In a message dated 98-08-09 00:17:07 EDT, sarima@ix.netcom.com writes: << In the case of hominids, it was due to the overly long arms, derived from their unusual use in locomotion. >> Perhaps some day we'll find the remains of a brachiating small theropod. That'll be most interesting for BCF--long arms are one big step closer to wings than short arms.