The Adventures of Uno and Wrinkle Belly (aka El Calvo)

This week I spent a lot more time with the monkeys, and I’m getting to know Uno, Wrinkle Belly (his Spanish name is El Calvo), and the others a bit better. Even though Simeon had previously assured me that there’s only one group in this patch of forest, we confirmed that there are in fact two groups. The North group is often found along the edge of an abandoned field and occasionally makes forays up Spondias Lane. Wrinkle Belly (or El Calvo, his Spanish name) is part of this group. The South group lives in the former coffee plantation and doesn’t appear to have as much access to Spondias fruit. Uno, his lady Pink, and Pink’s two kids are part of this group. I’m going to continue to follow both groups and hope that I can get adequate data on adult females/males and juveniles every month from each group. Plus, I am far to intrigued by the lives of Uno and Wrinkle Belly to choose one or the other’s group.

On Wednesday I followed Wrinkle Belly himself and found the whole experience to be quite hilarious. This old guy just doesn’t move around too well. The other monkeys will leap across a gap between trees while they are traveling, but poor old Wrinkle Belly sits there looking for a safer route. Oftentimes, he comes pretty close to the ground. Once while attempting to jump across a gap, he didn’t quite clear it and nearly landed on my head. Despite these apparent infirmities, he appears to be an active social member of the group. Much to my surprise, I saw him copulate with a female and then continue to (slowly) follow her around for most of the day. At another point, he was sitting next to male; all of a sudden, the two turned to each other, embraced, and then went back to resting.

On Thursday, Simeon came out with me to collect leaf samples. The whole process went quite well actually. We ended up with the South group this time while they were enjoying what I call “The Buffet.” This spot must be monkey heaven. Right here they have a giant Madero Negro tree (whose leaves they eat), and the tree is covered a Pica Mano vine (whose leaves and berries they eat). Next to the Madero Negro are Caimito and Coloradito trees—these leaves also make a fine meal. They ate all of these things on Thursday, and Simeon got me samples of each. The guy is amazing. He didn’t even use the special chain saw thing I bought for this purpose. He grinned and told me he would climb up the trees like a monkey—and he did. After we got the samples and said Hola to Wrinkle Belly on our way out of the forest, I came home and used the toughness tester for hours.

The toughness tester itself causes me a great amount of anxiety. Coming up with the idea that toughness may be a limiting factor in juvenile diet and therefore may have an impact on the howler life history strategy was no problem. Actually coming up with a machine to measure toughness was a whole nother story. I endured an endless amount of sleepless nights, anxiety attacks, throwing up, etc, in the whole process of coming up with a machine. Now that I have one, I barely know how to use it and I am paranoid that it is going to stop working again. While I was using it on Thursday and Friday, I had this sinking suspicion that something was very wrong. The values I was getting were completely crazy. I tested Madero Negro leaves and compared my numbers with some that had already been published. Not only were my own values wildly variable—they were also totally different from those in the article. I was freaking out. I emailed Barth—the colleague who briefly trained me to use this machine over one year ago—and his reply calmed me down a little bit. I continued toughness testing all day Friday. I still don’t know if there is a problem with the machine or my ability to use it, but I am going to keep trying and hope that with enough samples, my values begin to make sense. In the meantime, I am trying to come up with a different dissertation topic—just in case. If you have any ideas, please send them my way.