Day 160 of Wonder

It's the season for flowers and so it is almost impossible for me to walk outside without being inundated with multiple choices of those that awe me. These yellow roses were just asking for me to stop and admire them. In this gorgeous ensemble I found the oldest, the older and the newest roses alongside various buds. The colour, texture and depth and complexity of petal work is sublime. Does anyone know why the bud shows pink when the rose is so clearly yellow?