Nautilus Shell
The chambered nautilus grows its shell in a logarithmic spiral closely approximating the golden spiral. Each chamber is roughly 1.618x the size of the previous.
Sunflower Seeds
Sunflower heads arrange seeds in intersecting spirals -- typically 34 and 55 (consecutive Fibonacci numbers), maximizing packing efficiency.
Galaxy Arms
Many spiral galaxies, including the Milky Way, display logarithmic spiral arms that approximate the golden spiral at cosmic scales.
Pine Cones
Pine cone bracts spiral in two directions with counts that are consecutive Fibonacci numbers (8 and 13, or 5 and 8).
Human Body
The ratio of forearm to hand, navel to floor vs. total height, and DNA double helix dimensions all approximate phi (1.618).
Flower Petals
Lilies have 3 petals, buttercups 5, delphiniums 8, marigolds 13, daisies 21 or 34 -- all Fibonacci numbers.