On Monday night, I braved the post-blizzard snowscape to head to Brooklyn's beautiful Bell House for this month's Secret Science Club lecture, featuring Dr Diana Reiss of the Department of Psychology at Hunter College and the Biopsychology and Behavioral Neuroscience Program at the CUNY Graduate Center. Dr Reiss studies cetacean communication and cognition.
After a brief autobiographical introduction, detailing her career move from theatrical design to studying animal cognition, Dr Reiss introduced us to Tursiops truncatus, the common bottlenose dolphin. Dr Reiss described dolphins as true non-terrestrials- they have a totally aquatic lifestyle. They have big brains and complex social structures, and have been demonstrated to experience suffering. When Dr Reiss started studying animal cognition in 1979, not much was known about dolphin cognition. Her initial subjects were Delphi, the first dolphin she studied, and Circe, a dolphin captured at the age of four. After this brief introduction to her subjects, Dr Reiss digressed to state that dolphins need to be protected, and that wild dolphins should not be captured.
Delphi and Circe were trained to respond to hand signals, something which does not come naturally. One technique used in training animals is to give them a "time out" when they exhibit undesired behaviors. Circe was accustomed to eating fish which had been cut into sections, and preferred to eat the tail sections of mackerel which had had the spines removed from them. One one occasion, Dr Reiss gave Circe a mackerel tail with uncut spines and Circe responded by giving her a "time out". Dr Reiss decided to turn this anecdote into a study and learned that giving Circe uncut tails would lead to avoidance, which only occurred when the uncut fish tails were presented to her. Dr Reiss posed the question, "What do dolphins do with their big, highly encephalized brains?" She then noted that it was useful to see dolphins as partners, not merely subjects. Dolphin studies should be designed to enrich the dolphins, not only to study them. Also, dolphins should be protected as individuals, not just populations.
Dolphins are toothed whales, Odontoceti, as opposed to the baleen whales or Mysticetes (Dr Reiss gave us a pop quiz- which came first, the toothed whales or the baleen whales? Clearly, the toothed whales came first, as their ancestors were toothed, while the more 'derived' baleen whales have baleen, a novel structure, rather than the ancestral teeth). Dolphins have large complex brains- the average bottlenose dolphin has a brain that weighs 1,700 grams. The average human brain weighs 1,300 grams. Dolphins have bigger bodies than humans, though- in relative size, dolphin brains are second only to human brains. The brain to body size ratio is known as the encephalization quotient- humans have an EQ of 7, bottlenose dolphins have an EQ of 4.2, chimpanzees have an EQ of 2.3, orangutans 1.8, and gorillas 1.6. This number roughly describes how much bigger an animal's brain is than is needed for basic survival. Dolphin brains, like human brains, have a great degree of folding of the brain's surface. Dolphin brains also have two hemispheres, but these hemispheres operate differently than those of human brains. Dolphins, unlike humans, are voluntary breathers- living underwater, dolphins need to consciously breath. When dolphins sleep, one hemisphere of the brain remains conscious, while the other one rests- most of the time, both hemispheres are conscious.
Dolphins form highly complex societies. They exhibit culture, passing knowledge from individual to individual and from generation to generation- as an example, certain dolphin populations engage in tool use, even without hands, employing sponges to protect their rostra when they forage. Dolphins form fusion-fission societies, even though they form strong ties, groups continually break apart and come together. It is possible that large complex brains evolved in order to keep track of individuals in social networks. The best studies of dolphin social networks were conducted with Atlantic spotted dolphins (Stenella frontalis) in Bimini and Belize (I'm stymied linking here due to all of the 'swim with dolphins in Bimini' sites). Even though dolphins are non-handed, they are creative and manipulative- for example, they play with seaweed, not only with each other but with humans as well. One particular aquarium dolphin, Shiloh, was sometimes observed carrying a rock on her rostrum and once ringed an aquarium drain with rocks. Dolphins have also been observed blowing bubble rings with their blowholes and playing with them (WARNING: video features New Age-y music):
Dolphins are capable of anticipatory behavior and planning ahead. They engage in cooperative foraging and child rearing. They even discipline youngsters with thumps. Recently, bottlenose dolphins have been observed off the coast of Floridamaking 'corrals' of silt in which to entrap fish:
As an aside, I'd have to note that Florida dolphins are smarter than Florida man, but I digress.
In 1993, Dr Reiss led a team which created a dolphin keyboard in order to determine what dolphins would do when given choice and control. The keyboard had distinguishable shapes which the dolphins could use to request things. Each key of the keyboard produced a sound and each key dispensed a non-food reward- it was basically a vending machine for dolphins:
One of the purposes for the audible signal was to ascertain the role of imitation in vocal learning among dolphins. At three months of age, dolphins learn how to echolocate. The keyboard was introduced to eleven month old dolphins, which quickly imitated the signals on a spontaneous basis- agter about twenty exposures, the dolphins were imitating the signals. Dolphin sonograms are graphed on a whistle contour (frequency) axis and a time axis. Different objects, for example rings and balls, had different signals, but eventually the dolphins were able to create novel combinations, for example a ring-ball whistle. To ensure the novelty of a combined signal, signals were considered separate if there was a half-second of quiet time between whistles. The dolphins exhibited self-organized learning, adding signals to their 'vocabulary'. They also made clear associations between sounds and objects, often making the signals for a particular object before hitting the key. This keyboard interface between humans and dolphins prefigured the Interspecies Internet that Dr Reiss and Peter Gabriel are bringing about.
