Nav: Home

Re-inventing the hook

November 08, 2018

The bending of a hook into wire to fish for the handle of a basket is surprisingly challenging for young children under eight years of age. Now cognitive biologists and comparative psychologists from the University of Vienna, the University of St Andrews and the University of Veterinary Medicine Vienna around Isabelle Laumer and Alice Auersperg studied hook tool making for the first time in a non-human primate species - the orangutan. To the researchers' surprise the apes spontaneously manufactured hook tools out of straight wire within the very first trial and in a second task unbent curved wire to make a straight tool.

Human children are already proficient tool-users and tool-makers from an early age on. Nevertheless, when confronted with a task, which required them to innovate a hooked tool out of a straight piece of wire in order to retrieve a basket from the bottom of a vertical tube, the job proved more challenging for children than one might think: Three to five-year-old children rarely succeed and even at the age of seven less than half of them were able to solve the task. Only at the age of eight the majority of children was able to innovate a hook-tool. Interestingly children of all tested age classes succeeded when given demonstrations on how to bend a hook and use it. Thus, although young children apparently understand what kind of tool is required and are skilled enough to make a functional tool, there seems to be a cognitive obstacle in innovating one.

Cognitive biologists and comparative psychologists from the University of Vienna, the University of St Andrews and the University of Veterinary Medicine in Vienna around Isabelle Laumer now tested for the first time a primate species in the hook-bending task. "We confronted the orangutans with a vertical tube containing a reward basket with a handle and a straight piece of wire. In a second task with a horizontal tube containing a reward at its centre and a piece of wire that was bent at 90°", explains Isabelle Laumer who conducted the study at the Zoo Leipzig in Germany. "Retrieving the reward from the vertical tube thus required the orangutans to bent a hook into the wire to fish the basket out of the tube. The horizontal tube in turn required the apes to unbent the bent piece of wire in order to make it long enough to push the food out of the tube."

Several orangutans mastered the hook bending task and the unbending task. Two orangutans even solved both tasks within the first minutes of the very first trial. "The orangutans mostly bent the hooks directly with their teeth and mouth while keeping the rest of the tool straight. Thereafter they immediately inserted it in correct orientation, hooked the handle and pulled the basket up", she further explains.

Orangutans share 97% of their DNA with us and are among the most intelligent primates. They have human-like long-term memory, routinely use a variety of sophisticated tools in the wild and construct elaborate sleeping nests each night from foliage and branches. Today orangutans can only be found in the rainforests of Sumatra and Borneo. Like all four great ape species, orangutans are listed as critically endangered (IUCN, Red List). "Habitat loss due to extensive palm-oil production, illegal wildlife trade and poaching are the major threats. Palm oil is the most widely used vegetable oil in the world. As long as there is a demand for palm oil and consumers keep buying products that contain palm oil, the palm industry thrives. According to a 2007 survey by the United Nations Environment Program (UNEP) orangutans will be extinct in the wild within two decades if current deforestation trends continue", says Isabelle Laumer.

"The hook-bending task has become a benchmark paradim to test tool innovation abilities in comparative psychology", says Alice Auersperg from the University of Veterinary Medicine in Vienna. "Considering the speed of their hook innovation, it seems that they actively invented a solution to this problem rather than applying routined behaviours."

"Finding this capacity in one of our closest relatives is astonishing. In human evolution hook tools appear relatively late. Fish hooks and harpoon-like, curved objects date back only approximately 16.000- 60.000 years. Although New Caledonian crows use hooks with regularity, there are a few observations of wild apes, such as chimpanzees and orangutans, that use previously detached branches to catch and retrieve out-of-reach branches for locomotion in the canopy. This branch-hauling tools might represents one of the earliest and simplest raking tools used and made by great apes and our ancestors", says Josep Call of the University of St Andrews.

