Category Archives: Animals

other animal brains and behavior compared to human

Free Will has lost all meaning

A headline got me going and the summary got me laughing, “Even worms have free will.” ScienceDaily has the item (here) on a paper about reactions of a worm to odors (A. Gordus, N. Pokala, S. Levy, S. Flavell, C. Bargmann; Feedback from Network States Generates Variability in a Probabilistic Olfactory Circuit; Cell, 2015)

This is not just any worm that has free will, it is C. elegans, a microscopic worm whose brain is completely known, all 302 neurons and their few thousand connecting synapses. Each neuron has a name and has been individually studied. Most of the little networks in the tiny brain have been studied to some extent. What can they mean when they say that C.elegans has free will? “If offered a delicious smell, for example, a roundworm will usually stop its wandering to investigate the source, but sometimes it won’t. Just as with humans, the same stimulus does not always provoke the same response, even from the same individual.

So it appears that free will can be ascribed to anything that is not completely predictable. Until, that is, it is understood enough to be predictable. But no, it does not even have to be unpredictable. They appear to have an understanding of the little 3 neuron web that controls whether the worm stops at an odor. “We found that the collective state of the three neurons at the exact moment an odor arrives determines the likelihood that the worm will move toward the smell.” So it appears that anything that can do more than a single thing when triggered with a particular stimulation, has free will. I think that would include all living things and a good many inanimate things too. Weather seems to fit the bill.

I hate to be pedantic but why use the phrase ‘free will’ with a meaning that is not remotely related to its philosophical meaning or its legal meaning. It either means that a choice is made outside the brain in some spiritual mind or it means that a choice was made consciously and carries attached responsibility. It should not be reduced to a meaning like: a worm will stop for a smell or go on depending on the state of 3 of its neurons. If sensory information is going to have only one effect on motor action, we do not need a brain at all; the sensory neurons can connect directly with the motor neurons with no need for other neurons in between. C. elegans may have a very small brain but it is a brain and it’s function is to nuance behavior – not a surprise when it does.

Here is the abstract, unlike the press release, it is very reasonable and does not mention free will:

Variability is a prominent feature of behavior and is an active element of certain behavioral strategies. To understand how neuronal circuits control variability, we examined the propagation of sensory information in a chemotaxis circuit of C. elegans where discrete sensory inputs can drive a probabilistic behavioral response. Olfactory neurons respond to odor stimuli with rapid and reliable changes in activity, but downstream AIB interneurons respond with a probabilistic delay. The interneuron response to odor depends on the collective activity of multiple neurons—AIB, RIM, and AVA—when the odor stimulus arrives. Certain activity states of the network correlate with reliable responses to odor stimuli. Artificially generating these activity states by modifying neuronal activity increases the reliability of odor responses in interneurons and the reliability of the behavioral response to odor. The integration of sensory information with network states may represent a general mechanism for generating variability in behavior.

 

Another brick gone in the wall

The idea that there is an unbridgeable gap between human language and animal communication has taken another hit. For many years it has been maintained that chimpanzees cannot change their vocal signals, so although the grunts vary in different populations, in any particular group they are fixed. Therefore their vocalizations were not at all like a proto-language. A new paper by Watson and others (citation below) documents change in the vocalization in chimpanzees.

Goodall has said, “the production of sound in the absence of an appropriate emotional state seems to be an almost impossible task for a chimpanzee”. The general consensus was that variation of vocalization depends on emotional not informational factors, and that manual gestures were relatively flexible and intentional, whereas vocal signals were fixed.

The new study shows that chimpanzees can change the grunt for a particular food in order to better communicate with another group that they have joined. They can learn vocal symbols in a social context.

This make a big difference to our understanding of our own language ability. The proposition that our close relatives lack some important ingredient in the make-up of their brains and that is why they did not evolve a proper language has become extremely weak. It cannot be assumed that language is such an obvious advantage that any animal that has not evolved language obviously is unable to. The other idea therefore becomes stronger – we have language because we are more cooperative and trusting than our cousins. Language use is risky. Once individuals can risk open communication within a society, language takes off in both cultural and biological evolution (fast, although it probably took a few hundred thousand years). It is likely that all the ingredients were there (in our common ancestor with chimpanzees) for a proto-language and all that was needed was the safety to talk.

