Acasta rock, dated from 4,05 billion years founded in Canada.

Our little blue planet we usually call “earth” has about 4,5 billion years. It is a scientific question based in measurement, so, I don´t have words to say for people who follow misticism and false ideias. I only can say, if someone believe God created our Universe, it´s very simple to see He did all things in strong basis we call “scientific laws” which we are always trying to understand and be guided by as a “light” against fear and ignorance.

Another comment : The fact of some religion have ancient writings stating the world has about 6.000 years can not minimize his importance and magnitude, since your leaders can teach people how to understand and contextualize his beliefs getting the best interpretation in order to never hide the “flame of the truth”. As a good example, the medieval catholic church was against Galileo Galilei discoveries but in recent years claimed excuses for it. Convivence between Religion and Science is always possible. This will be the subject of a future post.

Rocks are formed by minerals and each one has a “chronometer” of geologic time inside. When one mineral is formed (which happened when earth was formed), in this exact moment starts a nuclear decay transforming progressively this element in another. For example, the uranium (isotope 235) takes 4,5 billion years to transform a half of itself in lead. This decay is called a “half life” of the element. Through measurements of the proportion of new elements and original ones inside samples from rocks and outer space meteorites, the earth´s age has been estimated.

Imagine a time line, an straight axis from zero to 3,000 divided in equal parts and then take the last one. It represents roughly the amount of time the human specie is living on earth (1.5 million years) as the exact time we start to be “human” we don´t know exactly. It is a controvercial subject but do not change our analysis.
Put in this time line some species no more lives between us. Pré-historic invertebrates and vertebrates animals as reptiles including more than 1,000 species of dinosaurs knowed (a formidable Tyrannosaurus for example) and others categories of reptiles like plesiosaurs, pterosaurs, mosasaurs, ichthyosaurs and crurotarsans. Inumerous species of fishes, birds, amphibians, mammals (as saber-toothed and mammute species like mastodons, for example), pelycosaurs and many other totally extincted.

Divide the last part in 1,000 parts and take again the last one. It represents the modern species are being extinted by climate changes and another factors. You can put there birds for instance. Since year 1,500, 190 species of birds become extinct as the Dodo bird. There are today about 10,000 species with roughly 1,200 are considered to be under threat of extinction.

The pollution is not responsible for all, human behavior ad society way of life determines how agressive humans are against the nature. Romans hunted thousands of animals for spectacles in Colosseum and they were responsibles for regional extintion of many species as elephants and lions in North Africa, syrian elephant, atlas bear and hippopotamus in the Nile. They drained lakes and diverted rivers causing deep ecologic damages and creating in our colective inconscience a false paradigm that men could dominate and change the environment as they want.

Looking this time line for some minutes you will certainly formulate one question : in the next point we will stay here ?
The answers to this question will be analised in the nexts posts. Think about for a while the actions you can do to increase our chances to remain in the time line and, if you have a belief, pray sometime for our continuity on earth.

See: First post of the series