hominid evolution: how we became human. in your opinion, what is being human? is being human being...

Hominid Evolution: Hominid Evolution: How we became HumanHow we became Human

In your opinion, what is being human?In your opinion, what is being human?

Is being human being Is being human being humane?humane?

How are we different from How are we different from other animals?other animals?

Have we always been the Have we always been the same—intellectually, same—intellectually, culturally and physically—culturally and physically—as we are today?as we are today?

What other questions do What other questions do you have about being you have about being human?human?

Da Vinci sketched human development in the womb

What is the theory of evolution?What is the theory of evolution? In biology, evolution is the In biology, evolution is the

change in the heritable traits of a change in the heritable traits of a population over successive population over successive generations, as determined by generations, as determined by genetic changes.genetic changes.

Evolution is the source of the Evolution is the source of the vast diversity of life:vast diversity of life: all all organisms are related to each organisms are related to each other through common descent other through common descent as products of evolutionary as products of evolutionary changes over billions of years. changes over billions of years.

Over time new species evolve from Over time new species evolve from existing species and other species existing species and other species become extinct, resulting in the become extinct, resulting in the ever-changing biological world ever-changing biological world reflected in the fossil record. reflected in the fossil record.

The excavation of a dinosaur spine providesan example of how some species have become extinct over time

What is the theory of hominid evolution?What is the theory of hominid evolution?

Hominid (or human) evolutionHominid (or human) evolution is the part of is the part of the theory of evolution that looks into how the theory of evolution that looks into how human beings emerged as a distinct species.human beings emerged as a distinct species.

The study of human evolution encompasses many The study of human evolution encompasses many scientific disciplines. Evidence comes from:scientific disciplines. Evidence comes from: Archaeology (this will be the power point’s focus)Archaeology (this will be the power point’s focus) Physical anthropology Physical anthropology Behavioral studies of modern primatesBehavioral studies of modern primates Genetics andGenetics and LinguisticsLinguistics

When did humans diverge from other hominids When did humans diverge from other hominids and become a separate species?and become a separate species?

10 million years ago 10 million years ago (m.y.a): Humans and other (m.y.a): Humans and other hominoidea (hominid-like hominoidea (hominid-like creatures) shared common creatures) shared common ancestorsancestors

8 m.y.a.: Humans and 8 m.y.a.: Humans and other great apes shared a other great apes shared a common ancestorcommon ancestor

5 m.y.a.: Humans and 5 m.y.a.: Humans and chimpanzees shared a chimpanzees shared a common ancestorcommon ancestor

Chimpanzees and humans are 99% genetically similar

What evidence supports hominid evolution? What evidence supports hominid evolution? Fossil evidence. Examples of where Fossil evidence. Examples of where

fossil evidence has been found:fossil evidence has been found:

What evidence supports hominid evolution?What evidence supports hominid evolution?

The oldest hominid The oldest hominid fossils date back 7 fossils date back 7 million years ago.million years ago.

Called Called Sahelanthropus Sahelanthropus tchadensis, 7 tchadensis, 7 million year old million year old skulls of this skulls of this hominid species hominid species were discovered in were discovered in Chad (Central Chad (Central Africa) in 2000.Africa) in 2000.

Sahelanthropus tchadensis skull fragments

What evidence supports hominid evolution?What evidence supports hominid evolution?

Between 4 million and 1 million years ago, Between 4 million and 1 million years ago, evidence shows that the Ardipithecus and evidence shows that the Ardipithecus and Australopithecus genuses lived in Africa. Australopithecus genuses lived in Africa.

Australopithecines were only three to five Australopithecines were only three to five feet tall. Their brain sizes were about 1/3 as feet tall. Their brain sizes were about 1/3 as big as modern humans’, but slightly larger big as modern humans’, but slightly larger than chimpanzees’ brains.than chimpanzees’ brains.

Their teeth and jaws were much larger than Their teeth and jaws were much larger than that of modern humans--much more similar that of modern humans--much more similar to that of apes.to that of apes.

However, there is not enough evidence to However, there is not enough evidence to prove that Australopithecines are the prove that Australopithecines are the precursors to the human genus Homo.precursors to the human genus Homo.

Examples of evidence:Examples of evidence: 4.4 m.y.a. 4.4 m.y.a.

