Feral Date Palms Discovered on Cape Verde Island Spark New Research

Phoenix dactylifera, a commercial date palm species, has contributed to a significant botanical discovery on Cape Verde, an island nation off western Africa's coast. On February 11, researchers reported groundbreaking findings in the new journal Plants, People, Planet. They discovered that wild, feral descendants of domesticated Phoenix dactylifera are thriving across the microclimates of Cape Verde’s hot, arid, and sandy terrain. This discovery has exciting implications for breeders of the commercial species, allowing them to tap into previously unexplored genetic diversity.

Wild, self-sown feral date palms do wonderfully well in Cape Verde, adding a glorious touch to the islands’ vegetation. This unique ecosystem is home to six species of native trees. One of these is Phoenix atlantica, the Cape Verde date palm. This tree, called the name “Reverend Naturalist” in English, is one of only three native trees that do not grow rampant outside the socio-ecological archipelago. Culturally and ecologically important, Phoenix atlantica is a cornerstone of the natural heritage of Cape Verde. Despite all that, this remarkable species remains critically endangered.

Jerónimo Cid Vian is an evolutionary biologist currently based at the Royal Botanic Gardens, Kew in England and Bangor University in Wales. He’s been leading the way in understanding this dangerous phenomenon. He extracted and sequenced DNA samples from all of Cape Verde’s date palms. Among these samples was a specimen collected in 1934 by a French botanist that went on to help define the species Phoenix atlantica. His research uncovers how some date seeds escaped from their domesticated date palm oasis. This meant they had successfully found a home in the wild.

"One or a few date seeds escaped from their grove," said Jerónimo Cid Vian, highlighting the origins of these feral offshoots.

This discovery prompts a broader conversation among taxonomists, conservation experts, and the local community regarding the implications of these feral date palms. Deciphering the genetic code behind these plants can unlock important adaptive traits. We can use these traits to improve their commercial date palm cultivation.

"Like much of real-world biology, the species question gets 'more messy than what we are taught in school — and I love that,'" remarked Jerónimo Cid Vian, reflecting on the complexity and intrigue of biological classification.