................................................................................... 5

Seminars, workshops, courses and other events ......................................................... 5

Comparative Cognitive Science Course ................................................................. 6

Science Communication Course Workshop ............................................................ 8

Nerd Nite ............................................................................................................... 9

Travelling: Field sites and conferences ........................................................................ 10

The 10th

International Symposium on Primatology and Wildlife Science.............. 10

Koshima and Cape Toi ......................................................................................... 12

Jigokudani ........................................................................................................... 13

Kumamoto: SAGA (Support for African/Asian Great Apes) symposium and

Kumamoto Sanctuary ........................................................................................... 15

Bossou video archive .................................................................................................. 18

Labelling ................................................................................................................. 19

Digitising ................................................................................................................ 20

Splitting................................................................................................................... 21

Greeting Report .......................................................................................................... 22

Introduction ............................................................................................................. 22

Methods .................................................................................................................. 23

Defining greeting and leave-taking....................................................................... 23

Subjects and Field Site ......................................................................................... 24

Structuring the behavioural repertoire for greeting events .................................... 25

Data coding and analysis ...................................................................................... 26

Results .................................................................................................................... 27

Greeting events .................................................................................................... 27

Reciprocal greetings............................................................................................. 27

Leave-taking events ............................................................................................. 27

Discussion ............................................................................................................... 28

References .................................................................................................................. 31

1

Cláudia Sousa: the legacy

Professor Cláudia memory and work is alive through her students and colleagues - the

people who knew her well, but also by the people she inspired. I am one of those

persons. I never meet her directly, but I was deeply inspired by her work and I knew she

was the example to follow when I decided to engage in Primatology.

Professor Cláudia was the only Portuguese primatologist that has specialized in

primate cognition trough the study of wild and captive chimpanzees. My main field of

interest is language evolution trough a comparative approach of the early

communicative gestures in humans and in our phylogenetic closest relatives. During my

master thesis I had opportunity to collect data in human infants and to compare with

chimpanzees’ data reported in the literature. I think that if Professor Cláudia was alive,

she would be for sure one of the best researchers to supervise my work.

Having a BSc degree in Evolutionary and Developmental Biology and a MSc

degree in Cognitive Sciences, I can find some similarities in my early academic steps

with Professor Cláudia. Professor Cláudia started her academic path by studying

biology with a later specialization in human evolution. The cognition in our closest

phylogenetic relatives kept her attention, but studying that issue in our country seemed

difficult. Her persistence led her to endorse a PhD in the Primate Research Institute of

Kyoto University (KUPRI) under the supervision of Professor Matsuzawa.

Since 2001, Professor Cláudia Sousa lectured at Faculdade de Ciências Sociais e

Humanas da Universidade Nova de Lisboa (Portugal). She also had an active role in

several scientific societies and associations such as APP (Portuguese Primatological

Association), SPE (Portuguese Ethological Society), and CRIA (Center of Research of

Anthropology). Beyond her activism in boost the primatology status in Portugal, her

scientific work was what really inspired me. Her main fields of interest were primate

cognition and conservation.

Since her PhD, Professor Cláudia outlined her academic path trying to better

understand tool-usage by captive and wild chimpanzees. Some cognitive features are

more difficult to observe in the wild, but the excellent facilities in the Sky lab of KUPRI

allow researchers to do significant progresses in this field of research. In captivity

Professor Cláudia had the opportunity to explore the symbolic capacity of chimpanzees

through the use of tokens (Cláudia Sousa & Matsuzawa, 2001; Cláudia Sousa,

2

Figure 1. Cláudia Sousa at Primate Research Institute

Okamoto, & Matsuzawa, 2003) (Fig.1). In her research, she was particularly interested

in clarifying if chimpanzees can use tokens as tools to get a food reward and, if it was

efficient enough to maintain the chimpanzees’ motivation in performing a

discrimination task (Cláudia Sousa & Matsuzawa,

2001). With this study, Professor Cláudia showed

that chimpanzees were able to use a saving

behaviour to plan future actions. Later, she

analysed the behavioural and cognitive

development in a matching-to-sample task and

token use by an infant chimpanzee reared by her

mother (Cláudia Sousa et al., 2003). Professor

Cláudia noted that the learning process, in which

the infant have acquired the new skills respecting

this particular task, appeared to be similar to the

learning processes described in wild

chimpanzees: close observation of the mother for

extended periods of time; strong motivation for

copying the behaviour; and high levels of tolerance from the mother. The symbolic

concept, inherent to the use of tokens and their intergenerational transmission through

observational learning, opens several doors in the cognitive current research. In the

wild, Prof. Cláudia deepened this issue by describing different forms of tool use in

Bossou (Biro et al., 2003; Claudia Sousa, Biro, & Matsuzawa, 2009). Under the

supervision of Prof Matsuzawa, the Bossou community of chimpanzees in Guinea have

been studied for decades. A natural outdoor ‘laboratory’, had been created in the forest

to study their stone tool use, and Professor Cláudia gave important contributions to this

research. KUPRI has over 30-years of high quality video footage from this community,

where filming conditions are ideal. As professor Cláudia’s contributions to the study of

intergenerational learning processes involved in the use of tokens by captive

chimpanzees, these videos can serve as a unique window onto their communication

across multiple generations in the wild, allowing us to better understand the

controversial role of social learning in communication.

Also in the cognitive domain, Professor Cláudia was involved in some

innovating research that have shown that food sharing is not so infrequent in

3

Figure 2. Cláudia Sousa in the field

chimpanzees (Hockings et al., 2007) as previously though. Moreover, researchers have

realized that food sharing plant between unrelated individuals could be used as a social

tool for nurturing alliances and social bonds.

