Agriculture of the Earliest Humans

Agriculture of the Earliest Humans

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Humanity is a product of the evolutionary forces which drove incremental improvement over the course of millions of years.

From the humble beginnings of Australopithecus to the emergence of modern Homo sapiens, each step of our evolutionary journey tells a tale of adaptation and survival—a testament to the indomitable spirit of the human race.

Driven by the most fundamental of needs to feed and nourish themselves, early humans set the foundation for all advances in agriculture that would guide humanity’s future for millennia to come. To understand where we are today, we must start with our origins and unravel the mystery of our past – a past which illuminates the journey of agriculture that enables us to be the extraordinary beings we are today.

Early-Human Ancestors: Australopithecus

In the quiet dawn of the African savannah, where the sun stretched its golden fingers across the horizon, this story as ancient as time began to unfold. It is a tale of resilience, adaptation, and the relentless pursuit of progress—a narrative that belongs to none other than us: the early humans.

As the morning mist dissipated, the first rays of sunlight illuminated the silhouette of a creature unlike any other. Driven by an insatiable quest for knowledge, exploration, and the need to feed itself, this early human explored the unknown with a keen gaze and deft hands. It was a journey fraught with challenges and uncertainties yet filled with moments of triumph and innovation.

This creature has since come to be known as Australopithecus afarensis – the mother species of all modern humans.

Australopithecus afarensis

 

Australopithecus means “apes of the south” and it is believed that lived between 6.5 and 1.5 million years ago. These fascinating creatures emerged during the Pliocene and Pleistocene epochs, showcasing a blend of both ape-like and human-like characteristics. From these beginnings, the journey toward modern humans begins.
 
This earliest form of human holds a crucial place in the evolutionary timeline, representing a significant leap in the development of early humans. 

Australopithecus is renowned for being one of the earliest known bipedal primates, displaying upright posture and locomotion—an adaptation that paved the way for subsequent human evolution. But the most important evolutionary developments are the larger brains of this species and the development of hands which became crucial for manipulating objects within the environment.

Australopithecus had a brain mass approximately half the size of homo sapiens and overall were around one-third the size of modern man

Habitat Range of Australopithecus

Australopithecus is believed to have lived in various regions of Africa, including present-day Ethiopia, Kenya, Tanzania, and South Africa. Fossil discoveries indicate their presence in wooded habitats, grasslands, and savannas.

Australopithecus Habitat & Range

 

It is within these grasslands and savannahs of Africa that we understands what the diet of Australopithecus consists of.

The most famous example of Australopithecus comes from the Lucy specimen which are the fossilized remains of an early hominid, was discovered on November 24, 1974. The discovery was made by paleoanthropologist Donald Johanson and his team in the Afar Depression of Ethiopia. Lucy’s remains are about 3.2 million years old and give us insights into the makeup, size and dietary preferences of this early human species. 

Additional fossil remains have been discovered primarily in East Africa, notably in sites such as Laetoli and Hadar, providing invaluable insights into our ancestral past.

The First Tools of Agriculture

Not surprisingly, the first tools of agriculture were simple implements made of rock. Australopithecus likely used simple percussion or smashing of rocks to create these tools which were likely used for basic cutting of plants and opening of nuts and other plant derived foods. It is unlikely that Australopithecus used tools for any type of hunting or cutting of animals, given their dietary preferences matching early-human herbivores.

Early-Human Agriculture: Eating Habits of Australopithecus

Understanding the eating habits of Australopithecus provides us with the first intriguing insights into human agriculture and the dietary preferences foundational to human survival since the earliest times.

Unsurprisingly, Australopithecus was a forager, like most all forms of animal life before it. Our earliest human ancestor was most likely an herbivore. Fossil evidence and studies of dental morphology suggest that Australopithecus primarily subsisted on a diet rich in fruits, nuts, seeds, and occasionally insects. 

It has been discovered that the thick enamel of Australopithecus teeth likely had been an adaptation to eating ground based foods such as tubers, roots and some grains. This diet, largely composed of plant-based foods, reflects the availability of resources in their environment, which consisted of forests, woodlands, and grasslands. Some examples of plants that Australopithecus may have eaten that are still around today include certain fruits like figs, nuts like acorns, and various leafy greens.

There is some evidence to suggest that Australopithecus may have also eaten small rodents and insects to supplement its diet as well.

