Zambia study finds giraffe ageing clue
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A study of male Thornicroft's giraffes in Zambia has used records gathered over the previous 33 years by a local naturalist to confirm that a male giraffe's distinctive markings darken with the passage of time. The study's findings have been published in the Journal of Zoology.
The long-term nature of the study allowed the researchers to track the changes exactly over an extended period of time. In light of the finding that the males' coats began to darken at approximately 7-8 years of age and became black instead of brown approximately two years later at sexual maturity, the researchers have speculated that changes in testosterone levels due to puberty may be responsible.
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