Here is the abstract: “One standout feature of human language is our ability to reference external objects and events with socially learned symbols, or words. Exploring the phylogenetic origins of this capacity is therefore key to a comprehensive understanding of the evolution of language. While non-human primates can produce vocalizations that refer to external objects in the environment, it is generally accepted that their acoustic structure is fixed and a product of arousal states. Indeed, it has been argued that the apparent lack of flexible control over the structure of referential vocalizations represents a key discontinuity with language. Here, we demonstrate vocal learning in the acoustic structure of referential food grunts in captive chimpanzees. We found that, following the integration of two groups of adult chimpanzees, the acoustic structure of referential food grunts produced for a specific food converged over 3 years. Acoustic convergence arose independently of preference for the food, and social network analyses indicated this only occurred after strong affiliative relationships were established between the original subgroups. We argue that these data represent the first evidence of non-human animals actively modifying and socially learning the structure of a meaningful referential vocalization from conspecifics. Our findings indicate that primate referential call structure is not simply determined by arousal and that the socially learned nature of referential words in humans likely has ancient evolutionary origins.
ResearchBlogging.org

Watson, S., Townsend, S., Schel, A., Wilke, C., Wallace, E., Cheng, L., West, V., & Slocombe, K. (2015). Vocal Learning in the Functionally Referential Food Grunts of Chimpanzees Current Biology DOI: 10.1016/j.cub.2014.12.032

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Wolf to dog

Why were dogs domesticated so early? How was it done? A recent paper (citation below) looks at how much of dog behaviour might have been already in the wolf with no effort needed to produce it in the dog. All that may have been needed was to have the wolf lose its fear of man and accept man as a partner.

The researchers, Range and Viranyi, looked at the levels of tolerance and attentiveness in wolves and dogs that were living in the same sort of group and enclosure with the same interaction with humans during their whole lives. In other words they compared like with like rather than pets with wild animals. They were looking at cooperation which has its foundation in two traits. Social tolerance, the ease with which animals live and ‘work’ together, is “usually measured in the context of feeding, which is not accompanied with aggression or, if aggression occurs, it is bidirectional and ritualized.” Tolerance points to particular social emotions and communication. Social attentiveness, the amount of monitoring of companions, is important in cooperation, to know a partner’s behavior and intentions by close observation. Following another’s gaze is an indication of attentiveness. They put forward a hypothesis: “Based on findings that in intraspecific contexts wolves are at least as socially attentive and tolerant as dogs, the Canine Cooperation Hypothesis postulates that dog-human cooperation evolved on the basis of wolf-wolf cooperation. In contrast to many domestication hypotheses, it suggests that dogs did not need to be selected for a general increase in their social attentiveness and tolerance. ”

There was one experiment in particular that I found very interesting. “… we investigated gaze following into distant space and around barriers in wolves. This ability to coordinate with others’ head orientation to look in the same direction is considered a key step toward an understanding of others mental states like attention and intention and thus, is potentially also very important for being able to successfully cooperate. However, while gaze following into distant space could be simply a socially facilitated orientation response (i.e., a predisposition to look where others are looking) , gaze following around barriers, where individuals need to reposition themselves to look behind the obstacle and assess the visual persepctive of the cue-giver different from their own, has been suggested to require a mental representation of the looker’s visual perspective or learning how visual barriers impair perceptions. Accordingly, this latter ability to track another’s gaze around obstacles seems to be cognitively more advanced, and has been suggested to occur especially in species with high levels of cooperative and competitive interactions. Our results showed that wolves followed human gaze as readily as conspecific gaze implying their high social attention and their readiness to accept humans as social partners who might provide important information. ” I have thought that some dogs such as seeing-eye dogs had the ability to envisage the size, shape and mobility of their charges as if they could imagine ‘walking in their shoes”. This sort of ‘dog owners’ belief has been criticized heavily but has not changed the opinion of many owners. It is nice to see some experimental evidence of that type of ability in canines.

