Saturday, July 22, 2006

Babies



On the same day as Alex's last beating, a new gorilla was born. The mother, Bebe (yes, that's her name), had been tested to see if she was pregnant, but the test came back negative. So the baby was something of a surprise. And this kid is ugly. We still can't tell the sex, but the infant was born about a month prematurely and is getting special medicine. Note the lack of hair and the lovely umbilical cord. Watching the mother and child it still quite cool. Bebe carries her baby around as if it were a doll, usually no head support so the infant's head hangs back with mouth open. You can see the little hands clinging to the mother's hair even this young.

The mother-child interactions are the most fun to watch. The kids just hang on while the mother moves around. The infants can walk early but are still very awkward with their limbs even after 2 years.


And at nap time, the kids find a comfortable place with mom. Despite some of the rougher realities of primate life, sights like these make these animals seem more like relatives.

Alex v Unyoro - round 2

Several days after Alex the chimp was attacked by the alpha male, Unyoro, the zoo keepers reunited the group. Several of us watched from the windows of the indoor enclosure where this occurred. We were all a bit nervous, as was Alex and his two step-sisters. Alex generally avoided Unyoro, as did Frahaga, the adult female injured in the last dispute. But by the end of the reintroduction experiment, no incidents had occurred.

The next day, things did not go so well. This episode was filmed, but the camera was shaking - the girl filming was terrified for Alex and had to hand off the camera at one point. Unyoro basically man-handled Alex, holding him down like he was prey and calmly biting his hands and feet and butt. Apparently, these are the most common areas to bite probably because they are the most tender. Periodically, Alex escapes and you hear the students yelling "Lauft Alex lauft" - Run Alex run. I'm not sure where the other chimps were during this attack but no one came to Alex's aid. Somehow, the zoo keepers managed to separate them after about 20 minutes.

I saw Alex in the nursery room later that day - this is a large room with one glass wall so you can see in. Alex had his arms wrapped around Alexandra, his cheek against her back, while she walked slowly with him. When Annette saw me she started swinging on a rope so that she could kick the glass where I was - obviously, they were protecting him from further harm. I went by later and saw one of the keepers cleaning the little guys wounds.

The word now is that there will be a third chimp group until the zoo can figure out a solution. Unyoro has been behaving badly to some of the other adult females making him a likely candidate for expulsion. No one wants to send an ape to another zoo because sometimes they get killed there - a similar version to what happened to Alex. But there may be hope. According to some recent zoo management studies, having one adolescent male in a group can lead to trouble - although usually the juvenile is the troublemaker. Having several juvenile males makes for a more peaceful environment - they keep each other in check. So sending Unyoro to another group where there are multiple young males might be an option.

In the meantime, Alex is walking around and recovering. We may think of this as a traumatic incident, but it is somewhat normal for a young chimp to suffer knocks and blows as he gets older.

Grateful orangs

One of the studies I've been following here is trying to find out if orangutans will display gratitude. The experiment requires training the orangs to trade one wood peg for one grape in order to establish a standard value - peg = grape. To do this, Katrin, the experimenter, scatters about 15 pegs on the floor of the ape cage before they enter. Once the subject arrives in the test cage, she sits at a Plexiglas window with two clear containers - one empty and one filled with 10 grapes. Katrin then requests pegs by holding out her hand. The orangs give them to her by sticking them through a hole in the window with their mouths. For each, peg they receive a grape until there are no more left. Then Katrin waits a minute to see if they try to trade more - by the end of training they should not because there are no more grapes to be had.

The orangs willingly exchange anything for food creating some interesting stories. At one point, Bimbo, the big dude, was being filmed by a TV crew who wanted to get a close-up. I'm not sure how they positioned the camera but Bimbo managed to grab it and get it into his cage. From there he broke it apart and traded the pieces for food.

The goal for the Gratitude study is to create an expectation of a fair exchange and to make clear that once the 10 grapes are gone, there is no point trying to trade more pegs. Once this pre-condition is established, the test phase will start with a normal one to one exchange, but then Katrin will give the subject 10 grapes for just one peg - an act of generosity. With no more grapes to acquire, the question is whether the ape will continue to give pegs as a sign of gratitude. There is more to this experiment in order to control the results to help interpret the behavior, but that is the basic idea. Interestingly, human children in a similar design showed no sign of gratitude. They accepted the windfall gain as if it were normal. A new version is under development.

