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Introduction :
A fossil is a trace left by a living being, the fossils are very important because they tell us about the species that have ever lived at that time but also on conditions during it. Finally it is also possible to use compared fossils of a rock to date or determine the conditions of its formation.
The lesson to learn from fossils :
The fossils of the first multicellular animals, of a very simple organization, were found in Ediacaran in Australia, they are jellyfish floating in the water, marine worms inhabiting the seabed and plumed shaped corals. These are the first traces of the living environment of which we have accurate knowledge.
But it is actually at the beginning of the primary era during the Cambrian when life explodes. Thus, we find many fossils of living beings equipped with external limestones and fossils of the most numerous organisms have a shell like current crustaceans.
The fossils found today and dated from this period are the traces of a sudden and large diversity of groups whose cause is still unexplained.
Among the many fossils found by man, some are of intermediate forms, ie the key stages of evolution, the most famous is the Archaeopteryx dated from 140 million years ago; it has both bird (feathers) and reptiles (teeth) features.
Reminder on "Earthcaches": There is no container or logbook on the given coordinates. Just visit the site and answer the questions by e-mail.There is no need to wait for my reply, feel free to log immediately after. If the answers are incorrect, I will let you know. Happy caching!
To validate your visit:
1-. What do we find as fossil in the stage after the appearance of microorganisms?
2-. How old is the first environment of life of which we have an accurated knowledge?
3-. The first vertebrate fossils were found in rocks of about 500 million years old, but what were these vertebrates?
4-. Name other fossils which show the juxtaposition of features of the two different groups.
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