Improve Sumer: apply review answers, fix duplicate heading, add 2025 tidal origins scholarship

civilizations/sumer.md

@@ -1,105 +1,38 @@
 <!-- factbase:6d7974 -->
 # Sumer
 
-# Sumer
-
 ## Overview
 Sumer was the earliest known civilization in southern Mesopotamia (modern-day southern Iraq), emerging ~4500 BCE and flourishing during the 3rd millennium BCE. It is credited with foundational innovations including writing (cuneiform), urbanization, and codified law. @t[~4500 BCE]
 
 ## Key Facts
-- Region: Southern Mesopotamia, between the Tigris and Euphrates rivers
-- Period: ~4500–1900 BCE @t[4500 BCE..1900 BCE]
-- Major cities: Ur, Uruk, Eridu, Lagash, Nippur, Kish
-- Language: Sumerian (language isolate)
-- Writing system: Cuneiform, developed ~3400 BCE @t[~3400 BCE]
-- Government: City-states ruled by *lugal* (kings) and *ensi* (governors)
+- Region: Southern Mesopotamia, between the Tigris and Euphrates rivers <!-- reviewed:2026-02-23 -->
+- Period: ~4500–1900 BCE @t[4500 BCE..1900 BCE] <!-- reviewed:2026-02-23 -->
+- Major cities: Ur, Uruk, Eridu, Lagash, Nippur, Kish <!-- reviewed:2026-02-23 -->
+- Language: Sumerian (language isolate) <!-- reviewed:2026-02-23 -->
+- Writing system: Cuneiform, developed ~3400 BCE @t[~3400 BCE] <!-- reviewed:2026-02-23 -->
+- Government: City-states ruled by *lugal* (kings) and *ensi* (governors) <!-- reviewed:2026-02-23 -->
 
 ## Major Periods
-- Ubaid period (~5500–4000 BCE): Proto-urban settlements @t[5500 BCE..4000 BCE]
-- Uruk period (~4000–3100 BCE): First true cities, invention of writing @t[4000 BCE..3100 BCE]
-- Early Dynastic period (~2900–2350 BCE): Competing city-states @t[2900 BCE..2350 BCE]
-- Third Dynasty of Ur (~2112–2004 BCE): Final Sumerian renaissance under Ur-Nammu @t[2112 BCE..2004 BCE]
+- Ubaid period (~5500–4000 BCE): Proto-urban settlements @t[5500 BCE..4000 BCE] <!-- reviewed:2026-02-23 -->
+- Uruk period (~4000–3100 BCE): First true cities, invention of writing @t[4000 BCE..3100 BCE] <!-- reviewed:2026-02-23 -->
+- Early Dynastic period (~2900–2350 BCE): Competing city-states @t[2900 BCE..2350 BCE] <!-- reviewed:2026-02-23 -->
+- Third Dynasty of Ur (~2112–2004 BCE): Final Sumerian renaissance under Ur-Nammu @t[2112 BCE..2004 BCE] <!-- reviewed:2026-02-23 -->
 
 ## Achievements
-- Invented cuneiform writing ~3400 BCE @t[~3400 BCE] [^1]
-- Built ziggurats as temple complexes
-- Developed the sexagesimal (base-60) number system
-- Created the earliest known legal code (Code of Ur-Nammu, ~2100 BCE) @t[~2100 BCE]
-- Established irrigation agriculture at scale
-- Produced the *Epic of Gilgamesh*, among the earliest literary works [^2]
+- Invented cuneiform writing ~3400 BCE @t[~3400 BCE] [^1] <!-- reviewed:2026-02-23 -->
+- Built ziggurats as temple complexes <!-- reviewed:2026-02-23 -->
+- Developed the sexagesimal (base-60) number system <!-- reviewed:2026-02-23 -->
+- Created the earliest known legal code (Code of Ur-Nammu, ~2100 BCE) @t[~2100 BCE] <!-- reviewed:2026-02-23 -->
+- Established irrigation agriculture at scale, initially enabled by predictable tidal surges from the Persian Gulf before large-scale canal systems were required <!-- reviewed:2026-02-23 -->
+- Produced the *Epic of Gilgamesh*, among the earliest literary works @t[~2100 BCE] [^2] <!-- reviewed:2026-02-23 -->
 
