Astronomers and astronauts are engrossed in the possibility of traveling to new worlds. The exploration of the heavens led to the first people to leave the Earth and circle in orbit which in turn led to the first moon walk and now have turned our attention to Mars. Astronomers discuss the possibility of colonization as we search for life on other worlds. We continue to push the limits of our lives and to find new ways to take a step further. Humanity needs people who will smash through glass ceilings and take our species to the next level. This is progress. The desire for exploration not only defines our current political systems from exploration and exploitation, but also marks the requirement for evolution of our cultures and our species.
Exploration Age
In the 1400’s, Europeans caught the exploration bug. Beginning with the adventures of Marco Polo, who did more than create an annoying game, Europeans searched for newer and faster paths to reach the orient. This led to the discovery of new parts of Africa as they round the Cape of Good Hope and eventually to the exploitation of African resources. But the explorers found a way to the Orient. Soon, Cristobal Colon convinced the Spanish Crown that he could reach the Orient by sailing West over the horizon. Colon’s famous three ships never made it to China or India, but found a new world full of exploration, colonization, and exploitation. Europeans began migrating to the New World through the door opened by the exploration age. This marks the beginning of the globalization which we find ourselves in now. Had the famous explorers stayed upon their native shores, my ancestors would have remained in Europe. The populations of humanity would have remained separate through limited contact with other ethnicities. The Exploration Age was an important step in our history as a species. As school children memorize the impact of our heroes, we should recognize that this is not the first time that our ancestors explored new lands and expanded the limits of our knowledge.
The Journey of Man
Before 80,000 years ago, the only humans lived in Africa. Ethiopia is rich in human fossils helping modern anthropologists decipher our humble beginnings as a species. Our human ancestors were smarter than their rivals with the ability to produce better tools and greater thinking abilities. But they also had the urge to explore. About 100,000 years ago, anatomically modern humans (AMH) fossils were found in the Middle East, but for whatever reason this exploration failed to gain any ground. They may have been forced to stop because of starvation, infection, or conflict with the Neandertals who took over the area after them. So our ancestors we stuck in Africa for another 20,000 years. During that time, our species evolved the many characteristics we consider to classify our humanity. The eagerness of exploration must have surged like a river running up against a dam and 80,000 years ago the dam broke. Humans began to leave Africa by reaching the southern part of the Arabian Peninsula, which was probably exposed by lower sea levels. From there, our human ancestors migrated along the coast of Asia keeping to the shore as a source of food. Many fossils and relics from this migration are probably under the rising sea levels at the coast of Asia. From this migration, humans began to colonize the Middle East, Polynesia and Australia. This surge of exploration was halted for sometime. An Ice Age and Neandertal competitors blocked the access to Europe until about 50,000 years ago. At that point, humans migrated with the retreating glaciers and probably led to the extinction of our close cousins. Humans also migrated across from Russia to Alaska to colonize the “New World” about 15,000 years ago.
The Human Migration out of Africa has been important in the study of Anthropology. The World Genographic Project is seeking DNA samples from indigenous peoples to help us trace our long forgot explorers. Without this migration, humanity would have remained in Africa and our current lives would be drastically different. Our population would not busting at the seams of 7 billion people, and Africa would be considered the center of the world. Without the desire to explore, we may not have the culture that we have today. Science would not have developed which requires the urge to explore your surroundings. So our exploration is deeply engrained in our genes. Deep within our chromosomes and our culture the horizon is calling for the exploration of our ancestors. But the desire to explore can be found even deeper within our ancestry before we left Africa, before we were even human.
Walking Tall
Lucy was curious. Her family group had settled in this area long ago, but she wanted to know what was in her surroundings. A drought and changing climate had made food scarce and her family needed to know where to look for food. So Lucy did something that no group of ancestors had done before. She stood up and walked.
The discovery of Lucy has been celebrated as one of the greatest achievements in anthropology and the understanding of our human origins. Lucy is not a human being, but a member of a species that helped to establish bipedality as a hallmark of our ancestors and changed the way we think about human evolution. The Australopithecines were the first apes to be discovered that were bipedal and served as a nail to link humanity to the other Great Apes. The story of Lucy and her kind is another story of exploration. At the time australopithecines are evolving in Africa, the lush forests that were home to the great apes were giving way to the Savannah. Lucy’s species required trees and retained many characteristics which places her in the trees for much of her life. As the Savannah came in, patches of trees became further apart from each other. Once her family had exploited all the resources of one tree they would have to move on to another patch. Crossing the Savannah is a dangerous process, but Lucy had a trick up her sleeve. Because Australopithecines are bipedal, they can stand up over the tall grasses to see any potential dangers. Their ability to walk left their arms open to help carry food while keeping an eye out for any enemies. As our ancestors become more adept and adapted to walking, the arms remained free for other purposes. Exploration from walking probably gave the nudge to the evolution of tool making and the dramatic increases in brain size that soon followed Lucy’s kind. Talk about one small step for Lucy, one giant leap for mankind!
Into the Trees
Imagine the world 65 million years. Not that long ago, Dinosaurs ruled the world. Whether an asteroid corresponded with or caused a series of massive volcanic eruptions, all non-avian dinosaurs are extinct. Somehow, mammals and other animals are able to survive. In this emptied world, a variety of habitats and niches are now open to exploration and exploitation. Eventually, a group of small mammals scurry up into the trees and over millions of years their adaptations would be used in the classification of primates. Many of the anatomical traits that we take advantage of can be traced back to the exploration of the trees by our earliest primate ancestors. Long arms with grasping hands and feet enable these explorers to swing through the canopy like a trapeze. Primates soon specialize our binocular vision which provides the depth perception required when jumping from branch to branch. At this same time, flowering plants and fruit bearers co-evolve with our primate ancestors who develop tri-color vision which helps them pick out the best fruits in the trees. The proliferation of mammals after the extinction of the dinosaurs provides a stunning example of the adaptive radiation from colonization. If those early mammals and primates had not explored those newly opened habitats or exploited those freshly available niches, many of the traits that we take pride in may have never been seen.
Out of the Water
Before 380 million years ago, vertebrate animals could only be found in the oceans. There was a wide diversity of fish species all specialized to life in the oceans. Some fish were getting bigger, some were getting faster, some were getting defensive, but some were getting out of the water all together. The exploration of the land requires many changes from the fish body plan to achieve the tetrapod lifestyle. An amazing fact of tetrapod evolution is the variation upon the theme of limbs. All vertebrates that live on land have found new and interesting ways to exploit their niche through variations of their four limbs. But the important step was the first “step” out of the water. A small group of ancient fish had some interesting adaptations. First of all, the lung fish was found to possess lungs and a single arm bone attached to a shoulder. This is the beginning of tetrapod limbs. Generations of species later found fish that had a humerus, radius and ulna. The recent discovery of Tiktaalik shows that these fish that contained lungs, also had a wrist. Animals like Tiktaalik needed to get out of the oceans either for protection or to find food. Points of muscle attachment show powerful muscles were attached to the limbs of these fish with wrists which allowed Tiktaalik to do push ups like seals do to scan the environment for dangers. The exploration of land by full tetrapods was not much longer and the diversity of tetrapods can be seen on a daily basis.
The Thrill of Discovery
There is nothing like discovery. To see something that no other person has seen can be thrilling and humbling. While we take our dream of exploration to new worlds, we should take a moment and salute the explorers that came before us. Our greatest discoveries are definitely achieved by standing on the shoulders of giants: Men, women, primates, and fish.
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