This 2013 video shows several Negrito groups, including the Ayta, in the Philippines.
"Researchers have known from several lines of evidence that the ancient hominins known as the Denisovans interbred with modern humans in the distant past. Now researchers reporting in the journal Current Biology on August 12 have discovered that the Philippine Negrito ethnic group known as the Ayta Magbukon have the highest level of Denisovan ancestry in the world. In fact, they carry considerably more Denisovan DNA than the Papuan Highlanders, who were previously known as the present-day population with the highest level of Denisovan ancestry." Source: Science Daily.
Note: Most of the interbreeding with Denisovans seems to have taken place on the Pacific islands. According to Wikipedia, "A 2011 study found that Denisovan DNA is prevalent in Australian Aborigines, Near Oceanians, Polynesians, Fijians, Eastern Indonesians and Mamanwans (from the Philippines); but not in East Asians, western Indonesians, Jahai people (from Malaysia) or Onge (from the Andaman Islands). This means that Denisovan introgression occurred within the Pacific region rather than on the Asian mainland, and that ancestors of the latter groups were not present in Southeast Asia at the time, which in turn means that eastern Asia was settled by modern humans in two distinct migrations."
I could be wrong about this, but I think the oldest edge-ground stone axes have all been found in Australia. According to this Survival & Self-Sufficiency article on how to make stone axes, "[e]dge-ground axes have been dated as early as 25,000 years ago in Arnhem Land, Australia, and 31,000 years ago in Cape York. This is the earliest known use of edge-ground axes anywhere in the world." However, it looks like an even older find, also in Australia, has been made since the article was written. In 2016, ABC Science reported the discovery of the world's oldest ground-edge hafted [handled] stone axe fragments in Western Australia:
"The discovery pushes back the technological advance [to edge-ground axes?] to between 45,000 to 49,000 years ago, and coincides with the arrival of people in Australia ... The fragment is 10,000 years older than the previous oldest known fragments found in northern Australia in 2010."
Note: The earliest stone-flake tools date back to at least two-million years ago. Acheulean hand axes are almost as old. I'm no expert on Stone Age tools, however, so I'm not sure what the difference is between the Acheulean axes and the axes found in Australia.
"Moa were nine species (in six genera) of now-extinct flightless birds endemic to New Zealand. The two largest species, Dinornis robustus and Dinornis novaezelandiae, reached about 3.6 m (12 ft) in height with neck outstretched, and weighed about 230 kg (510 lb) while the smallest, the bush moa, was around the size of a turkey. Estimates of the Moa population when Polynesians settled New Zealand circa 1300 [AD] vary between 58,000 and approximately 2.5 million." (Wikipedia)
The moa look terrifying, but they were plant-eaters and must have been a plentiful source of meat for the first Polynesians in New Zealand. Hunting these creatures would have been dangerous, though, at least to a certain extent, since their beaks were like pruning shears, according to Wikipedia, and the biggest varieties were heavy enough to cave in your chest or skull if they stepped on you.
"Pitcairn Island is a place so remote, and with a history so bizarre, that until recently it was viewed almost as myth rather than reality. But the events that took place on this tiny island in the Pacific Ocean were very real. Settled by a pack of mutineers of the HMS Bounty in 1790, along with a small group of Polynesians, the island soon became like the famous 1954 novel Lord of the Flies , in which a group of boys stuck on an uninhabited island descended into savagery and immorality. Faced with physical, social, and psychological isolation, along with struggles for power, the Pitcairn population rapidly diminished due to murder, suicide, and madness, and the remaining inhabitants descended into incest, sex abuse, and delinquency. Today, 47 inhabitants from just four families remain on this ill-fated island that carries with it a dark and evil history that has been retold in countless films and books." Source: Ancient Origins (2018).
Note: Pitcairn is one of four islands known collectively as the Pitcairn islands (Pitcairn, Henderson, Ducie and Oeno). They were uninhabited when they were discovered by Europeans, but they were originally settled by Polynesians who came to a bad end:
"The earliest known settlers of the Pitcairn Islands were Polynesians who appear to have lived on Pitcairn and Henderson, and on Mangareva Island 540 kilometres (340 mi) to the northwest, for several centuries. They traded goods and formed social ties among the three islands despite the long canoe voyages between them, which helped the small populations on each island survive despite their limited resources. Eventually, important natural resources were exhausted, inter-island trade broke down and a period of civil war began on Mangareva, causing the small human populations on Henderson and Pitcairn to be cut off and eventually to become extinct." (Wikipedia)
It's easy to romanticize these tropical islands, but at one point in time when the original Polynesian settlers still had operational trade networks, life on the Pitcairns must have been as close to paradise as it's possible to get on this Earth.
