The Inner Life of Animals. Peter Wohlleben

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СКАЧАТЬ Ouch! But all that proves is that a dull feeling of pain is within the realm of possibility. And so Braithwaite poked needles into the areas she had identified, which caused a reaction in the fishes’ hindbrain, which is exactly where pain stimuli are processed in people. That should be enough to prove that fishing injuries cause fish to suffer.

      But what about emotions? Let’s consider fear. In people, fear arises in the almond-shaped amygdala. For a long time that was not proven, even though it was suspected. It wasn’t until January 2011 that scientists from the University of Iowa published a paper about a woman identified as SM. SM was afraid of spiders and snakes—until the cells in her amygdala died after a rare illness. That was, of course, tragic for SM; however, it offered researchers a unique opportunity to investigate what happens when this organ is lost. They took SM to a pet shop and confronted her with the animals she feared. The woman could now touch the animals, something she could never have done before, and she reported that she simply felt curious about them and no longer felt in the least bit frightened.⁹ And so the seat of fear can now be precisely located in people. But what about fish?

      Manuel Portavella García and his team at the University of Seville have indeed found comparable structures in the outer areas of the fish brain, a place where no one had looked before. (In people, the fear center lies deep inside the lower part of the brain.) First, the researchers trained goldfish to swim quickly away from one corner of their tank as soon as a green light came on. If they failed to do this, they got an electric shock. Then, the researchers disabled a part of the fishes’ brain known as the telencephalon. It corresponds with our fear center, and switching it off had the same result as in people: from then on the goldfish were no longer afraid of the green light and they ignored it. From this, the researchers concluded that fish and terrestrial vertebrates have inherited the same brain structures from common ancestors that lived more than 400 million years ago.¹⁰

      It follows that all vertebrates have had the hardware for emotions for a very long time, but does that mean that animals feel things the same way we do? Much points in that direction. Scientists have even found oxytocin in fish, the hormone that not only brings joy to mothers, but also strengthens the love between partners. Joy and love in fish? We’re not going to be able to prove that, at least not in the foreseeable future, but if there’s any doubt, why do we assume they are guilty as charged? Scientists have spoken out against emotions in animals for so long that their view is mostly accepted, but wouldn’t it be better to give animals the benefit of the doubt to be sure that they are not suffering unnecessarily?

      In the preceding chapters, I have purposely described emotions as we experience them. This is the only way we might be able to understand what’s going on inside animals’ heads. But even if the structures in their brains differ from ours and these differences mean that they probably experience things differently, that certainly doesn’t mean that emotions in animals are inherently impossible. It simply means that it is more difficult for us to imagine what their emotions might feel like. Take the fruit fly, for example, whose central nervous system is made up of 250,000 cells, making it one four-hundred-thousandth the size of ours. Can such minute creatures with such a limited capacity up top really feel anything? Can they even be said to possess consciousness—this being, of course, the pinnacle of achievement. Unfortunately, science is not yet advanced enough to be able to answer this question, partly because the concept of consciousness cannot be clearly defined.

      The closest we can get to a definition is that consciousness involves thinking and reflecting on things that we have experienced or have read about. Right now, you’re thinking about what you’re reading, and so you possess consciousness. And at a very basic level, the conditions necessary for consciousness have been discovered in the tiny brains of fruit flies. The flies are constantly barraged by stimuli from the external world, just as we are. The smell of roses, car exhaust, sunlight, a breath of air—all are registered by a variety of unconnected nerve cells. So how does a fly filter out from this flood of sensations what is most important so that it can stay out of danger and not miss out on a particularly tasty morsel? Its brain processes the information and ensures that different areas coordinate their activities, strengthening certain stimuli. And so what is of interest stands out from the general noise of thousands of other impressions. The flies, therefore, can focus their attention on specific things—just as we can.

      Fruit flies’ eyes are made up of about six hundred individual facets. Because these tiny insects dart around so quickly, their eyes are bombarded by a huge number of images per second. This seems like an impossibly large amount of data to process, but the flies must do this if they are to survive. Anything that moves could belong to a voracious predator. Therefore, the fruit fly brain leaves all static images blurry and focuses exclusively on moving objects. You could say that the tiny tykes are stripping things down to the bare essentials, an ability that you surely would not have expected these little flies to have. By the way, we do something similar. Our brain doesn’t allow all the images we see to make it through to our consciousness. It only lets the important ones through. Does that mean flies have consciousness? Researchers won’t go that far; however, it is clear that flies can at least actively focus their attention on what matters most to them.¹¹

      Let’s return to variations in brain structure between species. The basic organ is certainly present even in lower vertebrates, but for the quality of feelings we experience, more is needed. You read over and over again that intense emotions of which the subject is consciously aware are only possible with central nervous systems like ours. The stress lies on the words “consciously aware.” The grooves and ridges in our brain occur in its outermost layer, the neocortex, which is the most recent part of our brain to evolve. This is the seat of self-awareness and consciousness, the place where thinking happens. And the human brain has more of these cells than any other species. The crowning achievement of creation sits there right under our skull. It follows that all other creatures must be less aware of the constellation of emotions we experience and cannot be as intelligent as we are, right? Consider comments made by Germany’s first professor of fisheries and fishing, Robert Arlinghaus, co-author of a study on pain in fish for the German government. In an interview with the German magazine Spiegel Online, he stressed that fish cannot experience pain like we do from the injuries they suffer when they are caught because they do not have a neocortex and therefore they can have no conscious awareness of pain.¹² Apart from the fact that other scientists do not agree with him (see below), this sounds to me more like a rationalization of his hobby than a reasoned, objective scientific opinion.

      Gourmets advance a similar argument every year at Christmas when it’s customary to load the table with tasty crustaceans, and Der Spiegel (the print sister magazine to Spiegel Online) has reported on this, as well.¹³ The poster child for the spectrum of shellfish is the lobster, which is served up on a platter as a status symbol after being boiled bright red. Boiled alive, that is. Whereas vertebrates are killed before they are cooked, it’s perfectly acceptable to throw crustaceans into a bubbling pot with all their senses intact. It can take minutes until the heat makes its way completely inside the animal, destroying its sensitive nerve endings. Pain? How can that be? Crustaceans don’t have a spinal cord, and that means they are incapable of feeling pain. Or, at least, that is what people say. Their nervous system is configured differently from ours, and it’s even more difficult to prove pain in crustaceans than it is in species that have an internal skeleton like we do. Scientists arguing on behalf of the food industry insist that the animals’ reactions are nothing more than reflexes.

      Professor Robert Elwood at Queen’s University in Belfast disagrees. “Denying that crabs feel pain because they don’t have the same biology is like denying they can see because they don’t have a visual cortex [the part of the brain responsible for sight in people].”¹⁴ Apart from that, pain is a component in reflex actions, as you can easily test for yourself if there’s an electric fence nearby. If you put your hand on it and get an electric shock, you have no choice but to pull back right away, whether you want to or not. It’s pure reflex on your part, something you do without a moment’s thought, but that doesn’t make the electric shock any less painful.

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