Chimpanzee vertebrate consumption: Savanna and forest chimpanzees compared

Area of Science:

• Paleoanthropology
• Primatology
• Evolutionary Biology

Background:

• Meat-eating is considered crucial in human evolution, but its drivers remain debated.
• A hypothesis links increased animal food consumption (faunivory) to hominin adaptation in open savanna environments.
• It's suggested that savanna-dwelling chimpanzees might eat more meat than forest dwellers, supporting this link.

Purpose of the Study:

• To investigate if savanna chimpanzees consume vertebrates more frequently than forest chimpanzees.
• To compare the types and seasonality of vertebrate consumption between savanna and forest chimpanzee populations.
• To assess the implications of these findings for understanding early hominin behavior and evolution.

Main Methods:

• Observational data collection on vertebrate consumption in Tanzania's Ugalla region.
• Fecal analysis to identify consumed vertebrate species.
• Quantitative comparison of consumption rates, prey size, sharing patterns, and seasonality with published data from forest chimpanzee populations.

Main Results:

• Savanna chimpanzee populations showed no significant difference in overall vertebrate consumption rates compared to forest populations.
• Savanna chimpanzees consumed smaller vertebrates, which were less frequently shared.
• Vertebrate consumption by savanna chimpanzees was more seasonal than in forest populations.

Conclusions:

• The hypothesis that open habitats inherently promote higher faunivory in hominoids is not supported by this study.
• Focusing solely on forest monkey hunting may be misleading for modeling early hominin faunivory in open environments.
• Hominin faunivory increases likely relate to distinctions between hominins and chimpanzees or environmental differences between modern and Pliocene savannas.