The Epoch of Humans

The Earth is 4.6 billion years old; we, humans, are 200 thousand years old – which means that if the planet would be summed up in one day we would appear only in the last second. That did not stop us from building cities, destroying forests, excavating soils, polluting oceans and the air or taking other species to extinction while growing in more than 7 billion people. In view of changes in climate, atmosphere, rivers and biodiversity scientists point out that the planet is no longer the same our ancestors found or that of the geological epoch in which we have lived the last 12 thousand years, the Holocene, where the earth climate was propitious to our development. Now they are researching in which moment of our history we entered in this new era deeply marked by us, the Anthropocene.

Agriculture brought forth the possibility of storing food. Thus, certain peoples quit the simple structure of hunting and collecting that would lead us to incessantly wandering to another structure of cultivation which was the based for the first villages. Origins of cities these sites started being built 4 thousand years ago on the margins of the great rivers such as Nile, Tigre and Euphrates in Mesopotamia, Huang Ho in China, and Ganges and Indo in India, Eurotas in Greece, Po in Italy and the Rio Grande de Santiago and Balsas in Mexico. Like hieroglyphs and old monuments these were the first prints we left in the planet; the agricultural potential would further increase with irrigation channels, ploughs and rotation of soil, but the very cycle of nature would assure the regeneration of what was extracted by these peoples.

Spread out through the planet some peoples became great empires others remained isolated. Europeans, Africans and Asians had known each other way back but for centuries they had no contact with the lands they would later call America and Oceania. The planet cartography remained unfinished until the great navigations from the 16 th to the 18 th century when Europeans learned about the territories and peoples of the New World. These expeditions enabled the “discovery of the planet” as we know it today: six continents, five oceans, hundreds of archipelagos and thousands of species. But this was period marked both by the fascination of discoveries and by enslavement and decimation of entire populations; this was also the moment in which a network of commercial routes crossed continents and oceans involving the entire planet.

As of the 19th century, mankind fingerprints on the planet were larger and more evident, starting with population and the big cities. In England, the cradle of the Industrial Revolution, London reached 1 million people in 1800 being the first modern city having this number of dwellers. In 1900 there were already 12 cities with this population, and 15% of the world population which was around 1.65 billion lived in urban areas. These numbers continued increasing: in 1927 we were 2 billion people in the planet; in 1950 more than 2.5 billion and in 1960 3 billion. On the turn of the century, the world population already approached 6 billion and almost half of it lived in cities. More than 400 cities had more than 1 million inhabitants and 19 had more than 10 million. Today we are more than 7 billion people, more than half lives in cities. Forty-four cities have between 5 and 10 million residents, 29 have more than 10 million. All this growth in one century only becomes still bigger if we consider that mankind took longer, from its origin, 200 thousand years ago, to reach one billion.

The fast growth of the world population in the 20 th century was accompanied by an increase of consumption of fossil fuels, foodstuffs, water, products and ore. If the nature before was capable to restore what we extracted that no longer occurred in the seventies when the quantity of natural resources explored in one year became higher than the capacity nature has to replace them in the same period. In 1971, we exceeded this limit in December; in 1981 in November and currently the “planet overload” happens in August. The pressure over the planet is so high that it would be necessary one and half year for the nature to replace what we consume in one year. But that does not mean that there is an equalitarian distribution of its resources: inequality is one of the marks of the globalized capitalist world: an American consumes 11 times more than one African or South-Asian and has a carbon footprint 250 times greater than an Ethiopian.

The crossing of long distances was made easy by invention of ships, trains, automobiles and airplanes. The speed of information also increased, after press, with telegraph, telephone, radio, TV; to make that possible the cities required the construction of systems with thousands of wires, cables and lead pipes crossing underground – subsequently replaced by copper cables and then fiber optics. Today a global conversation happens in real time by cell phones, Internet and new information and communication technologies: it crosses the planets by SMS, tweets, hash tags, etc. The power to communicate is literally in our hands and the world seems increasingly smaller and increasingly more connected.