Temp tablespace being recreated on startup ?

I am testing some recovery scenarios and noticed something. If I remove the temporary tablespace file from the operating system and shutdown and startup the database, the database software recreates the temp tablespace file. When did this functionality start occurring? Is there any documentation on the functionality?Thanks.

(ie) An example in 11.2.0.2.0

SQL> startup;
ORACLE instance started.

Total System Global Area 1570009088 bytes
Fixed Size                  2226832 bytes
Variable Size            1090520432 bytes
Database Buffers          469762048 bytes
Redo Buffers                7499776 bytes
Database mounted.
Database opened.
SQL> !ls -l /u01/oradata/C001/*
-rw-r----- 1 oracle oinstall  10338304 Jan 23 15:28 /u01/oradata/C001/control01.ctl
-rw-r----- 1 oracle oinstall  10338304 Jan 23 15:28 /u01/oradata/C001/control02.ctl