The 4th millennium BC spanned the years 4000 BC to 3001 BC. Some of the major changes in human culture during this time included the beginning of the Bronze Age and the invention of writing, which played a major role in starting recorded history. The city states of Sumer and the kingdom of Egypt were established and grew to prominence. Agriculture spread widely across Eurasia. World population growth relaxed after the burst that came about from the Neolithic Revolution. World population was largely stable in this time at roughly 50 million with a slow overall growth rate at roughly 0.03% p.a. Culture Near East Mesopotamia 4100–3100 BC – the Uruk period, with emerging Sumerian hegemony and development of "proto-cuneiform" writing; base-60 mathematics, astronomy and astrology, civil law, complex hydrology, the sailboat, potter's wheel and wheel; the Chalcolithic proceeds into the Early Bronze Age. 3500–2340 BC – Sumer: wheeled carts, potter's wheel, White Temple ziggurat, bronze tools and weapons. First to Fourth dynasty of Kish in Mesopotamia. Sumerian temple of Janna at Eridu erected. Temple at Al-Ubaid and tomb of Mes-Kalam-Dug built near Ur, Chaldea. 3000 BC – Tin is in use in Mesopotamia soon after this time. 3500–2340 BC – First cities developed in Southern Mesopotamia. Inhabitants migrated from north. The cuneiform script proper emerges from pictographic proto-writing in the later 4th millennium. Mesopotamia's "proto-literate" period spans the 35th to 32nd centuries BC. The first documents unequivocally written in the Sumerian language date to the 31st century BC, found at Jemdet Nasr. Dams, canals, stone sculptures using inclined plane and lever in Sumer. Urkesh (northern Syria) founded during the fourth millennium BC possibly by the Hurrians. The Courtyard is introduced to Mesopotamia. Persian plateau 4000 BC – Susa is a center of pottery production. c. 4000 BC – Beaker from Susa (modern Shush, Iran) is made. It is now at Musée du Louvre, Paris. Proto-Elamite from 3200 BC. Anatolia and Caucasus c. 3700 BC to 3000 BC – The Maykop culture of the Caucasus, contemporary to the Kurgan culture, is a candidate for the origin of Bronze production and thus the Bronze Age. 3400–2000 BC – Kura-Araxes: earliest evidence found on the Ararat plain. Egypt 4000–3000 BC – Naqada culture on the Nile. First hieroglyphs appear thus far around 3500 BC as found on labels in a ruler's tomb at Abydos. Predynastic pharaohs Tiu, Thesh, Hsekiu, Wazner, Ro, Serket, Narmer.