Most animals are known to grab at least 40 winks at some point in the day, but it seems trees also drop off to'sleep' during the hours of darkness. Researchers have found that trees relax and let their branches droop when the sun goes down. A collaboration of researchers from Austria, Finland and Hungary used laser scanners on fully grown trees to measure their'sleep movement'. Scientists have found that trees appear to'rest' at night. The figure on the left depicts the tree at night, while the mirrored figure on the right depicts the same tree during the day.
It might seem as though trees spend most of their lives standing still – but, according to new research, they do a lot more moving than you'd think. Scientists have discovered the subtle'heartbeat' of trees and shrubs, using terrestrial laser scanning to measure the overnight movement of branches and leaves. While only some trees in the study were shown to follow a'sleep cycle,' in which their branches lowered at night and returned to their daytime position hours later, the researchers found that all of the trees displayed minute, periodic pulses. The discovery suggests trees are pumping water, the experts say. Scientists have discovered the subtle'heartbeat' of trees and shrubs, using terrestrial laser scanning to measure the overnight movement of branches and leaves.
They don't snore, but might creak during their slumbers. For the first time, trees have been shown to undergo physical changes at night that can be likened to sleep, or at least to day-night cycles that have been observed experimentally in smaller plants. Branches of birch trees have now been seen drooping by as much as 10 centimetres at the tips towards the end of the night. "It was a very clear effect, and applied to the whole tree," says András Zlinszky of the Centre for Ecological Research in Tihany, Hungary. "No one has observed this effect before at the scale of whole trees, and I was surprised by the extent of the changes."
Urban trees are being robbed of sleep by streetlights, according to an influential German forester. Peter Wohlleben, author of'The Hidden Life of Trees', said city lights should be switched off to help trees live for longer. He said that, like humans, 'they also have to sleep at night'. Mr Wohlleben likened trees in urban areas to orphans who have to grow without their network of support, claiming that light pollution makes city life even harder. Peter Wohlleben, author of'The Hidden Life of Trees', said city lights should be switched off to help trees live for longer and likened urban trees to orphans (stock image) Plants use light as a source of energy and information, according to research published in the Journal of Ecology.
Plants are much smarter than we give them credit for and even have tiny brains that decide the right moment to germinate, according to a new study. Researchers have found a group of cells function as a'brain' for plant embryos which can predict the weather and change their behaviour accordingly. Previous studies have shown plants can hunt out water and even learn from bad experiences, just like animals. Scientists showed that a small group of cells within the plant embryo operate in a similar way to the human brain. The'decision-making centre' in a plant called Arabidopsis, or thale cress, contains two types of cell - one that promotes seed dormancy, and one that promotes germination.