Pan Africa NewsThe Newsletter of the Committee for the Careand Conservation of Chimpanzees, and the Mahale
Wildlife Conservation Society
ISSN 1884-751X (print), 1884-7528 (online) mahale.main.jp/PAN/

DECEMBER 2016
P. A. N. EDITORIAL STAFF
Chief Editor:
Kazuhiko Hosaka, Kamakura Womenʼs University, Japan
Deputy Chief Editor:
Michio Nakamura, Kyoto University, Japan
Associate Editors:
Christophe Boesch, Max-Planck Institute, Germany
Jane Goodall, Jane Goodall Institute, USA
Tetsuro Matsuzawa, Kyoto University, Japan
William C. McGrew, University of Cambridge, UKJohn C. Mitani, University of Michigan, USA
Vernon Reynolds, Budongo Forest Project, UK
Yukimaru Sugiyama, Kyoto University, Japan
Richard W. Wrangham, Harvard University, USA
Takeshi Furuichi, Kyoto University, Japan
Editorial Secretaries:
Noriko Itoh, Kyoto University, Japan
Koichiro Zamma, Kyoto University, Japan
Agumi Inaba, Mahale Mts. Chimpanzee Research Project
Eiji Inoue, Toho University, Japan
Instructions for Authors:
Pan Africa News publishes articles, notes, reviews,
forums, news, essays, book reviews, letters to editor, andclassified ads (restricted to non-profit organizations) on any
aspect of conservation and research regarding chimpanzees(Pan troglodytes) and bilias (Pan paniscus). Contributors arerequested to write in English and the papers except forums,
reviews and essays should usually be 1,500 words or less.
Articles, notes and reviews will be peer-reviewed by at least one
appropriate expert on request of the PAN editorial staff.
PAN is published twice a year in June and December.
Deadline for manuscripts is two months before publication (i.e.,
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• Manuscripts: Format as DOC or RTF files• Photos and figures: Format as JPEG or GIF files. Do NOT
paste on Word files or create as PDF files. Figures could besent as excel files also.
• Audiovisual data: Authors could include audiovisual data toenhance their papers, although they will be included in the
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• Send these separately by e-mail attachments.
See also http://mahale.main.jp/PAN/instruction.html
Deadline of the next issue is April 2017!

VOL. 23, NO. 2

Contents<NOTE>An Annular Solar Eclipse at Mahale: Did
Chimpanzees Exhibit Any Response?
Michio Nakamura & Hitonaru Nishie		

9<NOTE>Do Not Disturb! A Factor in Bed Site Relocation
among Mahale Chimpanzees
Koichiro Zamma				13<NEWS>
What is the Human Evolution Bed?
The Human Evolution Bed Project Team

15

<From the Editor>			

16<NOTE>An Annular Solar Eclipse at
Mahale: Did Chimpanzees
Exhibit Any Response?
Michio Nakamura1 & Hitonaru
Nishie1,2
1 Graduate School of Science, Kyoto University, Japan
2 JSPS Research Fellow(E-mail: nakamura@jinrui.zool.kyoto-u.ac.jp)

Introduction

Contemporary humans often enjoy observing solar
eclipses as astronomical shows. In the mystic atmosphere
under an eclipsing sun, one might ask, “How ancestral humans faced such events without understanding their causal mechanism? With fear or with fascination?” Similarly,
it may be interesting to know how animals respond tosuch solar events.
The behavior of animals in captivity has been observed during solar eclipses. For example, antelope
ground squirrels (Ammospermophilus leucurus) exhibit

