Evolution is thoughtless, lazy and imperfect - and that is exactly why it works!
Evolution is thoughtless, lazy and imperfect - and that is exactly why it works!
Mangabeys
Old World Monkeys
Monkeys and apes are divided into all sorts of groups. Together with zoos I have studied demographic information of two mangabey species, which belong to the ‘Old World Monkeys'. I recently published a paper
about these relatively unknown and understudied species, together with my co-workers.
Demo - what, exactly?
Demography. That is the study of population changes, such as births, deaths and shifts in sex ratios. As it just so happens, this is exactly the type of information that zoos carefully keep track of with regards to their animals! In so-called ‘StudBooks’, which are a type of databases, this demography is recorded. Those StudBooks can be incredibly valuable in case we want to learn more about the biology of the animals: reason enough for me to work as an intern at GaiaZOO - a Dutch zoo - during my Master studies!
They resemble us pretty well!
During the study I was digging through the International StudBooks of the black-crested mangabey (Lophocebus aterrimus) and the grey-cheeked mangabey (L. albigena). I found out that the mangabeys are not that different from other primates, like ourselves, when it comes to their demography. For instance, the females generally become older than the males. Also, the longevity of the mother, as well as the age of the mother at the moment she gave birth to her offspring, seemed to partially predict what the longevity of the young would be.
Monkeys out of the bag
A somewhat unexpected monkey came out of the bag: the data suggested that there was a difference in how old mangabeys would get when they lived their lives in North American versus in European zoos. It remains to be discovered whether this is explained by genetic factors (“good” or “bad” genes), environmental factors (like husbandry, the climate, different diets, etc.), a combination of the two, or something else entirely.
To keep optimizing the welfare and longevity of all mangabeys in zoos worldwide, more research is obviously necessary. Luckily, zoos conduct a ton of research projects and they collaborate with universities, museums and countless other organizations! I will appear in a Naturalis video about this shortly, too - so stay tuned!
This study I performed with the University of Wageningen and I was an intern at the office of GaiaZOO in Limburg.