Generation of a novel wing colour pattern by the Wingless morphogen

Area of Science:

• Developmental biology
• Evolutionary biology
• Animal coloration

Background:

• Animal color patterns are crucial for behavior and ecology.
• Mechanisms of color pattern formation and evolution are poorly understood.
• The spotted wing pattern of Drosophila guttifera presents a model for studying pattern development.

Purpose of the Study:

• To investigate the developmental mechanisms underlying the spotted wing pattern of Drosophila guttifera.
• To explore the evolutionary pathways that led to the complex spot pattern.
• To determine the role of the Wingless morphogen in pattern generation.

Main Methods:

• Analysis of gene expression patterns during wing development.
• Genetic manipulation to study the function of the Wingless morphogen.
• Comparative analysis of wing patterns across related species.

Main Results:

• Wing spots in Drosophila guttifera are induced by the Wingless morphogen.
• Wingless expression sites are determined by pre-existing positional information.
• The complex spot pattern evolved through the co-option of Wingless expression at new sites.
• The evolutionary process involves layering new patterns onto pre-existing developmental frameworks.

Conclusions:

• The Wingless morphogen is a key factor in generating the spotted wing pattern of Drosophila guttifera.
• Evolution of complex patterns can occur through the gradual addition of new developmental cues.
• This mechanism of pattern evolution by "layering" may be widespread in the animal kingdom.