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| Photo Credit: Reuters/Bruno Kelly
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The Palawa/Pakana community in Australia’s Tasmania has lived in the area for more than 40,000 years, when human ancestors first migrated to the region from Africa. This is also believed to be the earliest and farthest human migration from Africa and into the temperate latitudes of the Southern Hemisphere. A new study, published in Science Advances journal on November 12, 2024, analyses two historical records from the Bass Strait islands of the early humans’ interactions with their environments. This new study found evidence that ancient humans brought fire with them to the Lutruwitan peninsula and altered the forests there around 41,600 years ago.
Lutruwita was separated from the mainland Australia for most of the time period between 135,000 and 43,000 years ago, but the Palawa/Pakana communities were able to cross the Bassian Land Bridge (now Bass Strait, which separates Tasmania from mainland Australia) in this period when the sea levels were low.
For this study, researchers used two sedimentary records found each in Emerald Swamp on Three Hummock Island, and laymina paywuta, which according to the researchers is a local term for “a lagoon from a long time ago” on Clarke Island. Both these islands are situated on western and eastern extremes of the Bass Strait.
The study found that charcoal accumulation rates, which hints at burnt biomass and hence use of fire to alter vegetation in the area, increased abruptly around 41,600 years ago at the sites studied. A significant change in vegetation was observed around the 40,000 years ago mark.
There were also no major climate change events in southern Australia between 41,600-40,000 years ago, so increased charcoal influx, erosion-associated activities like more sediments, and transition from closed to open vegetation were possibly caused by humans with the use of fire. However, the study also points out that the environmental impact of extensive use of fire takes time to reflect in archaeological evidence, which is why they expect that ancient humans arrived in Lutruwita 41,600 years ago and the response of anthropogenic activities started showing in the area’s vegetation around 40,000 years ago. This is 2,000 years earlier than what archaeological records suggested for the southwest of the island.
From the Science pages
Flora and fauna
Published – November 20, 2024 02:26 pm IST