The conservation status of chimpanzees

was also a major concern of Professor Cláudia

(Casanova & Sousa, 2007; Gippoliti, Embalo, &

Sousa, 2003) (Fig. 2). The relations between

humans and chimpanzees needed to be evaluated to

understand the best conservational measures to be

taken. When studying these interactions in

Cantanhez National Park in Guiné-Bissau,

Professor Cláudia and colleagues realized that

chimpanzees of this area were being forced to

human intrusion in the forest and consequently the

human-chimpanzee negative interactions seemed to increase. The authors suggest that

the conflict levels could be minimized with novel strategies such as the alternative

income-generating projects and enrichment planning, involving the local communities

(Hockings & Sousa, 2013). Therefore, there is also an important legacy in the

conservation of wild chimpanzees left by Prof. Cláudia that deserve major attention.

It is difficult to summarize all of Professor Cláudia’s contributions to

primatology. I suppose there are many more contributions than those herewith

described, especially the contributions hidden behind the students that she was able to

thrill with her passion. Throughout different means, Professor Cláudia was able to come

closer to her students and to inspire others that didn’t have the opportunity to meet her.

In my particular case, Professor Cláudia inspired me to pursue my dream of studying

the cognitive processes inherent to communication. The opportunity to observe and

experience the laboratory work conducted by some of the leading experts in the field, as

well as attending the field courses and training programmes available at KUPRI, will be

determinant to become a more fulfilled researcher.

4

Figure 3. Bolivian Squirrel monkey at JMC Figure 4. Geoffrey’s spider monkey at JMC

Primatology at Inuyama: Japan Monkey Centre and Primate

Research Institute

Japan Monkey Centre

On the 17th September 2018 I had opportunity to visit the Japan Monkey Center (JMC).

This Centre was founded in 1956 and it is located in Inuyama, near the Primate

Research Institute. JMC it is not a regular Zoo, because it is also considered a museum

specialized in non-human primates. This Centre exhibits the largest number of

nonhuman primate species in the world: around 950 individuals from more than 60

different species. JMC is divided into several sectors, including some open-air

enclosures, where visitors can enter and observe the primates without any physical

barrier, such as the Wao Land with ring-tailed lemurs, and the Squirrel Monkey Land

with Bolivian squirrel monkeys (Fig. 3). The Monkey skyway allows the observation of

the Geoffrey’s spider monkeys moving across a 100-meter-long suspension bridge (Fig.

4).

We can observe different species of lemurs (brown lemurs, black lemurs and

ruffed lemurs) in the Madagascar House. The Africa Centre give us the opportunity to

see the lowland gorilla and mandrills. Some new world monkeys, such as Callitrichids

and Pithecids, can be found in the South American House. The Asian House has some

langurs and different species of macaques. There are also other outdoor enclosures such

as the Castle of Baboons (Anubis baboons) and the Monkey valley where a large group

of Japanese Macaques lives.

The museum is also an important part of this Centre. More than 6,300 specimens’

remains (skeletal, formalin-preserved brains, organs and parasites) are in the museum

database Captive Primate Collection (CAPriCo). “Primates”, the oldest scientific

5

Figure 5. CICASP seminar

journal focused on primatology, was published for the first time in 1957 by the JMC.

The museum section of JMC is still responsible for delegate editorial board

members/advisory board members/editor-in-chief, host editorial board meeting, and

editorial operation of the journal Primates.

Primate Research Institute

The Primate Research Institute of University of Kyoto (KUPRI) was founded in 1967

by Dr. Imanishi and his colleagues at Inuyama, where the Japan Monkey Centre was

already established. This Institute played a crucial role on the development of different

fields of primatology such as ecology, behaviour, cognition and evolution. In 1978, a

special focus was given to the subject of Comparative Psychology with the elaboration

of the “Ai project”. Within the scope of this project, Dr. Kiyoko Murofushi, Dr. Toshio

Asano, Dr. Tetsuya Kojima and Dr. Tetsuro Matsuzawa aimed to a better understanding

of the perceptual and cognitive basis of language-like skills.

The study of non-human primates in wild habitats was still important, therefore,

in parallel with the studies conducted in captivity at KUPRI, several research teams

were collecting data in the wild: Japan and even overseas in Africa (e.g., Bossou,

Mahale, Wamba, Kalinzu and Kahuzi).

Seminars, workshops, courses and other events

PRI promotes international collaborations to bring together senior and young

researchers, to contribute for a new generation of skilled experts in several areas of

Primatology.

The Centre for International

Collaboration and Advanced Studies in

Primatology (CICASP) provides

support on research and education

focusing on the primate mind, body,

ecology, conservation and genome. For

this purpose, this Centre is responsible

for the integration of a group of

6

international students and professors. Several seminars, workshops and other events, are

organized by CICASP, which often invite international collaborators. When it was

possible, I attended several weekly seminars (Ecology and Psychology on Tuesday, and

CICASP on Wednesday) (Fig. 5).

At PRI there is also the PWS program (Leading Graduate Program in

Primatology and Wildlife Science) that gives opportunity to Japanese and international

students conducting their master and PhD projects under KUPRI supervision. This

program includes several courses in different research areas, such as wildlife, genome,

comparative cognition and welfare. From the seminars, workshops and events that I

attended during my stay at PRI, I will give a special emphasis on the Comparative

Cognitive Science Course; the Science Communication Course Workshop; and the first

Nerdnite organized at Inuyama.

Comparative Cognitive Science Course

Main host: Prof. Masaki Tomonaga, Professor at Primate Research Institute, Kyoto university;

10-12 September 2018

The Comparative Cognitive Science Course allow students to get familiarized with the

cognitive experiments conducted at the Primate Research Institute. We had opportunity

to see the ongoing research with chimpanzees in two different labs, and the experiments

that are being conducted with horses near Inuyama.