So why struggle younger children with this task? "Follow-up studies showed that childrens difficulty with independently finding the solution cannot be explained by fixedness on unmodified tools, impulsivity nor by not being able to change the strategy. The hook bending task represents a complex problem, for which several unrewarded steps must be performed while keeping the final goal in mind", explains Isabelle Laumer. "Interestingly, complex problem solving has been associated to certain areas of the medial prefrontal cortex, which mature later in the child development. This explanation, besides children´s strong reliance on social learning might explain their success at a later age."
-end-
Publication in Scientific Reports: Laumer I.B., Call J., Bugnyar T., Auersperg A.M.I "Spontaneous innovation of hook-bending and unbending in orangutans (Pongo abelii)" DOI: 10.1038/s41598-018-34607-0

On publication, the paper will be freely available online at http://www.nature.com/articles/s41598-018-34607-0

University of Vienna

Related Orangutans Articles:

Orangutans suckle for up to eight years, teeth reveal
Researchers have developed a method for tracking characteristically elusive nursing patterns in primates and used it to discover that some immature orangutans suckle for eight years or more -- exceeding the maximum weaning age reported for other non-human primates.
Wild orangutan teeth provide insight into human breast-feeding evolution
Biomarkers in the teeth of wild orangutans indicate nursing patterns related to food fluctuations in their habitats, which can help guide understanding of breast-feeding evolution in humans, according to a study published today in Science Advances.
Study could provide first clues about the social lives of extinct human relatives
A new study from The Australian National University (ANU) of the bony head-crests of male gorillas could provide some of the first clues about the social structures of our extinct human relatives, including how they chose their sexual partners.
Like people, great apes may distinguish between true and false beliefs in others
Great apes help a person access an object when that person thinks they knows where it is but is mistaken, according to a study published April 5, 2017 in the open-access journal PLOS ONE by David Buttelmann from Max Planck Institute for Evolutionary Anthropology, Germany, and colleagues.
From Beethoven to Bieber, why playing music to chimps is falling on deaf ears
Playing music to captive chimpanzees has no positive effect on their welfare, researchers have concluded.
New broad-spectrum antiviral protein can inhibit HIV, other pathogens in some primates
University of Colorado Boulder researchers have discovered that a protein-coding gene called Schlafen11 (SLFN11) may induce a broad-spectrum cellular response against infection by viruses including HIV-1.
Exploring the evolutionary history of the immune system
Researchers from Charité - Universitätsmedizin Berlin have found that human ALOX15 appears to have developed a much higher capacity to stimulate the production of these lipid mediators than the enzyme variant found in lower primates.
Apes understand that some things are all in your head
Bonobos, chimpanzees and orangutans understand that others can be convinced of something that is not true.
Apes demonstrate human-like understanding of what others believe
Apes can correctly anticipate that humans will look for a hidden item in a specific location, even if the apes know that item is no longer there, a new study reveals.
Apes understand that some things are all in your head
We all know that the way someone sees the world, and the way it really is, aren't always the same.

Related Orangutans Reading:

Orangutans: Behavior, Ecology, and Conservation (The MIT Press)
by Junaidi Payne (Author), J. Cede Prudente (Author)

Orangutan (A Day in the Life: Rain Forest Animals)
by Anita Ganeri (Author)

Orangutans My Cousins, My Friends: A journey to understand and save the person of the forest
by The Orangutan Project

Reflections of Eden: My Years with the Orangutans of Borneo
by Birute M. F. Galdikas (Author)

Orangutans (Nature's Children Animals in Danger!)
by Mara Grunbaum (Author)

Orangutan: Children Book of Fun Facts & Amazing Photos on Animals in Nature - A Wonderful Orangutan Book for Kids aged 3-7
by Ina Felix (Author)

Decolonizing Extinction: The Work of Care in Orangutan Rehabilitation (Experimental Futures)
by Juno Salazar Parreñas (Author)

Orangutan: A Day in the Rainforest Canopy
by Dancing Dakini Press

Curious About Orangutans (Smithsonian)
by Gina Shaw (Author)

Orangutan Houdini
by Laurel Neme (Author), Kathie Kelleher (Illustrator)

Best Science Podcasts 2018

We have hand picked the best science podcasts for 2018. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Unintended Consequences
Human innovation has transformed the way we live, often for the better. But as our technologies grow more powerful, so do their consequences. This hour, TED speakers explore technology's dark side. Guests include writer and artist James Bridle, historians Yuval Noah Harari and Edward Tenner, internet security strategist Yasmin Green, and journalist Kashmir Hill.
Now Playing: Science for the People

#499 Technology, Work and The Future (Rebroadcast)
This week, we're thinking about how rapidly advancing technology will change our future, our work, and our well-being. We speak to Richard and Daniel Susskind about their book "The Future of Professions: How Technology Will Transform the Work of Human Experts" about the impacts technology may have on professional work. And Nicholas Agar comes on to talk about his book "The Sceptical Optimist" and the ways new technologies will affect our perceptions and well-being.