Becoming Human (3 Video Guides)

How are these latest discoveries being used to challenge traditional conceptions of human evolution

- instability of the environment- lead to human evolution need for tools -climate changed, variability was the driving force and our ancestors were adapted to change and were versatile

what makes us special

Culture makes us unique we can adapt easily can think complex exploration of the world around us climate upheavels makes us special

why is it so hard to obtain samples of ancient DNA

DNA degrades steadily overtime only leaving fragments

what kinds of "big questions" can be answered with a nearly complete ancient skeleton?

How old was he? (skeleton- growth plates fused or not) did the boy grow up like a human or ape?

what was the climate of Africa like roughly 3 million years ago to 1.5 million years ago?

Series of cycling lakes, constant turnover and change started very dry then started cycling wet/dry this is where tools evolved

when did homo erectus leave Africa and why?

about 2 mya left Africa to find more food also the climate shifted, spreading grasslands and lack of animals to hunt

what are the effects of homo sapiens on large animal communities

arrival of Homo sapiens coincides with the vanishment of large animal communities in the area

what is thought to explain the evolution of what we now recognize as social structure

building fires and cooking drawn to a common place, the fireplace waiting for food to cook, creating a social environment

What is the Molecular Clock and how does it work?

can compare DNA between related species to see how related they are and when they split -can calculate how long ago the species shared a common ancestor with DNA

what does the hand axe made of pink quartz found in the "pit of bones" suggest about human thought complexity? what do archaeologists think that their mental processes were capable of

capable of symbolism and belief, and maybe planning

What is the significance of the discovery of a fossil named "Selam" (or "peace" Ethiopian)?

child from the dawn of human evolution

what are the hidden costs of large brains?

consume 25% of body energy need lots of calories to feed the brain

What was the climate/environment of Africa like many millions of years ago? (6 mya)

covered in water, wet tropical environment covered in rainforests, lakes, forests, and woodlands

What can we tell about the lunate sulcus from Selam's skull? Why is this important?

deep furrow in the brain- vision and complex thought neuro complex was bigger - more thought

How large was the brain of Homo habilis? Why after millions of years of stasis, did brain capacity suddenly increase with Homo Habilis?

doubling of the brain value (800 cc) increase in cognitive ability has forehead, expanded frontal regions

what is "persistence hunting"

exhausting an animals to have a heat stroke the animals cannot sweat whereas humans can

What is Homo floresiensis (or The Hobbit)?

exhibit island dwarfism population evolved from Homo erectus tiny size, 400 cc brain

what is significant about the cave found deep inside an archaeological site in Spain? what did archaeologists discover there?

exposed ancient human habitation and oldest remains in "the pit of bones" and an extensive labyrinth full of many complete skeletons

what two major climate changes affected the evolutionary course of Homo sapiens in Africa>

glacial stage- vast ice sheets, mega drought in Africa

What is the "great rift valley" and why is it important

hot bed of tectonic activity, ancient layers exposed showing environmental change, this was a catalyst for our evolution need more adaptable ancestors

What is the significance of the FOXP2 gene? Do Neanderthals possess this gene

involved in speech development Neanderthals has this gene

how similar are modern humans at the DNA level? why so little genetic diversity? what is the phenomenon called and what lead to it?

lack of diversity bc we lost this diversity 99.9% little genetic diversity bottle neck effect from the major climate changes

What evidence is used to suggest that brain development was happening in early human ancestors?

length of childhood humans-2 decades to mature apes/chimps- 3-4 years

how can paleoarchaeologists tell what the diet of ancient hominins was?

look at bones and teeth

what clues tell us turkana boy's species probably had less hair than apes do today?

looking at the louse 2 different types of lice( due to apes and gorillas colonizing) lost body hair in order to cool the body better

in what ways are stone tools indicative of an increase in the "thinking power" of Homo erectus?

marks the birth technology and inventions of Homo erectus - tools allow Homo erectus to get food and making decisions in using the rocks to make the tools

of all ancient humans which hominin most closely resembles us

neanderthals

has evolution stopped

no

What does Turkana boy represent in terms of human evolutionary history?

not fully human but not an ape

what examples of early art were found at blombos cave>

ochre was found in the Blombos Cave cross hatch patter and shells with holes drilled in them for necklaces

which two parts of the Neanderthal brain reduced in size? What does this signify

parietal and temporal lobe low and elongated brain this reduced size signifies limited thinking power

who is probably common ancestor of both Neanderthals and Homo sapiens

people that left Africa 0.5 mya - Homo heidelbergensis

What is one example of a technology that Homo sapiens used to help them survive

projectile weapons

what is the benefit of humans extended childhood?

related the brain size, brain has to grow and learn how to function

According to biochemist Daniel Lieberman, why did human ancestors become bipedal?

saved energy walking on two legs, cool more efficiently, had to go farther to get food, needed to save energy

What are notable characteristics of the Homo erectus head compared to modern humans?

slightly smaller brain, slightly bigger jaw

what is a possible scenario for the death of "turkana boy"?

started his day on a hunt, was sick and in pain, infection in his jaw, lots of pain because infection was spreading though his body ultimately killed him may have died in water or near water based on how the body was preserved

What clues tells us turkana boy was in fact a "boy" and not an adult? How old do they estimate him to have been at death?

the rods in the tooth, in the enamel, help represent 1 day's growth He was 8 years old

why was hunting so dangerous for the Neanderthals?

they didn't have throwing spears and arrows they had to get close to their prey to kill

what appeared in the fossil record about 2 million years ago that marked the "dawn of a new era" a significant step in human evolutionary history?

tools- rock broken into tools

what specimen gave us the first nearly complete hominid skeleton? what is its species?

turkana boy- homo erectus

What were the first stone tools? How can paleoarchaeologists tell that aren't just stones?

very sharp edges, tools are preserved clear cut marks in fossils of animals- meat was in their diet

What are the comparisons made between chimpanzees and Australopithecus and how are they significant?

walked upright, pelvis(the orientation of the bones do not resemble an ape)

what physical characteristics are associated with the transition from ape to homo

walking on two legs, lower forehead, bigger brain capacity

When did homo erectus evolve

2 mya

Roughly when was Selam living and how do we know this?

3.3 million years ago, due to volcanic ash

How old is the fossil known as Sahlenthropus tchadensis (named Toumai)? What is the (potential) significance of this fossil

6 million years ago Was this creature a human ancestor? Did this creature walk on 2 legs before Selam and Lucy?

How can paleoneurologists draw conclusions about brain structures if the brain is not preserved in the fossil record?

Based on the cast of a brain case we can tell things about the brain- indications testing for formations and depressions

what was the first hominin species to migrate to Europe?

Homo erectus

why were Neanderthals struggling to survive

Humans pushed Neanderthals out -wild climate changes in Europe - had a big brain that needed lots of energy