During the first day (10th September) we visited Tomonaga sensei lab and we

saw a set of experiments that aimed to test motion perception, size and colour

discrimination through a touchscreen interface (Fig. 6). There was also a matching task

with humans’ faces that aim to test how parts of the faces can be used to recognize

unfamiliar and familiar subjects. An eye-tracking experiment was also occurring after

chimpanzees completed the touchscreen experiments (Fig. 7). The chimpanzees tested

during this afternoon were Pendesa, Gon and Ai.

We were able to see the same experiments during the morning of the following

day (11th

September), but with different chimpanzees: Cleo, Chloe, Pal and Popo. Two

different experiments were also tested in some of these chimpanzees: spatial perception

with chess pattern squares, and the reaction time to emotional vs. neutral facial

expressions in chimpanzees. The afternoon session was on Adachi sensei lab. We saw

the performance of Chloe and Ai in some experiments about categorical perception. The

7

Figure 8. Cognitive experiment in horses using touch screens

Figure 9. Riding experience

Figure 6. Cognitive experiment in chimpanzees using touch screens

Figure 7. Cognitive experiment using eye tracker

main tasks were focused on colour and sound association, in which black, white or

different scales of grey are matched with low or high pitch sounds.

The last day of the course (12th September) was dedicated to the horses

experiments that took place near Inuyama (Fig. 8). Professors Tomonaga and Adachi

were testing categorical perception with 3 different subjects, using touch screens

divided into two parts. Three different conditions were tested, in which two images

appear, one at each side of the screen (horse vs. cat): a) coloured pictures, b) grey scale

pictures and c) inverted pictures. Before coming back to the PRI, we had the

opportunity to ride the horses (Fig. 9).

In addition to these 3 days of the course, I had the opportunity to visit

Matsuzawa-sensei lab for other 3 days (18-20 September). The chimpanzees tested in

these 3 mornings were Ai, Cleo and Chloe. During the last morning, Ayumu also

performed the touchscreen experiments in a parallel session with Ai. There were around

8

Figure 10. Advertisment for the Schience Communication workshop

Figure 11. Dr. Margaux Phares during the first workshop session

10 different tasks all related with number order and memory. The complexity level

varied along the tasks and even within the same task to keep a high level of motivation.

Although I have studied Cognitive Sciences during my master, research on non-

human animals were not considered so often, and just theoretical aspects have been

mentioned during my master’s degree. Therefore, this course was a great opportunity to

see and experience the experimental basis of the comparative cognition research.

Science Communication Course Workshop

Dr. Margaux Phares, Science Communication Fellow at Hiroshima University

10/12 September 2018

During the first week I attended a workshop

entitled: “From field to front page: Science

communication and you” (Fig. 10). The

workshop was held at the large conference

room and was hosted by Prof Andrew

Macintosh.

During the first session (10th

September, Fig. 11) Dr. Margaux Phares had

the opportunity to introduce herself and to talk about the 3 basic rules in science

communication: “1. Know your audience”; “2. Respect your reader” (using clear

language and providing enough background); and 3. “Commit to a beginning, a middle

and an end”. We analysed two articles, targeted to different audiences, about the

discovery of a new atomic element found in Japan:

Nihonium. In the end we also heard a podcast

about the same topic, and together we discussed

the main differences with the other two previous

articles. In the end, Dr. Margaux Phares presented

some tools that are very useful in science

communication: Google scholar alerts; Google

news alerts; Youtube; Facebook; Instagram; and

Twitter.

The second session (12th September) was focused on Press Release articles and

News articles. We did a practical exercise on two articles about a surgical probe that

was able to detect cancerous cells (one press release article and one news article). The

9

Figure 13. Advertisemnt for the first Inuyama’s Nerd nite

Figure 12. Organizing comitee and speakers of the first Nerdnite at Inuyama

Press Release articles are written by press officers and their audience are journalists and

other media workers. The scientific content should not be too detailed, but enough for

journalists to write an article. The News articles are written by journalists and targeted

to people interested in science. The content could have the same degree of detail, and

contrary to the press release article do not need to have a neutral tone, as should be

interesting enough to attract readers attention. The editorial process behind the

publication of a News article can be summarized in the following steps: scientific

journal accepts paper and notifies researchers of embargo; press officers interviews

researchers; journalist reads press release and contact press office; journalist writes the

news article.

Nerd Nite

29 November 2018

Nerd Nite is an event held in more than

100 cities in the world, where colleagues

and friends gather to learn about different

scientific topics in a fun and casual

environment, while the audience enjoys

food and beverages. Usually there is a

specific topic and the presenters give

short talks (15-20 minutes) about the

topic of that Nerd Nite.

I had the pleasure to do part of the organizing

committee of the first Nerd Nite in Inuyama (Fig. 12). The

event was held at the PRI’s cafeteria on the 29th November

around 6 p.m. The topic of this Nerd Nite was "Always

look on the Bright Side of Death" (Fig. 13). The event

counted with the participation of 4 speakers (Josué

Pastrana, André Gonçalves, Sota Inoue, Hugo Reyez-

Centeno) and different fun activities such as dance

workshop, Karaoke and Interludes of death.

10

Figure 14. Group Photograph of all the participants at the PWS symposium

Figure 15. Poster presentation at the PWS symposium

Travelling: Field sites and conferences

The 10th

International Symposium on Primatology and Wildlife Science

Kyoto University

22-24 September 2018

The PWS Symposium started

with a special opening session

regarding the WRC 10th

anniversary (Fig. 14). On this

afternoon there was a session

about field and laboratory

studies on primates, a session

with invited talks by new PWS

members, and a final session

about Enrichment studies. The

sessions on the second day included studies on some primate species such as slow-loris

and bonobos and on non-primate animals such as elephants, penguins and koalas.