However, what is particularly noteworthy is the emphasis on a varied diet for their survival. Australopithecus exhibited a remarkable ability to adapt to fluctuating food sources, likely due to environmental changes or seasonal variations. Calories from one type of food, be it nuts or roots, would inevitably exhaust itself in the local area, forcing Australopithecus to seek multiple sources rather than a single type of food. By consuming a diverse range of foods, Australopithecus also ensured that they obtained essential nutrients, vitamins, and minerals necessary for optimal health and reproduction. 

This dietary flexibility not only enhanced their resilience in challenging environments but also laid the foundation for the evolutionary success of our species modern species. Furthermore, the importance of a varied diet likely contributed to the development of complex foraging behaviors and social dynamics within Australopithecus populations, fostering cooperation and resource sharing among individuals. 

In essence, the dietary habits of Australopithecus underscore the critical role of adaptability and dietary diversity in the evolutionary journey of early humans. It was this trait to forage and adapt which helps enhance the survivability of this species.

Insights into their Lifestyle and Behavior

Beyond dietary preferences, the lifestyle and behavior of Australopithecus offer intriguing glimpses into their social dynamics and cognitive abilities. Evidence suggests that they lived in social groups, engaging in cooperative behaviors such as communal caregiving and group foraging. 

Additionally, their use of rudimentary tools, albeit primitive compared to later hominins, hints at early forms of problem-solving and tool manipulation—a precursor to the technological advancements that would characterize human evolution.

In essence, Australopithecus stands as a testament to the ingenuity and adaptability of our early human ancestors, marking the dawn of a transformative journey that continues to shape our understanding of human origins and evolution.

The First Early-Humans: Homo habilis

As the eons passed, the Australopithecus lineage continued to evolve. Smarter, more adept and closer to modern humans our ancestors moved forward in their evolutionary progression. Among them emerged a remarkable group of individuals, distinguished by their ingenuity and resourcefulness. 

Homo habilis emerged as the next successful product of human evolution and is considered the first true human species.Homo habilis lived during the Pleistocene era approximately 2.4 to 1.5 million years ago and coexisted with Australopithecus in the East Africa region.

Homo habilis

 As an early member of the Homo genus, Homo habilis had to adapt to diverse environments and develop unique eating habits to survive and thrive. These were the pioneers of their time, the ancestors of a new lineage destined to shape the course of human history.

These creatures were the first known hominids to combine their larger brains, opposable thumbs and stone objects to shape the way they interacted with the surrounding environment. From this we derive their namesake – Homo habilis, literally meaning “handy man”. Homo habilis brain is estimated to have been approximately one-half the size of modern humans.

Tools of Homo Habilis

In the rocky outcrops scattered across the landscape, this individual found tools—sharp-edged stones crafted through careful manipulation. These stone tools were not just artifacts; they were symbols of a profound cognitive leap, a testament to the growing intelligence and adaptability of our lineage. With these newfound implements, our ancestor unlocked a world of possibilities and unlocked the nascent power of agriculture with it.

In all likelihood, these early stone tools were fashioned using percussion and beating to attain a desired shape – likely one with sharp edges and a reasonable size for cutting.

Early Stone Tools

 

With a keen eye and nimble hands, this proto-human discovered the transformative power of stone in many ways. This trait allowed them to grasp and manipulate objects with precision, which was likely advantageous for tasks such as toolmaking, gathering food, and other activities essential for survival. Naturally, with the combination of opposable thumbs and stone derived instruments likely gave way to the first tools used within agriculture.

Their tool use, particularly the simple stone tools associated with Homo habilis, suggests they may have used these implements for processing and accessing food. For example, they could have used sharp-edged stones to butcher animal carcasses or crack open bones to access marrow. This ability to modify their environment and manipulate tools likely expanded the range of food sources available to them.

These implements included simple flakes and cores, which they likely used for tasks like butchering meat and processing plant materials. This technological innovation represented a significant advancement in hominin evolution, enabling them to access new food resources and better adapt to their environment.

These early-humans could now hunt more efficiently, gather food more effectively, and defend themselves against predators.

Habitat Range of Homo habilis

The habitat range of Homo habilis is believed to have been predominantly in East Africa which includes broad swaths of land ranging from the Red Sea in modern Ethiopia to the highlands of South Africa.

