We know so far that Insects were roaming the new earth and were large in size due to plenty of oxygen. There is a possibility that Dinosaurs could of also been around the same time as the first Insects, as life on the planet would not of come to an abrupt end.
If the earth was going through climate change, there would have been a continuous life source from the beginning of time until today unless there is an interference from a solar system which produced a mixture of energy matter from exploding planets and stars, when combined together, this energy could have been distributed through the earth's atmosphere and produced a new biological species on earth.
As far back as we know, we have no written or any drawing report of any solar event producing a new species whilst man has been on planet earth, so let us now assume that during the beginning of life that all biological factors are now present on earth.