Homo luzonensis team pursue tests to place dwarf species in human family tree

Kristine Sabillo, ABS-CBN News

Posted at Feb 05 2020 04:59 PM

Skulls are placed as representative of present-day and latest discovered fossils from Asia as Archeologist, Professor Armand Mijares explains bones of the Homo-Luzonesis at the University of the Philippines (UP) Science Auditorium on April 11, 2019. Jonathan Cellona, ABS-CBN News

MANILA — The team that discovered the world’s newest ancient human species will be returning to Cagayan province this month in search of more fossilized remains as part of efforts to find out how Homo luzonensis fits in the human family tree.

“Next week we’re starting excavation to get more fossils. If we get a nice mandible or skull cap, then we can reconstruct it,” Dr. Armand Mijares, the Filipino archaeologist who spearheaded the project, told ABS-CBN News at the sidelines of the International Homo luzonensis Conference in Quezon City this week.

Mijares and other international experts will be excavating in Callao Cave in Cagayan from February 10 to March 22, a project funded by the National Geographic. 

Dr. Florent Detroit, who was the lead author in the paper that proved the Callao Cave remains were from a new species, said finding new fossils would be an important step. 

“And also (we might find) additional animal bones, which may be related to the behavior of Homo luzonensis,” he said, adding that they would also want to find stone tools.

Since the publication of their paper last year, Mijares and Detroit’s findings have made headlines around the world, stirring much interest in the Philippines and the possibility of finding other species in other islands.

After finding enough fossils to prove that it is a new species, Mijares and the team will now be trying to find out the lineage of Homo luzonensis, which is believed to have lived in the Philippines 50,000 years ago.


FAMILY TREE

Mijares said they are hoping to work with molecular anthropologist Frido Welker, who also presented a paper at the conference on Tuesday.

“He does protein. We can’t get DNA from tropical fossils. They don’t survive well. But apparently they survive better as protein in enamels. So we’re working with that,” Mijares said.

During his talk, Welker explained how it is possible to extract protein from fossil remains in warm climates like the Philippines. Sequencing of proteins will allow scientists to identify the source of a bone and even determine its gender.

Mijares said such laboratory tests will be a better basis of lineage than morphology or simply comparing Homo luzonensis’ bones to that of other species. Mijares has described the new species’ features as “mosaic,” with some bones looking like something from the family of Australopithecus or the Homo erectus. 

“The (next scientific) paper is to introduce to the crowd the new method (of palaeoproteomics). It’s a new method that they applied in the Denisovan (another ancient human species) in Europe,” Mijares said.

Detroit said there are two possibilities on the lineage of the Homo luzonensis, which is described to be a “dwarf” species like the 3-foot-7-inch Homo floresiensis found in Indonesia in 2003.

“They (Homo luzonensis) could be directly (related to) very primitive hominins such as Australopithecus or Homo habilis but we don’t know them (to have reached) Asia so that would be big surprise,” Detroit said. 

The second hypothesis is that they descended from the Homo erectus, an ancient human species, whose remains have been found all over the world. 

At the conference held at the University of the Philippines on Monday. and Tuesday, experts who have collaborated with Mijares and Detroit shared their own studies on ancient human species in Asia, adding as well their own questions for the Homo luzonensis team. Among these are how the Homo luzonensis reached Luzon and whether they used stone tools.

Mijares said the main goal of the conference was to see Homo luzonensis’ impact on the general view of evolution.

“At the end of the conference we hope to see possible collaborations,” Mijares said.

Other speakers at the 2nd day of the conference included anthropologist Susan Hayes who does facial reconstruction of ancient species, Dr. Deborah Argue who did an extensive study on the origins of the Homo floresiensis, Dr. Yousuke Kaifu who has done experiments on how ancient people traveled by sea in East Asia, and Dr. Peter Bellwood who has written more than a dozen books on archaeology in Southeast Asia.

Detroit said the conference was a great opportunity to get feedback from experts in other fields of science. He said the discovery of the Homo luzonensis even sparked a lot of attention in his home country France.

“It’s (Philippines’) far from France but people are very very interested. I gave many public conferences,” he said.

Mijares himself gave around 30 talks in the Philippines and abroad.

He said the discovery of the Homo luzonensis also opened doors for other Philippine researchers.

“There’s a lot of possibilities. Even for my students, when they apply for short grants with National Geographic, they can most likely get it now than before,” he said.

Detroit said he hopes the attention will help “develop further the teaching programs and the research, the laboratories, the equipment” that Filipino researchers need. 

UP senior lecturer Andrea Cosalan said the discovery of the Homo luzonensis and the 700,000-year-old rhinoceros has allowed the general public to learn about archaeology. 

“The discovery in itself and all the publications provided a lot of publicity and people realized the relevance of that. Therefore you would also get an influx of funding, grants,” she said, adding that students now realize that they have much to discover and work with.