Unlike well-trained dogs that are able to distinguish (辨别) between common orders like "sit" and "stay", some "Gifted Word Learner" dogs can associate objects with words.

One year ago, Shany Dror and her colleagues at Eötvös Loránd University in Hungary discovered that some dogs have an obviously excellent natural ability to acquire object names. To study this further — how many words they can learn in a certain period of time and whether they can still remember the words after an extended period — they looked for more "Gifted Word Learner" dogs online and, in the end, they found six qualified dogs.

The researchers sent each dog's owner six new toys. Owners then had six days to teach their dogs the names of the toys with their usual methods. These generally involved playing with the dog and each toy, often for just half an hour a day. At the end of the six-day learning period, the research team used online video conferencing to test the dogs' abilities to pick out each toy by name from a number of old and new toys. Each owner sat with their dog in one room and told them to fetch a given toy from a second room. All the dogs successfully brought back at least five of the six new toys. The team then sent another 12 new toys and repeated the process. All the dogs successfully brought back at least 11 of the toys.

Afterwards, half the new toys were stored for one month, and the other half for two months, and the dogs were tested again after each storage period. Five of the dogs remembered all the toy names after one month, and four dogs remembered all or almost all of them after two months.

Dror says these dogs, which are raised in the home like human children, provide an excellent animal model (模式) for studying the way humans acquire language. An animal model offers a basis of comparison for understanding which language-learning skills are specific to humans, and which aren't. "We want to understand what makes humans different," says Dror.

Throughout the world, there are about one thousand kinds of bats (蝙蝠), which are usually divided into two groups: Megachiroptere and Mricochiroptera. Their body lengths vary (变化) rather widely from 1.5 inches to 16.7 inches.

Bats are the only little mammal (哺乳动物) that can actually fly in the world, and it is safe to say they are very good at this skill using echolocation (回声定位) to find their way in the sky. Using echolocation bats are able to take sound waves to create a detailed map of the area around them.

Bats use the ability not only to know what may be in their way but also to hunt for food. Bats are active during the night, and they use nighttime to look for food. In fact, they can eat so many bugs (小虫) in one night as to make them flightless for a period of time. Bats not only eat bugs, but also feed on fruit and small birds. Many places have brought in bats to help as a choice instead of using pesticides (杀虫剂).

Anyone can build or buy a bat house to put up in the backyard. Building a bat house is easy and just a little care is needed to keep it. It could help deal with bugs each year. Bats stay together in these bat houses along with inside houses, buildings, trees and other places, and usually stay together in large numbers.

As you can see, bats are far from the scaring creatures. So, next time you see them, stop and think of the bugs and flies you will miss.

Show Some Love to the Ugly and Endangered

Let’s face it-not every animal is going to win a beauty contest. But all of them are important, and they all deserve a chance at survival. Let’s show a little love for some of the endangered species that may not be the prettiest, but need our help all the same.

Pallid Sturgeon(浅色鲟鱼)

The species has been around for more than 78 million years. These guys once shared the planet with dinosaurs. And sadly，they could be going the same way as their now fossilized(变成化石的)friends. Today, the last wild-born pallid sturgeons are nearing extinction. As humans built dams in the waterways these fish need to survive, they blocked the pallid sturgeon from being able to reach its breeding grounds.

California Condor(加州秃鹫)

The California condor sports a bare featherless head, the better to put into dead things without getting too dirty. With a wingspan of up to 9 feet, they’re one of the largest birds in the world. But due in large part to habitat loss, illegal shootings, and lead poisoning, by 1985 the entire known wild population had been reduced to just nine birds.

Northern Long-eared Bat

Few animals have as undeserved a bad reputation as bats do but they actually provide incredibly valuable services like pollination(授粉)or eating insects that could otherwise kill crops or make us sick.

North American bats like the Northern long-eared bat are being killed right now by a disease called “white nose syndrome”. This infection has lent new urgency to efforts to protect bat habitats and reduce other threats to their survival.

These are just three of a long list of endangered species that need our help-even if they aren’t always the ones that get the lion’s share of the spotlight. This Valentine’s Day, show some love for species like these.