Over the years I have camera-trapped a number of individuals of the species - Arctonyx Collaris - better known by its common name the Greater Hog Badger. 

They are a characterful species and I have been able to both video and photograph them at various locations in the Dong Phayayen-Khao Yai Forest Complex and the Kaeng Krachan Forest Complex at most elevations. They are not uncommon. 

As our incidences of photographing them has increased over the years we have noticed that the pelage color is somewhat variable in the animals we have photographed. This variation in colour, in our own images, does not seem geographically influenced as some of the individuals, even with strong pelage differences, have been photographed in very close proximity to each other.

In checking literature for notations of pelage variations I noted that such variations in Arctonyx are well documented, and not attributed to sexual dimorphism either, for example:

“Their fur color ranges from a dark grey to brown, while tail color ranges from white to a light yellow. Two dark stripes are found on the face, and the throat is white in color. The most notable feature is the "pig-like snout" that is used for feeding, along with modified teeth specifically used to move soil. Tail lengths range from 12 cm to 17 cm (120 mm to 170 mm). Another notable feature used to distinguish hog badgers from the closely related Eurasian badgers is the color of their claws. Hog badgers have light-colored claws whereas Eurasian badgers have dark claws. …… Also, there was little information on sexual dimorphism in hog badgers other than males are larger than females. “ ^{(Source: ”The Free Resource", 2012; Baker, 2012; Edmunds, 2003; Maslanka, et al., 2010)}

So what would drive such a variation in colouration? A little bit more digging around in the online literature flagged something very interesting. Badger's colouration is noted to be Aposematic.

Aposematic means a mechanism by which an animal advertises its dangerous nature to potential predators. Aposematic, or warning, mechanisms have evolved along with protective systems; it is advantageous for the protected organism not to risk the injury that is likely to occur in even a successfully repelled attack by a predator. Which in the case of the Greater Hog Badger means tigers and leopards and the warning probably refers to the badger’s aggressive temperament, and its sharp teeth and claws.

I found another interesting note on aposematism …. “The most common aposematic mechanism is the possession of bright or highly contrasting colours.”

But that got me thinking some more - why would pelage colour variation come into play in an aposematic species? What evolutionary principle was at play? I searched and searched and I will be frank - I did not find a reason.  I am totally unsure as to why the variations would exist. The only evolutionary principle that seems to be a strong possibility is sexual selection but as we saw above there is little information on sexual dimorphism and one would assume if it is a factor then it would be limited to males. One thing I am aware of from our pictures is that the badgers can suffer from an afflication that causes them to lose a lot of their body hair at times and it maybe some of the variations could be associated with pelage regrowth and by inflection then age could be a factor. After all pelage variations in a single species of mammal are not very common - I can only think of common adult variations in some local species of civet, but have seen variations in young, including bears in Thailand. The variables in the Finlayson's squirrel also sprang to mind but its now confirmed that all the morps are in fact sub-species. Perhaps we have some form of Leucism at play in the greyer example shown here which would leave the others as variations within a range of browns?

This is something that will now stick in my head and cause me sleepless nights I am sure, but its most enjoyable to ponder nature. So what do you think drives these colour variations?

Greater Hog Badger (Arctonyx Collaris) with dark brown colouring

Greater Hog Badger (Arctonyx Collaris) with brown/gold colouring

Greater Hog Badger (Arctonyx Collaris) with grey colouring (note shortness of pelage)

Greater Hog Badger (Arctonyx Collaris) with gold colouring

 Greater Hog Badger (Arctonyx Collaris) with pelage loss affliction

Paul Thompson