Habitat Range of Homo habilis

Fossil evidence suggests that Homo habilis inhabited a variety of environments, including woodlands, grasslands, and mixed habitats, indicating a degree of adaptability to different ecological conditions. 

Homo habilis likely preferred areas with access to water sources and diverse vegetation, where they could hunt, gather food, and find shelter. However, their range and specific habitat preferences may have varied over time as environmental conditions changed and as Homo habilis adapted to new challenges and opportunities.

Early-Human Agriculture of Homo habilis

In the ancient landscapes of Africa, where Homo habilis roamed, food was not readily available like it is in modern times. While we cannot observe their eating habits directly, scientists have drawn insights from various sources, including fossilized remains, archaeological evidence, and comparisons with modern primates and hunter-gatherer societies.

Similar to Australopithecus, plant foods would have been an important part of their diet, including fruits, nuts, seeds, roots, and tubers. These would have been gathered from the surrounding environment, likely supplemented by opportunistic foraging and scavenging. Fruits and other plant foods provided essential nutrients, vitamins, and energy sources necessary for survival.

Homo habilis

Archeological evidence shows that their teeth and jaws contained a combination of features suited for processing a range of foods. For instance, they had larger molars for grinding plant material and tougher foods, as well as relatively sharp incisors. These incisors, most adept at cutting meat, give us insight into one of the great leaps in human evolution: the consumption of meat and representing a new epoch in humanity’s journey through agriculture.

Thus, Homo habilis was likely omnivorous, consuming both plants, however, it is believed they also consumed a great deal of meat. Most likely, they scavenged from the corpses of dead animals hunted by prey or killed through other causes. 

While they were not as proficient hunters as later Homo species, they likely exploited opportunities to scavenge carcasses left behind by other predators or hunted small animals such as rodents, birds, or even scavenged larger kills made by other carnivores. However, this early appetite for meat consumption paved the way for more advanced hominids to hunt animals for food and the ultimately the domestication of animals and herding for meat and by-products.

Overall, Homo habilis exhibited a flexible and adaptable approach to eating, relying on a varied diet of both plant and animal foods to meet their nutritional needs in the challenging and ever-changing environments of early Africa. Their dietary flexibility and ingenuity were crucial factors in their success as early humans and laid the foundation for the dietary adaptations seen in later Homo species, including modern humans.

Homo erectus

Through eons of evolution, the numbers of Homo habilis slowly dwindled. However, amidst the sweeping grasslands and scattered woodlands, a new species emerged to take their place from the shadows of its ancestors. 

Homo erectus literally means “standing man”. Tall and agile, with a physique built for endurance and exploration, Homo erectus marked a significant leap forward in the journey of humanity. As the descendants of Homo habilis, Homo erectus inherited a legacy of innovation and adaptation. 

Homo erectus emerged in Africa approximately 1.8 million years ago and is noteworthy for being the first human species to venture out of the continent and inhabit large portions of Eurasia.

Homo erectus - early human pioneer of agriculture. 

This species pushes the boundaries of what it meant to be human. With each passing generation, they honed their skills, refined their tools, and ventured farther into the unexplored territories of the Earth.

One of the defining features of Homo erectus was their remarkable ability to walk and run over long distances. Their legs were elongated, their hips were sturdy, and their stride was efficient. This newfound mobility allowed them to explore vast area, track migrating herds, and seek out new sources of food and shelter.

 

Human Revolution of Homo erectus

But it wasn’t just their physical attributes that set Homo erectus apart—it was their intellect, their ingenuity, and their capacity for innovation. They were the first hominins to harness the power of fire, a discovery that would revolutionize their way of life and the history of agriculture along with it. With fire, they could cook food, stay warm during cold nights, and ward off predators. It was a transformative tool that fueled their expansion and shaped their destiny.

As Homo erectus spread across the ancient world, they encountered a diverse array of environments and challenges. From the lush forests of Asia to the rugged coastlines of Europe, they adapted and thrived in a wide range of habitats. Their resilience, adaptability, and resourcefulness were the hallmarks of their success.

The emergence of Homo erectus marked a turning point in the story of human evolution. It was a time of exploration, of innovation, and of boundless potential. From their humble beginnings in Africa to their global conquest of the planet, Homo erectus paved the way for the rise of modern humans and left an indelible mark on the history of our species.