From my perspective, these studies open the door to exploring fair exchange and a sense of value across species. For children, this is a developmental question; for apes, exchange is not a natural act, but the ability to learn this behavior quickly indicates the capacity for a "market sense."

Tuesday, July 18, 2006

Touched by a bonobo

Bonobos were "discovered" relatively recently in the history of primatology. Orginally, researchers thought they were small chimpanzees and named them pygmy chimps. After long observation and with genetic methods, these primates were identified as a unique species. They are different from chimpanzees in many ways - they live in a distinct area of the Congo, they are physically smaller and darker colored, and most notably, they like sex. They really like sex. Some researchers here think this particular facet of their behavior has been exagerated by the popular press, but bonobos generally engage in more frequent and diverse sex acts than other primates: male-female, male-male, female-female as well as many positions including the very human-like missionary position.

I've been watching the 5 (plus an infant) bonobos here hoping to see some hoka-hoka (the renowned female-female genito-genital rubbing - really, that's the technical term) but nothing too exciting has happened. The adults seem to play more than adult chimps and use burlap sacks to initiate play, but I haven't seen any sex at all.

And then came feeding time. Now, the chimps get all fired up about feeding, hooting and banging as they wait for the doors to open. The bonobos make a lot of noise too, but they also get excited in an entirely bonobo-like way. When the doors opened for these guys to enter the sleep room (where the evening feeding occurs), I had no trouble figuring out who the males were. All 3 males were fully erect and yelling and banging on everything. (I'll pass on a detailed morphological description, but let's just say that the relevant appendages are more plantain-like than human-like).

For this feeding, the zoo-keeper let me feed the apes directly, passing slices of melon, apple and bananas through the metal grid. My first handoff was to Joey, the largest male and a bit of a head-case. Joey spent a year in solitary confinement at another facility before coming to Pongoland and he developed a number of behavioral ticks as a result - twidling his thumbs and opening and closing his lips. This day, Joey was even more edgy because I was in the room, a new face. On my first attempt to pass food to him, my fingers got too close and he grabbed at them. I pulled away in time, but got a scratch that started to bleed. I cleaned it and sprayed with iodine (knowing what these guys do with their fingers) and was able to continue.

As the feeding continued, the erections died down and Joey settled into a Stevie Wonder head-swaying mode while twidling his fingers. The bonobos looked at me curiously, waiting for the keeper to open the doors between cages so they could all sleep together. As I observed them, the infant, Luiza, reached out through the bars and I shook her little hand.

Friday, July 14, 2006

Unspeakable things

My wife, Meighan, came to visit this past week and I took her to Pongoland to see the apes in action. We went to the observation deck where we watched the each species in turn but we eventually settled in with the chimps in the A group (the larger group without Alex and friends). Meighan took several pictures of the infants curled up with their mothers in nap mode. One of the male toddlers keep looking for a playmate but everyone else was more interested in sacking out. One little guy made a "nest" out of some burlap sacks creating a sleeping place - in the wild, chimps do this by pressing down giant leaves up in the trees. Frodo, an adult male, came over to the main napping area and lazily played with one of the toddlers, letting the guy walk on his chest.

All was peaceful and pleasant until one of the older females started doing something with her hand. We couldn't quite see what was happening until she moved a bit closer, walking awkwardly with several fingers deep in her ass. She found a spot to settle down and continued to explore her nether regions with great interest. None of the other chimps seemed to care, but Meighan and I eventually decided that we had seen enough for the day.

Gross behavior is an unfortunate part of working with animals. Even working with the little monkeys at the Hauser lab could be hazardous as the marmosets and tamarins routinely try to piss on visitors to their home rooms. Apes, however, take this to a new level. Yesterday morning during an orangutan experiment, one of the subjects entered the testing area with something in her mouth. You guessed it - a claylike wad of shit. Comically, the experiment required the orangs to exchange objects for food so naturally this was the first thing offered. Coprophagy, as it is euphemistically called, is common among zoo apes - I am not sure if this occurs as frequently in the wild. So next time you are in a zoo watching the apes and it is not feeding time, be prepared for what you might see.

