Amazing stuff!
"Over the past 2.5 million years, sea levels have waxed and waned around the islands of Southeast Asia, sometimes exposing a sunken landmass—now called Sundaland—and letting animals migrate from mainland Asia onto islands like Borneo and Java. Now, in a series of four papers, researchers have described the first hominin to be uncovered from this now-sunken landscape, as well as other vertebrate remains.
The new discoveries piggyback off of a construction megaproject. In 2014 and 2015, an Indonesian port company dredged about 5 million cubic meters of sand from the sea floor off Java’s northern coast to build an artificial island. Geologist Harold Berghuis, a consultant with the dredging company, suspected the area might contain important fossils. So, he asked the port authorities whether he could survey newly made island.
When he did, fossils were everywhere. In all, Berghuis collected more than 6300 fossils from dozens of vertebrate species—including ancient humans, sharks, rays, panthers, turtles, rhinos, elephants, and Komodo dragons—that are probably between 131,000 and 146,000 years old. To study the fossils, Berghuis decided to go back to school, switching careers from port consultant to paleontologist.
The fossils shed light on how hominins first moved into what is now Indonesia. Close analysis of two Sundaland skull fragments revealed a strong resemblance to H. erectus skulls previously found on Java. We even have an inkling of what these humans ate. Some of the bones bear marks consistent with butchery, including going after bovids’ tongues, and the breaking open of bones to collect marrow—some of the first evidence of its kind found in Southeast Asia."
From the abstract:
"Eastern Asia yielded a rich fossil record of Pleistocene hominins, ranging from Homo erectus and the diminutive island species Homo floresiensis and Homo luzonensis, to post-erectus grade late archaic Homo (including Denisovans), and finally to anatomically modern humans.
The Sunda Shelf played an important role in the dispersal and evolution of hominin populations. The shelf has been widely exposed during most of the Pleistocene, forming a landmass known as Sundaland.
Today, the area holds the world’s largest shelf sea. Thus far, hominin fossils from submerged Sundaland were not available.
Here we report on the finding of two hominin cranial fragments from the submerged Sunda Shelf, retrieved during a dredging work in the Madura Strait, off the Java coast. The specimens derive from the sandy fill of a late Middle Pleistocene submerged valley of the Solo River and consist of a frontal fragment and a parietal fragment.
Metric and morphological comparisons with Pleistocene skulls from the Asian mainland, Java and Flores point to a relation with the late Homo erectus of Java, in particular with the crania from Sambungmacan.
The Madura Strait hominins were probably part of an MIS6 population that lived along the Solo, which in this period continued eastward over the exposed shelf area of the Madura Strait. Probably, the large perennial rivers of Sundaland offered good living conditions for Homo erectus, in a late Middle Pleistocene climate setting that was relatively dry."
Ancient human ancestor emerges from sunken Southeast Asian landmass (behind paywall)
The late Middle Pleistocene Homo erectus of the Madura Strait, first hominin fossils from submerged Sundaland (open access)
Fig. 1. A: The Sunda Shelf of Southeast Asia, with the Indonesian archipelago. Box indicates the position of map B.
B: Eastern Java, the Madura Strait, the Solo River, Ngandong, Sambungmacan, and other hominin sites. ...
C: The Madura Strait north of Surabaya, with the sand extraction area and the location of the BMS land-reclamation.
Fig. 4. Madura Strait 1 (MS1): Homo erectus frontal fragment with dextral supraorbital torus.
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