Endocrine and epigenetic flexibility in an African starling

Area of Science:

• Animal Behaviour
• Endocrinology
• Epigenetics

Background:

• Organisms adjust behavior and physiology to environmental changes, but trait flexibility, timescales, and environments remain unclear.
• Superb starlings (Lamprotornis superbus) from East African savannas, arid, and mesic habitats were studied.
• Endocrine (glucocorticoid hormones) and epigenetic (DNA methylation) flexibility were explored.

Purpose of the Study:

• To investigate endocrine and epigenetic flexibility in superb starlings.
• To determine how captivity affects corticosterone levels and DNA methylation.
• To assess the reversibility of these changes over time.

Main Methods:

• Captured superb starlings from three Kenyan sites (desert margin, savanna bushland, forest margin).
• Housed birds under common garden conditions for six months.
• Measured baseline and stress-induced corticosterone and quantified genome-wide DNA methylation at capture, 3, and 6 months.

Main Results:

• Captivity increased baseline corticosterone and decreased DNA methylation in developmental genes.
• Stress-induced corticosterone levels did not change significantly.
• After six months, corticosterone and most DNA methylation patterns returned to pre-captivity levels.

Conclusions:

• Semi-arid dwelling birds exhibit flexible endocrine and epigenetic responses to captivity.
• These physiological and epigenetic adjustments are reversible over time.
• This highlights the adaptability of superb starlings to environmental stressors.