Wednesday, July 12, 2006

Young Alex the brave

Alex has had a tough time since I've been here due to conflicts in his group. First, he loses half a finger in a mysterious fight with the B-Chimp alpha, Unyoro. This past week more trauma occurred with the big guy, but this time a student here witnessed the fight.

Remember that Alex was nursery raised along with two unrelated females, Alexandra and Annet, who are 7 years old, about 2 years older than Alex. Although they are unrelated, these three are very close.
Alexandra and Annet are in fact nearly inseparable - they walk with their arms around each other most of the time. These three kids were integrated into a new chimp group (B) over a year ago joining 3 adolescent females (~13 yrs old) and the alpha male. And things were going quite well until this month.

In the latest incident, Unyoro started to harass Alexandra, probably to copulate but maybe just to dominate her. Young Alex tried to intervene so Unyoro attacked him instead, biting his hands and feet (a common attack strategy). The little guy survived but is now back in the nursery while he recovers. Alexandra was also hurt so she and Annet were also removed from the B-group. Early this week, Unyoro attacked Jahaga, one of the adolescent females, sending her to the nursery as well. I'm not sure what is going on with this dude and what strategy the zookeepers will follow. To some extent this is just the way of chimp life.

Despite the emotional impact of these attacks on human observers, Alex's actions pose some interesting questions. Why play the hero when he knew the risks of getting in the way? If Alexandra were at risk of death, and Alex were her biological brother, his actions would make sense from a kin selection point of view - protect your extended genetic interests. They are not siblings but he still may view her as a sister having been raised with her. Alex may also have misunderstood Unyoro's intentions as life-threatening to Alexandra when in fact he was probably trying to rape her. This sounds horrible, but "forced copulations" are a normal part of chimp life. And if this was at the heart of the incident, Alex broke the rules by trying to intercede. Unyoro would have viewed his intervention as an attempt to monopolize the female and hence a challenge to his alpha status.

We can find a selfish motive for Alex's actions by adding a series of misunderstandings to the cognitive processes at work, but this is by no means a secure conclusion. Other apes form coalitions to protect "friends" or kin. Usually these are subordinate adults who join together to defend against a dominant's attacks. The female gorillas here, however, intervened on behalf of an unfamiliar female that the zookeepers were trying to integrate into Gorgo's harem. In a 20 min film recording the integration, Gorgo bit and threw around the new lady, Effi, tearing her flesh in several areas.
Two other females jumped on Gorgo to prevent further attacks even though they had nothing to gain but his ire. We could interpret their seemingly altruistic actions in non-empathic terms. Perhaps, they found the racket annoying and wanted it to stop. But after incurring some injury to themselves, repeated assists seem more likely to have empathic underpinnings.

Wednesday, July 05, 2006

False belief for chimps

One of the classic experiments in developmental psychology revealed a fundamental shift in social cognition that occurs around 4 years old. The Sally-Anne task was used to test whether children understood that another person could have a belief about the world that was untrue - a so-called false belief. The task was simple. The experimenter presents the child with two dolls, Sally and Anne. Sally and Anne decide to hide a piece of chocolate in a drawer (for example). Next Sally leaves the room and, while she is gone, Anne moves the chocolate hiding it under a pillow. The question for the child is: when Sally returns where will she look for the chocolate. The correct answer is the drawer, because Sally did not witness the change in location - in other words, she has a false belief about where the chocolate is. Young children, however, respond that she will look under pillow. They do not grasp that she can have a false belief.

Now, much work has been done on this topic modifying tasks to get younger children to give a correct answer. But the limit was pushed recently by a non-verbal task used with infants by Rene Baillergeon. The results are controversial and hence in need of replication. So of course, the researchers here tried a version on the chimps. Chimpanzees certainly understand certain kinds of mental content. They will look where you are looking, following your gaze behind barriers - a sign that they know you can see things they cannot. But full false belief is difficult to demonstrate non-verbally.

