The race against the sun to reach Issa Valley and the GMERC site ended in a draw between the last of the dying rays of light and our arrival at the turnoff that would take us to the camp. As dark settled in and the relative-ease of the brick-red dirt road now a distant memory, the beams of light broadcast from our trucks lit the way as we crawled for three-miles on the off-road drive. Our course followed a sandy double track that twisted over scrabbly rock outcrops, around sharp corners framed by slender yet towering trees, and steadily downward into the depths of the wild. The jostling, the bumps, and the bouncing reached their crescendo as we crossed over rutted channels carved through solid rock by a natural spring. And with that, the final turns brought faint camp lights into view. We made it, finally.

In a flurry of action, lit by the solum glow of several distant LED lights and the blinding beams of headlamps, we danced between the giving of greetings and the unloading of bags and supplies from the trucks. Our Field Course team intermingled with GMERC camp staff, the field assistants, and several resident researchers who were on hand to meet us. Amid the bustle, the Field Course students stood wide-eyed, their faces displaying shadowy moments of bewildered wonder. In this limited light, they could see only fragments of the impressive camp, an oasis of safety and civilization in a wilderness shared with all manner of unseen creatures and dangers. They would not get to see their new home in full until morning, but for now they were shown their tents and nearest bathrooms, given their field work assignments for the next day, and dismissed for bed. Thus, they entered their first night’s sleep in Issa Valley.

For our students, now veterans of a Tanzanian safari and adventures with the Hadza foragers, it seemed there was little left that could surprise. But the beauty of the Field Course is that just when one thought they had seen and done it all, it contrived a way to push them further out of their element and into new environments with new academic, mental, and physical challenges. And it did so at one of the most unique and productive primate research sites in the world.

Credit for the development of GMERC belongs to Fiona and Alex, whose PhD research inspired the founding of the site. Their vision, leadership, and dedication to the land, the animals, and the people of the GMERC team has transformed it into a major research location. Here, experts and students from universities around the world pursue projects that test hypotheses and generate data on the lives of the chimpanzees and red-tailed monkeys in a marginal habitat, as well as illuminate pieces of the human story. Even film crews have come to here to capture it all on camera for documentaries.

The GMERC camp has evolved tremendously since the first Anthropogeny Field Course visited in 2011. Back then, it was simple camp with two small structures and a few tents set on the ground. Now, there are semi-permanent structures with brick foundations that house the central eating, meeting, and kitchen areas, as well as the storage buildings, and lab and research spaces. The accommodations, still tents, are now on raised platforms and protected by wooden structures and thatched roofs. Two large solar arrays provide the entire camp with sufficient electricity to run all of the necessary tools, computers, and lighting, servicing all buildings and accommodation structures. Wells provide fresh water to handwashing stations, to the kitchen, and to filters for drinking. The bathrooms, while pit-latrine style, are solid structures with built in porcelain squatting-style toilets. If one had to “rough it” for six months or a year, this is surely the way to do it.

What sets Issa Valley/GMERC apart from places like Gombe or Mahale is its location and environment. Issa Valley is the easternmost region where chimpanzees can still survive. And they do so in a landscape utterly unlike the lush, dense jungles typically associated with their species. Issa Valley is actually numerous, steep valleys at significant altitude with miombo woodland up top and riparian forests below. Miombo is a dry mosaic of grass and woodland dominated by Brachystegia trees. The tall Brachystegia are widely spaced, allowing grasses to thrive beneath them. Fire is a frequent but vital part of the miombo’s life cycle. In contrast, the riparian forests that line the streams and waterways of Issa's many valley floors form narrow, ribbon-like sanctuaries. Their green canopies and cool but dense understories provided refuge for countless species, as well as prime sources of fruiting trees. Unlike the miombo above, the riparian forests are packed with thick foliage and creeping liana vines that make travel difficult, but offer much in the way of food.

For the chimpanzees (Pan troglodytes) of Issa Valley, survival demands adaptability. They rely on the small riparian forests, knowing precisely when and where certain fruits and foods are available. They risk the relative safety of the thick forests and must traverse out of them and across the miombo in search of resources. It is very much a life on the edge of the very limits for these chimpanzees.

For the red-tailed monkeys (Cercopithecus ascanius) that reside at Issa Valley, the riverine and woodland habitats provide abundant opportunities to forage for fruits, flowers, young leaves, and insects, including insect galls on the underside of leaves. They travel in cohesive groups, using their agility to leap from tree-to-tree, rarely having to touch the ground. Highly social and ever alert, they add a constant backdrop of chirps, alarm calls, and rustling of leaves, a lively contrast to the slower, more deliberate movements of the chimpanzees. The monkeys also make for an occasional meal for the chimpanzees if paths cross and hunting opportunity is presented.

