advantages and disadvantages of cigarettes

advantages of cigarettes
smoking helps to avoid knee pain and knee sugery.
smoking helps to reduce cold.
smoking helps to avoid parkinson's disease.
smoking helps to reduce obisity.
smoking gives relasation to our mind

disadvantages of cigarettes
smoking causes cancer.
smoking causes heart disease.
smoking causes breathing problem.
smoking allows carbon monoxide enter our body.
smoking causes strokes.

Ancient americans

The Maya and aztecs of central Americans and the incas of peru developed the remarkable cultures that were swept away by spanish invaders in the 1500's.They were the final witnesses to the long history of  human civilization in ancient americe. 

How fossils are formed

For a dead animal to become fossile it need to be buried quickly.By falling into muddy water bed or by  strom etc.

The soft tissue of the animal rots away but the skeleton remains and turn into rocks after millions of years 

Over time the mud and river sediments build up over the fossils and form into sedimentary rocks

Because of erosion and movements in the Earth's crust can expose it.A Palaeontologist can find it easily

 

PALAEONTOLOGIST - a person who study about rocks,fossils and prehistory