A new study published in the journal "Nature Plants" has discovered a third way that trees can adapt to climate change: through hybridization. Hybridization occurs when two different species of plants interbreed, producing offspring with a mix of traits from both parents. This can lead to the rapid evolution of new adaptations, as the offspring may inherit advantageous traits from both species.
The study, led by researchers from the University of California, Berkeley, focused on two species of oak trees that are found in the Mediterranean region: the cork oak (Quercus suber) and the holm oak (Quercus ilex). These two species have very different adaptations: the cork oak is well-adapted to drought conditions, while the holm oak is more tolerant of cold temperatures.
The researchers found that these two species can interbreed and produce fertile offspring. The hybrid offspring showed a range of traits, including some that were intermediate between the two parents and others that were unique to the hybrids. For example, the hybrids were more tolerant of both drought and cold than either of the parent species, and they also had larger leaves.
The researchers believe that the hybridization between these two species of oaks may have helped them to adapt to the changing climate of the Mediterranean region. As the climate has become warmer and drier, the cork oak may have been able to persist by hybridizing with the more drought-tolerant holm oak. This hybridization may have also helped the holm oak to expand its range into areas that were previously too warm for it.
The study provides new evidence that hybridization can play an important role in the adaptation of trees to climate change. This suggests that conservation efforts should focus on protecting not only individual species, but also the genetic diversity within species and the potential for hybridization between different species.
