Present prehistories | The past
Questions surrounding human evolution and migration are a constant source of interest for archaeologists around the world. Three new studies, focusing on different times and places, offer new insight into the early spread and arrival of humans, from the first hominid footprints in Crete to the Pleistocene Homo sapiens in Indonesia, and signs of pre-contact human presence on the Falkland Islands (below).
Researchers studying a set of fossilized footprints on the Greek island of Crete have found they are over six million years old. The cluster of more than 50 footprints, believed to belong to an early hominin, was discovered near the village of Trachilos in western Crete (below) in 2017. Now new dating has revealed they were created 6.05 million years ago, vs0.350,000 years earlier than originally believed, potentially making this the oldest direct evidence of a human-like foot used for bipedal walking ever found.
The footprints (above) have several characteristics unique to humans, including the presence of a ball in the forefoot and a non-opposable big toe that rests on the end of the foot next to the other toes, while that other observable traits are also found in primates, such as a non-bulbous heel, a proportionally shorter sole, and the absence of a longitudinal median arch. Although researchers have acknowledged the need for caution as no body fossils have been found, and other archaeologists have expressed some skepticism, the team behind the latest work suggests that the creator of the footprints of Trachilos can be tentatively identified as a primitive bipedal hominin.
Regardless of their exact location in the phylogenetic tree, these tracks represent a source of information that could be crucial for our understanding of early hominin evolution. However, a precise age was necessary in order to better understand their meaning. Stratigraphic dating was done when the footprints were first reported in 2017, but the new research, recently published in Scientific reports, used paleomagnetic and micropaleontological methods to produce the date of 6.05 million years ago. This gives the footprints the same age as the fossils of Orrorin tugenensis from Kenya, which is the oldest known upright walking biped in Africa. It is possible that the Trachilos footprints were created by a species that developed alongside O tugenensis and that together they represent the earliest evidence of bipedal hominids.
Although uncertainty remains about the precise relationship between the creators of the Trachilos footprints and other early hominids, recent dating work opens up new avenues for future research.
Pleistocene people on Sulawesi
The island of Sulawesi has yielded much important information about early human activities in Indonesia, including the oldest piece of representative rock art in the world, dating back at least 45,500 years (see CWA 106), but the discovery of a human jaw fragment in Leang Bulu Bettue Cave in Southwest Sulawesi represents the earliest human skeletal remains from the Pleistocene period found on the island. Although modern humans are thought to have arrived in the area 70–50,000 years ago, there are currently only a few Late Pleistocene sites attributed to Homo sapiens in Indonesia, and fossil evidence of their presence. are also very rare.
The Leang Bulu Bettue fossil, which was found during excavations in 2017, has now been dated to between 24,800 and 16,000 years old using materials from the sediment layer it was found in, including isotopic analysis stalagmites, radiocarbon dating of shells, laser ablation of a pig’s tooth and optical dating of feldspar grains.
The right jawbone (below) is so fragmentary that archaeologists have been unable to uncover much about this individual beyond the fact that he was an adult and had fairly poor oral health. However, the surviving teeth show unusual tooth wear that may potentially be related to non-food use such as the production of twine from palm fronds. Despite its fragile nature, the find offers the first direct fossil insight into the earliness H sapiens on Sulawesi interacted with their environment at that time.
The fossil was found in a layer associated with material from domestic activities such as the production of stone artifacts and the preparation of food, as well as portable works of art and signs of pigment use which point out that this individual may have been part of the responsible population. for some of the oldest rock art in the world, suggesting that the artistic tradition of South Sulawesi existed from at least 45,500 years ago until the last glacial maximum (vs.23,000 years). No other evidence of human burial has yet been found in this layer, but the presence of the jawbone leads archaeologists to hope that other remains may be found in future excavations.
First visitors to the Falkland Islands?
When Charles Darwin visited the Falklands in 1833, he was intrigued by the presence of the islands’ only land mammal, the ‘warrah’ or Dusicyon australis. This wolf-like animal was driven to extinction by Europeans in 1876, but the question of how it reached the islands originally remains unanswered. The apparent lack of evidence of any pre-contact human activity on the islands originally led to the conclusion that it must have evolved from a continental South American species (Dusicyon avus) that crossed the South Atlantic during the last glacial maximum. However, new research lends credence to an alternative explanation – that the warrah diverged from Davus on the mainland and was brought to the islands by humans in the more recent past.
A new interdisciplinary study has identified several pieces of evidence that point to human presence on the islands prior to the arrival of Europeans in 1690. The first is a projectile point found on New Island in 1979 that is made of locally sourced stone and corresponds to lithic technology. used in Tierra del Fuego for the past 1000 years. Second, in 2018, investigations near the discovery point of the point identified seven deposits of disarticulated animal bones. The excavations of two of these deposits, dating between vs0.745 and 600 years ago determined that they appeared to be dump or secondary processing sites consisting primarily of sea lions and penguins, indicating that human hunting of these species occurred on the island between 1275 and 1420 AD.
Third, signs of ancient fires can be seen in the peaks of charcoal levels in the sediments. Analysis of peat core from New Island shows significant increases vs1,000 years ago and 620 to 470 years ago, while a previous peat record near Stanley also identified a notable increase from 5,470 to 3,570 years ago. Although fires can be caused by lightning as well as humans, such weather is very rare on the Falkland Islands. Moreover, the patterns of these peaks directly reflect the increases that have occurred vs250-190 years ago when Europeans first established settlements on the islands.
Finally, carbon and nitrogen isotope analysis of West Falkland warrah bones (above) indicate a marine diet heavily reliant on sea lion and penguin, which may indicate a commensal relationship with humans . The oldest warrah bone has been dated to at least vs.3,400 years ago; although this is considerably earlier than the fire and bonepile evidence from New Island, when considered with the other charcoal evidence from Stanley, it supports the suggestion that humans may also have visited the Falkland Islands at earlier times, possibly bringing war with them. It is hoped that future work will shed more light on this intriguing question.
U Kirscher, H El Atfy, A Gärtner et al (2021) ‘Age constraints for the Trachilos footprints from Crete’, Scientific Reports (https://doi.org/10.1038/s41598-021-98618-0).
A Brumm, D Bulbeck, B Hakim et al (2021) ‘Skeletal remains of a Pleistocene modern human (Homo sapiens) from Sulawesi’, PLoS ONE (https://doi.org/10.1371/journal.pone.0257273).
K M Hamley, J L Gill, K E Krasinski et al (2021) ‘Evidence of prehistoric human activity in the Falkland Islands’, Science Advances (https://doi.org/10.1126/sciadv.abh3803).