Experimental decoding story

Seek out the solution for the vultures that can't smell their own food.

Although vultures do not belong to the group of 'lovely' birds in many people's eyes, they have an irreplaceable role in the ecosystem.

Can be likened to vultures as hard-working students of the natural environment, clearing animal corpses in the pasture. From the nineteenth century, farmers in Western countries like Britain and the United States became more and more interested in the usefulness of vultures.

At that time, everyone thought vultures sought food with their sense of smell. They said that the stinking dead animal bodies would lure hungry vultures to beat the cup.

However, John James Audubon (1785-1851) - the famous naturalist of French Americans did not think so.

Picture of John James Audubon - naturalist and artist.He drew a collection of birds in North America.

Audubon once went into the forest to see a vulture. It was only when he came very close, the new bird startled and flew away while it was supposed to smell people from far away. Since then, the scientist began to doubt the olfactory ability of this animal.

He decided to try an experiment. Audubon used deer skin around the haystack, then decorated his head, eyes and parts to mock a deer in the pasture.

Amazingly, a vulture appears and pecks at the 'deer'. If the vulture could smell the smell, it would not be fooled so easily.

Audubon tried another experiment. He took a decomposing dead pig's body in the middle of the meadow but covered the branches.

Although the area has many vultures flying, none of them discover this sumptuous meal. Audubon surmised that the olfactory ability of vultures was exaggerated by humans. According to him, vultures use their keener eyes than use their noses to get food.

A swarm of black vultures in Texas, USA

In 1826 Audubon gave a presentation about his findings in London. However, he was fiercely opposed.

British naturalist Charles Waterton also remarked that Audubon's point of view is silly and deserving. Still, Audubon is not shaken.

Experts in the field of study decided to meet in Charleston, South Carolina (USA) - where many vultures live.

They tried an experiment like this. A hired painter painted a picture of a wounded sheep's dead body - the perfect meal for vultures. The picture is taken out of the pasture.

At the same time, people prepare a pile of stinking meat and hide under a small wooden board, so that vultures can enter to get food.

The air could get into the wood and spread the smell of rancid meat all around. They put this hidden pile of meat in the way the picture of the fake meal was only about 5 meters.

The experiment began and to everyone's surprise, the vultures flew down and dripped into the picture of the dead sheep.

The naturalist learns Jon Bachman - who designed this experiment, realizing that even though the stench of meat is close by, no vultures will ever come near.

Black vultures are waiting to eat fish at a harbor in Ecuador, South America

So Audubon won the debate with scientists. By practical experiments, the popular belief that vultures seeking food has been rejected.

Instead, sight is the main tool that helps this animal detect prey. It can be seen that if there is no empirical science, our understanding of nature and things in general will be full of errors.

Aura cathartic vultures can use their sense of smell to feed, unlike their black vultures.

However, it should be noted that the above experiment is only true for black vultures. Scientists later discovered that some other vultures such as aura vultures can use their sense of smell to find food.

Interestingly, in the 1930s, Texas oil engineers took advantage of this species' delicate sense of smell to detect cracks in the oil pipe.

They pumped an aromatic chemical into the oil pipe and if there was a gap, the aura cathartes would fly around, informing the engineers of the problem.

* The article is based on the views of Robert Krulwich, published on the NPR science page.