The study required training chimps to associate bananas with one color container (blue) and grapes with another (white). [This simple association took about 500 trials per chimp. Actions not part of their normal ecology are very difficult to learn.] The apes were shown the food first and then watched as the experimenter placed it in a yellow box. An occluder was raised while the experimenter placed the yellow box under the appropriate (overturned) container. The subject then gets to guess where the food is. So if the chimp is shown banana, he should point to the blue container to get the food.

Once the subjects have this down, a further step is added. After the experimenter hides the yellow box with the food (lets say banana again), she leaves the room. A different experimenter enters, exposes the yellow box and changes the contents to a grape, then places it under the banana container again. The first experimenter enters again and lets the chimp choose. Now, this is tough to follow but the ape needs to understand that although the food is now grape, the experimenter thinks it is banana and expects it to be where bananas usually go - the blue container. But the apes point to the grape container instead (white). I'm surprised they get this far given the task complexity.

Tuesday, July 04, 2006

Tea time for gorillas

Hoots and screams echoed through the tunnel system below the sleeping cages. They were getting louder, closer and soon the chimps would jump out of a trap door in the floor. I stood in front of the hole, heart pounding, realizing that I forgot to put in the ear plugs required when working with chimps. They came up quickly, one by one, some stopping to scream at me through the thick Plexiglass windows before moving to one of the sleeping cages to gather up their loot. Chimps are frugivores and they get a variety of sweet fruits for dinner - pineapple, tomatoes, apples, bananas, kiwis, etc. The zoo keepers scatter the food around the sleeping cages and the animals grab up handfuls before settling in to eat. Within a minute, the hoots disolved into quiet, messy munching.

Given that there is not much for a chimp to do at the zoo, they get very excited about food. There are several meals a day: breakfast, second breakfast (just like Hobbits), lunch, an afternoon snack, and dinner. They know the schedule and start making noise 5-10 min before the next meal - how do they know this? Not sure. I'll see more feedings this week and try to figure out if the other apes have this inner food clock. Maybe they just get hungry.

The gorillas are a different case. I didn't witness their arrival, only their peaceful munching. Gorillas are vegetarians and graze on leaves all day. For dinner they get lettuce, carrots, and other legumes. I can't fathom how a beast gets to be the size of Gorgo, the alpha male, on a vegetable diet. All of the gorillas are big, but he is particularly huge and frightening. I stood 2 feet away, not looking at his eyes, while his low guttural grunt shook the air around me. Dian Fossey was nuts.

The gorillas refuse to use the inside water dispensers so the zoo keepers had to come up with an innovative solution. It turns out that these guys like tea, mixed with yogurt - go figure. So each ape gets to drink the solution out of a gardener's watering pitcher. Gorgo sucks down several liters in a few seconds.

Thursday, June 29, 2006

It's hard out here for a chimp

Two days after I met Alex he got into a fight with Unyoro, the alpha male for the Chimp B group. The keepers found the little guy beaten up with one finger hanging off that they decided to remove. The researchers are puzzled because Alex is seldom as annoying as his sisters and not likely to challenge an older chimp at his age (5 yrs old). I saw him yesterday climbing one handed and staying out of the way of all the adults. He still carried his blanket with his foot.

Fights break out all the time among chimps for reasons not always evident to the novice observer. Juvenile males start to harrass adult females in order to assert their dominance. The alpha male eventually gets challenged by the young turks in the group. In the A group, Frodo periodically has attempted to assert his primacy only to be smacked down by Robert, the alpha, and Patrick, the third adult male who supports Robert. Alliances are more important than size, as described by Frans de Waal in Chimpanzee Politics.

The alpha male occasionally beats up one of the adult females, but females harass each other too. Swela joined the A group last year and has had a tough time integrating. The other females would beat her and chase her away. Eventually, she ingratiated herself to the adult males who now protect her from the other ladies. Swela does have the strange habit of making male-like sexual solicitations toward some of the females - she stamps her feet at them. But this has not gone any further.

Aggression usually takes the form of chasing, screaming, hitting with sticks or fists while the rest of the group hoots like crazy - basically, like the World Cup matches. But it seldom leads to the kind of damage that Alex suffered. When real problems between chimps develops, the care-takers can see it building over a few days and separate the troublemakers.