The entire sentences you give are both complete sentences, not fragments.
However, there is no finite verb in either of the clauses which you boldface, only a present participle; consequently these are not, by themselves, full clauses but (as traditional grammar calls them) 'fragments'. They are subordinate clauses which cannot stand on their own. Consequently no conjunction is required here, and there is no comma splice.
Formally they are absolute clauses: because they have no finite verb they are taken to be subordinate to their head clauses, but because they have their own subjects (this development and this) they cannot be taken to modify a specific constituent of their head clauses; consequently they are taken to be 'supplements' providing additional information.
Incidentally, we do not say wonder on, only wonder about.