Question

Pioneer species such as lichen and moss inhabit an area after a major disturbance such as a volcanic eruption. Over time, other species are found in the disturbed area and the number of pioneer species decreases. Why does the number of pioneer species decrease? The amount of available sunlight is reduced. The pioneer species can no longer thrive. ⊝ The area has more soil to support complex plants. The competition increases between organisms. ⊝ The area is more susceptible to the wind. Seeds are captured in the pioneer plants and germinate at a higher rate. ⊝ The temperature is not as extreme as it was following the disturbance. Fewer of the pioneer species reproduce. ⊝ CLEAR ALL ❮ PREVIOUS ... 3 4 5 6 7 8 9 10 11 12

Answer 1

The competition increases between organisms.

Step-by-step explanation:

Primary succession occurs after a disturbance or disaster that leaves open spaces with no living organisms. These new open areas are the case, for instance, of a bare rock exposed due to a retreating glacier, a volcanic activity, or an intense fire. No previous species inhabiting this area are left.

These scenarios allow new species to grow. With time, new species arrive and manage to establish again. The order of the establishment depends on the strategies of each of the species to survive.

First, pioneer species arrive. These are the first inhabitants, mostly lichens or plants with the capability of surviving in such an environment. Only a few pioneers can establish in the open space. Pioneers modify the habitat. They make it more suitable for the posterior establishment of later species, converting rock into fertile soil. As conditions get better, new species arrive like grasses. Grasses and pioneers keep modifying the ground and making it better with time. Competition becomes more frequent between species. The first species are eventually eliminated by competition, while new species keep appearing and competing for resources. Habitat modification keeps on going while new species establish. They produce shadows, alter the temperature, and humidity, fertilizing the soil, competing for resources. Competition becomes more frequent between species. This sequence continues until there is not more facilitation, and the commuting reaches a climax, becoming stable and lasting for hundreds of years until another disturbance occurs.