F1 photographer Darren Heath nails it:

“The slate-wiping revolution that’s swept through F1 has reminded everyone of just why our sport is so special. Just think of what the teams have achieved in such an incredibly short time. Brazil 2013 marked the end of a prehistoric age for the sport, the ancient ‘technology’ employed to propel the cars finally being consigned to the trash. Five short months later completely new engines, ERS, electrics, turbos, braking, aero et al practiced, qualified and raced hard around Melbourne’s Albert Park circuit.”