Dynamic Changes in Begging Signal Short-Term Information on Hunger and Need

Area of Science:

• Behavioral Ecology
• Animal Communication
• Quantitative Genetics

Background:

• Dynamic signals convey information on different timescales, making signal change rate crucial for function.
• Offspring begging behavior in birds is a potential signal of need or quality to parents.

Purpose of the Study:

• Investigate if western bluebird begging behavior signals hunger, need, or quality.
• Determine the role of genetic and environmental factors in begging behavior variation.
• Assess the relationship between begging behavior and offspring fitness.

Main Methods:

• Repeatedly measured offspring begging behavior in western bluebirds.
• Assessed offspring fitness and condition.
• Conducted quantitative genetic analyses using cross-fostered offspring.

Main Results:

• Begging intensity increased with food deprivation, supporting the signal-of-hunger hypothesis.
• Begging intensity signaled need (nestlings in poorer condition begged more) but not quality.
• Begging behavior was flexible, influenced by the nest environment, not genetics.
• Begging intensity was repeatable only on short timescales and not strongly related to fitness.

Conclusions:

• Begging behavior dynamically signals shorter-term information: hunger and need.
• Signal timescale is important for understanding the function of begging behavior.
• Begging is a flexible trait shaped by the immediate environment rather than genetic predisposition.