"Melinda, look over there." Sarah pointed to a large bone situated in the walkway so visitors could touch it.
Her daughter hurried over and stroked it as if it were a pet kitten. Sarah noted how Melinda's tiny hand was dwarfed by the bone and moved to place her own slightly larger hand on top of her daughter's.
"Wow." The word came out in a breath of air. "Mommy, do you think ... Is this a T-rex bone?"
"Actually," a man spoke from behind them, his Scottish burr musical, "it's the right humerus from a brachiosaurus altithorax."
Sarah jolted in surprise at the sound of his voice, loud and unexpected in the quiet of the aisle.
Melinda turned her gaze to the speaker, a tall, black-haired man in a tailored gray suit.
"That's a veggie-saur," Melinda commented.
"That's right, he was an herbivore. You're very smart."
Sarah looked on as the man squatted down on eye level with her daughter and tapped her tiny button nose with his index finger.
"The brachiosaurus was enormous. If you were inside the fifth story of a building, brachiosaurus could peek in through the window so you could pat him on the head and feed him lettuce."
Melinda giggled at the idea. Sarah kept a cautious eye on the pair, suspicious of any stranger who would butt into their conversation.
As if he'd sensed both her gaze and her apprehension, he turned to face her. He smiled before standing and extending a hand. The corners of his cobalt eyes crinkled at the sides and, when Sarah tipped her head back to look up at him, she noticed several permanent lines there--as if smiling was a habit of long standing.
"I'm Doctor Duncan MacPherson. I'm a guest speaker here this week."