Prior to the development of navigation techniques, ancient humans had limited knowledge of the world beyond their caves. How fortunate we are that they found our future in the stars.
Our ancestors' earliest tool for finding their way in the world was the sun. Knowing where and when it rose and set gave hunters and gatherers their sense of direction and time.
Keeping track of the sun's location allowed tribes to migrate seasonally from depleted catchment areas to more bountiful ones.
Of course, the sun's utility as a compass was limited to daytime use. And to travel over water, navigational tools other than the sun were needed.
As a result, early seafarers did not stray too far from the shore. They depended on coastal navigation—using visual landmarks to chart their location—when they went out on the sea, perhaps as long as 40,000 years ago.
As civilizations came into being at the end of the Stone Age, crude lighthouses or constantly tended bonfires served as beacons to guide sea travelers back to land when night fell.
As the last Ice Age came to a close and the waters of the oceans rose, sea coasts changed. Some populations became trapped or isolated as land bridges disappeared.
In order for the human species to successfully spread out across the Earth's lands and evolve to its present diversity, a far more reliable navigational tool was required—celestial navigation, the ability to use the stars of the night as guides.
Based on direct observation, ancient cultures passed on records of the behavior of constellations, and it became known that celestial bodies followed rhythmic patterns within specific timeframes.
From the builders of the megalithic structures of Carnac in Brittany circa 4500 B.C. to the architects of Stonehenge in England circa 3000 B.C., the fledgling science of Astronomy served as an inspiration even as it provided a boost to the ability to travel by sea.
The Phoenicians of the West and the ancestors of the Polynesian Islanders of the Pacific are just two of many ancient cultures that depended heavily on celestial navigation. Their development of aquatic transport for travel, exploration, fishing and warfare relied on superb star-steering skills.
By 2,000 B.C., solar-lunar calendars were developed. In the millennia that followed, charts, compasses and navigational instruments were created for measuring the positions of vessels in relation to the stars and soon a new age of exploration was ushered in, culminating in the Vikings' “discovery” of North America around the 11th century A.D.
If you try tracing your ancestry on both sides of your family, it's highly likely that you'll find one ancestor or more who migrated from somewhere on a boat. What a very different place the world would be today if humans had never followed the stars in the first place.
Alfablue, April 2013