Is it true that only cats can be tricolor, not cats? - briefly
No, it is not true that only cats can be tricolor; dogs can also exhibit this coat color pattern. The genetic basis for tricolor coats is similar in both species, involving the presence of two colors and the dilution of one of them to create a third.
Is it true that only cats can be tricolor, not cats? - in detail
The notion that only felines, specifically domestic cats, can exhibit tricolor coats is indeed a common misconception. While it is true that domestic cats are well-known for their tri-colored fur patterns—commonly referred to as calico in the United States and tortoiseshell elsewhere—this distinctive coloration is not exclusive to felines. In fact, various species across the animal kingdom can display tricolor coats, albeit with different frequencies and genetic mechanisms.
In domestic cats, the tricolor pattern is typically determined by the X chromosome. Female cats have two X chromosomes, which allows for the expression of three colors: black, orange, and white. Male cats, having only one X chromosome, usually exhibit less variation in coat color. However, other mammals can also exhibit tricolor coats through similar genetic processes or different evolutionary paths.
For instance, some breeds of dogs, such as the Australian Shepherd and the Cardigan Welsh Corgi, can display tricolor fur patterns. In these cases, the genetic mechanisms may differ from those in cats, but the visual result is similar. Additionally, certain species of horses, like the American Paint Horse, can exhibit tri-colored coats due to their unique genetic makeup.
Beyond mammals, birds such as the domestic chicken can also display tricolor feathers. In chickens, this is often a result of selective breeding and genetic variations that influence pigmentation. Even some fish species, like certain types of guppies, can exhibit tri-colored patterns due to their genetic makeup and environmental factors.
In conclusion, while domestic cats are frequently associated with tricolor coats, they are not the sole possessors of this distinctive trait. A variety of species across different animal groups can also exhibit tricolor patterns, each driven by unique genetic and evolutionary mechanisms.