What is one main characteristic that distinguishes ecofacts from artifacts?

Ecofacts are defined as naturally occurring items found at archaeological sites that provide information about the environment, diet, and the ecological conditions in which human activities occurred. The key characteristic that distinguishes ecofacts from artifacts is that ecofacts have not been altered or modified by human activity; they remain in their natural state.

This characteristic is crucial in archaeology because it allows researchers to analyze how humans interacted with their environment without the influences of human craftsmanship or modification seen in artifacts—objects created or altered by humans, such as tools or pottery.

The other options present inaccurate information regarding ecofacts, such as them only being found in specific environments or being inherently larger or made from certain materials, which do not define what ecofacts are at their core.