Photo courtesy of Joanna Lambert
For many years, primates have mystified and intrigued uswith their similarities to humans. Movies such as “Planet of the Apes”sensationalize the idea of primates evolving with human-like intelligence.
While these primates may not work side-by-side withpeople, the way in which they interact with their environment can give usvaluable insight into anatomy, biology and ecology.
At UTSA, research done inside the classroom and out in thefield helps give a better understanding of our primate cousins. Dr. Joanna Lambert, a professor of anthropology, has made significant contributions tounderstanding how the biology of primate feeding affects evolution and ecology.
Named a fellow of the American Association for theAdvancement of Science, Lambert has devoted more than two decades of her lifeto research. Work done in the field of primate feeding biology has also beenuseful in their applications towards human anatomy and ecology.
“The kinds of questions I’m interested in are, how do thefeeding habits of these different primate species influence the forest andplant species they’re consuming,” says Lambert. Studying the intimaterelationship between primates and the plants they consume can offerunderstanding, not only of primates, but of the delicate rainforest they livein.
“What we’re realizing now is that, because we’re losingprimates from hunting, the forest isn’t regenerating.” Lambert explains that,from a conservation standpoint, understanding seed dispersal is vital tocomprehending the implications that primates have on their surroundings.
Lambert also studies aspects of primates relating to theevolution of their feeding habits. Events such as major climate shifts can haveprofound effects on animal and human eating habits.
“Looking at what happens in drought years, for example,what primates are doing differently and what food they fall back on has beenuseful for evaluating and answering questions about our own species,” she says
Working in the fields of Uganda has given Lambert afirst-hand understanding of how primates go about getting the food they need.“We all take it for granted that we can get the calories and nutrients we needin five minutes,” explains Lambert. “That’s extraordinarily different from anyother animal on the planet.
“Predators and competition from other animals can impacthow primates move in the forest and how they interact with other species.”
Being on site and living in the same habitat as theseprimates provides up-close opportunities for research that could not have beenexperienced in simply a classroom setting.
For 23 years, Lambert has been working at the KibaleNational Park, a high altitude rainforest in Uganda that borders the CongoBasin.
“When I first started going there, there wasn’t any sortof infrastructure and it didn’t have national park status; I basically stayedin a tent,” she says
“It’s amazing to do what I do but also not glamorous,”explains Lambert regarding her work in the rainforest. This sort of researchinvolves braving the elements and facing potentially dangerous situations.
Studying primates means “getting up really early in themorning when it’s pitch black and often pouring down rain, filling up abackpack with food and water and snakebite pack, getting raingear and headingoff into the forest where my study subjects will most likely be,” she says.
“I go through swamps, run from elephants, nearly step onsnakes. Last year, the rainy season never stopped and leeches would come intomy research house. For many years, there was no electricity and water, and Islept on a little cot with a mosquito net because there’s a lot of malaria inthe area.”
These research expeditions into Africa can be doneindividually or with a team. Lambert serves as the principle investigator andhas, on occasion, gone with graduate and PhD students to study primates.
When Lambert is not available to work at the field site,Ugandan field assistants, usually natives from surrounding villages, stay withthe animals to maintain their willingness to let people follow them.
Lambert describes her research methods and the fieldworkinvolved in studying primates. The Ugandan rainforest is utilized because ofthe species richness it provides and because it is home to abundance andvariety of primates.
“Because I’ve been working there for so long, there aregroups of primates that are habituated to the presence of humans,” explainsLambert. “This means we can get really good viewing conditions that allow us tosee what exactly these primates are putting in their mouths.”
While the primates living in the park have becomeaccustomed to the presence of humans, they are extremely vulnerable to viruseshumans may carry such as the common cold. Researchers maintain their distanceand never physically interact with their subjects.
One of the most interesting discoveries that can be madefrom studying a primate’s eating habits involves gaining a better understandingof human dietary habits. Debate has arisen on what is the most beneficial tothe human body. These arguments center on whether a meat or plant based diet isthe biologically sound way to fuel the body.
For primates, a vast majority of their calories comes fromplants; however, chimps occasionally hunt, even eating other primates.
Lambert explains, “Even in those populations, it nevermakes up more than five to 12 percent of their total annual diet. If you lookat our gut and our teeth, we have evolved to consume plants; but, having saidthat, at some point in recent evolutionary history, hunting and consuming meatbecame important to humans.”
Lambert elaborates by explaining that consuming cookedmeat allowed early humans access to energy that they might not have hadotherwise. This access was important to fuelling the human brain, which isenergetically expensive.
“We have the adaptations of a plant eater,” says Lambert,“but things shifted about a million years ago when eating cooked meat becameimportant in our evolutionary history, which fueled the evolution of ourbrain.”
The debate over whether humans should eat meat has manysides and cannot be easily settled. “I can say that our gut is the gut of avegetarian, but at the same time, we have an extraordinary amount offlexibility.”
Lambert explains that while primate digestive systems arenot directly comparable to humans, understanding what they eat can give us acomparative understanding.
“We know that eating a mostly plant-based diet makessense,” Lambert says of human eating habits. However consuming enough protein,whatever the source, is also essential.
More important than eliminating meat from one’s diet isunderstanding the detrimental effects that preservatives and synthesized fatshave on the human body.
“There’s a disjuncture between what we’re eating and whatwe were evolved to eat,” explains Lambert. Modern eating habits have led to theepidemic of diabetes and obesity that many Americans face today.
“Primates that consume this sort of diet are very ill.”
Currently, work is being done with primates in captivitythat analyzes the effects this diet has on their health. The South TexasPrimate Research Center has found that primates subjected to these conditionsbecome very unhealthy, gain wait easily and show signs of adverse healtheffects as indicated by the blood.
Primates and their eating habits can offer a clearreflection on our own eating habits; however, feeding habits can also bestudied for the effects they have on the environment.
Lambert explains that regions where these primates andother animals have been over-hunted have seen significant structural shifts.Primates help maintain a natural balance to their environment and are essentialto seed dispersal.
“It’s increasingly common to go into a forest but with noanimals in it,” says Lambert.
“It’s like an empty church. The structure of these plantsare the
re, but the animals are gone.”
Loss of primates has cascading effects. These regions haveplants that are adapted to having the pulp of their fruit eaten by primates andrely on primates to disperse their seeds. Without primates, the forests cannotregenerate; the extent of their loss is still not entirely known.
“People that study primates spend a lot of time thinkingabout these issues and coming up with solutions,” explains Lambert.
With upwards of two thirds of all primates labeled asendangered, it is imperative that national parks be created and loss of habitatlimited.
With the insight that primates allow into something asintimate as the human body or as widespread as the world’s ecosystems, it iseasy to see why many conservationists are concerned.
Currently, Lambert is writing a book that synthesizes morethan 20 years of data she has collected in the field. She plans to continue herresearch at the Kibale National Park studying primates and their feedinghabits.