Chilean Crocus Source: Stockholm University

NEARLY 600 PLANT species have become extinct in the past 250 years – more than twice the number of birds, mammals and amphibians combined.

A new study conducted by the Royal Botanic Gardens, Kew, and Stockholm University combined global analysis of all plant extinction records from across the world and found that plant extinction is occurring up to 500 times faster than ‘natural’ rates of extinction.

Published today in Nature Ecology & Evolution, the revealing study gathered data from fieldwork, literature and herbarium specimens to show which plants species have become extinct.

The study found that 571 plant species have disappeared in the last two and a half centuries, more than twice the number of birds, mammals and amphibians – a combined total of 217 species.

The Chile sandalwood, for instance, was a tree that grew on the Juan Fernández Islands which lie between Chile and Easter island.

From around 1624, the tree began to be heavily exploited for the aromatic sandalwood and by the end of the 19th century most of the trees had been cut down.

The last tree was photographed on 28 August 1908 on Robinson Crusoe island by Carl Skottsberg. The tree has not been seen since on that island.

“Most people can name a mammal or bird that has become extinct in recent centuries, but few can name an extinct plant,” Assistant professor at the Department of Ecology, Environment and Plant Sciences at Stockholm University Dr Aelys M Humphreys said.

“This study is the first time we have an overview of what plants have already become extinct, where they have disappeared from and how quickly this is happening.”

“We hear a lot about the number of species facing extinction, but these figures are for plants that we’ve already lost, so provide an unprecedented window into plant extinction in modern times.”

‘All life on earth’

The study found that the highest rates of plant extinction to be on islands, in the tropics and in areas with a Mediterranean climate – regions which are home to “many unique species vulnerable to human activities,” he study notes.

Another species - St Helena olive tree – was first discovered in 1805 on the island of St Helena in the South Atlantic Ocean.

One elderly tree survived until 1994, from which Kew and local conservationists were able to collect cuttings before it died.

“Plants underpin all life on earth, they provide the oxygen we breathe and the food we eat, as well as making up the backbone of the world’s ecosystems – so plant extinction is bad news for all species,” Dr Eimear Nic Lughadha, Co-author and Conservation Scientist at Royal Botanic Gardens, Kew has said.