【推荐1】If you travel to a new exhibit at the San Francisco greenhouse of Flowers, you will have a chance to see some meat---eating plants. Take bladderworts, a kind of such plant, for example. They appear so small and grow in a quiet pool. But these are the fastest---known killers of the plant kingdom , able to catch a small insect in 1／50 of a second using a trap(陷阱) door!

Once the trap door closes on the animal falling into it, the enzymes(酶)similar to those in the human stomach slowly digest the insect. When dinner is over, the plant opens the trap door and is ready to trap again.

Meat－eating plants grow mostly in wet areas with soil that doesn't offer much food value. In such conditions these amazing plants have developed insect traps to get their nutritional(营养的)needs over thousands of years. North America has more such plants than any other continent.

Generally speaking, the traps may have attractive appearance to fool the eye, like pitcher plants, which get their name because they look like beautiful pitchers ( a container like a bottle) full of honey.

The Asian pitcher plant, for example, has bright colors and an attractive half－closed cover. Curious insects are attracted to come close and take a drink, then fall down the slippery wall to their deaths.

Some of these pitchers are large enough to hold two gallons (7.5 liters). Meat－eating plants only eat people in science movies , but sometimes a bird or other small animals will discover that a pitcher plant isn't a good place to get a drink.

【推荐3】Bottlenose dolphin moms adapt their individually special whistles (口哨) when their babies are nearby. This “parentese” might increase attention, bonding (联系) and vocal learning in babies, as it seems to do in humans.

During the first few months of life, each common bottlenose dolphin develops a unique tune, or signature whistle, similar to a name. The dolphins shout out their own “names” in the water “likely as a way to keep track of each other,” says marine biologist Laela Sayigh. But dolphin moms seem to adjust that tune in the presence of their babies, which tend to stick by mom’s side for three to six years.

Sayigh and colleagues analyzed signature whistles from 19 female dolphins both with and without their babies close by. Audio recordings were got from a wild population that lives near Sarasota Bay, Fla., during catch-and-release health assessments that occurred from 1984 to 2018. The researchers examined 40 examples of each dolphin’s signature whistle, confirmed by the unique way each vocalization’s frequencies change over time. Half of each dolphin’s whistles were voiced in the presence of her baby. When youngsters were around, the moms’ whistles contained,   on average, a higher maximum and slightly lower minimum pitch(音高)compared with those voiced in the absence of babies, contributing to an overall widened pitch range.

These whistle adjustments echo baby talk because human caregivers use real words and language, just with certain inflections (变调), Sayigh says. Formally called child-directed communication, these inflections typically involve higher pitches and a wider pitch range, like what was observed in the dolphins. “Bottlenose dolphins are a main candidate for child-directed communication,” says Quincy Gibson, a marine mammal behavioral ecologist. Similar to humans, these dolphins form strong mother-baby bonds and learn vocalizations.

But to confirm this study’s results, scientists should analyze signature whistles of freely swimming, uncontrolled dolphin moms, notes Gibson. “We do need to look at this question in more natural and undisturbed conditions.” Still, Gibson says, “The idea that there might be similar forces driving parentese in such different species is just really cool.”

【推荐3】Artificial intelligence (AI) could help stop one of the biggest dangers to the Great Barrier Reef(大堡礁), amazingly saving huge areas of coral(珊瑚) from a harmful starfish. Google has teamed with scientists from the CSIRO to create AI software(软件) that could pick out the dangerous starfish, which is one of the natural wonder’s three biggest killers.

The new way, using footage from an underwater camera to recognize starfish outbreaks on the Queensland reef, takes the place of an old method and early results show as well as cutting down man’s work, the new software has the advantage of correctly picking out more of the dangerous life on coral, stopping damaging outbreaks before they occur.

Professor Russ Babcock, an expert with CSIRO, said Google’s AI technology, developed over 18 months, could be trained to find out starfish more easily than the old method developed in the 1970s. “We used to send out divers to count the starfish one by one. Now we just look at the images collected and the program can find 20 at a time,” he said.

Google CEO Sundar Pichai said he was excited about the company’s effort put into the reef project. “We have put a lot of effort into the engineering in Australia and we will continue to do more work around AI there,” he said. “There are other good ideas about the technology and you will see us build on it. Our goal with our AI research teams is to strike partnerships with other groups, like universities and governments, to give its full play.”

Professor Babcock said the AI software, which would be put into use on other reefs worldwide, was not the only solution to the starfish affecting the Great Barrier Reef, but one that could have an wide application.