Many animals depend upon sound to find food, detect enemies and communicate with one another. These species understandably suffer when loud motorways cut through their habitats. Some deal with by singing more loudly, some change the timing of their calls to occur when fewer people are driving, others just move to quieter places.

All of these actions come with significant costs attached and scientists have long documented the ecological damage caused by noise pollution. It has always been assumed, however, that noise is a problem unique to animals. But a new study by Ali Akbar Ghotbi-Ravandi, a botanist at Shahid Beheshti University in Tehran, has showed that plants suffer too.

That plants can be hampered indirectly by noise pollution has never been in doubt. Since most flowering species depend upon pollinators (传粉者) and most fruit-bearing species need animals to spread their seeds, it is obvious that if these animal partners are harmed by noise then their botanical counterparts will do badly, too. What has remained unknown is whether or not plants themselves suffer directly from noise pollution.

Sounds are pressure waves transmitted through gases, liquids and solids, Scientists have previously assumed that plants may be able to sense these waves as they are struck by them. A number of experiments have confirmed this in recent years—plants bombed with ultrasound (超声波) in the lab have shown a range of bad responses including the expression of stress-related genes, slow growth and reduced production of seeds.

Yet bombing plants with ultrasound is not the same as growing them in the presence of actual traffic noise. To this end, Dr Ghotbi-Ravandi decided to set up an experiment to study precisely this question.

It seems we can’t get off the planet fast enough. Two thirds of NASA’s money is spent on manned space exploration, and that number will grow with the USA’s decision to send a man to Mars in 2037. We’ve seen all there is to see on Earth, right? Wrong. The final place is here, under the surface of the sea.

Heading down into the ocean, human limits are quickly reached. At 200 metres, the water is as black as a moonless night. Most nuclear submarines (核潜艇) would implode (内爆) before they reach 1 km down. At 3 km — still less than the average depth of the ocean — there’s a good chance that you’ll discover a new species. The deepest­diving whales go no further. At the very bottom, about 11 km down, lies the Challenger Deep, the deepest part of the Mariana Trench in the Pacific Ocean. Eighteen humans have walked on the Moon, but only three have seen the Deep with their own eyes.

Yet things live down there. Big things. A very loud sound was once heard and scientists suggested that it was produced by an animal bigger than a blue whale, the largest creature known on the planet.

In the late 1990s, a deep­water submarine was dropped in the Southern Ocean, and passing 4,000 metres, it discovered something huge passing under it. Surprised? Don’t be. The ocean covers 70% of the planet’s surface and we’ve studied less than 5% of it. We know more about the dark side of the Moon than about the bottom of the sea.

One reason that we explore space is to find evidence of other life forms. The search for life outside of Earth is important, but robots can look under the dry rocks of Mars better than humans. They’re absolutely important for doing ocean research too, but they can’t look under the sea. The cost of exploration is rising, but the results would benefit all our lives. Understanding the oceans will help us find new sources of food, drugs and energy.

Perhaps now it's time to begin a new period of sea exploration. Manned exploration of space is science fiction (科幻小说). The adventure of the deep sea is science fact.

Fossils discovered in Liaoning province have challenged the theory that the Archaeopteryx is the earliest known bird.

Research of the fossils led by Pascal Godefroit and his team from the Royal Belgian Institute of Natural Sciences revealed that the dinosaur bird Aurornis xui, like the Archaeopteryx, existed nearly 150 million years ago. Godefroit told British-based Daily Mail, “The evolutionary development shows that dinosaur birds were already diversified in northern China during the Middle-Late Jurassic.”

The study, published in the journal Nature, showed that Aurornis xui was 50 cm in length and had tiny teeth used for hunting and defense, similar to other dinosaurs. Godefroit said the results support a “single origin of powered flight”, which suggests that all dinosaurs that became birds took flight around the same time, and eventually lost hunting and defensive features, like teeth, during adaptation.

Hu Dongyu, a professor at Shenyang Normal University, pointed out that fossils of some dinosaurs show that the legs initially had long feathers, which suggests they assisted wings in flight. “But the long feathers on the legs degenerated as the wings became strong enough. This is not the first time that fossil evidence has showed the evolution path from dinosaurs to birds,” said Hu. “The initial question was whether these dinosaur birds existed before the Archaeopteryx, but as we dig deeper into them, the age became irrelevant. And now the bone of contention is whether all these dinosaur birds are dinosaurs or birds.”

One fossil, found in Liaoning in 2009 and studied by scientists led by Xu Xing from the Chinese Academy of Sciences in Beijing, showed that the earliest dinosaur bird was Anchiornis huxleyi, a flying dinosaur that lived 160 million years ago. Another fossil studied by Xu and his colleagues, also believed to be a dinosaur bird, was named Xiaotingia zhengi. “Aurornis xui, Anchiornis huxleyi and Xiaotingia zhengi are similar dinosaur bird fossils,” Hu added. “The earlier research suggested that all dinosaur birds were dinosaurs, not birds. However, recent research suggests the opposite. So there is a long way to go to draw a conclusion.”