Interaction-Design-in-The-Wild
View the Project on GitHub svonhauske/Interaction-Design-in-The-Wild
Hyena Enrichment Prototype
by Sofia von Hauske Valtierra
Crocuta crocuta
Introduction
The Crocuta crocuta, more commonly known as spotted hyena, is the largest of three hyena species (striped hyena, brown hyena, and aardwolf). They appear to be similar to dogs, but more closely related to cats. They live throughout much of Africa, Arabia to India. Females lead spotted hyenas, and they live together in clans that may have up to 100 hyenas. Scientists have recorded over 11 different vocalizations made by spotted hyenas, making them the most vocal mammals in Africa.
The length from head to tail is about 95 to 150 cm and the height is about 75 cm to 85cm. The tail is about 30 to 36 cm long and ends in a bushy black tip. Male weight ranges from 45 to 60 kg and females weigh 55 to over 70 kg.
Sources: National Geographic, San Diego Zoo, AWD
Hunting Behavior:
Hyenas do not kill their prey directly; the prey is captured and eaten while still alive. The victim dies from shock and loss of blood as it is torn apart and pulled down. They have different hunting techniques based on the size and type of prey. They get up to 75% of their food from their own kills. The spotted hyena tracks live prey by sight, hearing and smell.
• Big Prey: When hyenas hunt an animal that is bigger than themselves, they hunt more like a dog or wolf, hunting down the prey as a group. They take down the prey by biting into it and pulling it into the ground. Examples: wildebeest, antelope, zebras and young hippos.
Video: Hyenas Hunting Antelope
• Small Prey: When hunting weak or smaller prey, they hunt individually. Examples: birds, fish, snakes, lizards and insects.
Previous Enrichment Testing
Innovative Problem Solving by Wild Spotted Hyenas
by Sarah Benson-Amram and Kay E. Holekamp
At the Department of Zoology of Michigan State University, they wanted to test whether the Crocuta crocuta is an innovative animal, which is an animal able to solve new problems or find new solutions to existing problems. The study was conducted in their natural habitat in the Masai Mara National Reserve, Kenya. They built a steel puzzle box that was presented to the hyenas. It was big enough to allow for a hyena to put its head inside the box, and the spacing between the bars of the box was sufficient to allow hyenas to see and smell the meat inside. To be able to reach the meat, the hyena would have to slide a bolt latch laterally, and swing open the door; it could be opened using either the mouth or the forepaws.
Spotted hyenas are incredibly adept at solving social problems, but only 15% of them managed to solve open the box. Those successful hyenas became faster at opening the puzzle box over successive trials. This study showed that hyenas learn via trial and error.
Juveniles showed greater exploration diversity, spent more time working on the puzzle and were less neophobic than adults. Neither sex nor social rank affected exploration diversity, work time, or neophobia.
Hyena Project
by Lily Johnson-Ulrich
Lily Johnson-Ulrich starts her research with thinking that because neural tissue is costly, people have agreed that big brains must be adaptive. One of the most conventional explanations for the evolution of intelligence is the Social Brain Hypothesis, which argues that intelligence did not evolve primarily as a means to solve ecological problems, but rather as a means of surviving and reproducing in large and complex social groups. This hypothesis has been strongly supported by work on primates where higher degrees of social complexity are correlated with enhanced social cognition. The cognitive buffer hypothesis suggests that big brains enhance overall behavioral flexibility and allow individuals to respond effectively to rapidly changing or novel environments. Johnson-Ulrich is testing out predictions of the SBH and CBH hypotheses by testing two cognitive abilities: innovation and inhibitory control, in spotted hyenas.
Hyenas exhibit larger overall brains and proportionally larger frontal cortex than those seen in other extant hyenas or other carnivores. The size of their frontal cortex and the similarity between hyena and primate societies predict that hyenas should do comparably well on cognitive tasks.
This is an ongoing research project that hasn’t been published yet, but I have added some in the field photographs.
Sources: Social intelligence in the spotted hyena (Crocuta crocuta), Brain size and social complexity: a computed tomography study in Hyaenidae., Brains, brawn and sociality: a hyaena’s tale, Sex and the frontal cortex: A developmental CT study in the spotted hyena.
Problem Solving and Social Learning In Spotted Hyenas (Crocuta crocuta)
by Lindsay M. Kubina
Social Complexity Hypothesis: Same as the social brain hypothesis, which proposes that the advanced social and cognitive skills of some species evolved due to the selection pressure of group living. Spotted hyenas have advanced social cognitive abilities similar to primates, for example, being able to identify individuals within their clan, recognize kin, and learn about social ranks of other clan members.
The spotted hyenas problem solving was tested by presenting six-spotted hyenas with a series of puzzle boxes. All of the test subjects were similar in size and had been in a zoo for about three years. The animals were given 30 to 40 minutes to solve each puzzle.
• Remove Bowl Puzzle: Solved by all hyenas.
• Puzzle Box:
• Cable Puzzle:
• Lazy Susan Puzzle: Solved by all hyenas.
• Remove Lid Puzzle:
• Plunger Puzzle: Solved by only one hyena.
Overall the spotted hyenas were capable of solving the majority of the puzzle boxes. All of the spotted hyenas solved puzzles with a low level of difficulty where they simply had to pull the bowl out of the front of the box with their paw or mouth. Success was more variable when it came to medium difficulty puzzles where the solution involved a type of pulling motion either with the mouth or paws. They were generally unsuccessful at solving the high difficulty puzzle like the Plunger Puzzle that required the food to be pushed away from them to be accessed.
Sources: Vocal recognition in the spotted hyaena and its possible implications regarding the evolution of intelligence, A comparison of innovative problem-solving abilities between wild and captive spotted hyaenas, Crocuta crocuta
Prototype
Based on the previous findings, we wanted to design a device that would use a hyena’s ability to bite down hard and pull, their cooperative behavior and their ability to problem solve. This prototype looks to create a food interaction but also a social interaction.
We designed a container that has a box on the inside where the hyena’s food is contained. The bottom of the container can be changed and each bottom can have a different number of holes, each one a different size, making it more or less challenging to get the food. The inner box is attached to ropes that hang from the sides of the container and they can slide left or right on every side of the container. These slits allow the ropes to move and pull the box around inside the container. There is a small door at the top, where food can be inserted by lining up the inner box with the container door.
The container is hung slightly above the hyena’s heads, adding a little more difficulty to the hyenas by not being perfectly still. Although this could be placed both in the wild and in a zoo environment, like some of the enrichment tests shown above, these tests have shown that captive animals engage with this type of enrichment more than wild animals do, so we believe it is more suitable for a zoo environment.
Hyenas have to pull the ropes on every side to move the box around and try to match the inside box with one of the bottom holes so that food starts coming out. The idea is that 2 or more hyenas cooperate by pulling from different ropes at the same time to get the food faster, but the same outcome can be achieved by a single hyena in case that there is only one found at the zoo, which is the case in some places.
Things to Reassess
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Hanging or Standing: By having it hang it might be too difficult for the hyenas to pull because if the container doesn’t slide properly inside the box, they could just be pulling the box instead of the container. The swinging of the box might also be dangerous because it could hit a hyena. A steel platform could be built so it holds the container above the hyenas, but it sits perfectly still instead of swinging.
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Materials: Hyenas are so strong, that it might be better to make the box and the container out of metal which would also help with the sliding because there would be no friction.
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Tray cutouts: The different cutouts can change in size and location, changing the difficulty of the puzzle.
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Size: The size of the box and the container might need to change, depending on whether this is used for feeding or treats. Hyenas are sometimes fed big animals which would require more room.