fossil evidence for human evolotion Flashcards
(15 cards)
What common ancestor did humans and chimpanzees evolve from?
A common ancestor that existed around 6 million years ago
This ancestor is part of the evolutionary lineage shared by humans and chimpanzees.
What are human beings and their ancestors collectively known as?
Hominids
Hominids include all species on the human side of the evolutionary tree, including extinct relatives.
What characteristics do hominid fossils exhibit?
Characteristics that are between apes and humans
These characteristics provide insights into the evolutionary process from ape-like ancestors to modern humans.
How old is the fossil known as ‘Ardi’?
4.4 million years old
Ardi is a fossil of the species Ardipithecus ramidus, found in Ethiopia.
What features of Ardi suggest she climbed trees?
She had an ape-like big toe to grasp branches
This feature indicates adaptations for climbing, similar to modern apes.
What does the structure of Ardi’s legs suggest?
She walked upright like a human
This indicates a transitional form between tree-dwelling apes and bipedal humans.
What is the cranial capacity?
The space taken up by the brain in the skull
It is a measure used to estimate brain size in fossil hominids.
How old is the fossil known as ‘Lucy’?
3.2 million years old
Lucy is a fossil of the species Australopithecus afarensis, also found in Ethiopia.
What adaptation do Lucy’s feet suggest?
More adapted to walking than climbing
Lucy’s feet lacked an ape-like big toe, indicating a shift towards bipedalism.
What is the significance of the leg and foot structure in Lucy?
She walked upright more efficiently than Ardi
This reflects further advancement in bipedal locomotion among hominids.
Who organized an expedition to look for hominid fossils in 1984?
Richard Leakey
Leakey’s team made significant discoveries that contributed to understanding human evolution.
What is ‘Turkana Boy’?
A 1.6 million year old fossil skeleton of the species Homo erectus
Turkana Boy shows a mixture of human and ape-like features but is more human-like than earlier fossils.
What features of Turkana Boy are more human-like?
Short arms and long legs
These features indicate a further adaptation to bipedalism compared to earlier hominids.
What does Turkana Boy’s brain size resemble?
Similar to human brain size
This suggests a significant evolutionary advancement in brain development.
What does the structure of Turkana Boy’s legs and feet indicate?
He was better adapted to walking upright than Lucy
This highlights the progression of bipedalism in human evolution.
