The evolution of man may not be true. But the mother Earth pampered unbelievably huge or enormously massive species million years ago that is undeniable fact based on the carcass findings and what went under the earth crust for million of years and the traces of which were found by the men afterwards. Following are some of the species whose traces have been found by scientists:
Diatryma Large Flightless Bird- Carnivorous
Arthropleura
Eight and a half foot long bug lived 300 million years ago.
Ceratogaulus Rhinoceros
Chalicotherium
Dunkleosteus
Existed 50 million years ago and was 30 feet long weighed around 4 tons.
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Gigantopithecus
Imagine what inspired King Kong producers? They were about 10 feet long and weighed around 1000 pounds.
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Jaekelopterus Rhenaniae
This Ocean Scorpion existed 390 million years ago was 8 feet long. 
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Macrauchenia
The most famous discovery of Charles Darwin existed about 20000 years ago.
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Brontosaurus aka Mamenchisaurus
Existed almost 150 million years ago had neck as long as 46 feet and made around 50% of the total body length.
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Mao
The giant flightless birds of New Zealand existed around 1500 A.D.were 12 feet in height and weighed around 500 pounds.
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Pliosaur
These ocean hunters were 52 feet long.
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Procoptodon Goliah
Existed 18000 years ago was 10 feet tall and weighed around 500 pounds.
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Titanoboa
Existed 58 million years ago was almost 50 feet long and weighed 2500 pounds.
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Whorl Sharks
Existed 300 million years ago
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