9Pan Africa News, 23(2), December 201610
increased locomotor activity during a partial solar eclipse(Kavanau & Rischer 1973). In contrast, hamadryas baboons (Papio hamadryas) become less active during a solar eclipse (Gil-Burmann & Beltrami 2003). Interestingly,
captive chimpanzees (Pan troglodytes) have been observed to climb up high structures, orient their bodies
toward the sun, and even gesture toward the sun during
an annular solar eclipse (Branch & Gust 1986). During
an annular eclipse, simultaneous observations of captive
chimpanzees were made at eight Japanese institutions(zoos and research institutes). Notable behaviors, such as
shouting at the sun, looking up at the sky, or showing general excitement, were reported at four of these institutions(Kato et al. 2013). However, the authors caution that thesebehaviors may be caused by increased human presence(and excitement) rather than the eclipse itself.
There have been fewer reports on the responses ofanimals in the wild to solar eclipses. In one study, theEuropean ground squirrel (Spermophilus citellus) did
not show any marked behavioral change during a partial
eclipse (Spoelstra et al. 2000). An extensive survey on the
behaviors of various animals at the Mana Pools National
Park in Zimbabwe during a total eclipse revealed that hippopotamuses and many birds behaved as though it wasdusk, impalas exhibited increased vigilance, and baboons
exhibited feeding cessation (Murdin 2001). However,there appears to be no reports on the responses of wild
chimpanzees to solar eclipses.
On September 1, 2016, we unexpectedly observed
an annular eclipse at the Kasoje area in the Mahale
Mountains National Park, Tanzania, where research on
habituated chimpanzees has been conducted for more than
50 years (Nakamura et al. 2015). Although there are norecords of solar eclipses at Mahale, online eclipse predictions by Fred Espenak (EclipseWise.com online) indicatedthat till date, several solar eclipses have occurred in the
Kasoje area since the commencement of the chimpanzee

study (Table 1). However, this was the first annular eclipse
in the Mahale research history (and the next will be in2064). Therefore, here we report the chimpanzee behavior
during this rare annular solar eclipse.

Particulars of the annular solar
eclipseOn the day of the eclipse, no author was aware thatthe event was going to occur. HN was at the Kansyana
Research Camp, Kasoje area, at Mahale and was notifiedof the impending solar event by a research assistant who
heard the news on the radio. According to EclipseWise.
com (online), the annular eclipse was observed in a wide
area from the Indian Ocean to Madagascar and Central
Africa to the Atlantic Ocean. At Kansyana (6°7′1″S,29°44′23″E), the event lasted from 09:49 h to 13:29 h,with the annular state occurring for approximately 2.5
min between 11:32 and 11:35 h at a maximum magnitudeof 97.3% (Figure 1).
There was no rain during 11 days (August 27 toSeptember 6) including the day of the eclipse owing toSeptember being at the end of the dry season at Mahale.
The temperature started falling at 11:00 h, and at 11:50
h, as the eclipse was receding, the temperature was approximately 5°C below the average temperature on thesurrounding 10 days (Figure 2); at 12:50 h, toward the endof the eclipse, this difference reduced below 2°C. We did
not monitor luminous intensity, but when the eclipse wasat maximum magnitude, HN felt that it was as dark as at
dusk.

Chimpanzee behavior during thesolar eclipse
On the day of the eclipse, MN met a party of chimpanzees including the alpha male at 07:55 h and started
following an adult female, Linda (estimated to be 36 years

Table 1. Solar eclipses observed at Kansyana Camp (6°7′1″S, 29°44′23″E) since thecommencement of chimpanzee research in 1965 (based on eclipse predictions by Fred
Espenak on EclipseWise.com online).

Date
Jun 30, 1973
Apr 18, 1977
Feb 16, 1980
Dec 4, 1983
Mar 29, 1987
Nov 3, 1994
Jun 21, 2001
Dec 4, 2002
Oct 3, 2005
Mar 29, 2006
Jan 15, 2010
Nov 3, 2013
Sep 1, 2016

SeasonKind of eclipse

Dry
Wet
Wet
Wet
Wet
Wet
Dry
Wet
Dry to Wet
Wet
Wet
Wet
Dry

PartialPartialPartial**PartialPartialPartialPartialPartialPartialPartialPartialPartialAnnular

Eclipse magnitude
(%)
65.9
84.9
99.8
75.6
58.8
8.8
75.3
62.4
63.9
8.6
74.1
74.7
97.3

* Local standard time at maximum magnitude (UT + 3).
** Bilenge, which later became the park headquarters, experienced the total eclipse.