Ardipithecus ramidus Ardipithecus ramidus teeth have been found teeth have been found in Ethiopia.in Ethiopia.

The teeth appear to The teeth appear to be more ape-like than be more ape-like than any other hominid.any other hominid.

Ardipithecus ramidus teeth

Examples of evidence:Examples of evidence:

The most famous and The most famous and complete complete Australopithecus Australopithecus specimen, nicknamed specimen, nicknamed “Lucy”, was excavated in “Lucy”, was excavated in Ethiopia during the Ethiopia during the 1970s. 1970s.

Lucy lived 3.18 m.y.a.. Lucy lived 3.18 m.y.a.. Her brain size was 400 - Her brain size was 400 - 500 cc… a third the size 500 cc… a third the size of modern humans.of modern humans.

Lucy’s discovery revolutionized archaeology

How do we know that How do we know that Australopithecines Australopithecines

like Lucy walked upright?like Lucy walked upright? Lucy’s anatomy:Lucy’s anatomy:

Her bowl-shaped pelvis Her bowl-shaped pelvis was weight bearingwas weight bearing

Her angled hip and knee Her angled hip and knee jointsjoints

Her S-shaped vertebrae Her S-shaped vertebrae and spineand spine

Her foramen magnum Her foramen magnum below her skullbelow her skull

Her enlarged big toe, in Her enlarged big toe, in line with her other toesline with her other toes

Footprints found at Footprints found at Laetoli, Kenya, that date Laetoli, Kenya, that date to 3.7 m.y.a.to 3.7 m.y.a.

Model of Lucy walking upright; Lucy would have walked bent-kneed more like a chimpanzee


Nicknamed “Mrs.. Ples” and “Taung Nicknamed “Mrs.. Ples” and “Taung child”, these Australopithecus africanus child”, these Australopithecus africanus skulls from South Africa date back 2.5 skulls from South Africa date back 2.5 m.y.a.. m.y.a..

Examples of evidence:Examples of evidence: The Australopithecus (left) from Ethiopia, A. garhi, dates The Australopithecus (left) from Ethiopia, A. garhi, dates

back 2.5 m.y.a.. Primitive stone tools just as old were back 2.5 m.y.a.. Primitive stone tools just as old were found at A. garhi sites, suggesting that they may have found at A. garhi sites, suggesting that they may have been the first tool makers (a very human behavior…)been the first tool makers (a very human behavior…)

The other Australopithecus (right), A. boisei, nicknamed The other Australopithecus (right), A. boisei, nicknamed “Nutcracker Man” for his big teeth, was found in “Nutcracker Man” for his big teeth, was found in Tanzania and dates 1.75 m.y.a..Tanzania and dates 1.75 m.y.a..

Who were Homo habilis?Who were Homo habilis? Also referred to as “Handy Man”, Also referred to as “Handy Man”,

Homo habilis lived between 2.5 Homo habilis lived between 2.5 and 1 m.y.a. (overlapping with and 1 m.y.a. (overlapping with Australopithecines).Australopithecines).

Their faces still looked primitive, Their faces still looked primitive, but had less projection than but had less projection than Australopithecines.Australopithecines.

H. habilis’ brains were larger H. habilis’ brains were larger and more human-like than the and more human-like than the Australopithecines. Australopithecines.

Archaeologists believe their Archaeologists believe their larger brain size and power led larger brain size and power led H. habilis to be the first to speak H. habilis to be the first to speak - and to make and use stone tools - and to make and use stone tools (one of the fundamental features (one of the fundamental features of modern humans).of modern humans).

Their validity, however, as our Their validity, however, as our direct ancestor is questioned.direct ancestor is questioned.

Homo habilis was the first member of our genus

A review of early hominid evolution:A review of early hominid evolution:

Sahelanthropus tchadensis(7.0 m.y.a.)

From the common human - From the common human - chimpanzee ancestor to Homo chimpanzee ancestor to Homo

erectuserectus

Who were Homo Erectus?Who were Homo Erectus? Also called upright Also called upright

man, Homo erectus man, Homo erectus lived between 2.5 lived between 2.5 million and 1 million and 1 m.y.a.. Like us, m.y.a.. Like us, they lived in the they lived in the Neolithic Era.Neolithic Era.

