Study Raises Alarming Stat About the World's Plants

"Most people can name a mammal or bird that has become extinct in recent centuries, but few can name an extinct plant," says Aleys Humphreys, co-author of a gloomy new study on the fate of the planet's plants. Here, then, are three plants that have disappeared in the last 250 years or so: the Chile sandalwood (which had been sought for its aromatic wood), the Banded Trinity (notable in that it spent most of its life underground), and the St. Helena olive tree, reports CNN. Some highlights of the study by researchers at the Royal Botanic Gardens, Kew, and Stockholm University:

• The big number: At least 571 plant species have gone extinct since 1750, more than twice the number of extinct birds, mammals, and amphibians combined in the same span, reports the BBC.
• Alarming rate: Since 1900, three plant species a year have disappeared, a rate 500 times higher than would be expected naturally, reports Nature.

• A bright spot: Researchers also found that 430 species once considered extinct were subsequently rediscovered. However, the new study is so meticulous that the figure of 571 extinct plants is seen as rock solid.
• Even worse? "It is way more than we knew and way more than should have gone extinct," says researcher Maria Vorontsova. "It is frightening not just because of the 571 number but because I think that is a gross underestimate." Thousands of species are on the brink, and others may already be extinct but are awaiting confirmation.
• Hawaii: The US state has the unwanted distinction of having the most extinctions at 79, followed by the Cape provinces of South Africa at 37. Generally speaking, plants on islands and in the tropics were most likely to disappear, while trees, shrubs, and other woody perennials were the most likely type of plants to vanish.
• The culprit: Human destruction of natural habitats is seen as the main reason. For example, a researcher tells the Guardian of scouring Madagascar for a rare grass, Sartidia perrieri. "In the places where it would be growing, there are cattle grazing, regular fires, and people growing rice."

(More plants stories.)