Final Exam: Origins of Humans Flashcards
a mammal group including monkeys, apes, and lemurs
primates
What 3 features do humans share with other primates?
- Opposable thumbs
- Larger brains compared to other mammals
- Can make and use tools
What kinds of climates do non-human primates usually live in?
Warm climates
How did climate change through the Cenozoic create problems for primates?
During the Ice Age time, their territory decreased because of the cold (we had fire so we weren’t as limited as they were to space back then)
Humans are what 4 things? Why?
- Vertebrates (we have backbones)
- Tetrapods (we have four limbs, lungs)
- Mammals (feed their young milk, have 3 middle ear bones, and one lower jaw bone)
- Primates (opposable thumbs and large brains)
time range of human-like fossil species
Late in the Neogene– Quaternary
The amount of _______ cover back then was much smaller, so primates were limited to smaller spaces.
forestland
Human-like fossils were first found where?
In the East African Rift Valley
An area of active plate tectonics and immature sediment being deposited. Super famous, highly studied area.
East African Rift Valley
two-legged primates
bipedal
Walking on two legs appeared (before/after) large brain size appeared
before
What is special about Australopithecus that shows that it is an ancestor of humans?
They were bipedal, had legs and feet much like humans, and walked standing straight up.
What kind of environment did Australopithecus live in?
Grasslands (Eastern and South Africa)
How would walking on two legs be advantageous for survival in grasslands? (3)
- Walking
- Seeing predators
- Carrying food
What is the scientific name for humans?
Homo sapiens
T or F: There used to be a lot of different homo species that existed at the same time. Now only homo sapiens are left.
True
The evolution of humans includes (larger/smaller) brain size, (larger/smaller) jaw bone, and _____ tools.
larger; smaller; stone
On what continent did humans and human-like species originate?
(East) Africa
Humans mostly moved what direction at first? What is a probable reason for this?
Mostly moved east west, probably bc of warmer climates
Humans spread to what place last?
America
Homo ______ had moved out of Africa before Homo sapiens.
erectus
Why was it easier to reach North America during the Ice Age than it is today?
Low sea level created a land connection
What are Neanderthals?
Relatives of humans (like cavemen)
Neanderthals had (longer/shorter), (thinner/thicker) bones and often showed signs of _____ _______.
shorter, thicker; bone injuries
Why do many scientists now consider Neanderthals to be members of our own species?
DNA Evidence shows breeding of humans and neanderthals (= same species?)
T or F: Neanderthals had a behavior of caring for each other (digging graves) → more complex human like behaviors
true
T or F: Neanderthals went extinct when humans met neanderthals, although there is no clear evidence of why.
True
What happened to other human-like species as humans (Homo sapiens) spread around the world?
They went extinct
The world-wide phenomenon if megafauna going extinct all over the world mysteriously doesn’t affect what two places? What is the evidence of this?
- Africa and Southern Asia
- Evidence: still have elephants, etc there
What are the 2 things that make the megafauna extinction unique?
- Happened at different times in different places
- Only large land animals go extinct
What are the 2 hypotheses for why the Ice Age megafauna went extinct?
- Warming climate at the end of the last glacial (it warmed up, things died out)
- Humans overhunted prey that were not used to human predators (The “Overkill” Hypothesis)
What are the 2 problems with the warming climate hypothesis?
- Different times on different continents (ex: Australia megafauna went extinct before North America; Australia was still cold at this time)
- Megafauna had survived previous interglacials
What is the strength of the “Overkill” Hypothesis? Problem of this hypothesis?
- Strength: explains extinction of large animals (slow breeders; slow to reproduce)
- Problem: Timing may or may not line up
If overhunting by humans killed off the mammoths, what should we see in the fossil record?
Mammoths disappear soon after humans arrive.
T or F: The “Overkill” Hypothesis only works if extinction is clearly dated to soon after humans arrived.
True
What was another possible human impact that could’ve been a reason for animals being killed?
Fire use (setting woods on fire to drive animals out, then kill them)