Time*
15:58 h13:45 h10:59 h17:03 h16:59 h18:26 h16:15 h08:56 h14:19 h12:33 h08:21 h17:22 h11:34 hPan Africa News, 23(2), December 2016

11

Figure 1. The annular eclipse observed at Kansyana Camp on September 1, 2016.

old), at 08:28 h. At around 09:30 h, most party members
began moving westward, whereas Linda and her 4-yearold daughter, Lenge, did not follow the others and started
moving eastward. At around 11:00 h, MN noticed that thesky began to darken. Being unaware of the occurrenceof the eclipse and with limited visibility of the sky fromthe forest, he thought that the sun was being obscured bythick clouds, as it often happens during the wet season
at Mahale, and wrote in the field notes: “it is becoming

cloudy”; at 11:30 h, he wrote, “it is very gloomy”; and at
11:59 h, he wrote, “sunlight is back.” MN continued to follow Linda until 17:00 h. On return to the research camp,
he was informed by HN that the eclipse had occurred.
Ex post facto investigation was conducted on the
behaviors of the focal female, Linda, and her daughter,
Lenge, during the eclipse. At 11:00 h, when MN first noticed that the sky had begun to dim, Linda was feeding on
Saba comorensis fruits and Lenge was resting in a nearby

Figure 2. Comparison of temperatures between the day of the eclipse (dashed line) and theaverage of the surrounding 10-day period (August 27–31 and September 2–6) (solid line). Error
bars show standard deviations. A double vertical line shows the time of the annular eclipse.

Pan Africa News, 23(2), December 2016

12

Figure 3. Linda (above) and Lenge (below) fishing for ants at 12:48 h on the day of the eclipse.

bed. Soon, they began moving eastward. At 11:13 h, Linda
made some tools, and both chimpanzees began fishing forarboreal ants. At 11:30 h, when the sky was the darkest,
they were still fishing for ants. Linda continued fishingfor ants (Figure 3) until 14:56 h, whereas Lenge fished intermittently, begged Linda for tools or a place to fish ants,
suckled on Linda’s nipple, or foraged nearby for fruits.
There was no indication that Linda or Lenge particularlychanged their behavior during the eclipse. Although thetwo were by themselves when the eclipse occurred, MN
was aware that other chimpanzees were nearby, so callsby other chimpanzees would have been heard. As no calls
were heard during the time of the eclipse, it was assumed
that the other chimpanzees did not vocally respond to theeclipse.

Discussion

Unlike that in previous studies on captive chimpanzees (e.g., Branch & Gust 1986), Linda and her daughter,
Lenge, did not exhibit any specific behavioral change during the eclipse, and continued fishing for ants in the tree.
This lack of response to the eclipse may have been due tothem not being able to see the eclipsing sun as the location
where they were fishing for ants was covered by a thickcanopy of leaves. This may be consistent with the resultsin the report on captive chimpanzees, in which cloud
cover prevented the observation of the eclipse because ofwhich chimpanzees exhibited no any specific response(Kato et al. 2013). Apparent excitement or curiosity observed in some captive chimpanzees may be more likely
when there is no overhead coverage, as in zoos, and whenthe eclipsing sun is directly visible.
Owing to overhead tree coverage, wild chimpanzees
may not be able to directly observe eclipse events. Thus
the question is whether or not wild chimpanzees can detect something unusual in the unexpected onset of darkness alone. As we experienced an annular rather than atotal solar eclipse in the present study, although it became

quite dark, it still was sufficiently bright for chimpanzees
to continue ant-fishing and for MN to write field notes.
During partial eclipses with smaller eclipse magnitudes,
it may be increasingly difficult for chimpanzees to detecta difference between darkness caused by cloudiness andthat by eclipse. Onset of darkness to some extent may notaffect them much as they are accustomed to such darkening events by sudden occurrences of heavy clouds in thewet season. Furthermore, it is likely that solar eclipses
during the wet season go unnoticed because the sky isoften covered with thick clouds. This may also explain
the lack of previous reports on eclipses at Mahale, as mosteclipses occurred in the wet season (Table 1). Althoughwild chimpanzees are known to perform “rain dances”
when it starts raining heavily (Goodall 1986), no obvious
behavioral changes have been noted when the sun is simply obscured by thick clouds. Thus, the lack of obvious
behavioral changes by Linda and Lenge was unsurprising.
The question still remains on how chimpanzees respond during a total solar eclipse when the forest is suddenly covered in complete darkness during the day. There
will be long wait before a total eclipse occurs at Mahale
or at other chimpanzee research sites in the wild.

