They differ from the other swifts in that they have crests , long forked tails and softer plumage .
The treeswifts , or crested swifts , are closely related to the true swifts .
swifts differ from the other swifts in that they have crests , long forked tails and softer plumage .
The treeswifts , or crested swifts , are closely related to the true swifts .