"Analysis of remains found on Rapa Nui, Chile (Easter Island) provides evidence contrary to the widely-held belief that the ancient civilization recklessly destroyed its environment [see below], according to new research co-conducted by faculty at Binghamton University, State University of New York." Source: Science Daily (2017).
Next video has some good views of Ahu Tepeu on Easter Island, another site used in this study, but the voice-over is inaudible.
Analyzing "human, faunal and botanical remains from the archaeological sites Anakena and Ahu Tepeu on Rapa Nui, dating from c. 1400 AD to the historic period, and modern reference material," the team determined that the Easter Islanders "had extensive knowledge of how to overcome poor soil fertility, improve environmental conditions, and create a sustainable food supply. These activities demonstrate considerable adaptation and resilience to environmental challenges -- a finding that is inconsistent with an 'ecocide' narrative."
The Easter Island ecocide theory.
Comment: According to the ecocide theory, the population on Easter Island collapsed because deforestation (1) led to the erosion of fertile soil which in turn led to starvation, warfare and cannibalism. If this new research is accurate, however, it would appear that the Easter Islanders had a plentiful marine food supply and a system for sustainable agriculture even after the loss of their trees.
(1)According to Wikipedia, "By that time [the arrival of the Dutch in 1722], 21 species of trees and all species of land birds became extinct through some combination of overharvesting/overhunting, rat predation, and climate change. The island was largely deforested, and it did not have any trees more than 3 metres (10 feet) tall. Loss of large trees meant that residents were no longer able to build seaworthy vessels, significantly diminishing their fishing abilities."
The pre-contact collapse of the Easter Island population is central to all of these different theories about what happened. According to the traditional story, their population declined from somewhere around 20,000 to the few thousand who were still living there when the Dutch arrived. Some believe that the islanders were decimated by diseases brought by the Europeans, which may have happened but doesn't explain the population loss before the European arrival. Others argue that "[t]he downfall of Easter Island may have had more to do with preexisting environmental conditions than degradation by humans." (Live Science (2015).
Just to complicate matters, it's possible that the population collapse never occurred at all. According to Ars Technica (2016), "new evidence from archaeological investigations has overturned a popular myth about the demise of the Rapa Nui civilization on the island. For centuries, observers believed that the Rapa Nui suffered a catastrophic population crash. But there is no scientific evidence to support this idea, say a group of researchers in the latest issue of the journal Antiquity. That story about environmental collapse and warfare you read about in Jared Diamond's bestseller Collapse? Totally wrong."
According to this new study, the people of Rapa Nui were better at managing their environment than previously believed, but as far as I can tell no one is disputing the fact that they deforested their island. Chopping down all their trees to build canoes and rollers for their giant stone heads (if that's what happened) doesn't seem to fit with the claim that they "had extensive knowledge of how to overcome poor soil fertility, improve environmental conditions, and create a sustainable food supply." On the other hand, it's probably unrealistic to expect that they had any knowledge of soil erosion and forest management.
I'm no expert on the history of Easter Island, but the "facts" about what happened seem to be all over the place. Did the population actually collapse? Who knows? The estimates I've found for the size of the original population range from 10,000 to 20,000 and I'm not sure what they're based on. If the population didn't collapse, then all these theories about why it collapsed are rendered instantly moot.
Life on Rapa Nui wasn't a peaceful utopia, at least during certain periods. That seems clear enough. The toppled stone heads are cited as evidence that warfare occurred at some point on the island, but the idea that the islanders destroyed themselves by warfare has been called into question and one source I've found even claims that they deliberately made sure their weapons were nonlethal. That seems kind of unlikely, but it doesn't really matter. One way or another, the real history is still obscure.
Easter Island is one of the most isolated islands in the world. It only covers about 64 square miles and even at its height (assuming the estimates are correct) it was home to only around 20,000 people. For all practical purposes, it was a closed system with limited resources. A culture like this would have been extremely vulnerable to climate changes such as low rainfall or anything that would effect fishing or the availability of other food sources. Periods of abundance would lead to population growth which would in turn put increased strain on available resources, leading to inevitable internecine conflict and population decline. Even under the best of circumstances, I would expect a population in this situation to stagnate and decline over time. Perhaps the question isn't why (or if) the culture on Easter Island collapsed, but how it managed to survive at all.
"Rock art of human figures created over thousands of years in Australia's Arnhem Land has been put through a transformative machine learning study to analyse style changes over the years. The study has tested different styles labelled 'Northern Running figures', 'Dynamic figures', 'Post Dynamic figures' and 'Simple figures with Boomerangs' to understand how these styles relate to one another." Source: Science Daily.
