Originally Posted by watchdevil

I'll add my 2 cents. After 35 years of studying car design, the term "shouldered" or "shoulders" refers to how the bodysides steps out from the beltline at the bottom of the greenhouse. Most cars were shouldered up until the 1970's when cars most cars evolved into fuselage designs with no shoulders.

Some cars had what is called a "hop-up" in the shoulder behind the front doors. This is the proper description that designers used developing the original Mustang. This was a popular design element on numerous cars in the 1950's but the "hop-up" that most closely resembles the original Mustang is the 1956 Continental Mark II. The Mustang owes it's heritage and proportions to Continentals and Thunderbirds of that era.

Some late 1960's cars developed a Coke-bottle shape which resembles a "pinched waist" in the middle section of the car. Cars with a Coke-bottle shape follow human anatomy in this respect. You can say that some cars have "hips" because the quarter panels bulge outward from the center of the body.

The 1967-68 Mustang looked more like the 1965-66 started pumping up in the gym. From there it evolved into the 1969-70 Mustang wich had more of a "pinched waist" and "voluptuous hips". It still had a "hop-up" in the rear quarter panel but it was much softer and elliptical than before. This transformed the Mustang into looking more like an animal creature with haunches that was ready to attack it's prey.

The 1969-70 was less shouldered as the body began to evolve into a fuselage shape. The 1971 Mustang became a true fuselage shape when it came out with a more shallow shouldered beltline running from the front which disappeared as it wrapped under and up behind the rear quarter windows while the shape of the quarter windows suggested a hop-up on a relatively smooth and flat rear quater panel. The rear deck lines came forward and faded into the rear quarter panels.

The current generation Mustang is shouldered with no hop-up and no hips. The 2010 will be "shouldered" with a "hop-up" and evidence of hips as the quarter panels bulge outward away from the doors towards the wheel openings...

Originally Posted by watchdevil

If the rear quarter panels make the rear of the car wider than the doors then I consider that hips.

If the belt line raises up behind the doors under the rear quarter windows that is a hop-up and not hips.

Where the bodysides step out away from the greenhouse at the beltline that is shoulders.

1969-70 Mustangs have a combination of all of these elements.

Originally Posted by RCSignals

Yes some of these people posting are applying 'hips' to the wrong feature.

Originally Posted by watchdevil

Since the poll choice is between shoulders and hips, i'd have to go with hips. However they are formally described as hop-up by the original Mustang designers...

Quotes from Ford designers interviewed in the book Mustang! The Complete History Of America's Pioneer Ponycar by Gary L. Witzenburg...

Light Car Design Exceutive Don Kopka commenting on the 1967 project:

"In one of our early excercises we tried double hop-up fender forms. It was an interesting theme, but it seemed to chop up and destroy the classic Mustang proportions... We tried an extremely simple design with straight through lines. No hop-up, no bodyside sculpturing. Once we finished the model, it just didn't look like a Mustang. It was attractive enough but it looked more like a small sedan than a sports car."

"In our first crack at the 2+2 for 1967, we continued to persue the semi-fastback style of the 1965 fastback Mustang, but it was softer with more flowing forms... The most significant element of one model was a character line running the full length of the body. We discovered that it detracted from the strong feeling of the rear wheel opening by interfering with the hop-up configuration of the rear quarter panel."

Design Executive Gail Halderman commenting on the 1967 project:

"We took a number of cracks at it, but the way it turned out was to take the theme that had been established and make more of it. For '67 the theme revolved more around performance, so we made it stronger in appearance all over. That side scallop got deeper, for instance. and the grille and rear panel were enlarged. But we were very adamant about not changing the side fender/quarter panel profile... that rear hop-up look."

Originally Posted by watchdevil

If the belt line raises up behind the doors under the rear quarter windows that is a hop-up and not hips.

Where the bodysides step out away from the greenhouse at the beltline that is shoulders.

Originally Posted by RCSignals

You are to stuck on 'anatomy'. These are only terms used in design to describe features, and don't necessarily make sense if you are thinking about placement on a 'body' of a human or animal. Also, not all terms used are anatomical in reference.