The building of temples and great cities without modern machinery, using astronomy to predict astrological cycles and plant crops and using their language to communicate and measure time are some of the Mayans most notable achievements.<span> During a 600-year period of time, which was from 300 A.D. until 900 A.D., the Mayans made many great achievements in science, communications, engineering and agriculture.</span>
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the West Indies</span>
The two discoveries that brought a revolution in early man's life are:
1) Agriculture - It helped the early man to produce its own food. this innovation made possible new flux of innovations and ideas the husbandry and domestication of all modern cattle and pets (except dogs), the formation of soldiers and wars, the money, the origin of religion, writing and all the very basis of modern life. Developing all these new outcomes would be impossible without the cooperation and organized structure of agricultural societies.
2) Language and paintings - Language helps them to communicate with each other and painting which they did at that time helped Historians today to know about their life, language, etc.