Chlorophyll isn't the reason they mature faster, their original native environment's light cycle and conditions change it's characteristics over time. Indica plants are typically found in areas with shorter growing seasons...either length of light or climate/temperature considerations. Sativas seem to thrive in hotter climates with longer seasons. As a general rule of thumb...the closer to the equator, the greater the chance the original plant was Sativa. Middle East mountains are home to more Indica, or hash plants because they mature faster.