Here is the abstract : “At present, beyond the fact that dogs can be easier socialized with humans than wolves, we know little about the motivational and cognitive effects of domestication. Despite this, it has been suggested that during domestication dogs have become socially more tolerant and attentive than wolves. These two characteristics are crucial for cooperation, and it has been argued that these changes allowed dogs to successfully live and work with humans. However, these domestication hypotheses have been put forward mainly based on dog-wolf differences reported in regard to their interactions with humans. Thus, it is possible that these differences reflect only an improved capability of dogs to accept humans as social partners instead of an increase of their general tolerance, attentiveness and cooperativeness. At the Wolf Science Center, in order to detangle these two explanations, we raise and keep dogs and wolves similarly socializing them with conspecifics and humans and then test them in interactions not just with humans but also conspecifics. When investigating attentiveness toward human and conspecific partners using different paradigms, we found that the wolves were at least as attentive as the dogs to their social partners and their actions. Based on these findings and the social ecology of wolves, we propose the Canine Cooperation Hypothesis suggesting that wolves are characterized with high social attentiveness and tolerance and are highly cooperative. This is in contrast with the implications of most domestication hypotheses about wolves. We argue, however, that these characteristics of wolves likely provided a good basis for the evolution of dog-human cooperation.
ResearchBlogging.org

Range, F., & Virányi, Z. (2015). Tracking the evolutionary origins of dog-human cooperation: the “Canine Cooperation Hypothesis” Frontiers in Psychology, 5 DOI: 10.3389/fpsyg.2014.01582

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The roots of language

If you are not searching for something, then you are unlikely see it. That has been so with language. There was an agreement on what language was and how it came to be. Any other way of looking at things was hardly considered. But now language is seen in a different light – part of the spectrum of animal communication. Recently there have been some very interesting papers – on dogs, birds, monkeys and cows.

Dogs: They understand our language very much as we do. They process separately the words or the phonemic sound from the non-word aspects or the prosodic cues. We do this. We separate the verbal information from the emotional sound envelop. And the dogs like us do the word-meaning work in the left hemisphere and the tone of voice work in the right hemisphere, in similar regions. This implies that the lateralization of aspects of communication is probably an old feature of the mammalian brain. The two abstracts below explain the experimental evidence.

Abstract: (Victoria Ratcliffe, David Reby; Orienting Asymmetries in Dogs’ Responses to Different Communicatory Components of Human Speech; Cell Current Biology Volume 24, Issue 24, p2908–2912, 15 December 2014) “It is well established that in human speech perception the left hemisphere (LH) of the brain is specialized for processing intelligible phonemic (segmental) content, whereas the right hemisphere (RH) is more sensitive to prosodic (suprasegmental) cues. Despite evidence that a range of mammal species show LH specialization when processing conspecific vocalizations, the presence of hemispheric biases in domesticated animals’ responses to the communicative components of human speech has never been investigated. Human speech is familiar and relevant to domestic dogs (Canis familiaris), who are known to perceive both segmental phonemic cues and suprasegmental speaker-related and emotional prosodic cues. Using the head-orienting paradigm, we presented dogs with manipulated speech and tones differing in segmental or suprasegmental content and recorded their orienting responses. We found that dogs showed a significant LH bias when presented with a familiar spoken command in which the salience of meaningful phonemic (segmental) cues was artificially increased but a significant RH bias in response to commands in which the salience of intonational or speaker-related (suprasegmental) vocal cues was increased. Our results provide insights into mechanisms of interspecific vocal perception in a domesticated mammal and suggest that dogs may share ancestral or convergent hemispheric specializations for processing the different functional communicative components of speech with human listeners.

Abstract: (Attila Andics, Márta Gácsi, Tamás Faragó, Ádám Miklósi; Voice-Sensitive Regions in the Dog and Human Brain Are Revealed by Comparative fMRI; Cell Current Biology Volume 24, Issue 5, p574–578, 3 March 2014) “During the approximately 18–32 thousand years of domestication, dogs and humans have shared a similar social environment. Dog and human vocalizations are thus familiar and relevant to both species, although they belong to evolutionarily distant taxa, as their lineages split approximately 90–100 million years ago. In this first comparative neuroimaging study of a nonprimate and a primate species, we made use of this special combination of shared environment and evolutionary distance. We presented dogs and humans with the same set of vocal and nonvocal stimuli to search for functionally analogous voice-sensitive cortical regions. We demonstrate that voice areas exist in dogs and that they show a similar pattern to anterior temporal voice areas in humans. Our findings also reveal that sensitivity to vocal emotional valence cues engages similarly located nonprimary auditory regions in dogs and humans. Although parallel evolution cannot be excluded, our findings suggest that voice areas may have a more ancient evolutionary origin than previously known.”

It has also been shown that some dogs (border collies) can learn a remarkable number of words, many hundred names for toy objects, some verbs and adjectives. This implies that the structures in our language are not unique. Objects, proper names, actions, attributes are all aspects of our perception of the world and seem to be basic to the mammalian brain’s way of thinking. The idea of an agent causing a change is how a working border collie earns its keep. Nothing new here – these are old architectural feature of the brain that language appears to have harnessed.

Birds: Recently 100+ researchers with use of 9 supercomputers analyzed the genomes of 48 species of birds. The results have just been published in 28 papers appearing together in various journals. There is now a complete outline of the bird family tree. There is a similarity between our genes and those of birds groups that have vocal abilities. Behaviorally there are similarities in the learning of vocalizations. Besides ourselves and the songbirds, vocal learners include dolphins, sea lions, bats and elephants; and in birds, parrots and hummingbirds as well as the songbirds. The genetic similarity is found in 55 genes shared by us and songbirds, a pattern found only in vocal-learners.

Scientific American reviewed this research (here) “The similarity of the gene networks needed for vocal learning between humans and birds is not completely surprising. After all, all vocal-learning species can trace their ancestry back to the same basal branches on the tree of life, White says. Even though the ability evolved independently, it was influenced by a similar initial deal from the genetic deck of cards. Also, the broadly similar environment of this Earth created the evolutionary pressures that shape vocal learners. Just as multiple species came up with similar solutions to the problem of vision, species that evolved vocal learning seem to have settled on common strategies. Viewed from another angle, however, the convergence is striking. “This, to my knowledge, is the first time a learned behavior has been shown to have so much similar molecular underpinnings,” White says. The discoveries open up a host of potential avenues for future exploration: Can nonvocal learners acquire some traits needed for vocal learning simply by tweaking some key genes? Almost certainly, zebra finches have more to tell us about our own ability to babble, shout and sing. ”

Monkeys: We have been told that monkey’s use of calls is nothing like language, because they are fixed, neither learned or elaborated. But a new study examines the differences between the use of the calls in the same species but in difference places. The differences can be explained by established human language mechanisms. When two words compete and one (A) has a more specific meaning and the other (B) has a general meaning – then (B)’s meaning will change so that it doesn’t include (A) but only all other instances of the general meaning. There is a rudimentary ‘primate linguistics’ that is not non-language like. Here is the abstract.

Abstract: (Philippe Schlenker, Emmanuel Chemla, Kate Arnold, Alban Lemasson, Karim Ouattara, Sumir Keenan, Claudia Stephan, Robin Ryder, Klaus Zuberbühler; Monkey semantics: two ‘dialects’ of Campbell’s monkey alarm calls; Linguistics and Philosophy, 2014; 37 (6)) “We develop a formal semantic analysis of the alarm calls used by Campbell’s monkeys in the Tai forest (Ivory Coast) and on Tiwai island (Sierra Leone)—two sites that differ in the main predators that the monkeys are exposed to (eagles on Tiwai vs. eagles and leopards in Tai). Building on data discussed in Ouattara et al. (PLoS ONE 4(11):e7808, 2009a; PNAS 106(51): 22026–22031, 2009b and Arnold et al. (Population differences in wild Campbell’s monkeys alarm call use, 2013), we argue that on both sites alarm calls include the roots krak and hok, which can optionally be affixed with -oo, a kind of attenuating suffix; in addition, sentences can start with boom boom, which indicates that the context is not one of predation. In line with Arnold et al., we show that the meaning of the roots is not quite the same in Tai and on Tiwai: krak often functions as a leopard alarm call in Tai, but as a general alarm call on Tiwai. We develop models based on a compositional semantics in which concatenation is interpreted as conjunction, roots have lexical meanings, –oo is an attenuating suffix, and an all-purpose alarm parameter is raised with each individual call. The first model accounts for the difference between Tai and Tiwai by way of different lexical entries for krak. The second model gives the same underspecified entry to krak in both locations (= general alarm call), but it makes use of a competition mechanism akin to scalar implicatures. In Tai, strengthening yields a meaning equivalent to non-aerial dangerous predator and turns out to single out leopards. On Tiwai, strengthening yields a nearly contradictory meaning due to the absence of ground predators, and only the unstrengthened meaning is used.”

