I know that is not put on the blog and I have broken my good intention of the at least one post per week. You can scold him on. I could stand here and tell you how and the why of my absence (single quote, a great stay in Brussels), but it probably will not interest anybody.
But now, it's time to revive this blog, possibly to gain a greater frequency.
Today's theme, which is part of the basics of Paleostories (for the last time, I promise), concerns the extraordinary and rare biogeologist process that is called fossilization.
Generally, they are all considered fossil petrified remains of organisms that lived in the past (or rather, a period of time in the past that it can be quite dead, buried and fossilized) and possibly also any type of track which suggested their existence ( footprints, remains of excrements, traces of habitation, meal, eggs, deposits secretions, etc.).. A fossil therefore rapprendente something that was once alive (or connected to life) and, for reasons quite extraordinary, has been preserved in the form of rock.
For a living organism, becoming a fossil is by no means an easy task. This is because the inexorable fate of almost all (about 99.9%) of the organic matter in the world is to decompose and eventually disappear. On the death of an organism, cells and organic matter that makes up his body is used by other organisms (decomposers, predators) as a source of livelihood or taken from some other system. In nature, nothing lasts forever and everything is recycled. Can hurt, but it is.
also part of what you did qual'ora 0.01% escaped the action of the composition, your chances of fossilization would in any case very small.
reducing everything to the bone, you could say that fossilize requires very, very lucky: we must die in the right place (or be transported), be buried in time and in the right way, and, finally, be lucky enough to escape all destructive processes imposed on the rock strata of the earth, including one in which, fortunately before, you have found.
Only 15% of the rocks can preserve fossils. Igneous rocks of magmatic origin, obviously not conducive to the preservation any organic material, as well as those metamorphic (maybe even worse). To fossilize, it is necessary to happen in rock quite compact and safe to allow your remains to avoid the decomposition and transformation, through for example, chemical substitutions in mineral material in order to create a copy of the original Rocky.
Later, your loved ones sediments, guardians of what is left of you (already petrified), must bend, twist, press, without which you lose your shape and come broken, broken or crushed by the force of these processes.
And finally, if you want some 'of reputation (and do not have fossilized, say, human activities, "for nothing "), you should have the great fortune (perhaps even greater than all that had previously) to be recovered by any person and said the subject of scientific interest, because cestinaggio or indeterminate sleep in a drawer.
As you can see (and I've explained things very simply), fossilize is absolutely not a simple thing. A fossil, therefore, is something very rare. If in your life you will have the opportunity to pick up a fossil, regardless of their age, do you think are holding the remains of a creature that has had more luck than it would you if you win the lottery every year . Obviously, you have to multiply all for several million years.
For this, we know very little about the life of the past and its amazing forms. Almost all organisms lived on Earth up to now have left no trace of itself. And those who did, few have been discovered, thanks to the work (often poorly supported by the proper authorities to deal with large scale) of paleontologists.
It is believed that less than one case per 10,000 have left no fossil traces. The message is clear: what we have is just a taste of life developed on Earth. Moreover, often possess only a few remains of some animals (some fossil taxa, for example, are described on the basis of a few bones, or a few flakes, or indirect traces of activity). And, to make us even more evil, about 95% of more than 250,000 fossil species known so far belong to organisms that lived in the sea, so dangerously distort our picture of life on Earth.
In conclusion, we think for a moment this sentence: "quell'osso about 150 million years ago." Well, we are able to quantify 150 million years ago?
Someone like me, who does not remember what he ate for breakfast two days ago, is terribly far away that time.
Yet all the fossils in the world belong to a past much more remote than we can imagine. Much more than the life of our life. Sometimes the Romans seem far the Egyptians, the Sumerians. Yet, the ancient Egyptian hieroglyphs, dating to 5,000 years ago (more or less), are 30,000 times the most recent of our dear bone. The depth of time is the basis of paleontological research seriously, which implies the absence of reckless speculation on things that none of us will ever occur (such as a Tyrannosaurus eating as much meat per day, or how much distance travels in one year, a trilobite or whether it was the strongest guy or Dick, and other imaginative applications from TV).
True, many of the stories will later Paleo supposition of past events. A past in which no one can go back.
However, we give a little 'to honor those who have been lucky enough to fossilize, thanks to these we now know some (albeit poor) aspect of life in the past. And, in a rational, rigorous and conscientious attempt to analyze the aspects and groped to understand how things went.
Good.
Now we are ready to go.
PaleoStoria you at first.
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