Some of the classic examples of evolution given in biology textbooks involve loss of structures.
One of the examples was of the evolution of the horse, often cited as a classic example of evolution by evolutionists. The horse started off as a small creature in the Eocene eating leaves in forests and walking on three toes on the back legs and four on the front legs. Later with the spread of grasslands, the horse grew larger so it could run faster; it developed teeth that could cope with tough grasses instead of soft leaves as its diet; and it lost toes. The horse now runs swiftly on hooves that represent a single toe for each leg. The horse’s evolution involved loss of digits. Vestigial digits are still found part way up its leg.
You could say that the horse has ‘devolved’ – but devolution is a separate subject – what I mean is de-evolved.
You’ll notice that the yellow Alstrumeria in the photo has lost most of its stalk and leaves as it is adapted to desert conditions. This is a similar example of evolution in the plant world.