Analysis of information sources in references of the Wikipedia article "Kambriske Eksplosion" in Danish language version.
The Cambrian Explosion (570 to 530 million years ago)
It's important to remember that what we call "the fossil record" is only the available fossil record. In order to be available to us, the remains of ancient plants and animals have to be preserved first, and this means that they need to have fossilizable parts and to be buried in an environment that will not destroy them.
But it was not as rapid as an explosion: the changes seems to have happened in a range of about 30 million years, and some stages took 5 to 10 million years.
The Cambrian Explosion (570 to 530 million years ago)
