Lice have been the subjects of significant DNA research that has led to discoveries on human evolution.

For example, recent DNA evidence suggests that pubic lice spread to humans approximately two million years ago from gorillas.

Additionally, the DNA differences between head lice and body lice provide corroborating evidence that humans started losing body hair, also about two million years ago.

Genetic analysis suggests that the human body louse may have originated about one hundred and seven thousand years ago from the head louse after the invention of clothing, with the ancestor of all human lice emerging about seven hundred and seventy thousand years ago.

The Moderns are taller, more slender, and less muscular than the Neanderthals, with whom they share—perhaps uneasily—the Earth.

Though their brains are smaller in overall size, they are heavier in the forebrain, a difference that may allow for more abstract thought and the development of complex speech.

Yet, the inner world of the Neanderthals remains a mystery—no one knows the depths of their thoughts or how they truly expressed them.

Y-chromosomal Adam, the patrilineal most recent common ancestor, is the male counterpart of Mitochondrial Eve, although they lived thousands of years apart: Y-chromosomal Adam and Mitochondrial Eve need not have lived at the same time.

In human genetics, Y-chromosomal Adam (Y-MRCA) is the most recent common ancestor (MRCA) from whom all living people are descended patrilineally (tracing back only along the paternal lines of their family tree)

Recent studies report that Y-chromosomal Adam lived as early as around one hundred and forty-two thousand years ago: older studies estimated Y-MRCA as recent as sixty thousand years ago.

Mitochondrial Eve in the field of human genetics refers to the matrilineal most recent common ancestor (MRCA) of modern humans.

She, in other words, is the woman from whom all living humans today descend, on their mother's side, and through the mothers of those mothers and so on, back until all lines converge on one person.

Because all mitochondrial DNA (mtDNA) is generally passed from mother to offspring without recombination, all mitochondrial DNA (mtDNA) in every living person is directly descended from hers by definition.

Each ancestor (of people now living) in the line back to the matrilineal MRCA had female contemporaries such as sisters, female cousins, etc., and some of these female contemporaries may have descendants living now (with one or more males in their descendancy line), but none of the female contemporaries of the "Mitochondrial Eve" has descendants living now in an unbroken female line.

Mitochondrial Eve is estimated to have lived around two hundred thousand years ago, most likely in East Africa, when Homo sapiens sapiens were developing as a population distinct from other human sub-species.

The foundation population of the humans that today inhabit the world are the survivors of what appears to be an evolutionary bottleneck caused by a global catastrophe during the period that begins around 90,000 BCE.

The Toba supereruption (Youngest Toba Tuff or simply YTT), a supervolcanic eruption that occurs some time between sixty-nine thousand and seventy-seven thousand years ago at Lake Toba in Sumatra, Indonesia, is recognized as one of the Earth's largest known eruptions and is the most closely studied supereruption.

The related catastrophe hypothesis holds that this event plunged the planet into a six-to-ten-year volcanic winter and possibly an additional one thousand-year cooling episode.

This change in temperature results in the world's human population being reduced to ten thousand or even a mere one thousand breeding pairs, creating a bottleneck in human evolution.

Consistent with the Toba catastrophe theory, evolutionary biologist Richard Dawkins has postulated that human mitochondrial DNA (inherited only from one's mother) and Y chromosome DNA (from one's father) show coalescence at around one hundred and forty thousand and sixty thousand years ago, respectively.

In other words, all living humans' female line ancestry traces back to a single female (Mitochondrial Eve) at around one hundred and forty thousand years ago.

All humans can trace their ancestry with certainty via the male line back to a single male (Y-chromosomal Adam) at ninety thousand to sixty thousand years ago.

Anatomically modern and behaviorally modern humans in the southernmost tip of southern Africa inhabit the Klasies River Caves, a series of caves located to the east of the Klasies River mouth on the Tsitsikamma coast in the Humansdorp district of Eastern Cape Province, between 80,000 and 110,000 BCE.

There is a marked difference between the Paleolithic stone technology used in the earliest layers from one hundred and twenty-five thousand years ago years ago, and the superior Mesolithic blades of the seventy-thousand-year-old Howiesons Poort period that used raw material which had been 'mined' twenty kilometers inland.

There is also a differentiation between the Paleolithic food detritus that accumulated underfoot inside the caves one hundred and twenty-five thousand years ago, but is ejected and accumulated into external middens by the Mesolithic occupants circa seventy-five thousand years ago: housekeeping has now become standardized.

Homo sapiens sapiens apparently spreads rapidly from sub-Saharan Africa across the Sahara Desert and into the Near East, where the new species flourishes by 88,000 BCE.

The rapid expansion of anatomically modern humans out of Africa, beginning around 60,000 years ago, appears to coincide with the development of new stone tool-making techniques.

These innovations, which define the Upper Paleolithic period, distinguish the stone tool culture of Homo sapiens sapiens from the previously similar technologies of Neanderthals and other archaic human groups.

Key advancements include:

• The production of long, narrow flake tools, known as blades, which could be fashioned into a variety of specialized tools,
• The emergence of bone and ivory artifacts, and
• The eventual development of clothing, often sewn together and adorned with beads.

These technological advancements likely played a crucial role in the success and adaptability of early modern humans as they spread across new environments.

The history of indigenous Australians is thought to have spanned forty thousand to forty-five thousand years, although some estimates have put the figure at up to seventy thousand years before European settlement.

A genetic study of one hundred and eleven Aboriginal Australians, published in the journal Nature on March 8, 2017 (Aboriginal mitogenomes reveal 50,000 years of regionalism in Australia), implies that "the settlement of Australia comprised a single, rapid migration along the east and west coasts that reached southern Australia by 49–45 ka. After continent-wide colonization, strong regional patterns developed and these have survived despite substantial climatic and cultural change during the late Pleistocene and Holocene epochs. Remarkably, we find evidence for the continuous presence of populations in discrete geographic areas dating back to around 50 ka, in agreement with the notable Aboriginal Australian cultural attachment to their country.”

For most of this time, the Indigenous Australians lived as nomads and as hunter-gatherers with a strong dependence on the land and their agriculture for survival.

Only Africa has older physical evidence of habitation by modern humans.

There is also evidence of a change in fire regimes in Australia, drawn from reef deposits in Queensland, between seventy thousand years and one hundred thousand years years ago, and the integration of human genomic evidence from various parts of the world supports a date of before sixty thousand years for the arrival of Australian Aboriginal people in the continent.

Modern humans reach Australia by at least 58,000 BCE.

In 1990, a date of sixty thousand years was suggested for a rock shelter in the Northern Territory, but the finding, based on the use of a recently developed technique called thermoluminescence, is still being evaluated.

The first settlement would have occurred during an era of lowered sea levels, when there was an almost continuous land bridge between Asia and Australia, but watercraft must have been used at some points.

Modern humans begin to move out of the Horn of Africa, some traveling south, others moving east into Arabia along the Indian Ocean’s 'Coastal Express' route, eventually to arrive in Australia; others penetrate northeast into West Asia, a route presumably rendered impassable in former times by tough, strong, spear-wielding Neanderthals.