Cows: ScienceDaily reported (here) on a press release, “Do you speak cow?” on research led by Monica Padilla de la Torre from University of Queen Mary London. “They identified two distinct maternal ‘calls’. When cows were close to their calves, they communicated with them using low frequency calls. When they were separated — out of visual contact — their calls were louder and at a much higher frequency. Calves called out to their mothers when they wanted to start suckling. And all three types of calls were individualized — it was possible to identify each cow and calf using its calls.”

Many animals have been shown to recognize other individuals and to identify themselves vocally. But it is still a surprise that an animal like a cow has ‘names’. It could be a general ability among mammals.

Work like this on other animals is likely to further illustrate the roots of our language. It takes looking rather than accepting the idea that our language has no roots to be found in other animals.

 

Crows

I think it is time to look at crows again. There are three interesting papers want to commented on. What reminds me of crows is that I stumbled across a few years old blog by a linguist (he has probably changed his tune – so no references) who ridiculed the idea that birds were at all smart because they had tiny brains with no ‘higher’ brain anatomy. He was unwilling to take seriously any of the work of Pepperberg with her parrot Alex. How the climate has changed in a few years.

The most recent paper is review in ScienceDaily (here) : Martinho, Burns, von Bayern, Kacelnik. “Monocular Tool Control, Eye Dominance, and Laterality in New Caledonian Crows.” Current Biology, 2014. It deals with the seeming ‘handedness’ in the way crows hold tools. It is actually ‘eyedness’; the crows hold the tool on one side of the beak, so that they see the end of the tool and the target with their preferred eye. Caledonia crows have have unusually forward looking eyes and a substantial area of binocular vision. The researchers found that the crows use a monocular part of the opposite side eye to see clearly when using a tool. This implies that they are anatomically adapted to tool use. “In other words, the birds are using their notable binocular vision for better monocular vision, allowing each eye to see further toward the other side of the beak. The birds’ unusually wide binocular field is among the first known examples of a physical adaptation to enable tool use, the researchers say.

In another paper from the spring (citation below), Jelbert and others investigate the extant of New Caledonian crow’s understanding of how to displace water to receive a reward and found that they had the causal understanding level of a 5-7 year-old child. Wild crows, after short training, were tested in 6 Aesop fable type tasks. They could solve 4 of them: dropping stones into water but not sand filled tubes, dropping sinking not floating and solid not hollow objects, and dropping into tubes with higher water levels. They failed to solve 2 of them: understanding tubes of difference diameter and U shaped tubes. The results show the understanding the causal idea of volume displacement at about the level of the 5-7 year old child. “These results are striking as they highlight both the strengths and limits of the crows’ understanding. In particular, the crows all failed a task which violated normal causal rules, but they could pass the other tasks, which suggests they were using some level of causal understanding when they were successful.

Last year there was a paper reviewed by ScienceDaily (here): Veit, Nieder. “Abstract rule neurons in the endbrain support intelligent behaviour in corvid songbirds.” Nature Communications, 2013; 4. This paper dealt with how crows make strategic decisions. As crows do many things that are thought of as primate strengths and yet have a very different brain architecture, this is a way to look at intelligence in a fundamental way that would apply to both primates and crows.

Crows were trained to do a memory test. On a computer screen they were shown an image, they had to remember the image and later pick one of two images on the screen. The hard part was that sometimes they had to pick the image that was the same and other times the one that was different. They had to switch back and forth between two rules-of-the -game. They could use this mental flexibility, which even takes effort for humans. While the birds were engaged in this task their nidopallium caudolaterale area of the brain was monitored. One group of cells was active for the different image rule and another for the same image rule.

Crows and primates have different brains, but the cells regulating decision-making are very similar. They represent a general principle which has re-emerged throughout the history of evolution. “Just as we can draw valid conclusions on aerodynamics from a comparison of the very differently constructed wings of birds and bats, here we are able to draw conclusions about how the brain works by investigating the functional similarities and differences of the relevant brain areas in avian and mammalian brains.

Citation: Sarah A. Jelbert, Alex H. Taylor, Lucy G. Cheke, Nicola S. Clayton, Russell D. Gray. Using the Aesop’s Fable Paradigm to Investigate Causal Understanding of Water Displacement by New Caledonian Crows. PLoS ONE, 2014; 9 (3): e92895 DOI: 10.1371/journal.pone.0092895
ResearchBlogging.org

Veit, L., & Nieder, A. (2013). Abstract rule neurons in the endbrain support intelligent behaviour in corvid songbirds Nature Communications, 4 DOI: 10.1038/ncomms3878

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Habits and learning

Habits allow us to perform actions without attending to every detail; we can do complex things and more than one action at a time without overloading our cognitive and motor systems. They are goal-directed macro actions made up of a sequence of simple primitive actions. A habit allows a complex action to be launched as a unit and efficiently reach the goal of the habit without each step needing its own specific goal.

In forming a habit, a sequence of actions is consolidated by passing from a closed reward loop to an open reward loop. In other words the whole sequence comes to be evaluated rather than each step. Passing from step to step becomes much faster when it is automatic. “To explain how these sequences are consolidated, Dezfouli and Balleine distinguish between closed-loop and open- loop execution. At the beginning of learning, feedback is crucial. The organism needs a reward or some clues in the environment to identify and perform the proper behavior (closed-loop execution). In advanced stages of training, a step in the sequence is conditioned by the previous step, regardless of feedback stimuli or reward (open-loop execution). This independence accounts for the insensitivity to the outcome shown in experiments of reward devaluation and contingency degradation that are standard measures to determine if a habit has been acquired .” It takes persistent failure of the expected reward to disrupt the habit.

Learning is adaptation of an individual to the environment by changes in behavior resulting from regularities in the environment. Learning is adaptive because it is a response to regularity. As habits present regularities in the environment because one step automatically follows another, they can be the basis of learning.

The author, Balderas, (see citation below) uses the fast-mapping that dogs do in learning to associate a name with an object, to illustrate the intertwining of habit and learning. Only some dogs do fast-mapping: learning that a new word applies to the only new object available using exclusion logic. Other dogs stand about looking lost. She explains the learning of a particular dog, Rico, that uses two habits (automatic sequences): one is playing fetch and the other is associating a name with an object. The fetch sequence has three main actions (a) go for (b) select (c) deliver. Select however can be seen as a sub-sequence (1) look-for (2) match (3) take. If there is no new object/name then abc can be executed without interruption. But during fast-mapping it becomes more complex. “In this case, take can not start because match was not executed. Since Rico does not dispose of a name-object association that enables it to complete the task, it is in a situation where it has to make a decision in the middle of the selection task, so the goal-directed system regains control. After solving the problem, the fetching-game sequence follows its tendency to completion and Rico returns to the sequence: it goes to take and to c (deliver). This description also follows the hierarchical view because at the starting point the behavior begins as a habit, when a decision is required it becomes goal-directed and ends again as a habit after overcoming the difficulty.” The dog uses the exclusion principle, and that involves the matching of previously learned pairs to eliminate them. When the dog finds the only possible answer is the unmatched object, he must select this object in order to deliver and reach the end-point, the habit’s goal. This sequence results in learning a new name/object matching. Habits modulate behavior and guide the animal to detect and solve a problem and thus learn.

I have to admit that part of the reason for this post is my love of a former dog (a much missed border collie – husky cross) who could learn vocabulary, including by the exclusion principle. We were building a house and the internal walls were only the studs. I had shown people around and the dog had followed. I would stand in a space and say this is the kitchen and then go on to the next room. After a few times the dog preceded the group. Then I would stay in the middle of the house and say, “Badger, show them the kitchen”. She did the tour with me only naming the rooms. Then one day I said, “show them the basement”. The dog looked at me and around the space, a couple of times and then trotted to the top of the stairs to the basement. I don’t think she picked up the word ‘basement’ from conversations or she would not have been puzzled at first, but she did recognize that it was the only space left that she could possibly show them. From then on she could be told to go to the basement and she understood. When the walls were finished she could still be told to go to a particular room, although now she had to use the doors.
ResearchBlogging.org

Balderas, G. (2014). Habits as learning enhancers Frontiers in Human Neuroscience, 8 DOI: 10.3389/fnhum.2014.00918

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Down with untrue intros

 

There are often opening sentences like, “only humans can x” or “only primates can x”. Why do people assume these sorts of statements are true without checking? Why does no one seem to complain? Either authors and readers don’t really care if the statements are true – they are just openers and not the important part of the piece; or they want the statements to be true and so are shy about looking at any evidence.

