In this article we will discuss about the evolution of plants and animals.
Evolution of Plants:
The first organism that existed on land were plants that occur before animals or other life forms:
(i) Bryophytes were the first plant to colonies lands and were evolved before the vascular plants like pteridophytes and gymnosperms.
(ii) Vascular plants first originated in Silurian period.
(iii) Existence of sea weeds and few plants were reported around 320 mya.
(iv) Herbaceous lycopods and arborescent lycopods evolved from Zosterophyllum of Palaeozoic era.
(v) Psilophyton is the common ancestor for horsetails, ferns and gymnosperms.
Evolution of Animals:
There were plenty of plants when animals came to land. Origin of vertebrates took place in ovido vician periods. Evolution of animals occurred around 500 mya.
(i) First animals were invertebrates.
(ii) Jawless fish and amphibious fish originated around 350 mya.
(iii) The first amphibians and ancestors of modern day frogs were lobefins (Coelacanth).
(iv) Reptiles dominated the earth, around 200 mya.
(v) Land reptiles were dinosaurs of which Tyrannosaurus (about 20 feet in height) was biggest. They disappeared around 65 mya.
(vi) In Jurassic period, the first mammal shrews were evolved.
(vii) Mammals were viviparous and protected their unborn young inside the mother’s body.
(viii) When reptiles came down, mammals took over the earth.
Origin and Evolution of Man:
The fossil evidence clearly indicates that origin of man occurred in central Asia, china, Jana and India (shivalik hills).
(i) The common ancestor of apes and man is a primate Dryopithecus. The next stage was Ramapithecus in the hominid evolution.
(ii) Both were hairy and walked like gorillas and chimpanzees. Ramapithecus was more like man and was the fore-runner of hominid evolution but Dryopithecus was more ape-like.
