Hummingbirds Speed Up Pineapple Plant Evolution

Hummingbirds have been identified as key drivers in the rapid diversification of bromeliads, the plant family encompassing pineapples. A recent study found that bromeliads pollinated by hummingbirds evolve into new species at nearly twice the rate compared to those reliant on bees, bats, or moths. This accelerated evolutionary process is attributed to hummingbirds' feeding habits in high-altitude, geographically divided areas.

Research compiling pollination data for 403 bromeliad types indicated that a substantial majority, three out of every four, are pollinated by hummingbirds. These plants speciate at a rate of 2.77 per million years, significantly higher than the 1.46 rate observed for plants with other pollinators. This highlights a dynamic evolutionary relationship, with pollinators having shifted over time.

This discovery is particularly noteworthy given the relatively young evolutionary age of both hummingbirds and bromeliads, with much of their diversity emerging within the last 20 million years. Bromeliads, known for their diverse forms including water-collecting tanks and air plants, share common ancestry with pineapples, distinguished by their fruit-bearing terrestrial growth.

However, this vital ecological partnership faces severe threats. Deforestation and climate change are endangering the mountain habitats of many bromeliads, placing 81% of these species at risk of extinction. Similarly, one in ten hummingbird species is at risk, and six in ten are experiencing population declines, underscoring the vulnerability of this unique evolutionary engine.