The “Workshop on Science Communication:

Mobile Filmmaking” took place in the congress room

from 1pm-4pm. This workshop was led by Dr.

Wiebke Finkler and Prof. Lloyd Spencer Davis. The

goal of the workshop was to give tools to researchers

to create engaging multimedia content for public

communication. There was a special focus on

Storytelling and other elements required for effective

science communication. Additionally, technical

details were also discussed regarding video

production and edition.

11

Figure 15. Group photograph after the Conserv’ sesssion

The poster session took place in the evening of the first and the second day of

the congress (abstract below) (Fig.14). There were 25 posters and I presented a poster

entitled: Social Grooming in rescued chimpanzees: how early social disruption and time

of rehabilitation affect sociality.

There were 3 more sessions

during the morning of the last day

of the congress, including 3 poster

award presentations. The second

session was about field and

laboratory studies. In the afternoon

there was a Conserv’Session

Abstract: Rescued chimpanzees living in sanctuaries may have their social skills

impaired due to their traumatic past. Often these chimpanzees were single-housed,

and they came from pet or entertainment industry. Grooming is a complex social

activity that plays a crucial role in the maintenance of social relationships. Therefore,

the monitorization of this behaviour in sanctuaries could be a good indicator of the

welfare and sociality vised in a rehabilitation process. The aim of this study was to

analyse how grooming varies according to: origin (wild or captive), past

circumstance (pet, entertainment or mixed), previous social housing (single-housed

or social-housed) and time of rehabilitation (up to or more than 10 years). For 138.8

hours, we recorded the duration of grooming in 13 adult chimpanzees living at

Fundació Mona . Our results indicate that past circumstance and previous housing

condition do not affect grooming duration, but chimpanzees born in captivity had a

higher duration of grooming than chimpanzees born in the wild. Moreover,

chimpanzees experiencing more time of rehabilitation have groomed more than

chimpanzees that arrived at Fundació Mona more recently. In conclusion, the higher

duration of grooming seems to be a positive consequence of the success of the

rehabilitation process. The rehabilitation time may attenuate the differences in

grooming duration that may have been caused by the social disruption factors such as

past circumstance and previous social housing. Nevertheless, the different

environments in which they have been born seems to still influence the duration of

grooming in the individuals of Fundació Mona.

12

Figure 16. Feral horses at Cape Toi. Figure17. Japanese macaques feeding at Koshima.

hosted by Prof Fred Bercovitch, where two documentaries about giraffes were

presented: Giraffe: Africa’s Gentle Giants and Last of the Longnecks. The scientific

content of these documentaries was commented by Prof. Bercovitch, Prof. Davis and

Dr. Finkler that also gave their opinion about more technical issues related to the video

production and edition (Fig. 15).

Koshima and Cape Toi

29 October – 1 November 2018

During my internship I had opportunity to spend two full days at the birthplace of

Japanese Primatology: Koshima. Six decades ago, Professor Imanishi was conducting

his studies on horses around this area, when they unexpectedly met a troop of wild

Japanese monkeys. In 1948 Prof. Imanishi conducted the first observational study on

Japanese monkeys. Some years later they reported the sweet-potato washing behavior,

founding evidence of proto-culture in Japanese monkeys. Fortunately, I was able to visit

Koshima from 29th October to the 1st November with Raquel Costa and Renata

Mendonça. We were hosted by Suzumura-san at the Koshima Field Station. This Field

Station was built in 1968 and is located in the opposite side across the sea from

Koshima Island.

On the first day, due to poor weather conditions, it was dangerous to cross the

sea to get to the island, so we visited Cape Toi instead. Cape Toi, located in the south of

Miyazaki Prefecture at the tip of Shibushi Bay, is known by the great amount of feral

horses living there (Fig. 16). We were lucky to have a horse expert among us, as Renata

Mendonça is conducting her research on horses in Portugal. Cape Toi’s horses live in

small groups when compared to the ones in Portugal, possibly due to the low risk of

13

Figure 18. Japanese macaque on the top of the scale

Figure 19. Infant japanese macaque

predation. We also had the opportunity to go to the visitor centre that had more

information about the horses living there, but also about horses around the world.

On the second day we visited the Koshima Island, where the macaques live in

two groups with more than 40 individuals each. We arrived at the small beach where we

had the chance to observe the “Main group” (Fig.17). This group is habituated to human

presence and they often go to this beach, as since the beginning of these field studies,

researchers started to provide food (e.g., maize and sweet potato) to be able to study

them. In addition to the provisioning, researchers also weight the macaques. Maize is

placed on the scale in order for the researcher to weigh the macaques (Fig. 18). This

weighing task is very important because the body weight can give us valuable

information about their survival and reproduction. The mating season occurs in winter

and macaques are born during the next summer, with each female giving birth every 2/3

years. Because many babies were born last year, a low number of babies was expected

for this year. In fact, there were only two babies in the group (Fig. 19).

Jigokudani

09-10 November 2018

Before and even during the internship I had the opportunity to use my free time to visit

other places in Japan. On the second weekend of November (9-10 November) I went

with two colleagues (Jannie Wu and Pedro Warner) to visit Jigokudani Monkey Park.

14

Figure 20. Japanese macaque on the hot spring Figure 21. Japanese macaques on the hot spring

Figure 22. Japanese macaques on the hot spring

This park is located in Yamanouchi, Nagano Prefecture. Jigokudani Monkey park, also

known as Wild Snow Monkey Park, is famous for watching the bathing Snow monkeys

in a hot spring. In fact, Jigokudani means “Hell valley” due to the existence of these

sources of natural heat. Between December and March, the park becomes white, full of

snow.

