Week 3: Data collection at the PRI

Hello again, and thank you for continuing this adventure with me! I’ve had a busy week of data collection here in Inuyama, Japan. I was fortunate last week to have had access to a great variety of primate skeletons housed at the Primate Research Institute (PRI), and also to continue data collection this week at the Japan Monkey Centre (JMC). 


As I explained last week, I’m studying the evolution of the unique forelimb pattern shared by both Ateles (a New World monkey) and Colobus (an Old World monkey). In order to understand the relationship between Hox gene expression and limb growth, I’m looking for correlations in size between the different limb elements, in particular between the fingers and distal forearm.  To do this, I spent the week measuring the radius, ulna, and metacarpals.


Although the focus of my research is on Ateles and Colobus, it’s always helpful to measure a variety of primate species for comparison.  This week I’ve measured primates as large as orangutans and as small as a squirrel monkey (often smaller than 2lbs during life). And everything in between! Because I’m measuring many kinds of primates that span a wide range of body sizes, I take extra measures to normalize my data, or correct for these drastic differences in size.  Therefore, I also measured aspects of the humerus, as well as weighed a couple of small bones that, in part, comprise the wrist.  


Due to the typical nature of skeletal collections, and depending on the size of the primate I’m working with, it’s often difficult to piece together the teeny, tiny bones that make up the hand and wrist. It’s like a very small 3-dimensional puzzle. Sometimes the work is slow, but, of course, it’s always very rewarding once I complete it.


This is all deeply intriguing and exciting, but I have to say: nothing compares to watching and listening to the chimpanzees in the four-level, specially constructed, wide-open enclosure just outside the PRI! Join me next week as I wrap up my data collection and travel back to Kyoto.




This research is supported by the Japan Society for the Promotion of Science