The Inner Life of Animals. Peter Wohlleben
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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.
Is there really only one way—the human way—to experience feelings intensely and perhaps consciously? Evolution is not the single-track process we sometimes think (or maybe hope) it is. And birds, some of which possess diminutive brains, are a prime example that there is more than one route to intelligence. Since the age of their ancestors, the dinosaurs, their development has followed a different path from ours. Even without a neocortex, they can perform mental feats of the highest order. In birds, a region called the dorsal ventricular ridge oversees similar tasks and functions as our cerebral cortex. In contrast to the human neocortex, which is built up of layers, the equivalent area in the bird brain is made up of small clumps, a fact that fed long-standing doubt that it could perform a similar function.15 Today we know that ravens and other species that live in social groups can match, and in some cases even exceed, the mental prowess of primates. This is further proof of science’s practice of arguing too cautiously when in doubt about feelings in animals, denying them many mental capacities until there is positive proof that they possess them. Instead, couldn’t we simply (and just as accurately) say: “We don’t know”?
Before I end this chapter, I would like to introduce you to one more creature in our woods, an organism that is mindless in the truest sense of the word. Sometimes you can find it on rotting wood, where it forms a small, bumpy, yellow mat. It’s a fungus. Hold on a moment. Isn’t this a book about animals? Well, in the case of this fungus, science is not exactly sure which category it belongs to. It’s difficult enough with normal fungi, which form a third kingdom of living things in between animals and plants, because they cannot be clearly assigned to either category. Like animals, fungi subsist on organic substances from other living beings. In addition, their cell walls are made of chitin, like the exoskeletons of insects. And the slime mold that creates that yellow mat on dead wood can even move. At night, like gelatinous jellyfish, these organisms are capable of slithering out of the glass lab containers where they are temporarily confined. Today, science is moving them out of the realm of fungi and edging them a step closer to animals. Welcome to this book.
Researchers find some kinds of slime molds so interesting that they regularly observe them in the laboratory. Physarum polycephalum, with its somewhat awkward Latin name, is just such a customer, and it loves rolled oats. Basically, the creature is one giant cell with countless nuclei. What researchers are now doing is placing these slimy unicellular organisms in a maze with two exits and putting food at one