Have complex human-made things been designed?

I can only partially agree. It is true that humans do make incremental improvements to existing designs - and much software development is of this type - and this can give us some insights into how incremental design differs from de novo design.But that is as far as I can go.Consider the history of Windows:First there was MS-DOS which started life as "QDOS". QDOS was a cheap clone of an older program named CP/M, adapted to run on the new 16-bit 8086 processor. I can't see such a shift happening easily in biological evolution.MS-DOS was pretty limited at first, so it took code from another OS named Xenix, a Unix clone. While horizontal transmission of genetic material does happen in evolution, it is limited to genes. I think that the directory system would be a bit more than we would expect in biological evolution.MS-DOS was augmented by the original Windows. While this might be compared to symbiosis Windows was completely dependent on MS-DOS from the start - and remained so right up until the last of it's line WIndows ME. Again this is quite difficult in evolution.During this period a new operating system, Windows NT, was written that did not need DOS. While it took aspects from the older Windows (and doubtless it's authors experience writing for the unrelated operating system VMS helped) it was to a large extent a new creation. WIndows NT became WIndows 2000, then XP and now Vista.

There are two points I wish to raise:Firstly incremental changes still require design. Windows XP may be a smaller achievement than Windows NT, but the additions and changes made to it still required design. (I work at software development for a living, so I know that much !)Secondly, design does not directly produce objects at all. To claim that an F-16 is "not a product of design" because it was built in a factory is a category error. A design is all about what to build and how to build it - it is not the actual construction.(I would add that the distinction between design and manufacture is worth remembering in arguing with ID types. We often "recognise design" in human artifacts by seeing signs of human working - which is manufacture. Contrary to ID claims, design is usually inferred from that, not recognised directly)