Physically disabled primates find ways to modify their behavior to compensate for their disabilities

Behavioral responses to physical impairment and disability among free-ranging Japanese macaques at the Awajishima Monkey Center: (a) Adult male (Gatsu) without hands and feet with malformation, habituated bilaterally on the roof of a structure. Monkey center walking in style; (b) Adult male (gatsu) leaping from the wall; (c) An adult person with manual disability holds a piece of sweet potato and eats it. (d) A group of disabled and non-disabled monkeys that develop socially. (e) Young woman (Monmo) with extensive deformity of all four limbs walks quadrupedally using her elbows. (f) disabled adult women groom a non-disabled individual, using disability-specific grooming gestures; (g,h) Non-disabled adult male (Propeller) holding and grooming disabled infant (Nina) while Nina’s mother (Kimodoki) sits nearby (photos by BMS); (i) Adult female (Pikaru) with severely deformed hands pinches grain in a feeding gesture specific to the disability. (Images by SET unless otherwise indicated). Credit: American Journal of Primatology (2023). DOI: 10.1002/ajp.23579

Primates show a remarkable ability to modify their behavior to accommodate their physical disabilities and impairments, according to a new literature review by Concordia researchers.

Whether the disability was the result of birth defects or injuries, many primate species exhibited and innovation to compensate for their disabilities. They also benefit from their mothers’ flexible and innovative behavior early in life and from their peers in the population group as they age.

Researchers at the Primatology and Interdisciplinary Environmental Studies (PIES) lab looked at 114 studies and published their findings. American Journal of Primatology.

The survey also revealed something the researchers didn’t expect.

“Brogan Stewart, a PhD candidate, and lead author of the paper, noticed that a high proportion of the papers Co-corresponding author Sarah Turner, an associate professor in the Department of Geography, Planning, and the Environment in the Faculty of Arts and Sciences, says the potential or actual cause of the deterioration.

“Disability can be the result of snaring by other animals or by farmers trying to prevent crop forage. It may be the result of vehicle collisions, or sometimes the genetics of small populations and transmissible defects or “There are links between diseases. People or pollutants in the environment.”

The study consulted between 1931 and 2023 and identified 125 species. Chimpanzees were the most frequently studied, accounting for 25% of subjects. Other frequently recognized species include Japanese macaques, rhesus macaques, crab-eating macaques, and olive baboons.

More than 90 percent of disabilities were identified as impairments, injuries, or diseases or conditions. Macaques were the subjects of the largest number of studies on impairment, while chimpanzees were the subjects of the largest number of studies on injuries and diseases or conditions.

The researchers identified three themes in the literature they surveyed:

  • The central role of behavioral flexibility: Despite being physically crippled or maimed, primates were able to adjust their species-specific behaviors to survive, reproduce, and thrive. For example, some chimpanzees have been observed using two or three limbs for locomotion instead of their usual four.
  • Importance of maternity and special care and : While all primates need their mothers early in life, mothers of disabled children will provide additional care and modify their behavior to meet the needs of their offspring. Likewise, other people in their group will sometimes modify their own specific care to support a disabled participant. For example, one Japanese macaques adopt a young orphaned disabled monkey and take it with them as they move on three limbs during a group trip.
  • Ability to innovate: Disabled primates were observed developing new ways to participate in grooming, carrying and feeding their offspring. These usually involved new ways of using their limbs, such as pinching branches with their arms against their torsos for food.

For Turner and his team, the findings open up new avenues of research and provide valuable insight into the adaptive capacities of primates, their resilience, and the many unexpected effects of human activities on nonhuman animals.

“Some of the individuals at the Awajishima Monkey Center, where we do our fieldwork, are very physically impaired, but they are living their lives and doing things that other monkeys do,” says Turner. “They find ways to modify their behaviors such as unique patterns of locomotion, ways of carrying their infants, foraging and feeding techniques and individual styles of social grooming—compensating for physical defects. took.”

Stewart added, “We’re left to wonder if there’s a cost to the physical impairment for them? And when they’re compensating for them, is there a cost? I’m in my Ph.D. “I am researching the behavioral patterns associated with Japanese macaques with physical disabilities. Hopefully this research will give us more insight into the consequences of disabilities for free-ranging and wild primates.”

More information:
Brogan M. Stewart et al, Primates and disability: Implications of behavioral resilience and resilience to environmental change, American Journal of Primatology (2023). DOI: 10.1002/ajp.23579

Reference: Physically disabled primates find ways to modify their behavior to compensate for disability, researchers find (2024, Feb. 20) February 20, 2024 https://phys.org/news/2024-02- Retrieved from physically-impaired-primates-ways-behaviors.html

This document is subject to copyright. No part may be reproduced without written permission, except for any fair dealing for the purpose of private study or research. The content is provided for informational purposes only.