[From many - one.]

Here, take a look:

Geoff's Photography - Scorpio, Mars and the Milky Way

http://home.iprimus.com.au/rsims/stars08.htm

Besides, the names and myths are also similar.

[TXnMA]

I do quite a bit of stargazing, and, fortunately, our place is situated well away from most light-polluting urban areas. On a really clear, dark night, few of the constellations are easy to discern -- because, (as in your time-exposed image) there are just too many stars visible. Under good (telescope) "seeing" conditions, it is even difficult for me to "pick out" Ursa Major or the "Big Dipper".

Actually, one of the best times to pick out constellations like Scorpio is when there is a full moon or a slightly hazy sky. (Or, in my case, when I have not yet switched off our mercury vapor security light.)

Although the Indians in the desert southwest didn't have time exposure cameras, they certainly had views of amazingly star-rich skies. OTOH, they had the same moon as we do -- and under those "light polluted" conditions, Scorpio does look very much like a scorpion...