SQL Server Replication Stored Procedures sp_MSdel_db, sp_MSupd_db, sp_MSins_db
Jeff - Have a look at the parameters for sp_addarticle.  Notice the parameters @ins_cmd, @upd_cmd, and @del_cmd can be configured to replicate inserts, updates, and deletes as either stored procedure calls or straight SQL.

DBA number 1 likely setup the production publication to replicate inserts, updates, and deletes as SQL.  DBA number 2 likely setup the development publication to replicate inserts, updates, and deletes through called stored procs.