Genetic differences in learning behavior in honeybees (Apis mellifera capensis).

Area of Science:

• Ethology
• Behavioral Genetics
• Neuroethology

Background:

• Phenotypic differences in honeybee worker performance, particularly in proboscis extension reflex (PER) conditioning, are well-documented.
• Understanding the genetic basis of these behavioral variations is crucial for insights into social insect cognition and evolution.

Purpose of the Study:

• To estimate genotypic values and quantify genetic variability in PER conditioning among Cape honeybee workers.
• To determine the relative contributions of additive and dominance genetic effects on associative learning.
• To investigate the impact of selection on genetic variance in subsequent generations.

Main Methods:

• Utilized parthenogenetic offspring groups for precise estimation of genotypic values.
• Conducted quantitative genetic analysis to assess additive and dominance effects.
• Employed selection experiments across generations (G1 and G2) to track changes in genetic variance.

Main Results:

• Revealed substantial genetic variability in PER conditioning, evident in both related and unrelated bees, including within the same colony.
• Quantitative analysis indicated high additive genetic effects and low dominance effects influencing learning performance.
• Selection on individual workers increased genetic variance in the G1 generation, but further selection in parthenogenetic G1 to G2 did not yield improvement, suggesting limited recombination.

Conclusions:

• Additive genetic factors play a significant role in individual differences in associative learning among honeybee workers.
• The genetic architecture of PER conditioning is characterized by substantial additive variance, amenable to selection.
• Limited recombination in parthenogenetic lines may constrain the effectiveness of selection over multiple generations.