[Thankfully, it takes a lot more to surprise him. In fact, he's so fascinated with the egg that he doesn't process that someone's even spoken to him until a good thirty seconds after.]

Hmm? Oh, hullo! [He throws her a smile and turns immediately back to the egg.] And yes, well, obviously. [Carefully, he tucks the sonic screwdriver back into his inside jacket pocket.] It's an egg, one of many. And there are definite life-signs coming from within, but nothing that indicates what it is, or if it's ready to come out. Never seen anything like it before. Eggs usually aren't this beautiful. No reason for them to be, you know? Well, unless they're Easter eggs or ones that people have hollowed out and carved gorgeous designs on, that is. But naturally? Nothing like it.

[He reaches out a hand just then to touch the top of the egg.] It's warm. [And then there's a sudden sound, like a crack. His eyes widen.]