Today's story begins with a weird picture of a man in a strange latex mask with a dead crow in his hand.

in fact, this is a scientific study. Through it, we can understand the excellent danger judgment ability of Corvidae birds.

We humans always pay special attention to similar corpses, which can arouse people's sense of fear. This is a very reasonable response: after all, factors that can lead to similar deaths can also threaten our own safety. The researchers found that crows also have the ability to judge danger by their own kind of death. There is no need to see any violence or the process of death, just seeing the dead is enough to make them vigilant and list the humans who appear together as "dangerous people". As long as they have met once, the crows can remember the face of the "dangerous person" and warn him and drive him away.

to verify this, use the weird-looking experiment in the photo above. The researchers put on different masks and played the roles of "good guys" and "bad guys" to show Corvus brachyrhynchos. The "good guys" provide food to the birds every day, while the "bad guys" appear in front of other crows for 30 minutes with a dead crow (actually a specimen of an animal).

(at Marzluff Lab, these latex masks have contributed to several crow studies. They even have names, starting clockwise from the top: Hiroo, Micheal, Vivian, and Joe)

results, although the crows do not see the process of death, but the crows quickly associate dead companions with danger, not only avoiding areas where food is available, but also shouting and driving away "dangerous people" in groups. Later, when the experimenter wearing the "bad guy" mask reappeared, even if he had no dead crows on his hands, he was still wary of the crows. If the "bad guy" appears with the red-tailed bird of prey (still a specimen, placed on a branch), the crows will be more alert, which is their known enemy.

(a crow that saw the dead and shouted)

and if the experimenter had a dead pigeon in his hand, the crow would not react at all-not only that, the pigeons next to him did not react either. This shows that crows are really special, they can understand the death of their own kind, and they will associate it with their own danger, and they can remember the face of the "bad guy" only once.

so why do you have to use such a weird mask? Because crows really hold a grudge! Not only can they tell people's faces, but they can even remember years. If the experimenter who plays the "bad guy" reveals what he really is, he may not be able to hang out in this area. He will be harassed by crows when he goes out every day.

(at the same time, in order to avoid being harassed by curious passers-by, they also put up the sign "Crow Research")

in short, crows are really smart birds, and remember not to mess with them-- because they will really remember you!

Wear stunning prom dresses for petite figures and flatter your body. We have a huge range of styles and cuts to choose from.

PS: remember faces only once. I think this level is much higher than my _ (: reading "∠) _

. This information comes from a study published in 2015.

Photo Source: https://www.sciencefriday.com/segments/crows-a-bird-thats-not-bird-brained/

original thesis:

http://www.sciencedirect.com/science/article/pii/S0003347215003188?np=y