(a) Name the primates that lived about 15 million years ago. List their characteristic features.
(b) (i) Where was the first man-like animal found?
(ii) Write the order in which Neanderthals, Homo habilis and Homo erectusappeared on earth.
State the brain capacity of each one of them.
(iii) When did modern Homo sapiens appear on this planet?
(a) Dryopithecus (ape-like) and Ramapithecus (man-like) were the two primates that lived 15 million years ago. These primates were hairy and their walk was similar to that of chimpanzees.
(b) (i) The first man-like animal was found in Africa.
(ii)
Year |
Evolution |
Brain capacity |
2 million years ago |
Homo habilis (Australopithecines) lived in East Africa |
650- 800 cc |
1.5 million years ago |
Homo erectus |
900 cc |
1,000 - 40,000 years ago |
Neanderthal man |
1400 cc |
(a) Select the homologous structures from the combinations given below :
(i) Forelimbs of whales and bats
(ii) Tuber of potato and sweet potato
(iii) Eyes of octopus and mammals
(iv) Thorns of Bougainvillea and tendrils of Cucurbita
(b) State the kind of evolution they represent.
Since the origin of life on the earth, there were five episodes of mass extinction of species.
(i)How is the 'Sixth Extinction', presently in progress, different from the previous episodes?
(ii)Who is mainly responsible for the 'Sixth Extinction''?
(iii)List any four points that can help to overcome this disaster.
How do homologous organs represent divergent evolution ? Explain with the help of a suitable example.