Answers

2014-08-20T17:07:31+05:30
Yes, there is a scientific reason. The black is carbon powder added to the rubber. Basically, carbon improves the puncture strength and tread wear resistance to rubber.

They were not always black. At one time, most of the pneumatic tires were white, as depicted in the following photo:
3 4 3
yeah you're right they were called white walled tyres and wouldn't blend with the road.
NICE ANSWER!
NICE ANSWER!