Early Astronomy As surviving records and artifacts make abundantly clear, many early cultures took a keen interest in the changing nighttime sky. But unlike today, the major drivin...

Life in an Estuary An estuary is the wide part of a river where it flows into the sea. It is affected by both marine influences(tides, waves, and the influx of saline water) and ri...

The Greek City-States: Sparta and Athens Of the hundreds of city-states that evolved during the Archaic Age, (800- 479 B.C.), Sparta and Athens stand out for their vividly contras...

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