Featured Research

from universities, journals, and other organizations

Chimpanzee ground nests offer new insight into our ancestors' descent from the trees

Date:
April 16, 2012
Source:
Wiley-Blackwell
Summary:
The first study into rarely documented ground-nest building by wild chimpanzees offers new clues about the ancient transition of early hominins from sleeping in trees to sleeping on the ground. While most apes build nests in trees, this study focused on a group of wild West African chimpanzees that often shows ground-nesting behavior.

Chimpanzee. Chimpanzee behaviour suggests that the tree-to-ground transition occurred before the emergence of ancient humans.
Credit: namatae / Fotolia

The first study into rarely documented ground-nest building by wild chimpanzees offers new clues about the ancient transition of early hominins from sleeping in trees to sleeping on the ground. While most apes build nests in trees, this study, published in the American Journal of Physical Anthropology, focused on a group of wild West African chimpanzees that often shows ground-nesting behaviour.

Related Articles


An international team of primatologists from the University of Cambridge and Kyoto University, led by Dr Kathelijne Koops, studied the chimpanzee (Pan troglodytes verus) population in the Nimba Mountains in Guinea, West Africa. All species of great ape build nests to sleep in each night. Construction of these shelters takes minutes as the apes bend, break and interweave branches into a circular frame, followed by tucking in smaller branches to form a sturdy but comfortable sleeping platform.

"We believe that, like modern apes, the common ancestor of chimpanzees and humans also slept in the trees 6 million years ago," said Dr Koops. "However, these nests are not preserved in the fossil or archaeological record, so it is impossible to study directly the ancient transition from sleeping in trees to building shelters on the ground. Recording this rare behaviour in the chimpanzee, our closest relative, may provide vital clues."

As the Nimba chimpanzees do not yet tolerate human presence at close range, the team used new molecular genetic techniques to analyse hairs collected from the nests. This allowed the team to establish the sex of chimpanzees displaying the behaviour and to identify individuals in the group.

The team showed that as chimpanzees sleep both on the ground and in the trees, the transition from trees to the ground did not require a special evolutionary adaptation. This suggests that early hominins may have slept on the ground before the emergence of Homo erectus ('upright man'), the first species which was fully adapted to living on the ground. "This is intriguing as it has long been believed that coming down from the trees was a crucial evolutionary shift," said Koops. "However, this chimpanzees' behaviour suggests a more deep-seated, gradual transition from tree-to-ground sleep."

Other theories for the tree-to-ground transition have included the use of fire and the scarcity of trees in open habitats. The team demonstrated that neither is a prerequisite for ground sleeping, as the chimpanzees live in a plentiful evergreen rainforest and do not create fire.

"These chimpanzees offer a rare opportunity to investigate why a population of wild apes chooses to sleep on the ground," concluded Koops. "We showed that ground-nesting was not caused by male mate-guarding behaviour, a lack of trees in which to nest, or because of fire. This suggests that our direct ancestors were neither the only, nor the first, species to come down from the trees."


Story Source:

The above story is based on materials provided by Wiley-Blackwell. Note: Materials may be edited for content and length.


Journal Reference:

  1. Kathelijne Koops, William C. McGrew, Tetsuro Matsuzawa, Leslie A. Knapp. Terrestrial nest-building by wild chimpanzees (Pan troglodytes): Implications for the tree-to-ground sleep transition in early hominins. American Journal of Physical Anthropology, 2012; DOI: 10.1002/ajpa.22056

Cite This Page:

Wiley-Blackwell. "Chimpanzee ground nests offer new insight into our ancestors' descent from the trees." ScienceDaily. ScienceDaily, 16 April 2012. <www.sciencedaily.com/releases/2012/04/120416113058.htm>.
Wiley-Blackwell. (2012, April 16). Chimpanzee ground nests offer new insight into our ancestors' descent from the trees. ScienceDaily. Retrieved November 23, 2014 from www.sciencedaily.com/releases/2012/04/120416113058.htm
Wiley-Blackwell. "Chimpanzee ground nests offer new insight into our ancestors' descent from the trees." ScienceDaily. www.sciencedaily.com/releases/2012/04/120416113058.htm (accessed November 23, 2014).

Share This


More From ScienceDaily



More Plants & Animals News

Sunday, November 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Anglerfish Rarely Seen In Its Habitat Will Haunt You

Anglerfish Rarely Seen In Its Habitat Will Haunt You

Newsy (Nov. 22, 2014) For the first time Monterey Bay Aquarium recorded a video of the elusive, creepy and rarely seen anglerfish. Video provided by Newsy
Powered by NewsLook.com
Birds Around the World Take Flight

Birds Around the World Take Flight

Reuters - Light News Video Online (Nov. 22, 2014) An imperial eagle equipped with a camera spreads its wings over London. It's just one of the many birds making headlines in this week's "animal roundup". Jillian Kitchener reports. Video provided by Reuters
Powered by NewsLook.com
Could Your Genes Be The Reason You're Single?

Could Your Genes Be The Reason You're Single?

Newsy (Nov. 21, 2014) Researchers in Beijing discovered a gene called 5-HTA1, and carriers are reportedly 20 percent more likely to be single. Video provided by Newsy
Powered by NewsLook.com
Raw: Baby Okapi Born at Houston Zoo

Raw: Baby Okapi Born at Houston Zoo

AP (Nov. 20, 2014) The Houston Zoo released video of a male baby okapi. Okapis, also known as the "forest giraffe", are native to the Democratic Republic of the Congo in Central Africa. Video is mute from source. (Nov. 20) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins