Question

krakatoa was an indonesian island that was completely obliterated in 1886, when a massive volcano exploded on the island. underwater lava flows slowly rebuilt a new island, called anak krakatau, by 1927. on anak krakatau, the first organisms to arrive were small weeds. the weeds then gave way to coconut trees. land crabs, seagulls, and rats began to colonize the island. by the 1980s, coconut trees gave way to tropical eucalyptus trees inland. wild pigs and large lizards colonized the island. in the future, a mature rainforest will re - grow. what process occurred on this island? a speciation b niche formation c primary productivity d ecological succession

Explanation:

The problem describes the process of an ecosystem recovering and changing over time after a volcanic eruption, with different species colonizing and the vegetation changing (weeds → coconut trees → Eucalyptus trees, and animal colonization too). Ecological succession is the process of change in the species structure of an ecological community over time, which matches this scenario. Speciation is the formation of new species, niche formation is about organisms' roles, and primary productivity is about energy capture by producers—none fit as well as ecological succession.

Answer:

D. ecological succession