The topic then shifted to the subject of Dr Reiss' book The Dolphin in the Mirror: Exploring Dolphin Minds and Saving Dolphin Lives, specifically Mirror Self Recognition in animals. One index of self awareness is the ability to recognize oneself in a mirror. The 'mirror test' requires selective attention, obtaining potential information, and interpretation of this information, be it conspecific or interspecies information. Mirror Self Recognition requires mental capacity and motivation- one must be motivated to view oneself. Baby humans begin to exhibit Mirror Self Recognition at 12-14 months of age, which is the age at which they begin to demonstrate empathy. Originally, Mirror Self Recognition was thought to be unique to humans, until it was discovered in the great apes- gibbons and monkeys do not exhibit it. The great apes also exhibit some degree of empathy. The basic approach to determining Mirror Self Recognition is to display a mirror and observe what happens. Originally, animals will exhibit exploratory behavior and then social behavior (reacting to the image as a conspecific), then more sophisticated animals will engage in touching and testing the image, which Dr Reiss jokingly termed the 'Groucho test'. Most animals will remain at the level in which they treat the image in the mirror as another individual of the same species. Humans, dolphins, and great apes will engage in contingency testing to determine that they are indeed the individual 'in the mirror', then they engage in self-directed behavior, basically checking themselves out:
In order to determine Mirror Self Recognition, researchers can administer the Mark Test- a part of the subject's body is marked and then the subject is exposed to a mirror and observed to determine if it touches the mark. About 50% of chimpanzees and a sizable number of human children are not interested in the mark. When subject to the Mark Test, dolphins exhibit extremely sophisticated behavior- they engage in no social interaction (my guess would be that their echolocation immediately reads the mirror as 'wall' and not 'buddy') but immediately rush to the mirror to check the mark.
Dolphins and humans are separated by tens of millions of years of evolutionary development but the same cognitive ability with regards to Mirror Self Awareness- this is known as Cognitive Convergence. Certain elephants also exhibit Mirror Self Recognition:
Magpies can also exhibit Mirror Self Recognition.
Dr Reiss then brought her doctoral student Eric Ramos, who is using drones to study dolphin behavior around Turneffe Atoll off the coast of Belize. Dolphins are long-lived animals and must be studied long term. While it's relatively easy to record sounds, it's difficult to observe dolphin behavior. Using drones, one can get a better view of different foraging strategies, and display patterns can be paired with associated sounds.
Dr Reiss then returned to the stage to wrap things up, eloquently arguing that the relationship between science and advocacy must be rethought. When she was beginning her career studying dolphins, the two were generally kept separate, science was supposed to be a 'neutral' endeavor. In her years of studying dolphins, she came to the conclusion that she needed to give voice on behalf of dolphins in order to protect them. She was involved in the production of The Cove, which documented a slaughter of dolphins near the fishing village Taijii, Japan. Dr Reiss stated that science must inform policy, and that knowledge must transcend geographic and cultural boundaries- facts can change policy and spreading facts can lead to change.
While the Bastard was unable to get a question in edgewise during the Q&A, he was able to ask Dr Reiss afterwards about, to use an unforgivably anthropomorphic term, dolphin 'dialects' (I prefaced it with 'distinct vocal suites'). Dr Reiss noted that the initial sound of dolphin contact calls tends to be geographically distinct. He also asked if interspecies communication between different cetacean species (say, bottlenose to spotted dolphin communication or common dolphin to pilot whale communication) had ever been observed, and she indicated that no real inquiry has been done regarding this topic.
Once again, the Secret Science Club presented a dynamite lecture featuring a speaker whose knowledge was matched only by her devotion to her cetacean partners in science. Dr Reiss filled us with information and then challenged us to act on behalf of dolphins, both as species and as individuals. Kudos go to Dr Reiss, Eric Ramos, Dorian and Margaret, and the staff of the beautiful Bell House.
Here is a TED talk featuring Dr Reiss:
Here is another TED talk, specifically dealing with the subject of the good doctor's book:
There are also video accompaniments to Dr Reiss' book. Pour yourself a nice drink and get a tiny taste of that Secret Science ambiance... you won't even have to brave the snowy sidewalks of Brooklyn to do so.
The best studies of dolphin social networks were conducted with Atlantic spotted dolphins (Stenella frontalis) in Bimini and Belize
ReplyDeleteLet us not forget the studies of antisocial networks in orcas.
I was in a doctors office yesterday (dad having some procedure), and read Scientific American. They had a skeptical article about cognitive abilities in animals. (I don't think porpoises were mentioned, though.)
ReplyDeletehttp://www.nature.com/scientificamerican/journal/v314/n1/full/scientificamerican0116-66.html
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Let us not forget the studies of antisocial networks in orcas.
ReplyDeleteI blame those outlandish outfits they wear- it's easy to be dangerous when it's Halloween all the time.
I was in a doctors office yesterday (dad having some procedure), and read Scientific American. They had a skeptical article about cognitive abilities in animals. (I don't think porpoises were mentioned, though.)
Hope dad is well. Thanks for the article.