Additionally, the Issa landscape also resembles the reconstructed environment that supported Ardipithecus almost 2000 miles to the north (we observed the 4.2 mya fossils of Ardipithecus, known as "Ardi," at the National Museum in Ethiopia). This makes Issa Valley a living laboratory where researchers can explore questions about bipedality, comparing Ardi, humans, and chimpanzees. The research at Issa has revealed that the chimpanzees here use bipedal movement in trees more frequently than those at any other site. Because of the demands of the miombo and riparian environments, they have adapted their locomotion while in trees, quite possibly in a similar response that drove Ardi to be an arboreal biped. It should be noted that this form of chimpanzee bipedalism involves overhead brachiation, with forelimbs used for balance and stability while moving through the canopy. On the ground, they return to their classic quadrupedal knuckle-walk.

From perspective of an obligate biped, there are clear advantages and serious tradeoffs to walking on two legs in this diverse environment. Humans enjoy speed and efficiency across open, flat grasslands and clear paths, but struggle painfully through the dense undergrowth of the riparian forest, as well as climbing up and descending down the steep valley walls. Following chimpanzees in these situations is a losing proposition. Only their pauses to feed or groom allowed us to catch up and catch our breath.

The first morning at GMERC brought the students into the precise rhythms of the camp and provided their first full view of the site and surrounding landscape. GMERC operates on consistency. Breakfast of tea, coffee, beans, rice, fruit, and hardboiled eggs is ready by 4:30 AM, members of the morning teams trickle in and out to eat and warm by the fire starting at 5:00 AM. They assemble at the changing station at the fringe of camp to don their field clothes, disinfect hands and footwear, and begin their silent march into the pre-dawn dark by 6:00 AM. Those on afternoon teams can enjoy a relaxed morning at camp before they too trek into the wilderness to relieve the morning team by 1:00 PM. Once handed off, the morning team makes the long, hard hike back to camp, arriving by 2:00 PM. Once at camp, they clean up, eat, download data, discuss findings, work on research projects, and perform camp maintenance. Dinner, similar in content as breakfast, is ready by 5:30 PM. The afternoon teams must stay with their subjects, as best they can, until they are nested before they can return to camp, typically returning by 8:00 PM. Rinse and repeat.

Regardless of the team, the goal and the operation is the same: find and stay with the subjects, observe and record behaviors, collect samples of feces and urine, and photograph and video when possible. Those on the morning team must be in place before dawn at the location of last contact, while the afternoon team must stay with the animals until they nest at night. The data collected depends on the project but typically involves "5-minute focals" in which behavior is recorded every 5 minutes. The GMERC teams use iPhones to enter coded data for each focal, which are then translated and assembled into meaningful conglomerations of analyses and figures. Ultimately, this data is published in scientific papers. Not all activity is primate-focused as there are numerous land and botanical surveys to complete, varieties of ongoing and new research projects, and camera traps to maintain.

So, this was our introduction to real primate field research and camp life. Over the course of our five days at the GMERC site, the Field Course students had multiple opportunities each to conduct observations and data entry of both chimpanzees and red-tailed monkeys, as well as to participate in botanical surveys to record the diversity of plant species of the area. These opportunities were precious as they not only received an unfiltered experience, they got to do all of these tasks alongside the researchers and field assistants who do this day in and day out.

The students discovered the work of primatology is tedious, tiring, unforgiving, and monotonous. The commute to and fro is long and grueling. Mental and physical limits are tested daily. You will rage at the unrelenting vines that conspire to grip you in their clutches. You will drift off in reveries, longing to socialize as you observe your subjects eating, playing, reproducing, squabbling, grooming, and sleeping. You learn real fast if you are cut out for field primatology and the sad truth is that most people are not. But the payoff for those who experience this work is profound: they are the rare few who get to see these amazing animals in full display in their natural environments. Second to this is most certainly taking a sunlit bath in the deliciously cool water of the stream near camp, with mesmerizing butterflies flittering about the flowers and foliage. What a world!

The final morning at Issa Valley arrived with a mix of relief and sadness. Relief came from knowing the long, grueling hikes and daily battles with vines were behind us. Sadness pervaded us all as we realized this marked the beginning of the end of our extraordinary adventure together. No laboratory, classroom, or textbook could ever replicate the rich experiences, lessons, and transformations provided by the Field Course. They certainly can't capture the majestic beauty of the many different landscapes we encountered or the vibrant diversity of peoples we met.

To commemorate our time here, we set out before dawn for one last hike to a nearby overlook that offered sweeping, 360-degree views of the interwoven valley system that makes up Issa Valley. There, in the cool stillness of early morning, we found ourselves high above all and in silence, letting the landscape speak for itself. We let the land imprint itself upon us one final time as the sun rose in pink and orange and a gentle breeze brushed over us. Each of us began the quiet work of processing everything we had seen, learned, and felt. All too soon it was time to return to camp where we said our goodbyes to the new friends we made there.