Biology STAAR Practice Test 2026 - Free State of Texas Assessments of Academic Readiness Practice Questions and Study Guide

The environment plays a critical role in influencing evolution through the concept of natural selection, which occurs when certain traits become more or less common in a population based on their advantages or disadvantages in a specific environment. Selective pressures, such as changes in climate, availability of resources, predation, and disease, can favor individuals with traits that enhance their survival and reproduction. These advantageous traits are then more likely to be passed on to subsequent generations, leading to evolutionary changes over time.

For example, in a habitat where food is scarce, individuals in a population that can efficiently find or utilize resources may have a better chance of surviving and reproducing compared to those that struggle. Over time, this can lead to increased prevalence of traits that confer this advantage, demonstrating how the environment directly impacts the direction and pace of evolutionary change.