What practical safety function did the preference for a predominantly white coat serve in the field?

Answer

Distinguishing the terrier clearly from the reddish or dark-colored fox quarry underground.

While white may be aesthetically preferred in modern show rings, the historical drive toward a predominantly white coat was highly functional for field work. When the terrier successfully located the fox in the dark confines of the den, or when bolting out into brush, hunters needed an unmistakable visual marker. Since foxes are typically reddish or dark in coloration, a white dog offered maximum contrast, allowing handlers to clearly identify their dog immediately during fast-paced hunting situations, thus preventing accidental injury or confusion.

What practical safety function did the preference for a predominantly white coat serve in the field?
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