Which data source is commonly used to perform morphometric analysis in sticklebacks?

• A. Images or measurements.
• B. DNA sequences.
• C. Metabolic rate data.
• D. Nest site temperature data.

Answer: (A)

Morphometric analysis focuses on quantifying body shape and size, so the essential data come from direct measurements or images that capture those physical features. By using standardized photos or precise measurements (lengths, widths, angles, and outlines), you can extract landmarks or shape outlines and analyze variation in sticklebacks across individuals or populations. This approach lets you compare proportions, detect subtle shape differences, and study how morphology changes with scale or environment.

DNA sequences, metabolic rate data, and nest site temperature data each serve other kinds of questions—genetics, physiology, and environmental context—rather than the actual geometry of the fish. Therefore, images or measurements are the data source best suited for morphometric analysis.