Read the passage below:
While classical ecological models assumed that island ecosystems reach an equilibrium state primarily governed by a balance between immigration and extinction rates, recent studies of subterranean lava tube fauna present a compelling challenge to this paradigm. Proponents of the classical model argued that species richness on isolated landmasses remains relatively static over evolutionary timescales once carrying capacity is attained. However, subterranean habitats often display continuous, non-equilibrium lineage diversification driven by micro-refugia within volcanic strata. By examining adaptive radiation in these underground networks, subterranean biologists have demonstrated that internal micro-environmental heterogeneity can sustain speciation independent of ongoing surface immigration. Consequently, rather than viewing these subterranean communities merely as passive sinks for surface waifs, contemporary researchers increasingly regard them as dynamic evolutionary nurseries that generate novel biodiversity.
Which of the following statements correctly describe the rhetorical functions of specific elements within the passage? Select all that apply.
- The reference to the classical ecological model serves to establish a baseline theoretical perspective that the author subsequently qualifies.Answer
- BThe sentence describing proponents of the classical model provides empirical evidence intended to undermine traditional equilibrium theory.
- The clause introduced by 'However' functions as a structural pivot that shifts the passage from explaining a traditional assumption to introducing counterevidence.Answer
- DThe final sentence functions primarily to disprove all existing research regarding surface immigration on oceanic islands.
- EThe mention of 'micro-refugia' serves to demonstrate that subterranean ecosystems are entirely hostile to surface-dwelling organisms.