Assessing age from colour of coats – A case study involving Thornicroft's giraffes

Here is an interesting piece of research done on giraffes. Prof Fred Bercovitch from the Primate Research Institute and Wildlife Research Centre, Kyoto University working in tandem with  local  naturalist Phil Berry have discovered that Male giraffes' age can be estimated by looking at the colour of their coats. The research was done on Thornicroft's giraffes found in eastern Zambia's South Luangwa Valley. It is one of the nine recognised sub-species of giraffe.

The researchers were able to attach specific ages to coat colour changes. Change in male pelage colouration takes on an average 1.8 years. The males are completely covered with coal-black blotches at an average age of 9.4 years.

Journal Reference 

Darkening coat colour reveals life history and life expectancy of male Thornicroft's giraffes

P. S. M. Berry and F. B. Bercovitch,

Journal of Zoology, Article first published online: 8 MAR 2012 DOI: 10.1111/j.1469-7998.2012.00904.x