Trees, Shrubs and Conifers: Curious branching pattern on our Gingko biloba, 1 by Decumbent

Decumbent wrote:
Please take a look at this pictures and tell me what you think would cause this "twinning" of the branch pattern. The main stem splits at chest heighth, and from that point on, each branch on one stem is almost always mirrored by a branch on the other stem. Notice the two additional splits, also, at the same heights. If you need more photos to better illustrate this strange pattern, I can get them

Scott