Flower pigments are changing as temperatures rise, ozone depletes

A new study in the journal Current Biology shows climate change is contributing to changes in flower pigmentation.

Clemson University researchers used flower pressings dating back to the 1940s to study how their ultraviolet pigmentation, which is invisible to the human eye but can be captured through UV photography, has changed over time. They found that higher temperatures and ozone depletion correlated with pigment increases and decreases, depending on the species.

A bit like putting on a white shirt instead of a black one on a hot day, flowers that protect their pollen with petals decreased their UV-absorbing pigment.

“That could be a thermoregulatory response to reduce the chances that they’re going to increase their temperature and bake their pollen,” said co-author Matthew Koski.

Conversely, flowers with exposed pollen increased their UV pigment.

Koski warned such changes could have consequences for the reproduction. He said UV pigment plays a role in attracting pollinators.

For more on his research, including which flowers and crops are still safe bets for attracting pollinators, click play on the audio player above.