A non-adaptationist hypothesis of play behaviour

Area of Science:

• Ethology
• Neuroscience
• Systems Biology

Background:

• Play is a common behavior in animals, but its evolutionary origins remain unclear.
• Existing adaptationist theories lack sufficient supporting evidence.
• Recent advances in evolutionary synthesis and systems biology open new non-adaptationist research avenues.

Purpose of the Study:

• To propose a novel, non-adaptationist hypothesis for the evolution of play.
• To link play behavior to complex acetylcholine (ACh) activity and its physiological roles.
• To explain the variable occurrence of play across different species and taxa.

Main Methods:

• The study proposes a hypothesis based on existing biological and evolutionary theories.
• It integrates concepts from systems biology and the extended evolutionary synthesis.
• It does not detail experimental methods but outlines a theoretical framework for future research.

Main Results:

• Play is hypothesized to involve ACh-mediated feedforward and feedback processes.
• These processes regulate metabolism, receptor formation, learning, and social behaviors.
• Potential explanations for play's variable occurrence include biases and developmental/environmental factors.

Conclusions:

• The proposed ACh-based hypothesis offers a new framework for understanding play's evolution.
• It highlights the physiological underpinnings of play behavior.
• This hypothesis encourages further research in biological, social, and applied sciences, including animal welfare and biomedicine.