4th millennium BC  

From The Art and Popular Culture Encyclopedia

Jump to: navigation, search

Related e



The 4th millennium BC saw major changes in human culture. It marks the beginning of the Bronze Age and of writing.

The city states of Sumer and the kingdom of Egypt are established and grow to prominence. Agriculture spreads widely across Eurasia. World population in the course of the millennium doubles, approximately from 7 to 14 million people.




Environmental changes

Based on studies by glaciologist Lonnie Thompson (professor at Ohio State University and researcher with the Byrd Polar Research Center) [1] a number of indicators shows there was a global change in climate 5,200 years ago, Which was most probably due to a drop in Solar energy output as hypothesized by Ohio State University[2] and not due to Tollmann's hypothetical bolide hypothesis which was recently indirectly relied upon to explain events in RTE's Secrets of the Stones Archaeological investigation. As there is no evidence to suggest that there were any climate changing impacts or pass bys by comets during this period. Nevertheless The most popular referenced link to The Bronze age civilization extinctions and the cause being due to a comet may be comet Encke and the Taurids meteor shower.

  • Plants buried in the Quelccaya Ice Cap in the Peruvian Andes demonstrate the climate had shifted suddenly and severely to capture the plants and preserve them until now.
  • A man trapped in an Alpine glacier ("Ötzi the Iceman") is frozen until his discovery in 1991.
  • Tree rings from Ireland and England show this was their driest period.
  • Ice core records showing the ratio of two oxygen isotopes retrieved from the ice fields atop Africa’s Mount Kilimanjaro, a proxy for atmospheric temperature at the time snow fell.
  • Major changes in plant pollen uncovered from lakebed cores in South America.
  • Record lowest levels of methane retrieved from ice cores from Greenland and Antarctica.
  • End of the Neolithic Subpluvial, start of desertification of Sahara (35th century BC). North Africa shifts from a habitable region to a barren desert.
  • Disastrous floods in Mesopotamian region.

Significant persons

Inventions, discoveries, introductions



Unless indicated otherwise, the text in this article is either based on Wikipedia article "4th millennium BC" or another language Wikipedia page thereof used under the terms of the GNU Free Documentation License; or on research by Jahsonic and friends. See Art and Popular Culture's copyright notice.

Personal tools