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
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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