Video from 2017.
This was an interesting study because machine learning can be used to establish a chronology for different types of rock art. In this case the results were surprisingly accurate, confirming earlier work carried out by archaeologists:
"One amazing outcome is that the machine learning approach ordered the styles in the same chronology that archaeologists have ordered them in by inspecting which appear on top of which."
Note: "Arnhem Land has been occupied by Aboriginal peoples for tens of thousands of years and is the location of the oldest-known stone axe, which scholars believe to be 35,500 years old." (Wikipedia) Closed to tourists, the region is one of Australia's last true wilderness areas and I can only imagine what it must have been like trying to survive there ten thousand years ago.
Video from 2015. Did Amelia Earhart and navigator Fred Noonan crash or crash land on Nikumaroro island while attempting to fly around the world in 1937?
"Researchers at Penn State are subjecting an old, worn sheet of aluminum to a particle beam from the heart of a nuclear reactor in the hopes of cracking the mystery of Amelia Earhart's disappearance." Source: Live Science.
"... In 1991, Earhart enthusiast Richard Gillespie found an aluminum panel in washed-up storm debris on the Pacific island of Nikumaroro, about 300 miles (480 kilometers) from Howland [Howland Island -- the next stop in Earhart's 2nd attempt to fly around the world in 1937]. Gillespie has said he suspects the panel may have come from Earhart's plane, and now a Penn State team is using a neutron beam to — they hope — uncover hidden clues that might support that hypothesis."
"For the first time, biologically-relevant organic molecules have been detected in Archaean fluid inclusions, which most likely served as nutrients for early life on Earth." Source: Science Daily.
"... Specifically, the scientists examined about 3.5 billion-year-old barites [a type of mineral] from the Dresser Formation in Western Australia. The barite thus dates from a time when early life developed on Earth. 'In the field, the barites are directly associated with fossilized microbial mats, and they smell like rotten eggs when freshly scratched. Thus, we suspected that they contained organic material that might have served as nutrients for early microbial life,'" according to one of the researchers.
Note: There's a lot of informed speculation involved here. "...the team identified organic compounds such as acetic acid and methanethiol, in addition to gases such as carbon dioxide and hydrogen sulfide. These compounds may have been important substrates for metabolic processes of early microbial life. Furthermore, they are discussed as putative key agents in the origin of life on Earth." (Emphasis added) In other words, their findings are still inconclusive to a certain extent.
The Archean is a really ancient period and not much is known about it. According to current models of the Archean environment, there wasn't a lot of free oxygen in the atmosphere back then and the Earth was about the same temperature as it is today despite the fact that the sun's power output was around 70 percent less intense (the Faint Young Sun Paradox). Researchers believe that life appeared in the early Archean or late Hadean, the geological eon which started with the formation of the planet around 4.6 billion years ago. The emergence of microorganisms so early is pretty remarkable since the Earth hadn't even cooled enough to support life until around 3.8 billion years ago. Most of this early history is still hypothetical, but there's no doubt that life first emerged that long ago.
This isn't the first time that evidence of microbial mats has been discovered in Archean deposits. Colonies of simple microorganisms definitely existed back then. The evolution of more complex life forms may have been a freak accident, but the most important question is how and why life appeared in the first place. We have hard evidence that organic life emerged from the inorganic environment of the very early planet -- the only other possibility that I can think of is that the first microorganisms drifted here from space. If we're talking about a strictly terrestrial phenomenon, however, then it would seem that life is just a runaway chemical reaction.
"The oldest-known animal drawing in the world is a 45,500-year-old depiction of a hairy, warty pig on a cave wall in Indonesia, a new study finds." Source: Live Science.
"The mulberry colored painting, drawn with the red mineral ochre, shows the profile of what is likely a Sulawesi warty pig (Sus celebensis), a wild stubby-legged beast with facial warts that can weigh up to nearly 190 pounds (85 kilograms). These pigs 'are still found there today, although in ever-dwindling numbers,' said study co-lead researcher Adam Brumm, a professor of archaeology at Griffith University's Australian Research Centre for Human Evolution."
"The finding provides more evidence that ancient Indonesia was a hot spot for rock art, and that 'the first rock art traditions probably did not arise in ice age Europe as long supposed,' Brumm told Live Science in an email."
"Archaeologists have discovered the rare burial of a young child who was laid to rest 8,000 years ago without arm and leg bones, a new study finds." Source: Live Science.
"The child, who was no older than 8, was buried on what is now Alor Island, Indonesia. During the burial ceremony, the long bones in the child's arms and legs were removed and disposed elsewhere, and part of the child's face was painted with red ochre, a pigment often used in burials across the ancient world."