Why are most S-Expression languages dynamically typed?

Question

How come most Lisps and Schemes are dynamically typed? Does static typing not mix with some of their common features?

Answer 1

Typing and s-expressions can be made to work together, see typed scheme.

Partly it is a historical coincidence that s-expression languages are dynamically typed. These languages tend to rely more heavily on macros, and the ease of parsing and pattern-matching on s-expressions makes macro processing much easier. Most research on sophisticated macros happens in s-expression languages.

Typed Hygienic Macros are hard.