Acknowledgements

We thank COSTECH, TAWIRI, and TANAPA for permission to conduct research at Mahale. HN’s field study was financially supported by Grant-in-Aid for JSPS Fellows (#14J00963).

References

Branch JE, Gust DA 1986. Effect of solar eclipse on the
behavior of a captive group of chimpanzees (Pan troglodytes). Am J Primatol 11:367−373.
https://doi.org/10.1002/ajp.1350110407

EclipseWise.com [online] Available at: http://eclipsewise.com/.
[Accessed November 29, 2016].
Gil-Burmann C, Beltrami M 2003. Effect of solar eclipse
on the behavior of a captive group of hamadryas baboons(Papio hamadryas). Zoo Biol 22:299−303.
https://doi.org/10.1002/zoo.10077

Goodall J 1986. The Chimpanzees of Gombe: Patterns ofPan Africa News, 23(2), December 2016
Behavior. Belknap Press, Cambridge, Mass.
Kato Y, Yamada N, Konishi K et al. 2013. [Behaviors of captive chimpanzees at annular solar eclipse: Comparisons ofeight Japanese zoos and institutes by application of a mailing list.] Internet J Environ Enrichment 7:e142, in Japanese.
Kavanau JL, Rischer CE 1973. Ground squirrel behaviour
during a partial solar eclipse. Bolletino Zool 40:217–221.
https://doi.org/10.1080/11250007309430071

Murdin P 2001. Effects of the 2001 total solar eclipse on
African wildlife. Astron Geophys 42:40–42.
https://doi.org/10.1046/j.1468-4004.2001.0420044.4.x

Nakamura M, Hosaka K, Itoh N, Zamma K (eds) 2015.
Mahale Chimpanzees: 50 Years of Research. Cambridge
University Press, Cambridge, UK.
https://doi.org/10.1017/CBO9781107280533

Spoelstra K, Strijkstra AM, Daan S 2000. Ground squirrel activity during the solar eclipse of August 11, 1999. Z
Saugetierkunde 65:307–308.

13
by the activity of these animals.
The eastern red colobus (Procolobus rufomitratus)
is the predominant prey species of Mahale chimpanzees(Hosaka 2015), but colobus monkeys sometimes counterattack chimpanzees that are attempting to hunt them
(Hosaka 2002; Boesch et al. 2002); chimpanzees also occasionally detour to avoid a colobus (Boesch et al. 2002).
Furthermore, it was reported in the early 2000s that colobus males in Mahale even began to attack chimpanzees
that were not attempting to hunt them (Hosaka & Ihobe2015).
In this paper, I report a case in which chimpanzees
abandoned an attempt to make beds in a tree because of
the threat posed by two red colobus monkeys.

METHODS<NOTE>Do Not Disturb! A Factor in Bed
Site Relocation among Mahale
Chimpanzees
Koichiro Zamma
Graduate School of Asian and African Area Studies, Kyoto
University, Japan(E-mail: zamma@jambo.africa.kyoto-u.ac.jp)

I conducted this research in Mahale Mountains
National Park, Tanzania, in October and November 2016.
In Mahale, 70 mammal species (11 orders) have beenrecorded (Ihobe 2015). I observed the M-group chimpanzees in the Park. During the study period, the mean timeat which chimpanzees started making beds was 18:34 h(range: 18:19–19:11 h; n = 15).

OBSERVATIONOn October 19, 2016, I observed a party consistingof two adult females (Zola and Puffy), their offspring(Zolfa, Zamma, and PF14), and an adult male (Primus).

