Apostatic selection by humans searching for computer-generated images on a colour monitor

Area of Science:

• Behavioral Ecology
• Evolutionary Biology
• Visual Perception

Background:

• Predator-prey interactions are crucial in evolutionary biology.
• Apostatic selection, where predators avoid common prey types, is a key mechanism.
• The role of prey conspicuousness and detection difficulty in apostatic selection requires further investigation.

Purpose of the Study:

• To investigate the occurrence of apostatic selection in a controlled visual environment.
• To determine the influence of prey conspicuousness and detection difficulty on apostatic selection.

Main Methods:

• A computer program generated dimorphic prey populations on a color monitor.
• Subjects used a light pen to detect and remove prey presented at varying frequencies.
• Prey were displayed against either matching (inconspicuous) or contrasting (conspicuous) backgrounds.

Main Results:

• Apostatic selection was observed when prey were inconspicuous against a matching background.
• Apostatic selection did not occur when prey were conspicuous against a contrasting background.
• Evidence suggests that difficulty in detecting cryptic prey contributes to apostatic selection.

Conclusions:

• Prey inconspicuousness is a critical factor for apostatic selection to occur.
• The ease with which predators can detect prey influences the dynamics of natural selection.
• Detection difficulty, particularly for cryptic prey, may drive apostatic selection in predator-prey systems.