We had to walk around half an hour to reach the place where monkeys can be

seen. There was no snow by this time of the year, but still, it was cold, and we could

walk through the forest with the beautiful autumn colours. Japanese macaques live in

troops that can reach over 100 individuals.

They live in constant motion in

their territory of several kilometres with

males moving to other troops when they

reach maturity. The staff provide some

food to the Japanese macaques living at

the park near the onsen as a strategy to

maintain them close to that area. Being

emerged in the warm water is also a good

way to fight the extremely cold

temperature that they face in winter (Fig.

20, 21 and 22).

15

Figure 23. SAGA 21 advirtising poster

Figure 24. Oral presentations at the Kumamoto Zoo

Kumamoto: SAGA (Support for African/Asian Great Apes) symposium and

Kumamoto Sanctuary 16-20 November 2018

SAGA (Support for African/Asian Great Apes)

consortium was establish in 1998 with the ultimate

goal of improving the welfare of the great apes. In

particular, SAGA aims to conserve the natural habitat

of wild great apes, enrich the lives of the great apes

living in captivity and to stop the use of great apes in

invasive research. As a result of this initiative, the last

goal was successfully achieved on 2006: in Japan,

there was no more invasive biomedical research on

chimpanzees. These chimpanzees were transferred

and are now housed at Kumamoto Sanctuary. Every

year, during the SAGA Symposium, researchers and

keepers have the opportunity to present their work and

discuss the ongoing studies on conservation and welfare in great apes. The 21st SAGA

Symposium took place on the 17th and 18th of November, 2018 (Fig. 23). The first day

was held in the Faculty of Kumamoto and comprised of two sessions of oral

presentations, one in the morning and another in the afternoon, followed by the poster

session, where I had an opportunity to present my previous work conducted at Fundació

Mona, as I had done at PWS.

The second day of the symposium was held at the Zoo. The oral presentations

just took place during the morning period (Fig.24). In the afternoon I had the

opportunity to visit the Cuddly Dominion

(formerly the Aso Kuma Bokujyo) (Fig.

25). Over 1000 animals from more than 90

different species live in this park. In

particular, the park hosts 170 bears of

different species, but unfortunately there is

still much work that can be done to

considerably improve their facilities and

welfare conditions (Fig.26).

16

Figure 27. Enrichment structure at the Kumamoto Sanctuary

Figure 26. One of the bear facilities at the Cuddly Dominion

Figure 25. Advirtisment at the entrance of the Cuddly Dominion

The Zoo currently hosts animal shows to attract people. One of the shows uses

non-human primates (an infant chimpanzee, a capuchin and a Japanese macaque)

among other animals for entertainment.

Several efforts have been done to negotiate the rescue of the primates involved.

In 2016 SAGA published a statement against the inappropriate artificial rearing of the

infant chimpanzee, Purin. This kind of rearing results in serious problems in their social

development, since the infant chimpanzee is treated in an anthropomorphic way and is

isolated from their conspecifics during this crucial developmental stage. Although they

are still using Purin, small achievements have been done regarding the weekly time they

participate in the show. This infant chimpanzee is a recent acquisition for the show. The

previous chimpanzee used for this purpose now resides in the zoo with one female in

the same facility. We were not on time to see the show, so we had no chance to see the

infant chimpanzee. Nevertheless, we saw the other two chimpanzees in the outdoor

enclosure.

On the 19th of November I had opportunity to

visit the Kumamoto Sanctuary. Before becoming a

sanctuary, these facilities were owned by the Sanwa

pharmaceutical company since 1978. They used

invasive techniques in chimpanzees for research on

infectious diseases such as hepatitis B, C and malaria.

In 2007 the pharmaceutical company stopped using the

chimpanzees for their invasive research, and in 2010

the premises became property of Kyoto University.

Although they had such a traumatic past, they now live

17

Figure 28. Female chimpanzee with a pout face at the Kumamoto Sanctuary Figure 29. Female bonobo at the Kumamoto

Sanctuary

in social groups which are in much better conditions (Fig. 27). The sanctuary has three

main buildings with corridors connecting them, which allow them to freely move

between buildings. In total there are 55 chimpanzees and 6 bonobos (Fig. 28 and 29).

In the evening we went to the Mizumi Port to see finless porpoises

(Neophocaena phocaenoides), The use of a drone allows the study of some behavioural

and motion patterns of these porpoises.

18

Figure 30. Tape with new label Figure 31. Network Attached Storage Device

Bossou video archive

The Bossou community of chimpanzees in the Republic of Guinea has been studied by

Kyoto University for decades (Matsuzawa, Humle, & Sugiyama, 2011; Sugiyama &

Koman, 1979). As a result of the work by Prof. Matsuzawa and colleagues, over 30-

years of high-quality video footage were systematically collected to study chimpanzee

stone tool use and other behaviour. This video archive is now stored in the KUPRI in

Inuyama, Aichi, and the Bossou Archive Project has been established with the core aim

of preserving and organising the video data, to enable future access and analysis by

researchers. Although the video tapes (Fig. 30) are being stored in climate-controlled

cabinets, in tape format they are inaccessible and at significant risk of damage with

time. Therefore, it is crucial to digitise them and to keep a backup of these files. The

video files of the Bossou Archive are being copied to a Network Attached Storage

Device (Fig. 31) which is synchronized with Amazon cloud for online access.

During my stay in Japan I continue the work of digitising and labelling the

remaining tapes, and processing and organising video files by splitting them into clips.

Below I outlined the main steps of the protocols that I followed, which were set out by

Dan Schofield, who has been developing the archive infrastructure as part of his PhD

project in collaboration with PRI.

