National Geographic Society

Photograph by Eduardo Rubiano Moncada
Spencer Wells on a city bus in Manila, Philippines.

Posted by Spencer Wells.

Just notched up my final trip of the year... 27 countries and dozens of places in the States.  This time it was the Philippines - my first visit, and a wonderful experience.  I'm exhausted from flight, but very pleased with the trip itself.  Incredibly geographically complex, with over 7,000 islands and 170 different languages, the Philippines sit at the apex of two key human migratory events. The first of these, the initial settlement of Southeast Asia more than 40,000 years ago, involved hunter-gatherers walking across now submerged land bridges connecting the islands of the Sunda Shelf. The second, dating to roughly 5,000 years ago, was the expansion of seafaring Austronesian-speaking peoples from present-day Taiwan. This latter migration would eventually turn east, heading out into the open Pacific with the extraordinary migrations of the Polynesians. These two ancient population movements, along with more recent migrations during the past few hundred years, have combined to generate the complex ethnic tapestry of the present-day Philippines.

Photograph by Eduardo Rubiano Moncada

Genographic outreach with the Ati community in Iloilo, Philippines.

After clearing regional consent protocols through Fudan University, I set out with my National Geographic colleague Jason Blue Smith into this fascinating genetic cauldron. We were about to visit members of the Aeta tribe, who live on the slopes of Mount Pinatubo on the main Philippine island of Luzon and who had previously worked with Dr Rand Allingham in 2006, a Genographic collaborator from Duke University. The Aeta have an atypical appearance for the geographic region where they live. Unlike most Filipinos, who share physical characteristics with other East Asians - straight black hair, an epicanthic fold over the eye, relatively light skin - the Aeta look more African. Early Spanish explorers referred to them as negritos - literally 'small, dark people' - and they do look more like pygmies from the Ituri Forest than the average Manila resident. Their unusual appearance has spawned many theories on where they came from, perhaps the most widely accepted being that they are the descendants of the pre-Austronesian population of Southeast Asia - the people who walked across Sundaland tens of thousands of years ago, then became isolated on islands as sea levels rose after the end of the last ice age.

The earlier trip with Dr. Rand Allingham yielded data from more than 100 Aeta, and the genetic results we have obtained are fascinating. We're currently writing them up, and don't want to discuss them in too much detail until they have been published, but the Aeta certainly seem to be a mix of both Austronesian and earlier genetic lineages, and their Y-chromosomes appear to be almost completely pre-Austronesian.

Photograph by Eduardo Rubiano Moncada
Genographic outreach in Iloio Philippines.

The trip we just returned from had two purposes: to return results to the Aeta community, and to work with another community on the island of Panay, about 300 miles southeast of Luzon - the Ati - thought to be related to the Aeta. The Ati outreach and sampling yielded 180 new samples to add to our analyses of genetic diversity in the Philippines. The most exciting part of the trip, though, was returning results to the Aeta. This involved a long drive from urban Manila into the lush, volcano-studded Pampanga region of central Luzon, where this Aeta community lives in a small village hacked from the jungle. We were unsure of what to expect when we drove in to share the Genographic maps and the genetic data.

The group assembled around us, jostling to get close enough to hear. I started off with a general description of DNA, reiterating and refreshing what the group had been told when they first shared their samples. The description itself was perhaps a bit dry, I thought, but when we got to the results that revealed that they trace their ancestry back to people who walked there from Africa tens of thousands of years ago, they got incredibly excited. The women in particular chattered amongst themselves, poring over the map and asking tons of questions about the details of the journey: how fast did they walk, did they ever use boats, what did they eat, and so on. One woman said that historically, most Filipinos had tended to view the Aeta as a 'primitive people', but that she now had more pride in her Aeta identity because "we were the first ones to come here, before the people with straight hair." She ended by taking me aside and asking me to tell other people about their results, to let them know that "just because we're small doesn't mean people should look down on us." It was a humbling experience.

Photograph by Eduardo Rubiano Moncada
In Nabuklod, Philippines, the Genographic team met with the Aeta community and elders to share their results.

It drove home a point that we shouldn't forget as we pore over the scientific data, worrying about the ages of genetic lineages or complex demographic details: that the results we obtain have special relevance for many participants, intertwined as they are with their own concepts of ethnicity, identity and land rights. The Aeta are a marginalized group of people that have little stake in the 21st-century Philippines. But genetically - and personally - they carry with them a fascinating tale of the first intrepid migrants to a new land tens of thousands of years ago. Small they may be, but they are genetic giants in the history of Southeast Asia.