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Question
Read the following statement and justify same in your own words with the help of suitable example.
Human evolution began approximately 7 crore years ago.
Solution 1
The dinosaurs became extinct around 7 crore years back and from that point human evolution began. Humans are thought to have evolved from monkey like animals which looked more or less like modern lemurs. These monkey like animals further evolved into ape like animals. Some of these ape like animals evolved into gibbon and orangutan while rest of them evolved into gorilla and chimpanzees. From their evolution, the first human like animal called Ramapethicus evolved. The following table lists the evolutionary history of modern man:
Year |
Evolution |
15 million years ago |
Dryopithecus (ape-like) and Ramapithecus (man-like) |
3 − 4 million years ago |
Man-like primates |
2 million years ago |
Australopithecines, also called |
1.5 million years ago |
Homo erectus |
1,50,000 years ago |
Neanderthal man |
10,000 − 75,000 years ago |
Homo sapiens |
Solution 2
- The Earth's ice age began approximately 7 crore years ago. Under these conditions, dinosaurs went extinct. Mammal evolution and variety began during this period. Because of climate change, forest cover has reduced rapidly.
- The ancestors of monkey-like animals were Lemur like animals that developed around this time.
- Around 4 crore years ago, these monkey-like creatures gradually lost their tails.
- The body and brain expanded, creating the first ape-like mammals. Monkey-like ancestors shared evolutionary connections with apes and human-like creatures.
- Human evolution was characterised by changes in brain volume, upright walking abilities, and improved hand manipulation.
- Human evolution began approximately 7 crore years ago. The true smart intelligent man evolved approximately 50,000 years ago.
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