Nature
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Dalmatians are famous for their spots, but did you know that when they come into the world as puppies, all dalmatians have pure white coats? Dalmatian spots actually don’t start to develop until 10 to 14 days after birth, but the number and size of the spots are still predetermined.
As a dog breed selected for by humans, dalmatian spots serve no evolutionary purpose – but how, when, and why they emerge is a curious topic that scientists have delved into.
Why do dalmatians get spots?
The pattern of dalmatian spots has intrigued scientists, who have been able to determine that the distinctive coat is the result of interactions at several genetic loci. One is the Piebald locus that can give rise to animals with pigment-free patches across their coat, scales, or skin.
Piebald animals can have patterns like Percy, pictured below. Percy is a ball python with piebaldism who lives with our Social Media and Marketing Assistant Charlie Haigh, and looks like he’s been dipped up to his neck in yogurt.
Dalmatian spots are also influenced by the Ticking and Flecking loci, which give rise to pigmented spots on a white background in animal coats. While this much was known about dalmatian spots, until the early 2000s, nobody was quite sure why some dalmatian spots are black on white while others are liver-colored.
A 2005 paper was able to trace the difference in Dalmatian spot color down to a single microsatellite marker, FH2319, found on chromosome 11 for these canines. They concluded that this type of TYRP1 genetic variation was likely responsible for the color variation seen in dalmatian spots.
Are dalmatians born with spots?
Dalmatians are almost always born without spots, instead covered in a coat of pure white fur. However, beneath that, the skin is often already pigmented with the black or liver color that will soon develop in the fur.
The color of the nose can sometimes be an early indication as to what color spots a dalmatian puppy is going to have, but the full aesthetic won’t be visible until the pups are around 10 to 14 days old. Once developed, the number of dalmatian spots normally won’t change, which makes them a handy identifier for prospective puppy parents.
Since the dalmatian spots are decided by the pigmentation of the skin from birth, these dogs don’t usually develop any further spots later in life, though sometimes smaller flecks can emerge. As animals with predominantly white fur and pale skin, sunburn is a risk factor – and since dogs can get skin cancer just like humans, any new and concerning spots later in life should be checked by a vet.
