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Only female cats can be tortoiseshell because the coat colour gene is sex-linked & in all cells one X chromosome becomes inactive. Each allele is either black or orange & because the process is random it results in orange and black patches across the body

A Polar Bear Ursus Maritimus Resting by Richard Wear - A Polar Bear Ursus Maritimus Resting Photograph - A Polar Bear Ursus Maritimus Resting Fine Art Prints and Posters for Sale