Foxgloves evolving for pollination by hummingbirds in the Americas

They adapted so Hummingbirds can pollinate then, fascinating .

Not quite. That implies forward planning etc. Hummingbirds could always pollinate these flowers.

More like: Hummingbird pollination compared to bee pollination may incur a selective advantage to those foxgloves with longer pollen tubes over those with shorter pollen tubes. Consequently, longer-tubed foxgloves have become more frequent in South America, possibly because hummingbirds account for a significant proportion of pollination, when compared to ancestral foxglove populations in Europe, where there is no hummingbird pollination.

The original paper is here.

Apologies. Pedantic biologist here.