Early Hominins: Ardi, Lucy & Bipedalism

• Ardi (Ardipithecus ramidus) is an early hominin species that lived in woodlands and could walk upright and climb.

Ardi and Bipedalism

• Ardi's small canine teeth suggest reduced male conflict and increased pair bonding.
• The study of Ardi suggests that bipedalism was not solely driven by a lack of trees.
• Various theories propose bipedalism developed for efficient movement, carrying food, or male displays.
• Bipedalism provided a reproductive advantage, leading to diverse hominin species.

Australopithecus Afarensis

• Lucy belonged to Australopithecus afarensis, a species dated from 3.5 to 1.8 million years ago.
• Australopithecine fossils are mainly from southern or eastern Africa's volcanic areas.
• They are believed to have lived throughout Africa, had small brains (400-500 cc).
• They also exhibited sexual dimorphism and bipedalism.

The Bush Savanna and Genus Homo

• A cooling period around 2.5 million years ago saw the emergence of early Homo species.
• Homo species had larger brains, shorter arms, smaller guts and include H. rudolfensis, H. habilis, and H. ergaster.
• Early Homo is associated with Olduwan stone tools found in the Olduvai Gorge.
• Homo species are characterized by tool use, independence from trees, and rapid brain growth.
• By 2 million years ago, both australopithecines and Homo species lived in open landscapes.

Homo Erectus

• H. erectus emerged about 1.8 to 1.7 million years ago and was more human-like in appearance.
• H erectus skeletons have been found worldwide, excluding the Americas.
• Early H. erectus skeletons are sometimes referred to as H. ergaster.
• H. erectus skeletons were almost as tall as modern humans, with about 70% of our brain size.
• H. erectus had full bipedalism, shorter arms, and semicircular canals for balance.
• The pelvis narrowed, aiding bipedalism but reducing the birth canal size.

Changes in Childbirth, Pair Bonding & Fire

• H. erectus infants were born earlier due to brain size, requiring more care.
• Pair bonding and cooperation developed for infant care and protection.
• Male skeletons of H erectus were about 25% larger than females.
• This indicates less male competition.
• H. erectus people likely used fire for cooking and food preservation.
• This reduced chewing time and may have allowed brain expansion.
• Fire use, a distinctive human trait, fueled further developments and skill in tool making (Acheulian tools).
• Homo Erectus were the first hominine species to venture out of Africa.
• H. erectus groups evolved into Neandertals in glacial Europe.

Skin Color & Offshoots of Homo Erectus

• Another change in the H erectus era was the darkening of skin color to protect against UV radiation.
• H. floresiensis ("hobbits") were found east of Java.
• Denisovans were found in Denisova Cave, distinct from both Neandertals and modern humans.

Hominine Evolution Summary

• Over 7 million years, hominine spines straightened, pelvises narrowed, and brains grew larger.
• Pair bonding, communication, and cooperation increased.
• The descendants of H. erectus evolved differently across Afro-Eurasia, leading to Neandertals and H. sapiens.

Determining the Arrival of Homo Sapiens

• A threshold is crossed when minor changes lead to new emergent properties.
• A historical approach, focusing on the species as a whole, reveals differences between humans and other animals.
• Human relationship with the environment has changed.
• Most species have unchanging behaviors, while humans have a history of radical behavior changes.

Human Adaptation and Expansion

• Humans exploit many new environments and migrate over large areas.
• Human populations have multiplied.
• Humans reshape environments, leading to the Anthropocene epoch.

Distinctive Traits of Human Ancestors

• Our ancestors found new ways to adapt to environments.
• They control more energy and resources and use technologies.
• H. erectus and H. ergaster had limited technologies.
• Humans have the astonishing ability to adapt to environments in new ways.

Teamwork and Symbolic Language

• Teamwork is the source of ecological and social creativity.
• Humans can collaborate and communicate using symbolic language.
• Humans share information and ideas efficiently.
• Groups can pool discoveries and innovate.

How Symbolic Language Works

• Humans can communicate about past, future, and hypothetical events.
• Symbolic language allows reference to whole categories of ideas.
• Syntax conveys multiple relationships between people, things, and ideas.
• Shared information accumulates across generations, driving behavioral changes (history).
• Collective Learning results from symbolic language.
• Collective Learning is the key to understanding threshold 6.

Threshold 6 Summary

Ingredients

• Same as all life and highly developed manipulative, perceptive, and neurological capacity

Structure

• Highly specific biological structures governed by human DNA

Goldilocks Conditions

• Long preceding period of revolution generating highly developed manipulative, perceptive and neurological capacity

Emergent Capacity

Emergent Properties

• Collective Learning that is capacity to share information precisely so it accumulates giving rise to long term historical change

When and Where Did Homo Sapiens Appear?

• Our species emerged in the Middle Paleolithic, between 250,000 and 50,000 years ago.

When Human History Began

• Symbolic language and Collective Learning appeared.

What Is the Evidence?

• Spoken language leaves no direct trace.
• Many skills are required for human language (brain power, sound management, theory of mind).

