Dr. Alfred F. Pawlik led the exploration of southern Mindoro, the closest to Huxley’s Line, through the Mindoro Archaeology Project, which has surveyed limestone formations since 2010.

The project has studied more than 40 caves and rockshelters across Mindoro, Ilin Island and Ambulong Island.

“It’s a really large area of caustic formations, which means lots of caves, lots of potential to find archaeological sites and materials,” Dr. Pawlik said.

Among the sites excavated, Bubog 1, a rock shelter on Ilin Island, became the main site, yielding rich cave archaeology and significant findings from early humans in Mindoro.

“Those treasure hunters’ diggings were quite bad, but on the other hand, they told us right away that this site has a lot of potential because they exposed very dense, extensive and expanded shell midden; large deposits of marine shells that they obviously consumed in the past,” Pawlik added.

Beneath the site, terrestrial deposits revealed older artifacts, particularly fish bones that date back thousands of years.

“We have a series of radiocarbon dates for the shell midden only, not yet for deposits underneath, but the shell midden itself has a chronology of around 4,000 years ago near the top shell midden to as early as 35,000 years ago,” Dr. Pawlik pointed out.

Disturbed burials

At Bubog 2, similar shell midden deposits and shell artifacts were found, but excavation proved difficult due to rockfalls.

“In the end, we ended up using track cameras to dig through the drop fall. So by the time, just before the pandemic, [we] closed everything down. We are actually deciding to give up on Bubog 2 because it became too difficult to continue excavating” the Ateneo professor said.

Other sites investigated include Cansubong Cave on the northern coast of Ilin Island and Bilat Cave in Sta. Teresa, mainland Mindoro.

Findings in Cansubong Cave revealed disturbed burials and evidence of prehistoric occupation, while Bilat Cave provided records of shell midden deposits and human activity from the present to the Last Glacial Maximum.

“It shows that Mindoro was possibly [and] continuously populated [for the] last 40,000 years,” Dr. Pawlik said.

Pawlik’s research also uncovered early shell technologies used by ancient inhabitants.

Shell adzes made from giant clams were found in Bubog 1 and Bilat Cave, including a 7,000-year-old edge-ground Tridacna adze.

“Another one from Bilat Cave, almost the same age and then a bit older, an unfinished shell adzes but heavenly used, so they never bothered to complete the actual adze plate,” he added.

“Shell adzes are archaeologically and commonly associated with boat building,” Dr. Pawlik cited.

No evidence

Despite these findings, Pawlik noted the lack of direct evidence for early watercraft in the Philippines.

“But if you want to find out how they did that 50,000 years ago, how did those boats look like that they used for open sea fishing? We have, unfortunately, no material evidence,” he said.

“We don’t know much about maritime technology mostly because potential sites are underwater due to rising sea levels,” Dr. Pawlik argued.

However, available archaeological evidence suggests that Ilin Island was at certain times connected to mainland Mindoro, indicating fishing activity in both areas.

“The Southern Coast would prompt 700 meters sharply, which means fishing for them was always an option, and they have their boats there, and that [is] where they would go out and go start fishing, for example, 30,000 years ago, the Ateneo professor said.