Convergent evolution—the repeated evolution of similar traits in multiple lineages which all ancestrally lack the trait—is rife in nature, as illustrated by the examples below.
Distantly related organisms often develop analogous structures by adapting to similar environments.
Here is a list of examples in which unrelated proteins have similar functions with different structure.
Here is a list of examples in which unrelated proteins have similar tertiary structures but different functions.
The most well-studied example is the Spike protein of SARS-CoV-2, which independently evolved at the same positions regardless of the underlying sublineage.