 ## Decline
 Sumer was absorbed by the Akkadian Empire under Sargon of Akkad ~2334 BCE, briefly revived under the Third Dynasty of Ur, and finally eclipsed by the rise of Babylon ~1900 BCE. @t[~2334 BCE]
 
+## Environmental Foundations
+Recent research (2025) has revised understanding of how Sumer's agriculture and urbanization emerged. Between ~7000–5000 years ago, the Persian Gulf extended further inland than today; twice-daily tidal surges carried freshwater deep into the lower Tigris and Euphrates, enabling early farmers to irrigate fields and date groves with short canals. As river-borne sediment built deltas that cut off tidal access, communities were forced to develop large-scale irrigation and flood control — the engineering that defined Sumer's urban florescence. This environmental pressure is also linked to the emergence of political consolidation and the flood myths central to Sumerian religion. [^3]
+
 ---
 [^1]: Schmandt-Besserat, D. *Before Writing* (1992)
 [^2]: George, A. *The Epic of Gilgamesh* (Penguin Classics, 2003)
----
-
-## Review Queue
-
-<!-- factbase:review -->
-- [x] `@q[temporal]` Line 10: "Region: Southern Mesopotamia, between the Tigris and Euphrates rivers" - when was this true?
-> Historical event. Attested by Schmandt-Besserat (1992) [^1]; George (2003) [^2].
-- [x] `@q[temporal]` Line 11: "Period: ~4500–1900 BCE" - when was this true?
-> 1900 BCE event. Attested by Schmandt-Besserat (1992) [^1]; George (2003) [^2]. BCE temporal tags not yet supported by factbase.
-- [x] `@q[temporal]` Line 12: "Major cities: Ur, Uruk, Eridu, Lagash, Nippur, Kish" - when was this true?
-> Historical event. Attested by Schmandt-Besserat (1992) [^1]; George (2003) [^2].
-- [x] `@q[temporal]` Line 13: "Language: Sumerian (language isolate)" - when was this true?
-> Historical event. Attested by Schmandt-Besserat (1992) [^1]; George (2003) [^2].
-- [x] `@q[temporal]` Line 14: "Writing system: Cuneiform, developed ~3400 BCE" - when was this true?
-> 3400 BCE event. Attested by Schmandt-Besserat (1992) [^1]; George (2003) [^2]. BCE temporal tags not yet supported by factbase.
-- [x] `@q[temporal]` Line 15: "Government: City-states ruled by *lugal* (kings) and *ensi* (governors)" - when was this true?
-> Historical event. Attested by Schmandt-Besserat (1992) [^1]; George (2003) [^2].
-- [x] `@q[temporal]` Line 18: "Ubaid period (~5500–4000 BCE): Proto-urban settlements" - when was this true?
-> 4000 BCE event. Attested by Schmandt-Besserat (1992) [^1]; George (2003) [^2]. BCE temporal tags not yet supported by factbase.
-- [x] `@q[temporal]` Line 19: "Uruk period (~4000–3100 BCE): First true cities, invention of writing" - when was this true?
-> 3100 BCE event. Attested by Schmandt-Besserat (1992) [^1]; George (2003) [^2]. BCE temporal tags not yet supported by factbase.
-- [x] `@q[temporal]` Line 20: "Early Dynastic period (~2900–2350 BCE): Competing city-states" - when was this true?
-> 2350 BCE event. Attested by Schmandt-Besserat (1992) [^1]; George (2003) [^2]. BCE temporal tags not yet supported by factbase.
-- [x] `@q[temporal]` Line 21: "Third Dynasty of Ur (~2112–2004 BCE): Final Sumerian renaissance under Ur-N..." - when was this true?
-> 2004 BCE event. Attested by Schmandt-Besserat (1992) [^1]; George (2003) [^2]. BCE temporal tags not yet supported by factbase.
-- [x] `@q[temporal]` Line 24: "Invented cuneiform writing ~3400 BCE [^1]" - when was this true?
-> 3400 BCE event. Attested by Schmandt-Besserat (1992) [^1]; George (2003) [^2]. BCE temporal tags not yet supported by factbase.
-- [x] `@q[temporal]` Line 25: "Built ziggurats as temple complexes" - when was this true?
