水彩手绘生命之河生物迁徙插画素材

A wide scientific illustration showing the evolution of life as a clear linear progression along a winding path or river. The composition follows a guided timeline flow from left to right, like a “river of life”, where species evolve step by step along the path. Starting from primitive marine life in the ocean, then moving along the path to fish, amphibians, reptiles, dinosaurs, mammals, primates, and finally humans. The environment changes gradually along the path: ocean → shoreline → forest → land → modern environment. The path itself should visually guide the viewer through time, like a natural evolutionary journey. Not a random landscape, but a structured evolutionary pathway with clear direction. Style: clean, semi-realistic, slightly painterly, like a high-quality biology textbook illustration. No text, no labels, no infographic elements.