INTRODUCTION

Chimpanzees (Pan troglodytes) sleep in self-madebeds in trees; the sleeping sites are associated with daily
activity and selected to ensure safe, comfortable sleeping. In the daytime, chimpanzees forage within theirhome range. Therefore, sleeping site selection can be affected by the distribution of food resources. For example,
chimpanzees in Kalinzu Forest, Uganda, prefer to makebeds in fruit-rich areas (Furuichi & Hashimoto 2004),
while chimpanzees in the savanna woodland of Ugalla,
Tanzania, frequently select slopes close to water as bed
sites (Ogawa et al. 2014). A slope is also a safe place thatallows avoidance of predators, such as lions (Pantheraleo) and leopards (P. pardus), because the slope underbrush is insufficiently dense to conceal these predators(Hernandez-Aguilar 2009; Ogawa et al. 2014).
The beds are made of branches, twigs and leaves,such that the comfort of beds may differ among bed tree
species. In Semliki, Uganda, chimpanzees prefer a tree
species with stiff branches because this affords firm, stable beds (Samson & Hunt 2014). Chimpanzees in Mahale,
Tanzania, prefer tree species with greater total leaf areaon the branch, because these yield leafier beds (Zamma &Ihobe 2015).
However, chimpanzees do not always make their bedsin the most suitable tree, or in the optimum location. For
example, fruiting trees may be good locations for beds tomonopolize the available fruit (Fruth & Hohmann 1996;
Basabose & Yamagiwa 2002), but sleep in fruiting trees
might be disturbed by nocturnal frugivores (Fruth &Hohmann 1996). There are many animals in forests, andbed tree selection by chimpanzees is presumably limited

Figure 1. Chimpanzees and a red colobus monkey. The
chimpanzees attempted to hunt the red colobus monkey,
but they hesitated to approach it. The photo was taken
on October 23, 2006.

14
These chimpanzees were eating fruit in a tree at 18:09 h.
At 18:34 h, Primus left the tree, and the others left it a few
minutes later. I followed the splinter party that comprised
the two adult females and their offspring.
At 18:35 h, Puffy ate the leaves of a herbaceousvine (this was the last observation made of the chimpanzees feeding that day). At 18:40 h, they climbed a
Lecaniodiscus fraxinifolius tree and sat on branches. I
observed old chimpanzee beds in the tree and also found
two red colobus monkeys in a neighboring tree (I could
not identify the tree species at the time, but it was probably an Albizia glaberrima tree). One of the colobus monkeys screamed and the other shook the branches. Zola andPuffy stayed in the L. fraxinifolius tree for a few seconds,
but then descended. At 18:41 h, the chimpanzees climbed
a second tree about 20 m from the first. However, at 18:43
h, the red colobus monkeys approached the second tree
along the branches and threatened the chimpanzees again.
Zola, Puffy, and their offspring left the tree and quickly
walked away on the ground.
After 8 minutes, at 18:51 h, the chimpanzees climbed
a third tree. I did not observe any red colobus monkeys
near this third tree. At 18:52 h, Zola started to make a bed,
which she finished at 18:55 h. Puffy finished making her
bed at 18:56 h.

DISCUSSION

The chimpanzees, Zola and Puffy, likely wanted tomake beds in the first tree. This tree was considered to
be a suitable bed tree because it contained old chimpanzee beds, and they climbed the first tree at close to themean starting time of bed making during the study period(18:34 h).
However, when the chimpanzees climbed the tree, redcolobus monkey in a neighboring tree, which was believed
to be the colobus sleeping site on that day, threatened thechimpanzees. Chimpanzees are known to prey on red
colobus monkey (Hosaka 2015), so the colobus monkeys
might attempt to chase off potential predators so that they
do not disturb their sleep.
The chimpanzees descended the first tree within 1
minute of climbing it, which implies that they escapedfrom the red colobus monkeys at that time. In comparison with other study sites, such as Taï, Côte d’Ivoire, redcolobus monkeys in Mahale are often aggressive towards
chimpanzees (Figure 1; Boesch et al. 2002; Ihobe 2002;
Hosaka & Ihobe 2015). In some cases, red colobus monkeys bite chimpanzees (Hosaka 2002). Therefore, whenchimpanzees encounter a red colobus troop while moving in the forest, they sometimes either ignore it without
attempting a hunt, or even change direction to avoid it(Boesch et al. 2002).
In Mahale, chimpanzees do not show a great response to the sound of footsteps at night (Zamma 2014).
Nocturnal animals walking on the ground, such as bushpigs (Potamochoerus larvatus), cannot attack chimpanzees in trees, so chimpanzees may pay little attention tosuch animals. On the other hand, arboreal animals candisturb chimpanzees sleeping in beds in trees at night. To
ensure a comfortable sleep, chimpanzees may make beds
away from aggressive red colobus monkeys at dusk.

