What is missing from the ecosystem during primary succession

competition

Explanation:

After an ecosystem has been destroyed because of certain catastrophe and all of the space that it occupied is totally cleared and open for overtaking, the primary succession comes in action. When the primary succession occurs, there's no competition, as pretty much everything has been destroyed from the previously existing ecosystem. The pioneers of the primary succession are organisms that do not require a lot to prosper, such as the mosses and lichens. As they start to cover the barren land, little by little they manage to change the composition of the rocks, thus resulting in the formation of the first soils. As that happens, the secondary succession comes on the horizon as now it has conditions for it, so the species from it overtake and replace the species form the primary succession.

d concave shape of wave rock

explanation:

the concave shape of wave rock is a very good evidence that supports the evolution of earth due to chemical weathering. if we talk about structure of   wave rock, studies have estimated that it is around 2.7 billion years old. it also serves as the foundation of evidence that it was the place where australian continent began to form.

how the structure of wave rock was created?

studies suggest that structure of wave rock was created when the surrounded area was started to weather due to which deposition of material started on the part of land which now contains wave rock.

the structure of wave rock is considered to be one of the best-known landforms in australia. at the height of around 15 cm, there can be found flared slopes which formulate the margins of hyden rock. it is now assumed by geologists that wave rock was created by subsurface water-induced weathering and not by glaciers, waves or wind.

due to deposition of material over the period of long time, the wave rock became tougher and tougher due to weathering from surrounding terrain. this makes it a physical evidence that supports   the evolution of earth due to chemical weathering.

hope it !