Approximately 4.5 billion years ago, the land surface of our planet was barren and devoid of life.
It took another 2 billion years for the first single-celled organisms to appear in the ocean, including the first algae Grypania spiralis, which was about the size of a 50-cent dollar coin.
Plants made up of many cells have only been around for about 800 million years. To survive on Earth, plants had to protect themselves from ultraviolet radiation and develop spores and then seeds that would allow them to disperse more widely.
These innovations helped them become one of the ways of life most influential of the planet. Today they are found in all major ecosystems, and scientists describe more than 2,000 new species each year.
David Attenborough’s new documentary, The Green Planet, focuses his attention on plants and their ability to inspire us. In just one recent example, engineers have successfully copied the shape of winged maple seeds to design new wind turbines.
Plants hold many secrets that scientists have yet to discover. But here are five discoveries that helped us see our distant green cousins in a new light.
1. Plants “talk” to each other
Of course, plants don’t have vocal cords, so they can’t speak like us. But they do use chemical and electronic signals to coordinate responses to their environment.
When plant cells are damaged, like grass cut by a lawnmower, they release protein fragments that can be detected by surrounding plants.
It’s like a neighborhood watch system: when one plant is damaged, others are notified that danger is nearby. This can trigger an immune response or other defenses.
Similarly, plants can detect pollinators in their vicinity and release chemicals to attract them. These signals cause plants to be very complex communicators.
2. Plants can move
In his seminal book “The Power of Movement in Plants,” published in 1880, Charles Darwin described the ability of plants to move away from or toward light.
Scientists call this phototropism. It is now known that plant movements are not only guided by light, but also by water, nutrients, and in response to grazing animals and competition from other plants.
Plants can seem frozen in place, meant to stay where their seeds germinate. But in fact, plants are constantly adjusting their leaves, roots, and stems to improve their chances of survival.
For example, the parts of the stems that remain in the shade elongate to ensure that the plant grows towards the light in a process mediated by hormones. Roots show the opposite effect, causing them to grow away from light.
In some extreme cases, plants can even move through a forest whole. Nomadic vines grow upwards from the bottom of a tree trunk and then break out of the ground.
Later they take aerial roots and descend again, which allows them to move between the trees.
3. Plants can grow in space
Crossing space and living on another planet is something that humanity has been imagining for a long time, but another with the same environment as Earth has not yet been found.
We know that plants are experts at modifying environments to suit the needs of more complex life. When the first forests began to photosynthesize, they oxygenated Earth’s atmosphere and removed CO2, making the planet more habitable.
Could growing plants on distant planets make them better suited to our needs?
During the space race between the USSR and the United States in the 1950s and 1960s, scientists studied how plants grow and develop in space. So far, experts have grown 17 different species in specialized chambers, including corn, wheat, tomatoes and lettuce.
Major challenges remain for growing Earth’s plants outside our atmosphere, including radiation during spaceflight and differences in gas movements in space compared to Earth.
If you think it’s hard to keep a plant alive at home, try doing it in space.
Transforming a planet to make it habitable for human life remains difficult, but all the progress with plant science in recent years makes it a achievable goal. We might even get to see it.
4. One of each 10 plants grows on another plant
At tens of meters tall, they are some of the tallest organisms on the planet. Sequoias, for example, can reach up to 10 meters in height.
Scientists began to study the high treetops by training monkeys or employing expert climbers to collect samples. Some even used shotguns to shoot down samples.
It was not until the 1980s that canopy research became a scientific discipline in its own right, borrowing the technique of rope climbing from mountaineering.
Later, scientists began to use cranes, balloons and drones.
But why risk your life to climb a tree? Whats going on there?
It is estimated that until 80% of species live their entire lives in the canopy.l forest or tree (the habitat that make up the treetops).
And one in 10 of all known vascular plant species – species that use vein-like vessels to transport water and nutrients throughout the body – grow on top of other plants.
They are called epiphytes and are not parasites, but use their host as physical support. This gives them an advantage over plants that grow in the understory, where light is scarce.
Most orchids grow on trees, and a single tree can support up to 50 species of epiphytes. These epiphytes often produce more leaves than their host tree.
5. Plants can indicate global changes
Organisms are very sensitive to changes in their environment and plants in particular have been used to detect these changes for centuries. When the leaves begin to change color in the fall, they usually herald the arrival of colder, darker months.
Certain species of ferns are particularly vulnerable to changes in their local climate. Transparents grow in the shady regions of tropical forests, usually near the bases of trees or on moist rocks.
They depend on water and low temperatures, and are good indicators of the approaching drought and rising temperatures.
Since the 1980s, the global average temperature has been rising as a direct result of burning fossil fuels such as carbon, which was deposited by plants millions of years ago during the early formation of forests.
We live in a time of change and understanding how plants respond to climate changes can help us prepare for the future.
*Sven Batke He is a professor of BiologyEdge Hill University College, UK.
*This note was published on The Conversation and reproduced here under a Creative Commons license. Click here to read the original version (in English).
It may interest you:
* The garden where all its plants could kill you just by touching them
* 5 plants to decorate your home whose presence helps combat stress and anxiety
* The 7 basic gardening tips from experts when you are a first timer
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