Yes, tigers do have stripes on their skin. The stripes are actually “in” and “on” the skin. This is because, as I understand it, even when a tiger’s fur has been shaved there remains a small segment of hair shaft inside the hair follicle (and just above it), embedded into the skin. This hair shaft has pigment in it as dictated by the tiger’s inherited genes and as deposited by pigment producing cells (melanocytes) in the hair follicle, which I discuss below. It is the same effect to what we see when a dark-haired man shaves. Even fully shaved there will be a “shadow”. It is the same for tigers if and when you shave off their fur as seen in the photos below:
Therefore, just like any other cat, the pattern on their fur is the same in their skin. This characteristic of the cat anatomy (and I believe the anatomy of any other furred mammal) can clearly be seen all the time with the Sphynx cat, which is hairless. You will see bicolour Sphynx cats with a pattern on their skin which replicates what they would have had on their fur if they were not hairless.
Melanocytes – pigment producing cells in the skin
The accurate science is quite tricky. However, I will do my best as a non-scientist to explain the basics. In the bottom layer of the skin’s epidermis there are cells called melanocytes. They produce pigment called melanin. Melanin is basically dark brown, almost black, but it’s colour varies depending on genetic influences. It can therefore be yellow in colour or orange as for the tiger. The colour of the pigment deposited in each individual hair shaft is either nearly black or orange. Genetics control the formation of the stripes against the orange background colour.
Melanocytes are present in all animals including humans. They are also present in hair follicles. The hair follicle is found in mammalian skin. It is in the dermal layer of the skin. It regulates hair growth and as I understand it, the pigment producing cells deposit pigment into the hair shaft as it grows.
Controlling the pattern
The inherited genes of the tiger controls how the pigment is deposited in the hair shafts. The genes also control the distribution of each hair strand in the coat. This produces the pattern in the hair. The tiger’s genes also control how the melanocytes deposit pigment in the skin.
The gene which produces the orange pigmentation is W (some older sources use the symbol “O” for this gene). The gene which controls the striping on the tiger is signified by the letter “S“. The genes which produce the coat on the classic orange and black striped tiger are usually “WWSS” indicating a dominant orange coat and dominant dark stripes. I would recommend that you visit the website of Sarah Hartwell, messybeast.com, which discusses the genetics in detail if you’re interested. She is the best at this. Each tiger has a unique pattern which allows a tiger to be indentified.
- How many stripes do tigers have?
- Why are white tigers white?
- Tiger stripes – some detailed information