Beak shape refers to the physical form and structure of a bird's beak, which can vary widely among species. Different shapes are adapted for specific feeding habits and environments. For example, hummingbirds have long, slender beaks for reaching nectar in flowers, while eagles possess strong, hooked beaks for tearing flesh. The diversity in beak shape is a result of evolutionary adaptations. Birds that feed on seeds, like finches, often have short, robust beaks to crack open hard shells. In contrast, waders like herons have long, pointed beaks for probing mud and catching fish.