Habitat and Range of Homo erectus

Homo erectus was truly the first transcontinental of the hominids. In their quest for new living spaces, homo erectus settled in areas ranging from the northeastern parts of Europe, through the southern tip of Africa and into the fertile river valleys of China and India.

Homo erectus habitat and range.

 

This migration was most likely driven by shifts in climate and environment. Changes such as periods of cooling and drying could have reduced forested areas and expanded grasslands, prompting them to follow animal herds and search for new resources.

Furthermore, as populations grew, competition for resources such as food and water would have increased. Moving to new areas could alleviate local resource pressures and provide access to abundant food and new habitats.

Eating Habits of Homo erectus

As an evolutionary offshoot of Homo habilis, Homo erectus was also an omnivorous species and consumed a diverse diet consisting of both plant and animal matter. Their adaptive nature allowed them to exploit a wide range of food resources available in their environments.

Plant foods played a significant role in the diet of Homo erectus. They would have gathered a variety of fruits, nuts, seeds, roots, and tubers from the surrounding landscape. These plant-based foods provided essential nutrients, vitamins, and carbohydrates necessary for energy and sustenance. Homo erectus likely utilized their tool-making abilities to harvest and process plant foods, perhaps using sharp-edged stones to cut through tough vegetation or crack open nuts and seeds.

However, it was the inclusion of animal protein in their diet that likely played a crucial role in the evolutionary success of Homo erectus. With their hunting and scavenging abilities, Homo erectus would have targeted a wide range of prey, including small mammals, birds, fish, and even larger game. 

Homo erectus likely hunted large game, including rhinoceros, bear and possibly elephant. This type of hunting involved small group hunting which necessitated social hierarchies and coordination among the members of the group.

They may have used tools such as spears, clubs, or sharpened stones to hunt or scavenge for animals, and their ability to control fire would have facilitated cooking and processing of meat, making it more easily digestible and reducing the risk of pathogens.

One of these tools is likely biface – typically formed from flint – where a stone blade would have symmetrical properties for better piercing and cutting capabilities.

Biface is an early tool marked by symmetrical cuts for better piercing and cutting.

 

The utilization of fire by Homo erectus was a significant development in their dietary habits. This fire was most likely natural, as opposed to artificial, in origin. Natural sources of fire would have included fire from lightning strikes and swap fire and thus reliable only in certain circumstance. No evidence suggests that Homo erectus utilized flint strikes for fire creation, which was likely discovered by later humans.

What is critical about fire is in the realm of human agriculture is its effect on cooking. Cooking not only made meat safer to eat but also increased its caloric value and nutritional availability. The mastery of fire allowed Homo erectus to expand their diet to include a wider variety of foods, contributing to their ability to thrive in diverse environments and adapt to changing climates.

Greater amounts of calories ultimately meant healthier populations and the ability to support larger brains, thus continuing the march of human evolution forward. 

Neanderthals: Homo Neanderthalis

Homo neanderthalensis, commonly known as Neanderthals, emerged as the result of human evolution approximately 400,000 years ago and represents a fascinating branch of the human evolutionary tree.

Neanderthals (Homo neanderthalensis) are believed to have emerged approximately 400,000 to 600,000 years ago. They evolved in Europe and parts of western Asia, where they adapted to the cold climates of the Pleistocene epoch. Neanderthals existed until about 40,000 years ago, when they were eventually replaced by or assimilated into the populations of modern humans (Homo sapiens) who had migrated into their territories.

Neanderthals were robust, physically strong hominins well-adapted to the harsh environments of the Pleistocene era. Their distinctive anatomical features, such as prominent brow ridges and stocky builds, set them apart from other contemporary human species. Truly remarkable were the cognitive abilities of Neanderthals with brain masses and intelligence on parity with that of modern human beings.

 

Introduction to Homo Neanderthalis and their Unique Characteristics

Neanderthals were remarkable for their adaptability to diverse environments, ranging from the frigid landscapes of Ice Age Europe to the temperate forests of the Mediterranean. Their unique physiological traits, including large nasal cavities and barrel-shaped chests, were well-suited for cold climates, allowing them to thrive in regions where other hominin species might struggle to survive. 

Moreover, evidence suggests that Neanderthals possessed complex social structures, engaging in activities such as burial rituals and caring for the infirm within their communities.