Pan Africa News, 23(2), December 2016
ACKNOWLEDGEMENTS

I would like to thank TAWIRI, COSTECH, and TANAPA
for their research permission, and M-GWRC and MMNP for logistic support. I also thank K. Hosaka for helpful comment, andT. Nemoto, A. Kanayama, G. Idani, and H. Nishie, for their kind
support. This work was supported by JSPS KAKENHI Grant
Numbers JP16K01980 (to Masayoshi Shigeta), JP16KT0006 (toMiho Nakamura), and JP 15H04429 (to Michio Nakamura).

REFERENCES

Basabose AK, Yamagiwa J 2002. Factors affecting nesting site choice in chimpanzees at Tshibati, Kahuzi-Biega
National Park: inf luence of sympatric gorillas. Int J
Primatol 23:263–282.
https://doi.org/10.1023/A:1013879427335

Boesch C, Uehara S, Ihobe H 2002. Variations in chimpanzee-red colobus interactions. In: Behavioural Diversity
in Chimpanzees and Bonobos. Boesch C, Hohmann
G, Marchant LF (eds), Cambridge University Press,
Cambridge, pp. 221–230.
https://doi.org/10.1017/CBO9780511606397.022

Fruth B, Hohmann G 1996. Nest building behavior in
the great apes: The great leap forward? In: Great Ape
Societies. McGrew WC, Marchant LF, Nishida T (eds),
Cambridge University Press, Cambridge, pp. 225–240.
https://doi.org/10.1017/CBO9780511752414.019

Furuichi T, Hashimoto C 2004. Botanical and topographicalfactors influencing nesting-site selection by chimpanzees
in Kalinzu Forest, Uganda. Int J Primatol 25:755–765.
https://doi.org/10.1023/B:IJOP.0000029121.25284.7f

Hernandez-Aguilar RA 2009. Chimpanzee nest distribution
and site reuse in a dry habitat: implications for early hominin ranging. J Hum Evol 57:350–364.
https://doi.org/10.1016/j.jhevol.2009.03.007

Hosaka K 2002. Hunting and meat-eating behavior. In: The
Mahale Chimpanzees: 37 Years of <Panthropology>.
Nishida T, Uehara S, Kawanaka K (eds), Kyoto University
Press, Kyoto, pp. 219–244, in Japanese.
Hosaka K 2015. Hunting and food sharing. In: Mahale
Chimpanzees: 50 Years of Research. Nakamura M, Hosaka
K, Itoh N, Zamma K (eds), Cambridge University Press,
Cambridge, pp. 195–212.
Hosaka K, Ihobe H 2015. Interspecific relationships. In:
Mahale Chimpanzees: 50 Years of Research. Nakamura M,
Hosaka K, Itoh N, Zamma K (eds), Cambridge University
Press, Cambridge, pp. 213–224.
Ihobe H 2002. Anti-chimpanzee hunting strategies of red colobus. In: The Chimpanzees at Mahale: 37 Years Study of<Panthropology>. Nishida T, Uehara S, Kawanaka K (eds),
Kyoto University Press, Kyoto, pp. 245–260, in Japanese.
Ihobe H 2015. Mammalian fauna. In: Mahale Chimpanzees:
50 Years of Research. Nakamura M, Hosaka K, Itoh N,
Zamma K (eds). Cambridge University Press, Cambridge,
pp. 195–212.
Ogawa H, Yoshikawa M, Idani G 2014. Sleeping site selection
by savanna chimpanzees in Ugalla, Tanzania. Primates
55:269–282.
https://doi.org/10.1007/s10329-013-0400-4

Samson DR, Hunt KD 2014. Chimpanzees preferentiallyselect sleeping platform construction tree species with biomechanical properties that yield stable, firm, but compliant
nests. PloS One 9:e95361.
https://doi.org/10.1371/journal.pone.0095361

Zamma K 2014. What makes wild chimpanzees wake up atnight? Primates 55:51–57.
https://doi.org/10.1007/s10329-013-0367-1

Zamma K, Ihobe H 2015. Bed making and nocturnal behavior. In: Mahale Chimpanzees: 50 Years of Research.
Nakamura M, Hosaka K, Itoh N, Zamma K (eds).
Cambridge University Press, Cambridge, pp. 583–598.

