Lateralization of tool use in New Caledonian crows (Corvus moneduloides)

Area of Science:

• Comparative psychology
• Animal behavior
• Neuroscience

Background:

• Tool use is a complex cognitive ability observed in various animal species.
• Laterality, or the preference for using one side of the body, is a well-documented phenomenon in humans and some animals.
• New Caledonian crows (Corvus moneduloides) are known for their sophisticated tool-making and tool-using behaviors.

Purpose of the Study:

• To investigate the laterality of tool use in captive New Caledonian crows.
• To determine if there is a population-level bias in tool use laterality within this species.
• To compare tool use laterality with tool manufacture laterality in New Caledonian crows.

Main Methods:

• Studied laterality of tool use in 10 captive New Caledonian crows.
• Assessed individual tool use preferences (left or right lateralization).
• Analyzed population-level biases in tool use laterality.

Main Results:

• All 10 subjects displayed near-exclusive individual laterality in tool use.
• There was no overall population-level bias, with five crows being left-lateralized and five being right-lateralized.
• These findings align with previous studies on tool use laterality in primates and wild New Caledonian crows.

Conclusions:

• Individual tool use laterality is a consistent trait in New Caledonian crows.
• The lack of population-level bias in tool use contrasts with observed population-level bias in tool manufacture.
• This divergence suggests distinct neural underpinnings for tool manufacture and tool use in New Caledonian crows.