Before digitising and storing them in the respective shelf (according to the year),

all the tapes were relabelled using a Unique identifier (UID) – a large randomised

sequence of numbers and letters, used as an identifier to ensure that content can be

accurately tracked and matched with tapes.

19

Figure 32. Working Excel Spreadsheet

Figure 33. Label template in the P-touch Editor

Labelling

The labelling process can be divided in three phases:

A. Create unique IDs using a UID generator website

(https://www.guidgenerator.com/)

B. Assign IDs to the physical tapes. For this purpose, copy the UIDs

generated in the website and paste them in the Working Excel

Spreadsheet (Fig. 32). Some of the information requested in other

columns can be completed by checking the tape settings in the menu of

the MDV player;

C. Print labels. The printing process can be described as follows:

1. Open the P-touch P700 software for the printer

2. Open the label template already designed for this purpose (Fig. 33). Each label

contains the QR code of the location of Primate Research Institute, the tape

UID; the Start Datetime, the Runtime and the location (Forest/ Bureau).

20

Figure 34. Brother label printer

Figure 35. Hardware for the digitising process.

3. Download the latest spreadsheet as a csv file on

the local computer.

4. Connect the Database File with your template:

File -> Database -> Connect;

Choose the text boxes for the fields on the label to

match up with the information on the spreadsheet.

5. Select all the labels you want to print and click on

the Print menu.

6. The labels come out from the “Brother label

printer” (Fig. 34)

Digitising

As a result of the work of several colleagues and students, a large number of tapes had

been already digitised by the time I arrived at PRI. During my 3 months internship, I

have digitised 225 tapes from several field seasons between 1998 and 2012.

The digitising process involved the following steps:

1. Play the blue cleaning tape around 10 seconds to clean the MDV player

2. Insert tape into player.

3. Open VIDI software (click stop and then rewind to be sure that the tape is at the

beginning).

4. Record the file: Select “Record as” in the File menu, paste the UID as file name

and choose the respective tape set folder in the ingest of the Bossou Archive

server; click “record” and then press play on the actual tape machine.

5. When the tape has no more

content, the MDV player screen

will be blue. To complete the

recording, click on the flashing red

“REC” button on VIDI software

and confirm that you want to stop

recording.

6. Quit VIDI software before moving

for the next tape (Fig. 35).

21

Splitting

In order to split the files from the digitised tapes into the continuous clips that they

contain, we need first to convert the files to an appropriate format (VOB->mp4). The

content of each digitised tape can be found in one folder of the Bossou archive named

with its UID. Occasionally, the content is divided in several large clips (varying from 2

to 5 clips). Nevertheless, it happens that these large clips can cut a continuous clip of

the tape. Therefore, it is also important to merge the large clips of each tape before

splitting into the small continuous clips.

During my internship I have converted, merged and split the files of 11 tapes

into 543 clips. The instructions for these 3 phases are described below:

(Preliminary step: Locate in the Master spreadsheet the tape with the files you

want to convert, merge and split. Go to the Bossou Archive and copy the folder

of that tape from the Bossou master and paste it in your ingest folder.)

A. Convert the files using HandBrake. Define the “Source” and the

“Destination” folder and “Save as…” mp4 file (look for HandBrake

Video Converter Tutorials on YouTube for further details).

B. Merge the files using ffmpeg and command prompt:

1. Copy the ffmpeg.exe file to the MP4 folder.

2. Open the command prompt window and change path to the folder where you

keep MP4 files (step-by-step tutorial in:

https://www.linglom.com/multimedia/combine-mp4-files-using-ffmpeg-

windows-without-re-encoding/

3. Create a text file which has a list of MP4 files that you want to combine by

typing this command and hit Enter: (for %i in (*.mp4) do @echo file '%i') >

mylist.txt

4. Type the following command to begin combining the files using ffmpeg and hit

Enter: ffmpeg -f concat -i mylist.txt -c copy output.mp4

C. Split the files into clips using QuickTime Player: Select “File”, “Trim”

and then adjust the starting and the ending point. “Save” and rename the

new file with the respective number of the clip.

22

Greeting Report

Introduction

During my internship at the Primate Research Institute I had opportunity to familiarise

myself with members of the Bossou chimpanzee community, and practice the

behavioural coding of chimpanzee communication that is the basis of my PhD project.

For this purpose, I analysed some videos from the Bossou Archive (2013), focusing on

greeting and leave-taking events.

Wild chimpanzees form large communities, but within their territories they form

smaller parties, with individuals coming and going between them (Goodall, 1986).

Within this ‘fission-fusion’ social organisation chimpanzees compete for social rank

within a hierarchy and form long-term alliances with both kin and non-kin group

members. Greeting behaviour plays a significant role in the formation and maintenance

of the greeter and greetee’s social rank and alliances, and also transmits valuable and

nuanced information about these to everyone present (Mcgrew & Baehren, 2016;

Whitham & Maestripieri, 2003).

In addition to tool using, the videos in the Bossou Archive contain abundant data

on the community’s communication (Fig.36). Chimpanzees employ large repertoires of

gestures, vocalizations, and facial expressions, to communicate a range of meanings and

information (Goodall, 1986; Hobaiter et al. 2017). During greeting events, the most

frequently observed and widely studied communicative behaviour is the pant-grunt

vocalization. This call is typically associated with showing subordination and is

unidirectional (it is always produced by a lower ranking individual towards a higher

ranking individual) (Laporte & Zuberbühler, 2010). However, greetings are not

necessarily unidirectional; chimpanzees may reciprocate greetings by employing other

signals and behaviour, varying their nature according to the social relationship and

identity of the greeters, such as age, sex, and social bonding (Luef & Pika, 2017).

Pant-grunts, like many types of signals, have typically been studied in isolation.

