Fallback foods, eclectic omnivores, and the packaging problem

Area of Science:

• Primate Ecology
• Nutritional Ecology
• Behavioral Ecology

Background:

• Selective omnivores, including primates, must manage dietary intake due to nutrient variability and food-associated toxins.
• The "packaging problem" highlights the challenge of obtaining adequate nutrition when costs and benefits of food sources are imbalanced, especially with seasonal fallback foods.

Purpose of the Study:

• To survey and categorize the adaptations omnivorous primates employ to cope with the packaging problem and the use of fallback foods.
• To examine adaptations across behavioral, anatomical, physiological, and life history domains.

Main Methods:

• Review and synthesis of existing literature on primate feeding ecology and adaptations.
• Categorization of 16 distinct types of adaptations related to fallback food utilization and the packaging problem.

Main Results:

• Behavioral adaptations include cost minimization, exploiting food availability, social learning, and home range shifts.
• Anatomical and physiological adaptations encompass generalized digestive systems, enhanced sensory perception (e.g., color vision), physical agility, and internal nutrient storage or synthesis.
• Life history adjustments involve changes in parental investment, interbirth intervals, breeding seasonality, and even fetal resorption.

Conclusions:

• Omnivorous primates display a comprehensive suite of interconnected adaptations to overcome the challenges posed by nutrient variability and food toxins, particularly when relying on fallback foods.
• These adaptations operate at multiple biological levels, demonstrating the complex evolutionary strategies primates use to ensure survival and reproduction in diverse environments.