Which concept suggests that complexity in biological systems indicates design?

The concept suggesting that complexity in biological systems indicates design is known as specified complexity. This idea posits that when a system exhibits complex structures and functions that are also specified for a particular purpose, it implies an intelligent cause or designer behind that complexity. Specified complexity goes beyond mere randomness or natural processes to suggest that the arrangement and functionality of the components within a biological system are too intricate to have arisen solely through chance or naturalistic means.

In contrast, naturalism refers to the philosophical belief that everything arises from natural properties and causes, and supernatural or spiritual explanations are excluded. Species richness is a measure of the number of different species in a given area, and while it reflects biodiversity, it does not inherently imply complexity related to design. Biological evolution explains the diversity of life through processes such as natural selection and genetic drift over time, focusing on gradual changes rather than the implications of design in complex systems. Therefore, specified complexity specifically addresses the relationship between biological intricacy and the inference of purposeful design.