Pan Africa News, 23(2), December 201615

<NEWS>

Editor's Note
Primatologists studying wild chimpanzees assume the responsibility to meet the academic curiosityof the general public interested in their scientific findings and conservation activities. However, there
have been very few cases of “biomimicry” in which an investigation of chimpanzee artifacts inspires
manufacturers to create a new product that can make our living more comfortable. Here, we introduce
such a rare project in which a researcher, a designer and a bedding product expert are collaborating to
produce “the Human Evolution Bed” that has received media coverage both in Japan and abroad (e.g.,
McCurry 2016).
McCurry J 2016. Chimpanzees hold secret to ultimate comfy bed, says expert. The Guardian [online] June
21. Available at: https://www.theguardian.com/world/2016/jun/21/chimpanzees-bed-sleep-humankind-evolution-bed. [Accessed
December 24, 2016]

What is the Human Evolution
Bed?
The Human Evolution Bed ProjectTeam(E-mail: info@iozon.co.jp)

The Human Evolution Bed came from the desire tohave the comfort of a chimpanzee bed in our lives. In an
era when many are anxious about sleep, we wished tobring them a new kind of sleep, one that they have neverbefore experienced.
A wild chimpanzee makes its own bed each day, 365

beds a year, and over 10,000 in a lifetime, in a tree, byfolding branches to form a shallow oval bowl. It looks
different from our beds, which are flat and rectangular.
One day in an African forest, Koichiro Zamma (Graduate
School of Asian and African Area Studies, Kyoto
University) climbed a tree and lay on chimpanzee bed.
He found that it was amazingly comfortable. Ever since,
he has dreamt of sleeping on a bed like a chimpanzee

Figure 1. Human Evolution Bed. Megumi Kaji of the Research Association of Sleep andSociety lies on the bed at the Kyoto University Museum.

Pan Africa News, 23(2), December 201616

Figure 2. A chimpanzee day bed. Fimbi, a juvenile female
chimpanzee in Mahale, lying in the bed on December 21, 2010.

bed at home. He shared his idea about creating a chimpanzee bed on a human scale with the designer Shinichi
Ishikawa, and Arichika Iwata, a bedding product expert/
sleep environment instructor (IWATA Inc.), who showedinterest in supporting the project.
After much discussion and the production of two
prototypes, the Human Evolution Bed was made. When

Figure 3. The Human Evolution Bed (the 4th
prototype).

Zamma lay in it, he felt the same comfort as when in
the chimpanzee bed, or even more. This final prototype
was exhibited at the “Exhibition on Sleep: Evolution andDiversity of Material Cultures for Sleep” at the Kyoto
University Museum in 2016. Now we, the project team,are trying to make a final prototype that is durable andsuitable for the market.

<From the Editor>
From the next issue on, all contributors will be requested to add a DOI (Digital Object Identifier) number toevery reference whenever it is available (for a new referencing style, see References of the articles in this issue).
If you do not know how to get DOIs, go to the following URL:

http://www.crossref.org/guestquery/
Then you can look up DOIs only by filling in “First Author” (surname) and “Article Title”, and clicking the“Search” button.
PAN is planning to participate in CrossRef, which is the citation-linking system for online publications,
thanks to the assistance of the Kyoto University Library Network. CrossRef members have an obligation to linkreferences in the journal articles they deposit via CrossRef. Participation in CrossRef will benefit contributors in
two ways. First, it will give DOIs not only to future articles but also to all the back number articles. Second, it
will enhance online visibility of PAN articles. We hope more and more scholars can find and access PAN articles
while reading other online journal articles or PDFs published by other CrossRef member publishers.
Pan Africa News, Vol. 23, No.2
Published in December, 2016
Address: c/o Human Evolution Studies,
Dept. of Zoology, Faculty of Science,
Kyoto Univ., Kyoto, 606-8502, JAPANTEL: (+81)75-753-4108
FAX: (+81)75-753-4115
E-mail: pan.editor@gmail.com
URL: http://mahale.main.jp/PAN/
ISSN: 1884-751X (Print), 1884-7528 (Online)