Newborn chicks show inherited variability in early social predispositions for hen-like stimuli

Area of Science:

• Ethology
• Behavioral Genetics
• Developmental Neuroscience

Background:

• Newborn vertebrates exhibit innate predispositions to attend to and learn about living beings.
• Disruptions in these predispositions, as seen in neonates at risk for autism, can impair social brain development.
• The genetic underpinnings of these early social predispositions remain largely unknown.

Purpose of the Study:

• To investigate the presence of segregating genetic variation in predispositions to approach social stimuli in newly-hatched chicks (Gallus gallus).
• To explore potential genetic bases for early social learning and behavioral responses to social cues.

Main Methods:

• Utilized newly-hatched chicks from three genetically isolated breeds (Padovana, Polverara, Robusta maculata) raised identically.
• Assessed spontaneous visual preferences of visually-naïve chicks towards a stuffed hen versus a scrambled version of it.
• Compared breed-specific behavioral responses and exploration strategies over time.

Main Results:

• All breeds initially showed a consistent preference for the intact hen stimulus, suggesting a genetically fixed initial preference.
• Significant breed differences emerged after a few minutes, indicating varying exploration strategies towards the stimuli.
• The Polverara breed maintained preference, while Padovana and Robusta breeds increased exploration of the alternative stimulus.

Conclusions:

• Documented inherited genetic variability in the expression of early social predispositions.
• Demonstrated that genetic factors influence how chicks interact with and explore social stimuli.
• Highlighted the role of genetic diversity in shaping early social behavioral strategies.