Plankons, fungi, bacteria, lichens etc. are the pioneer species of ecological succession. Pioneer species are hardy species which are the first to colonize previously biodiverse steady-state ecosystems. Some lichens grow on rocks without soil, so may be among the first form of life the example includes bacteria, fungi, and lichens.
1) Are they reliable? 2) Are they relevant? 3) Are they recent? 4) Are they sound resources? 5) Are they a primary source? 6) Are they a secondary source?