Habitat and Range of Neandertals

Neanderthals lived primarily in Europe and parts of western Asia, including regions that are now present-day France, Spain, Germany, Croatia, and the Middle East. Fossil evidence indicates that they inhabited diverse environments, ranging from cold, tundra-like regions to more temperate forests and grasslands. Neanderthals were well-adapted to these environments and demonstrated a remarkable ability to survive and thrive in a variety of ecological niches.

Neandertal Habitat and Range

 

Neandertal Habitat and Range.

Some evidence suggests Neandertals migrated far into Central Asia, though this fact is disputed. The local plants and animal species of this area were diverse; as such, Neandertals adapted to many different food sources across the their range of habitation.

Eating Habits of Neanderthals

The eating habits of Neanderthals offer a fascinating glimpse into the dietary adaptations of our ancient human relatives. Unlike their contemporaries, Neanderthals were primarily carnivorous, with a diet heavily reliant on meat from large game animals such as mammoths, bison, and deer. Neandertals likely also ate several smaller animals such as rabbits, rodents and birds when the need arises as well.

Evidence of hunting strategies, such as the use of thrusting spears and stone-tipped weapons, suggests that Neanderthals were proficient hunters capable of taking down formidable prey. Additionally, traces of cut marks and evidence of butchery found on animal bones indicate sophisticated food preparation techniques, including skinning, dismembering, and possibly cooking. These findings not only shed light on the dietary habits of Neanderthals but also highlight their ingenuity and mastery of their environment.

However, recent archaeological discoveries have revealed that their diet was not exclusively meat-based; rather, it was supplemented with plants, including berries, nuts, tubers, and possibly grains. This combination of animal and plant foods reflects their ability to exploit a diverse range of resources in their environment, showcasing their adaptability and resourcefulness as skilled hunters and gatherers.

By leveraging their knowledge of local flora and fauna, Neanderthals were able to secure sustenance in the challenging landscapes of Ice Age Europe, contributing to their survival and eventual dominance in their respective habitats. Overall, the eating habits of Neanderthals underscore their adaptability, resourcefulness, and complex relationship with their environment, offering valuable insights into the evolutionary strategies employed by our ancient human relatives.

Comparisons with Other Early Humans and Implications for Survival

Comparisons between Neanderthals and contemporary human species, such as Homo sapiens, shed light on the diverse strategies employed by early humans to adapt to their environments. While Neanderthals were adept hunters capable of thriving in resource-rich environments, Homo sapiens, with their cognitive flexibility and social complexity, exhibited greater versatility in exploiting a wider range of habitats and food sources. The coexistence of these two human species in certain regions, such as Europe, suggests dynamic interactions shaped by competition, cooperation, and cultural exchange.

Understanding the dietary habits and lifestyle of Neanderthals provides valuable insights into the complexities of human evolution and the diverse pathways taken by different hominin species. By examining their adaptations to specific environmental challenges and their interactions with other human populations, we gain a deeper appreciation for our early human ancestors’ remarkable diversity and resilience.

Modern Man: Homo Sapiens sapiens

Imagine a world untouched by the footprints of civilization, where towering trees sway gently in the breeze, and the earth hums with the harmonious symphony of nature. Yet amidst this serene backdrop, a remarkable transformation was underway that would shape the course of history and define the very essence of humanity.

Homo sapiens, or modern humans, represent the culmination of an extraordinary evolutionary journey that spans hundreds of thousands of years. No other species has made such remarkable progress within a short timeframe as that of modern humans.

When Homo sapiens first appeared in Africa about 300,000 years ago, it was a turning point in the evolution of our species, with unique cognitive capacities, innovative technologies, and intricate social structures. Naturally, these improved cognitive capabilities enabled a major shift in how early humans fed and nourished themselves.

Evolutionary Milestones Leading to Homo Sapiens

Homo sapiens stem from the same evolutionary branch of Homo erectus. Between Homo sapiens and Homo erectus was a species known as Homo Heidelbergensis. This evolution took place approximately 300,000 years ago within Africa. The shift from species to species was gradual as opposed to immediate.  

Several significant evolutionary milestones marked the transition from our early hominin ancestors to Homo sapiens. One of the key developments was the emergence of bipedalism, which freed our hands for tool use and facilitated the exploration and exploitation of new environments.