A recent paper (Anna Kis, Ludwig Huber, Anna Wilkinson. Social learning by imitation in a reptile (Pogona vitticeps). Animal Cognition, 2014) was reported in ScienceDaily with the opening line, “The ability to acquire new skills through the ‘true imitation’ of others’ behaviour is thought to be unique to humans and advanced primates, such as chimpanzees.” I knew this was not true and that other animals have this skill (a number of mammals besides primates and a number of birds). Looking at the abstract of the paper, I found a similar opening line. It was not so restrictive – “The ability to learn through imitation is thought to be the basis of cultural transmission and was long considered a distinctive characteristic of humans. There is now evidence that both mammals and birds are capable of imitation.” But even this is a bit restricted as octopuses also learn from one another. We should not be sure that some animal (an social insect for example) does not do x unless we have looked to see. And throw-away openings should be at least true.

But the paper has interesting news. Bearded dragons can learn from one another! Reptiles can be included too. We are more closely related to these reptiles than to birds. This finding strengthens the idea that social learning is an ancient skill in vertebrates, rather than separately evolved in various types of vertebrates. Although it is still reasonable to think that it evolved separately in invertebrates.

Here is the abstract:

The ability to learn through imitation is thought to be the basis of cultural transmission and was long considered a distinctive characteristic of humans. There is now evidence that both mammals and birds are capable of imitation. However, nothing is known about these abilities in the third amniotic class—reptiles. Here, we use a bidirectional control procedure to show that a reptile species, the bearded dragon (Pogona vitticeps), is capable of social learning that cannot be explained by simple mechanisms such as local enhancement or goal emulation. Subjects in the experimental group opened a trap door to the side that had been demonstrated, while subjects in the ghost control group, who observed the door move without the intervention of a conspecific, were unsuccessful. This, together with differences in behaviour between experimental and control groups, provides compelling evidence that reptiles possess cognitive abilities that are comparable to those observed in mammals and birds and suggests that learning by imitation is likely to be based on ancient mechanisms.

Underestimating dolphin’s brains

I have been reading in the social media an essay by Captain Paul Watson, and as I know nothing about his scientific credentials, I have been fact checking. Watson was associated over the years with a number of conservation groups, especially Sea Shepherd Conservation Society.

From other sites I find that his description of the dolphin brain is a good one. The cetacean brain has been large for a long time compared to humans and it is indeed very large. It is unusual in having four rather than three cerebral lobes. Its cerebrum is differently organized with an unusually large association cortex and a very close ‘cortical adjacency’ of the senses and motor areas.

The human brain, like most mammals, has a cerebrum divided into a rhinic lobe, limbic lobe and supralimbic lobe (divided into sub-lobes occipital, parietal, temporal, frontal). In the dolphin there are four lobes. The rhinic is somewhat different. The limbic lobe is large but similar to ours. Between the limbic and the supralimbic another lobe is inserted, the paralimbic. The supralimbic is not divided into sub-lobes and appears to be totally associative, like our frontal lobe. The sensory and motor areas occur in the paralimbic lobe, but they are organized differently: much more integrated and in close contact. Some believe that this gives a more unified perception without separate senses but with a single sort of perception. The cetaceans use an acoustic (sonar) sense that seems to be at one with their vision. The contact between sensory and motor areas may give the animals great speed of perception and action.

