Not universally; there is no single dominant allele for black noses in wolves, as nose pigmentation appears to be polygenic and population-specific.
Explanation
Nose color in wolves is determined by pigment production in the nasal tissue, which is controlled by multiple genes involved in melanin synthesis and distribution (and potentially regulatory elements). Because several genes can influence the amount and distribution of pigment, a single dominant allele cannot reliably explain black noses across all wolf populations. Additionally, environmental factors (age, sun exposure, health) and interactions between genes (epistasis) can modulate the phenotype, leading to variation even within close populations. In contrast to a simple one-gene‑one‑trait model, nose pigmentation is best understood as a polygenic trait with complex inheritance patterns.
Key Points
- 1, Nose color is polygenic and influenced by multiple pigment-related genes rather than a single dominant allele.
- 2, There is no consistent, universal dominance pattern for black noses across all wolf populations; variation exists among individuals and populations.
- 3, Environmental and developmental factors can affect nose pigmentation, complicating simple Mendelian interpretations.