Nope, do not believe so. The short tail with a vertical back is called the Kamm effect. It's a mix between having a practical design and minimizing drag. The numbers do not lie; there is a reason the Prius has an extremely low drag coefficient.

Just think this through on a systems level. Obviously Toyota's engineers are not idiots and would use whatever aerodynamic effects they would since the entire point of the car is maximizing efficiency. If it was more efficient to have a different shape while still remaining a practical automobiu, it would. The entire design of the Prius revolves around this.