Why capital D/G but lower case d/g?

[Phanerothyme]

It all pretty much stems from the birth of movable type I would have thought - many of our spelling conventions and letter formations do.

[LordChaverly]

The answer is quite simple, if you approach the question in the right way.

 

Implicitly or explicitly, the contributions so far appear to assume that the development of the lower case letters preceded those of the upper case letters, whereas the opposite appears to be true. In other words. 'D' and 'B' preceded the formation of 'd' and 'b', not the other way round. Had the early calligraphers not found an alternative, a lower case 'D' might look like a lower case 'O' or a lower case 'B' (i.e. an 'o' or a 'b'). Similarly, a lower case 'G' might look like a 'c', or even a 'p'.

[euclid]

This must be a typist's/secretary's post........i'm off..