Shake what your mama gave you - increased native hybridization with climate change
Summary
In addition to outcompeting native species and altering habitats, invasive species pose a threat to native species by hybridizing with them. Invasive hybrids can have traits that allow them to outcompete both parent species while diluting the gene pool of native species. But it is unclear whether climate change will affect the likelihood of hybridization. Gallego-Tévar et al. examine this process in the context of hybrid crossing between two species of cordgrasses in Spain: native Spartina maritima and invasive Spartina densiflora. They found that both hybrids of these species (S. maritima x densiflora and S. densiflora x maritima) are more likely to form with climate change when warmer springs increase the likelihood that flowering times will overlap and reduce pollen counts in the native S. maritima. Additionally, both hybrids have competitive advantages over their parent species, increasing risk to the rare native S. maritima.
Take home points
Hybridization between native and invasive plants could increase under climate change as warmer temperatures extend flowering times and allow for greater cross-pollination.
Hybridization between the same two species can result in different traits depending on whether a given species acts as the pollen source or the seed source.
Management implications
Spartina hybrids in Spain have a competitive advantage compared to both parent species and may be more likely to establish and spread with increased disturbances in coastal wetlands.
Native and introduced species of the same genus could be more likely to hybridize with climate change if flowering times become longer and begin to overlap.
Keywords
Climate change, Hybridization, Range distribution, Spartina maritima, Spartina densiflora