Pollination patterns reveal the climate behind plant evolution

A plant’s pollination method can indicate whether its species evolved during one of Earth’s hottest or coldest climate periods, according to a new study reported by ERR.

Researchers from the Estonian University of Life Sciences, the Czech Republic and France compiled the family tree of 1,178 native flowering plants in the Netherlands, representing the country’s entire flora, and compared the plants’ evolutionary ages with ancient temperatures.

The analysis showed that unusually many plant lineages emerged during the planet’s warmest or coldest periods. Far fewer surviving plants originated in eras with moderate temperatures.

The contrast became sharper when researchers examined pollination methods. Wind-pollinated plants mostly originated during the coldest geological periods. Among insect-pollinated plants, butterflies were associated with species from periods of extreme temperatures, while plants favoured by bumblebees and wasps were linked mainly to eras with intermediate temperatures. Plants pollinated by flies and beetles again showed a stronger connection with cooler periods.

The researchers said the pattern is linked to survival. During cold periods, when insect activity fell significantly, plants were more likely to rely on wind or on cold-tolerant flies and beetles to carry their pollen. Butterflies need considerable warmth and sunlight to fly and search for food, so plants associated with them gained an advantage during warmer periods.

The ancient legacy can also be seen in plants’ present-day seasonal rhythms, the researchers said. Species that emerged during hot periods tend to bloom in the warmest months of summer, while plants with a cooler evolutionary past are more likely to open their flowers during the cooler part of summer.

The findings were published in the journal Ecology and Evolution.