The day started off relatively normal. GN’s male and female vocalized, as usual, towards GE, and then advanced across the fence of Yvaga Guazu. This has become the typical morning routine. Wake up…talk a little bit with the neighbors…maybe eat a Lauraceae fruit or two…then head off to where Leanna can’t follow. So they lost me right around 7:30 AM. Only 15 minutes later, my male, female, and juvenile all came back into Yvaga Guazu and moved towards one of their favorite resting trees (dubbed Lazy Tree #1). Seemed a little soon to be back in the park, but these monkeys are always throwing me for a loop. At 7:55, only ten minutes after arriving back within view, a strange monkey approached the group. Now, we’ve encountered strange monkeys before, but we have NEVER encountered strange monkeys here. All the other titis tend to stay towards the back of the park in the more forested area (minus GE), whereas this individual approached from the exact opposite direction. At first, my female merely arched her back, but then she chased the strange monkey at full speed to a tree about 50 m away, with the male and juvenile following close behind. By the time I got to this new tree, all four monkeys (male, female, juvenile, plus the stranger) were all sitting in close proximity and showing no aggressive behavior. Weird. Since just like ten seconds ago I was witnessing the titi equivalent to a high-speed chase. I’ve honestly never seen my monkey family run so fast. About a minute or so later, the group of four made their way back towards Lazy Tree #1 to rest. At 8:10 AM, all four were tail twined. It was at this point that I realized this strange monkey had to be one of GN’s subadults. Why else would the group dynamic change so quickly? There’s no way a total stranger would be accepted into a quadruple tail twine in such a short time period. So if this is one of my GN subadults (most likely the younger of the two older offspring, 3 year old Jasy), which I really believe it is, how/why was he on the other side of the fence? My normal family – male/female/juvenile – crosses that fence almost every day, and not once have I seen this other monkey nearby. The only times I have seen the two older brothers, I was in the back of GN territory, which is the complete other extreme to Lazy Tree #1. Also, why did the female react aggressively at first? Was she just caught off guard by the unexpected approach or did she not even recognize him?
Around 8:30 AM, all four were resting close, but nobody seemed very relaxed. You could cut that monkey tension with a knife. Occasionally the subadult would move away temporarily, and the juvenile would follow him. The juvenile would then spend the next few minutes going back and forth between the subadult and the male, as if he was unsure whom he was supposed to sit by or where he was supposed to go. It was during one of these momentary family separations that the juvenile, who was carrying the infant, moved towards the subadult and passed off GN’s newest addition to his older brother. Even further confirmation that this was, indeed, a member of the GN family. The subadult carried the infant for only a minute or so before bringing it back to the male. The notes from my field book accurately describe the situation as an “awkward family reunion.”
At 9:00 AM, completely out of the blue, my male and subadult began to fight. The male chased the subadult all throughout Lazy Tree #1 and then across the fence to a group of taller trees. The female followed closely, arching her back as the male and subadult battled it out relatively high in the canopy. The brawl was momentarily suspended when the subadult fell out of the tree FROM LIKE 15 METERS UP. Needless to say I was sure I had a monkey carcass on my hands. A brief, but triumphant Type 1 vocalization from the male and female, and then they made their way back to the lazy tree. The subadult followed. More fighting from the male and subadult – hitting, tail pulling, etc. – and a little more chasing, but each time the male tried to call it quits, the subadult would follow. After about 10 minutes, the whole group was back to resting. Just like that. The male, female, and juvenile all tail twined, with the subadult only 5 m away. An approach by the subadult, now touching the juvenile, but no aggression from either party.
9:20 AM. Ten whole minutes of hostile-free behavior. Subadult approached and initiated a quadruple tail twine. No big deal right? They totally did that earlier. Well this time the male was not having it….at all. Just seconds after the twine, the male once again chased the subadult across the road towards the taller trees, once again they fought, and once again the subadult followed the male back to Lazy Tree #1. The subadult then tried to fight the female, but the male intervened. Good for you! Defending your lady’s honor. Fighting, chasing, fighting, chasing, fighting, and then they were done. At 9:25 AM, the subadult slowly moved near the male and female, to within about 1 m of the duo. Then it got weird.
9:26 Subadult slowly laid down on the branch at the feet of the male/female
9:27 Subadult arched his back and squeaked at the male/female
9:28 Subadult slowly laid down, again right at the feet of the male/female
9:29 Subadult arched back
9:30 Subadult slowly laid down
9:31 Subadult arched back
9:32 Subadult slowly laid down
What is this? Is he showing aggression and then immediately performing submissive behavior? Whatever it was, it was repeated multiple times. The family then rested for another 20 minutes, with the subadult tail twined with the juvenile. Speaking of the juvenile, during each of these “instances,” he hightailed it out of there. Probably his best bet. Definitely don’t want to get in the middle of that family drama. It was also during this 9:20 encounter that my female injured one of her front feet. She spent the next half hour limping through the branches, struggling to keep close to her man.
As 10:13 AM rolled around, I witnessed a third chase scene from GN’s male and subadult, who again ran to the taller trees across the road. The female did not follow this time, most likely due to her wounded foot. The male returned, with the subadult behind at a reasonable distance. This seems to be a trend.
10:27 AM another male/subadult chase performance. This time, however, they remained in the lazy tree. Guess it’s not so lazy anymore. The female also got in on the action, fighting with the subadult. Hand-to-hand titi combat at its most intense. The female and subadult then fell off of their branch, momentarily catching themselves on a large limb, before falling the rest of the way to the ground. My male was freaking out. He immediately descended the tree, calling to the female, and waiting for a response. A few seconds later, the female and subadult came racing up a nearby tree, where the male took over chasing duty from the female. The male held the subadult in a monkey headlock for about 30 seconds before releasing him and returning to, and then tail twining with, the female. Another few repetitions of the subadult arched back/slow lay down routine, and then at 10:37 AM, the subadult approached the male and female and remained in close proximity.
A few minutes later, the juvenile returned. And all four rested, tail twined, and most likely napped for the rest of the morning. I mean seriously…these monkeys had to be exhausted. Their normal schedule calls for mid-morning naps even without multiple scuffles, so I imagine even after I left them around 12:30, they remained on that branch for a few more hours.
Moral of the story: not every prodigal son is welcomed with a fatted calf.
FUN SCIENCE FACT #18: The water bear (Tardigrade) can survive environments extreme enough to kill any other animal - with temperatures as low as -273°C (close to absolute zero) to as high as 151°C.