Over time, Homo sapiens developed increasingly sophisticated tools and technology, including the use of fire, which provided warmth, protection, and a means of cooking food. This use of fire also enabled the heating of stone to form tools and alter the properties of small amounts of metals to create the first non-stone implements. These adaptations allowed Homo sapiens to expand their range and colonize diverse habitats across the globe.

Many of the inventions without practical survival attributes would indicate a surplus of foodstuffs enabling the creation of non-essential type objects, such as artwork, pottery and decorative devices. For the first time, the species had time apart from foraging and hunting to maintain a bare existence and explore the more creative aspects of their minds – a development which ultimately had the most profound impacts upon humans and the world at large.

Eating Habits of Homo Sapiens

The eating habits of early Homo sapiens mark a significant departure from those of our early ancestors, reflecting the remarkable adaptability and innovation that characterize our species. As Homo sapiens emerged and spread across different regions of the world, they diversified their diet to include a wide range of foods obtained through hunting, gathering, and eventually agriculture. In the early stages of human development, Homo sapiens relied on a hunter-gatherer lifestyle, foraging for wild plants and hunting animals for sustenance. However, with the advent of agriculture around 10,000 years ago, Homo sapiens underwent a profound dietary shift, transitioning from nomadic lifestyles to settled agricultural communities. This transition brought about a dramatic increase in the variety and availability of foods, as humans began cultivating crops such as grains, legumes, fruits, and vegetables and domesticating animals for meat, milk, and other products.

Representation of early homo sapiens harvesting in Africa.

Furthermore, the transition to agriculture spurred advancements in food preparation methods and cooking techniques. Homo sapiens developed innovative ways to process and cook food, enhancing its nutritional value, flavor, and digestibility. Cooking, in particular, played a crucial role in human evolution, allowing for the breakdown of tough fibers, the denaturation of toxins, and the killing of harmful bacteria, thus making food safer and more palatable. Homo sapiens also developed various food preservation techniques, such as drying, smoking, salting, and fermenting, which allowed them to store and consume food over extended periods.

In essence, the eating habits of Homo sapiens reflect our species’ ability to adapt, innovate, and thrive in diverse environments. From humble beginnings as hunter-gatherers to the sophisticated food systems of today, our dietary evolution mirrors the complex interplay between biology, culture, and technology that defines us as humans. By understanding the journey of our ancestors and the development of our foodways, we gain valuable insights into the forces that have shaped human history and continue to influence our lives today.

Moreover, the development of agriculture and food processing technologies laid the foundation for the emergence of complex cuisines, culinary traditions, and cultural practices. Food became not only a source of sustenance but also a means of socializing, celebrating, and expressing cultural identity. The cultivation of crops and the domestication of animals fostered trade networks, cultural exchange, and the rise of urban centers, further shaping human societies and civilizations.

This exploitation of new environments draws its natural roots in agriculture. As the ability of the local geography to sustain larger populations was reached, Homo sapiens naturally migrated in groups to areas of new opportunity.

Agriculture and the Drive for Migration Across the Planet

The evolution from pre-human Australopithecus to modern man tells a tale of survival and adaptability, perseverance and growth. Humanity’s discovery of agriculture transformed it’s way of life. 

Small communities of people foraged and hunted, sustaining themselves upon the land and what it could provide. As their population grew, so did their ambitions. But as the fertile land began to dwindle, they looked beyond the horizon for new opportunities. 

Somewhere between 100,000 and 60,000 years ago, explorers and migrants set forth, driven by the promise of untouched lands ripe for cultivation.

Human migration and agriculture.

Across deserts, over mountains, and across seas, they ventured, carrying seeds and tools to new lands. From the Nile Delta to the Indus Valley, from the Yangtze River to the Americas, they spread, establishing settlements and cultivating crops adapted to each new environment.

Their journey was arduous, fraught with challenges and setbacks, but fueled by the vision of abundance and prosperity. Along the way, they encountered new cultures, traded knowledge, and forged alliances, shaping the course of human history.

The legacy of their journey echoes in the diversity of crops and cultures that now span the globe, a testament to the transformative power of agriculture and the indomitable spirit of humanity.

Further Reading

Atlas of Human Evolution, The Age of Australopithecus – http://atlasofhumanevolution.com/australopithecus.asp