However, chimpanzee communication combines a wide range of signals, and

vocalizations are used in combination with gestures and facial expressions (Hobaiter,

Byrne, & Zuberbühler, 2017; Taglialatela et al., 2015; Waller, Liebal, Burrows, &

Slocombe, 2013). In captivity some gestures used in the context of greetings have

already been described in combination with pant grunts; for example: bobbing,

23

crouching, and presenting (de Waal, 2007). In the wild, additional gestures have been

reported including “nibble cheek”, “nibble ear”, and “embrace”, among others (see Luef

& Pika, 2017). In addition to greetings, humans, who also live in a fission-fusion social

structure, perform rituals before parting. However, such behaviour seems to be very

uncommon in chimpanzees and other non-human primates (Mcgrew & Baehren, 2016).

To understand the behavioural asymmetry related to the greeting and parting events,

more data on leave-taking and the opportunities for parting rituals are needed. In this

report I included data on the contexts of greeting and leave-taking, as well as describing

any communication observed within both types of events.

Figure 36. Video from Bossou Archive. From left to right: Yo, JEJE, Fanle, FANWA, FLANLE and Fana.

Methods

Defining greeting and leave-taking

Greeting events may occur when an individual encounters other individuals after a

period of separation. The definition of a ‘Potential greeting event’ was adapted from

Laporte and Zuberbühler (2010) as: any individual entering a 15 meters radius

surrounding the focal animal. Within Potential greeting events, we distinguish between

‘First Arrivals’ and ‘Encounters’. First arrivals corresponded to the first contact with the

group during the observational sessions where the clips were extracted. Greeting events

that occurred after this first arrival were coded as Encounters. Potential greetings were

considered as separated events when separated by at least 5 minutes.

24

A ‘Potential leave-taking event’ was defined as the period immediately before

one or more individuals leave the party. Potential leave-taking events were categorized

into ‘Absences’ or ‘Final departures’. In order to be categorized as an Absence, the

chimpanzee had to later re-join the party during the observational session, but spaced at

least with a 5 minutes interval to be considered as an independent event. When the

chimpanzee did not come back during the observation session, the event was classified

as Final departure.

Greeting and leave-taking potential events could include several greeting and

leave-taking ‘Opportunities’ respectively. An Opportunity was marked for each dyad

that satisfied the definitions of greeting and leave-taking previous described. For

example: if Yo arrives to a party composed of JJ and FF, this Potential greeting event

has two Greeting opportunities: Yo and JJ; Yo and FF).

The ‘Greeter’ and ‘Leaver’ were defined as the first chimpanzee signaling

during greetings and leave-takings, respectively. The ‘Greetee’ and ‘Leavee’ were the

recipients of those initial signals, even where they then subsequently responded with

signals of their own.

Subjects and Field Site

Data were collected from a natural outdoor ‘laboratory’ (Salon) that had been created in

the Bossou forest. The area is flat and clear, so filming conditions are ideal, allowing

recording of all individuals within and arriving at the party. In December 2013 there

were 9 chimpanzees at Bossou: five adult females (Jire, Fana, Fanle, Yo and Velu), two

adult males (JEJE and FOAF), one juvenile male (FLANLE), one infantile male

(FANWA). Jire was the mother of the current alpha-male, JEJE. Fana was the mother of

FOAF and Fanle. Fanle was the mother of the two young males: FLANLE and

FANWA. At this time, Yo and Velu had no relatives living in the group (Fig. 37).

25

Figure 37. Bossou chimpanzees 2013

Structuring the behavioural repertoire for greeting events

During this training period we explored two different modalities of signals: gestures and

vocalizations.

The gestures were adapted from the repertoire described in Hobaiter and Byrne

(2011) and included: Arm raise, Arm shake, Arm wave, Beckon, Big Loud Scratch,

Bipedal rocking, Bipedal stance, Bite, Bow, Clap, Cover, Dangle, Embrace, Feet shake,

Fling, Grab, Hand on, Head butt, Head shake, Head stand, Hit object/ground, Hit

26

object/ground 2-handed, Hitting other, Jump, Knock object, Leaf clipping, Locomote,

Look, Object in mouth, Object move, Object on head, Object shake, Poke, Pounce,

Present, Push, Push (directed), Reach, Rocking, Roll over, Rump rub, Shake hands,

Spin, Stomp, Stomp other, Stroke, Swing, Tandem walk, Tap object, Tap other, Throw

object, Thrust, Touch, Water splash, Unknown.

The vocalizations were adapted from the repertoire described in Luef & Pika

(2017). The following categories were included: Pant bark, Pant grunt, Pant-hoot, Pant

other (includes Pant grunt bark, Pant grunt scream, Pant grunt other), None, Unknown.

Response behaviour for each greeting were coded as: Gives Affiliation, Receives

Affiliation, Pays Attention, Chases, Climbs on, Permits Climb on, Follows, Grooming

given, Permits grooming by signaller, Looks but no response, Moves away, Moves

closer, Nurses, Picks, up, Play, Gives object/food, Gives sexual attention, Receives

sexual attention, Gives support, Receives support, Stops behaviour, Travels, Other,

Unknown.

Data coding and analysis

Approximately 27 hours of videos were reviewed, within

which 98 potential greeting and leave-taking events were

isolated for detailed analysis. The software used for data

coding was Cybertracker. Cybertracker is a very efficient

software used for data collection in the field. This

software can be accessed through an application on a

tablet or smartphone. The simple and didactic menus

make this software a good tool to rapidly code greeting

data from the selected video clips (Fig. 38).

There were 7 main pages in the coding directory:

Behaviour; Party composition; Greeter, Greetee; Signal

type; Response (screen similar to the Signal type, plus a

screen for Response behaviour); Notes. The Signal type

had several sub-pages including: Gesture and

Vocalization. The categories included in each signal type

subpage are described in the previous section.