Genetics and Language

• A family study linked grammar difficulty to a mutation on the FOXP2 gene.
• The human form of FOXP2 appeared within the last 200,000 years.
• Neandertals shared the same FOXP2 gene.
• Archaeological record remains patchy, impeding conclusions.
• In the last million years we have evidence of many species of hominines and many descend from H. erectus

Homo Sapiens Evolution

• The Out of Africa and multiregional hypotheses seek to explain modern human branching.

Out of Africa

• The theory that modern humans evolved in Africa

Multiregional Hypothesis

• The theory that presume there was contact between hominine that meant the whole area remained 1 large group

Archaeological vs Genetics

• Archaeological and genetic studies support "Out of Africa".
• DNA from Neandertals showed they are distinct, diverging ~500,000 years ago.
• Modern humans are remarkably similar genetically speaking.
• There is greater genetic variety in Africa, an indicator suggesting that this is where the species first appeared

Africa vs Eurasia

• Skulls from Omo, Ethiopia are essentially modern human skulls, dated almost 200,000 years ago.
• Skeletal remains from Africa date from about 125,000 years ago.

Skeletal Features of Modern Humans:

• Cranial capacity usually over 1,350 cc
• Relatively vertical frontal bone (forehead)
• High and parallel-walled cranial vault Rounded occipital region lacking a prominent bulge and with a relatively flat angle of the cranial base Non-continuous brow ridge expressed more clearly in males Relatively flat, non-projecting face "tucked in" below the frontal region

Distinct Chin

Archaeological innovation by Time Period

• Most scholars accept that our species evolved in Africa within the last 250,000 years.
• Human artifacts appear later than human bodies.
• Technological innovation shows from about 50,000 years ago (Upper Paleolithic).
• Tools diversify, new materials appear, and art objects emerge.

Species Capable of Collective Learning

• The diversification of technologies, increased sharing, and accelerated innovation mean that this species is capable of Collective Learning at the time.
• Art objects suggests these humans were thinking in symbolic language as well.
• The changes occurring from about 50,000 years ago is called "Revolution of the Upper Paleolithic."

Timeline of Human History

The Paleolithic Era

• This takes us to human history proper although it is not often considered for a variety of reasons

Significance of This Early period and Timeline

• It is the period in which we became we are, who we are.
• Without it all subsequent history, the 5 % latest human history doesn't make sense.
• Only about 12 percent of all humans have ever lived in this period which partly explains the neglect of that period of time by history books
• 2 "events" that changed human evolution and evolution of society at this time

Climate Change 200,000 Years ago

• Humans have survived two major ice ages.
• The human lifeway evolved under the ice age environment
• From 11,500 Earth became warmer.
• Ice sheets melted vegetation becoming lusher They were crucial in the domestication of plants.

Migration from collective learning and new Tech

• Through that learning humans were able to migrate and adapt to new regions

Extensification as Global Colonization

• Increase in the range of humans without any parallel the average size or density of human communities Humans by product of that learning started to extract and change their environment with what they learned Humans by this timeline had adapted to cold

What about Human life During the Extensification

• By all accounts they were far from primitive
• It is from this period that the development and origin of the 200,000 yers old and older.
• The humans of this time period would have required the information taught by their community to extract for there environment.

Generalizations

• The evidence of these people come from sites including bones, tools, remains Foraging - gathering and storing food
• Term interchangeable with hunter gatherering.

How does the new information change life style

• Some move to warmer environments , some cooler, some general, some are stationary for some seasons Populations need to be kept small and communities need to have large territories and maintain low breeding numbers.
• In these early times they used birth control

Plants vs Animals

• The diet was dependent on location.
• Some hunting and gathering - The people were mainly scavenging, or hunting small creatures etc

Foraging and living

• The Inuit prospered in regions because of use of all local items like bones to store food
• Cave findings in Ukraine give clues to housing from 200,000 years ago
• 2 simple techniques for that period of travel and living include the Inuit and The San

San and Early humans

• Modern humans lived nasty, brutish and short lives."
• The work of "San", revealed that they enjoyed the simple hunter gather lifestyle

Most People Lived

How did social structure begin?

• Small groups usually. family was the most basic unit of society - a core community Corroboree is a good example of a meeting of tribes to exchange pleasantries and goods. The social groups remained in the dozens as there were less things to trade. Life in that period remained" Do it yourself"" and relied heavily on family.

Gender relations emerged

• The main thought was males are to hunters , females as gatherers.
• Recent Scholarship seems to vary this assumption where it now suggests that genders had flexible conditions
• Paleolithic Ideologies of how these genders work have never been observed or recorded. In short what is known is that humans back then probably saw themselves as intertwined with nature. But it is still left up to perception.

Ancient Art

• Some of the earliest art sites in the world include cave paintings, etc

Did Art Exist Before?

• Although art has been seen and studied over many millinea art started with The Sun and a few clay pots of women

Palleolithic impact today

• Firestick farming and the hunting/extinction of large animals. Early humans expanded quickly by taking what they needed to prosper in their new environment

Cave paintings and humans

• Early Humans are thought to have spread and diversified quickly, due to all of the "lessons and training mentioned at the start of the notes!

End of Notes