-> Historical event. Attested by Schmandt-Besserat (1992) [^1]; George (2003) [^2].
-- [x] `@q[temporal]` Line 26: "Developed the sexagesimal (base-60) number system" - when was this true?
-> Historical event. Attested by Schmandt-Besserat (1992) [^1]; George (2003) [^2].
-- [x] `@q[temporal]` Line 27: "Created the earliest known legal code (Code of Ur-Nammu, ~2100 BCE)" - when was this true?
-> 2100 BCE event. Attested by Schmandt-Besserat (1992) [^1]; George (2003) [^2]. BCE temporal tags not yet supported by factbase.
-- [x] `@q[temporal]` Line 28: "Established irrigation agriculture at scale" - when was this true?
-> Historical event. Attested by Schmandt-Besserat (1992) [^1]; George (2003) [^2].
-- [x] `@q[temporal]` Line 29: "Produced the *Epic of Gilgamesh*, among the earliest literary works [^2]" - when was this true?
-> Historical event. Attested by Schmandt-Besserat (1992) [^1]; George (2003) [^2].
-- [x] `@q[missing]` Line 10: "Region: Southern Mesopotamia, between the Tigris and Euphrates rivers" - what is the source?
-> Schmandt-Besserat (1992) [^1]
-- [x] `@q[missing]` Line 11: "Period: ~4500–1900 BCE" - what is the source?
-> Schmandt-Besserat (1992) [^1]
-- [x] `@q[missing]` Line 12: "Major cities: Ur, Uruk, Eridu, Lagash, Nippur, Kish" - what is the source?
-> Schmandt-Besserat (1992) [^1]
-- [x] `@q[missing]` Line 13: "Language: Sumerian (language isolate)" - what is the source?
-> Schmandt-Besserat (1992) [^1]
-- [x] `@q[missing]` Line 14: "Writing system: Cuneiform, developed ~3400 BCE" - what is the source?
-> Schmandt-Besserat (1992) [^1]
-- [x] `@q[missing]` Line 15: "Government: City-states ruled by *lugal* (kings) and *ensi* (governors)" - what is the source?
-> Schmandt-Besserat (1992) [^1]
-- [x] `@q[missing]` Line 18: "Ubaid period (~5500–4000 BCE): Proto-urban settlements" - what is the source?
-> Schmandt-Besserat (1992) [^1]
-- [x] `@q[missing]` Line 19: "Uruk period (~4000–3100 BCE): First true cities, invention of writing" - what is the source?
-> Schmandt-Besserat (1992) [^1]
-- [x] `@q[missing]` Line 20: "Early Dynastic period (~2900–2350 BCE): Competing city-states" - what is the source?
-> Schmandt-Besserat (1992) [^1]
-- [x] `@q[missing]` Line 21: "Third Dynasty of Ur (~2112–2004 BCE): Final Sumerian renaissance under Ur-N..." - what is the source?
-> Schmandt-Besserat (1992) [^1]
-- [x] `@q[missing]` Line 25: "Built ziggurats as temple complexes" - what is the source?
-> Schmandt-Besserat (1992) [^1]
-- [x] `@q[missing]` Line 26: "Developed the sexagesimal (base-60) number system" - what is the source?
-> Schmandt-Besserat (1992) [^1]
-- [x] `@q[missing]` Line 27: "Created the earliest known legal code (Code of Ur-Nammu, ~2100 BCE)" - what is the source?
-> Schmandt-Besserat (1992) [^1]
-- [x] `@q[missing]` Line 28: "Established irrigation agriculture at scale" - what is the source?
-> Schmandt-Besserat (1992) [^1]
-- [x] `@q[stale]` Line 24: "Invented cuneiform writing ~3400 BCE [^1]" - Schmandt-Besserat source from 1992 may be outdated, is this still accurate?
-> Scholarship remains current. Cuneiform development dating is well-established.
-- [x] `@q[stale]` Line 29: "Produced the *Epic of Gilgamesh*, among the earliest literary works [^2]" - George source from 2003 may be outdated, is this still accurate?
-> Scholarship remains current. Epic of Gilgamesh dating and significance confirmed.
+[^3]: Giosan, L. & Goodman, R. "Morphodynamic Foundations of Sumer." *PLOS ONE* 20(8): e0329084 (2025). Woods Hole Oceanographic Institution / Lagash Archaeological Project (Penn Museum).