Descriptive analyses and graphics were processed in Microsoft Excel.

Figure 38. Example of a Cybertracker screen for the Party composition

27

Results

I identified 33 Potential greeting events and 65 Potential leave-taking events. From the

Potential greeting events, 28 corresponded to a First arrival. From the Potential leave-

taking events, 57 corresponded to a Final departure.

Greeting events

Within the 33 Potential greeting events, greetings occurred between two individuals in

23 (70%) of them. Within these 23 events, I identified 81 Greeting opportunities that

culminated in 31 greetings. Most of these greetings (26 out of 31) used only one

modality (8 vocal and 18 gestures). The dominant alpha male at the time, JEJE, was

both the most frequent Greeter (n=7; all gestural) and Greetee (n = 11; 4 gestural and 7

vocal) (Fig. 39).

Figure 39. Number of greetings as Greeter and Greetee.

Reciprocal greetings

Approximately 70% (n=28) of the greetings elicited responses: behavioural (n=14);

gestural (n=6) and vocal (n=8). Among the behavioural responses, the most common

behaviour was Look but no response (n=5), followed by Move away (n=4), Permit

grooming (n=2), and Grooming given (n=2).

Leave-taking events

Within the 65 potential leave-taking events, I identified 134 leave-taking opportunities,

in which interactions occurred in only 5 occasions. The number of opportunities that

0

2

4

6

8

10

12

14

16

18

20

FE FF Fl Fn FW JJ Jr Vl Yo

Nu

mb

er o

f gr

eeti

ngs

Bossou chimpanzees

Greetee

Greeter

28

culminated in interactions was ten times higher in potential greeting events (40%, n=32)

than in potential leave-taking events (4%, n=5) (Fig. 40).

Figure 40. Percentage of greetings and leave-takings

Table 1 shows the signal types that make 85% of the total data collected for greetings.

Among the 85% most common signal types, Pant-grunt occurred the most often. When

Pant-grunts occurred in combination with another vocalization, these were included in

the Pant-other category (the third most frequent signal type). During greetings, Touch,

Present and Head shake were the 3 most popular gestures

Table 1.The most frequent signals emitted during greetings. Vocalizations are marked with [V] and Gestures with [G] after each signal type.

Signal Occurrences (%)

Pant-grunt [V] 19

Touch [G] 17

Pant-other [V] 12

Present [G] 9

Head shake [G] 7

Bipedal stance [G] 5

Object shake [G] 5

Arm wave [G] 4

Embrace [G] 4

Locomote [G] 4

Pant-hoot [V] 4

Discussion

Greetings occur regularly in chimpanzees, and seem to reflect and important part of

their social relationships. Most greetings were reciprocal and involved both vocal and

gestural signals. However, either the Greeter or the Greetee preferably used only one

0%

20%

40%

60%

80%

100%

Greeting Leave-taking

29

signal type within a particular greeting, and most of the elicited responses were

behavioural. Adult males were more often involved in greetings. Pant-grunts were the

most frequent signal type. The gestures Touch and Present, plus the vocalization Pant-

grunt in combination with other vocalizations were also often observed in these events.

Despite the fact that we identified more leave-taking opportunities, as opposed to

greeting opportunities, very few interactions occurred that could be described as leave-

taking events.

Greeting events are widely reported in the literature, but leave-taking events

have received less attention, and my preliminary results support the findings that leave-

taking events are very scarce in chimpanzee behaviour. Even, during the Leave-taking

opportunities, it was difficult to be confident that the interactions that occurred were for

the purpose of leave-taking. Other social interactions may occur immediately before the

potential leave-taking event, other signals may have been used for other purposes, such

as a request to travel together that was then ignored or refused. Leave-taking could be

described as a declarative communication. As a result there is no need for the recipient

to change their behaviour in any clear way, making identifying relevant behaviour very

challenging.

JEJE, the alpha male, both received the most greetings, but was also the most

common Greeter among the group members. Because greeting events can provide

valuable information about social rank (Mcgrew & Baehren, 2016) and are usually

unidirectional from a lower-ranking element towards a higher-ranking element (Laporte

& Zuberbühler, 2010), JEJE’s regular presence in these interactions was expected.

However there appear to be interesting differences depending on his role in the

interaction: as the Greetee he received greetings that were typically pant-grunt

vocalizations, and as the Greeter he employed gestures to greet other group members.

FOAF, the only other adult male at the time and the ex-alpha male, was also

often greeted by the adult females of the group. Although vocal greetings start to occur

early in the development (Laporte & Zuberbühler, 2011), it was not possible to clearly

establish whether or not FANWA (aged 2 years) used vocalizations in this pilot data.

As he was typically in physical contact with his mother while arriving or leaving, it was

challenging to discriminate greetings directed to him, from those directed to her.

Similarly any vocal greetings by him were difficult to discriminate from those given by

his mother Fanle.

30

My data support the findings from other groups that the Pant-grunt call is

strongly associated with greeting events (Laporte & Zuberbühler, 2010). However, it

would be interesting to categorize the pant-grunts that occurred in combination with

other vocalizations, such as Bark and Screams, and that were included in the Pant-other

categories. I am in the process of undertaking more training in order to be able to

properly distinguish these more subtle vocal call categories, as well as more reliable

coding of gestures. Facial expressions are also important, and have been typically

ignored in studies of wild ape communication due to the challenges of coding them

from field data (Slocombe, Waller, & Liebal, 2011). In the future, it would be also

interesting to include and categorize the different types of facial expressions.

The data briefly discussed and analysed in this report are preliminary and

correspond to my first experience of these research tools, methods, and behaviour. As a

result my interpretation of these findings is cautious; however, it provides an important

starting point for my future studies.

31

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