Homo erectus had Homo erectus had larger bodies and larger bodies and brains than H. brains than H. habilis. Physically habilis. Physically Homo erectus had Homo erectus had a protruding jaw, a protruding jaw, thick brow ridge thick brow ridge and a long, low and a long, low skull.skull.

Homo erectus is probably our direct ancestor

What is the importance of a bigger What is the importance of a bigger body and brain?body and brain?

Homo erectus’ larger bodies required more Homo erectus’ larger bodies required more calories, but may have helped them in self-calories, but may have helped them in self-defense against predators.defense against predators.

Their larger brains correlate with more complex Their larger brains correlate with more complex stone tools. Archaeologists suspect that their stone tools. Archaeologists suspect that their larger brains led them to develop better tools larger brains led them to develop better tools than Homo habilis or the Australopithecines; as a than Homo habilis or the Australopithecines; as a result Homo erectus survived longer than the result Homo erectus survived longer than the other hominids.other hominids.

Archaeological evidence indicates that Homo Archaeological evidence indicates that Homo erectus were the first hominids to learn to control erectus were the first hominids to learn to control fire.fire.

Homo erectus were the first hominids Homo erectus were the first hominids to control fireto control fire

What can fire be used for?What can fire be used for? Fire can be used to cook Fire can be used to cook

meat and other foods. meat and other foods. Cooked foods can be Cooked foods can be chewed and swallowed chewed and swallowed quickly, thus give their quickly, thus give their eaters more energy eaters more energy (calories). This extra (calories). This extra energy enabled hominid energy enabled hominid brains to keep growing.brains to keep growing.

Fire can also be used to Fire can also be used to scare off predators. scare off predators. Animals other than Animals other than humans are afraid of fire.humans are afraid of fire.Hominids used fire to scare off predators

What can fire be used for?What can fire be used for? Lastly, fire can be used Lastly, fire can be used

to keep warm in colder to keep warm in colder environments. environments.

Homo habilis had Homo habilis had stayed in Africa, but stayed in Africa, but Homo erectus migrated Homo erectus migrated to the Middle East, to the Middle East, India, Southeastern India, Southeastern Asia, China and Asia, China and Europe.Europe.

Homo erectus were the Homo erectus were the first hominids to leave first hominids to leave Africa.Africa.

Homo erectus sites

Who were Homo Who were Homo neanderthalensis?neanderthalensis?

Also known as Neanderthals, these Also known as Neanderthals, these hominids lived in Europe and hominids lived in Europe and Southwestern Asia/the Arabian Southwestern Asia/the Arabian peninsula between 200,000 and peninsula between 200,000 and 30,000 years ago.30,000 years ago.

Neanderthals are considered either Neanderthals are considered either a variety of Homo sapiens or a a variety of Homo sapiens or a separate species.separate species.


Physically, they Physically, they stood 5’ to 5’6” stood 5’ to 5’6” tall. They were tall. They were muscular and muscular and thick boned thick boned (their bones were (their bones were 10-20% heavier 10-20% heavier than people’s than people’s today).today).The picture shows a

Neanderthal skeleton(left) next to a humanskeleton (right). Notice the density of Neanderthal bones.

Where did Homo neanderthalensis Where did Homo neanderthalensis live?live?

Who were Homo neanderthalensis?Who were Homo neanderthalensis? Neanderthals lived during Neanderthals lived during

the most recent Ice Age. the most recent Ice Age. To survive they lived in To survive they lived in caves. caves.

When no caves were When no caves were available they built available they built temporary shelters from temporary shelters from wood and animal bones.wood and animal bones.

Homo neanderthalensis Homo neanderthalensis were skillful hunters and were skillful hunters and gatherers; they made gatherers; they made stone blades, scrapers, and stone blades, scrapers, and other complex tools other complex tools designed for specific tasks.designed for specific tasks.

Caves provided Neanderthals warm shelter


Neanderthals Neanderthals attached attached importance to importance to individuals’ lives individuals’ lives and deaths.and deaths.

For example, they For example, they had burial rituals had burial rituals wherein they placed wherein they placed flowers on their flowers on their dead. They also dead. They also cared for physically cared for physically disabled members disabled members of their groups.of their groups.

