Practice question

“Temperate grassland” for what biome has cold winters, hot summers, and fertile soil. This relationship follows from the ecological mechanism represented by the terms in the item, not merely from an association between their names. Plant growth form integrates water balance, fire, frost, nutrient availability, and growing-season length. Animals respond to the same filters through migration, dormancy, thermoregulation, and dietary specialization. The remaining alternatives—“Savanna”, “Tundra”, “Temperate deciduous forest”—refer to different states, processes, or scales and therefore do not express the same causal relationship. A biome label describes a broad climatic and structural pattern rather than a single taxonomic assemblage. Similar climates can produce convergent vegetation on different continents even when the species themselves are unrelated. Field observations could test this account by measuring the proposed driver and the demographic or ecosystem response while controlling plausible confounding factors. This distinction matters because similar surface patterns can arise through different mechanisms, whereas ecological prediction depends on identifying the mechanism that actually changes rates.