Maternal age at maturation underpins contrasting behavior in offspring

Area of Science:

• Behavioral Ecology
• Evolutionary Biology
• Reproductive Strategies

Background:

• Parental age influences offspring fitness in species with egg provisioning.
• Offspring size is a known factor, but other maternal age effects on fitness exist.
• Parental age at maturation is a key life-history trait with potential impacts on offspring.

Purpose of the Study:

• To investigate size-independent effects of maternal age at maturation on offspring behavior in Atlantic salmon.
• To determine if offspring behavior variation is linked to maternal maturation age, paternal age, or both.
• To provide the first evidence of a link between natural variation in parental age at maturation and offspring behavior.

Main Methods:

• Experimental matings of wild Atlantic salmon with varying maturation ages.
• Observation of juvenile salmon behavior in competitive feeding territory scenarios.
• Analysis of offspring behavior (aggression, food competition) in relation to maternal and paternal maturation age.

Main Results:

• Offspring behavior varied significantly based on maternal maturation age, independent of offspring size.
• Juvenile salmon from early-maturing mothers exhibited higher aggression levels.
• Offspring from late-maturing mothers out-competed those from early-maturing mothers for food resources.

Conclusions:

• Maternal age at sexual maturation is a significant factor influencing offspring behavior in Atlantic salmon.
• Size-independent behavioral differences in offspring can arise from variation in maternal age at maturation.
• This study reveals a novel link between parental life-history traits and offspring behavioral ecology.