Neanderthal skeletons were intentionally buried

Who were Homo neanderthalensis?Who were Homo neanderthalensis? Neanderthals Neanderthals

vanished around vanished around 30,000 years ago- why 30,000 years ago- why remains a mystery.remains a mystery.

Archaeologists think Archaeologists think that they either that they either evolved in Homo evolved in Homo sapien sapiens, or sapien sapiens, or that they were that they were replaced by our replaced by our species as we spread species as we spread throughout the world.throughout the world.

A forensic reconstruction of a Neanderthal woman

What is the latest evidence What is the latest evidence aboutabout

Hominid Evolution?Hominid Evolution? The latest evidence found over the last The latest evidence found over the last decade has changed the theory by adding in decade has changed the theory by adding in new hominid species, such as:new hominid species, such as: Kenyanthropus platyops, or Flat Face, 3 m.y.a.Kenyanthropus platyops, or Flat Face, 3 m.y.a. Paranthropus robustus, or Robustus, 2 m.y.a.Paranthropus robustus, or Robustus, 2 m.y.a. Homo heidelbergensis, or Goliath, 800,000 y.a.Homo heidelbergensis, or Goliath, 800,000 y.a. Homo floresiensis, or Hobbit, 30,000 y.a.Homo floresiensis, or Hobbit, 30,000 y.a.

The discovery of these new fossils has made The discovery of these new fossils has made us realize that there were multiple hominids us realize that there were multiple hominids alive at most times during prehistory. Only alive at most times during prehistory. Only today is there just one type of hominid—today is there just one type of hominid—Homo sapien sapiens!Homo sapien sapiens!

Who were Homo sapiens?Who were Homo sapiens? Homo sapiens, the archaic Homo sapiens, the archaic

version of our own species version of our own species Homo sapien sapiens, Homo sapien sapiens, came onto the evolutionary came onto the evolutionary scene about 500,000 y.a..scene about 500,000 y.a..

Homo sapiens’ skeleton Homo sapiens’ skeleton and teeth were less robust and teeth were less robust than earlier hominids; they than earlier hominids; they also had large brow ridges, also had large brow ridges, small foreheads and chins small foreheads and chins compared to modern compared to modern humans.humans.

Their brains were much Their brains were much bigger than earlier bigger than earlier hominids (sapiens= wise)hominids (sapiens= wise)

Archaeologist think there Archaeologist think there is a connection between is a connection between erectus and sapienserectus and sapiens

Whose skull is whose?

Who are Homo sapien Who are Homo sapien sapiens?sapiens? Anatomically modern Homo Anatomically modern Homo

sapien sapiens existed by sapien sapiens existed by 200,000 y.a.200,000 y.a.

Compared to Homo sapiens, Compared to Homo sapiens, our own species developed our own species developed a more advanced culture a more advanced culture including clothing, jewelry including clothing, jewelry and art in addition to tools.and art in addition to tools.

Our large brain size, our Our large brain size, our imagination, our abstract imagination, our abstract thinking, our tool making thinking, our tool making and our art mark us as and our art mark us as human!human!

What achievements make Homo What achievements make Homo sapiens human?sapiens human?

By 35,000 y.a. humans made cave paintings By 35,000 y.a. humans made cave paintings around the world. Archaelogists have three around the world. Archaelogists have three theories why:theories why: Magical significanceMagical significance Pictorial textbook designed to help young huntersPictorial textbook designed to help young hunters Children’s initiation rite into adulthoodChildren’s initiation rite into adulthood

Cave painting from (clockwise): Australia, Algeria and Argentina

So… what does it mean to be So… what does it mean to be human?human?

Activity: Spend a few minutes reviewing Activity: Spend a few minutes reviewing your notes. Then answer the question your notes. Then answer the question above:above: From a scientist or historian’s perspective;andFrom a scientist or historian’s perspective;and From your own perspective.From your own perspective.

After you have done so, form a group with After you have done so, form a group with two other students. two other students.

Your job is to make a cave painting as a Your job is to make a cave painting as a group that expresses visually what it means group that expresses visually what it means to be human, based on all of your ideas.to be human, based on all of your ideas.

hominid evolution: how we became human. in your opinion, what is being human? is being human being...

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