Watson’s essay (here) points out: Interspecies (intelligence) comparisons focus on the extent of lamination, the total cortical area, and the number and depth of neocortex convolutions. In addition, primary sensory processing relative to problem solving is a significant indicator; this can be described as associative ability. The association or connecting of ideas is a measurable skill: a rat’s associative skill is measured at nine to one. This means that 90 percent of the brain is devoted to primary sensory projection, leaving only 10 percent for associative skills. A cat is one to one, meaning that half the brain is available for associative ability. A chimpanzee is one to three, and a human being is one to nine. We humans need only utilize 10 percent of our brains to operate our sensory organs. Thus the associative abilities of a cat are measurably greater than a rat but less than a chimp, and humans are the highest of all. Not exactly. The cetacean brain averages one to twenty-five and can range upward to one to forty. The reason for this is that the much larger supralimbic lobe is primarily association cortex. (and not basic sensory and motor cortex)

In humans, the projection areas for different senses are widely separated from one another, and the motor area is adjacent to the touch area. For us to make an integrated perception from sight, sound, and touch, impulses must travel by long fiber tracts with a great loss of time and information. The cetacean’s paralimbic system makes possible the very rapid formation of integrated perceptions with a richness of information unimaginable to us. He gives an example: A dolphin can see a tumor inside the body of another dolphin. If an animal is drowning, this becomes instantly recognizable from being able to “see” the water filling the lungs.

…Based upon comparisons of cortical structure alone, a sperm whale would score 2,000 (in IQ). The truth of the matter is that we know absolutely nothing about what goes on in the brain of a whale or a dolphin. In our ignorance, we resort to the arrogance of denial and dismissal. We deny the physiological evidence and in general we have denied that other animals can think or even feel.

Sight in humans is a space-oriented distance sense which gives us complex simultaneous information in the form of analog pictures with poor time discrimination. By contrast, our auditory sense has poor space perception but good time discrimination. This results in human languages being comprised of fairly simple sounds arranged in elaborate temporal sequences. The cetacean auditory system is primarily spatial, more like human eyesight, with great diversity of simultaneous information and poor time discrimination. For this reason, dolphin language consists of very complex sounds perceived as a unit. What humans may need hundreds of sounds strung together to communicate, the dolphin may do in one sound. To understand us, they would have to slow down their perception of sounds to an incredibly boring degree. It is for this reason that dolphins respond readily to music. Human music is more in tune with dolphin speech.

While I was looking at Watson and some authorities on cetacean anatomy, there was a blog on Babel’s Dawn about dolphin names. (here) The message was that using names does not in itself make a language; language talks about some topic. It seems to me that looking for something that we would call a language in whales and dolphins is probably not a reasonable search. What we really want to know is how cetaceans communicate. We know that they have sophisticated ways of communicating from their behavior. We have no idea whether their communication is analogous to our language, with matching points of reference or structural relationships or whether it has a completely different sort of structure. We have no idea whether their communication is in any way superior or inferior to ours. We also have little idea of their knowledge and culture; they could be all the way from impoverished to rich.

Chimps appreciate rhythm

 

Science Daily has an item (here) on musical appreciation in chimpanzees. Previous studies using blues, classical and pop music have found that although chimps can distinguish features of music and have preferences, they still preferred silence to the music. So were the chimps able to ‘hear’ the music but not appreciate its beauty? A new paper has different results using non-western music: West African akan, North Indian raga, and Japanese taiko. Here the chimps liked the African and Indian music but not the Japanese. They seemed to base their appreciation on the rhythm. The Japanese music has very regular prominent beats like western music, while the African and Indian music had varied beats. “The African and Indian music in the experiment had extreme ratios of strong to weak beats, whereas the Japanese music had regular strong beats, which is also typical of Western music.”

It may be that they like a more sophisticated rhythm. Or de Waal says, ““Chimpanzees may perceive the strong, predictable rhythmic patterns as threatening, as chimpanzee dominance displays commonly incorporate repeated rhythmic sounds such as stomping, clapping and banging objects.”

Here is the abstract for M. Mingle, T. Eppley, M. Campbell, K. Hall, V. Horner, F. de Waal; Chimpanzees Prefer African and Indian Music Over Silence;Journal of Experimental Psychology: Animal Learning and Cognition, 2014:

All primates have an ability to distinguish between temporal and melodic features of music, but unlike humans, in previous studies, nonhuman primates have not demonstrated a preference for music. However, previous research has not tested the wide range of acoustic parameters present in many different types of world music. The purpose of the present study is to determine the spontaneous preference of common chimpanzees (Pan troglodytes) for 3 acoustically contrasting types of world music: West African akan, North Indian raga, and Japanese taiko. Sixteen chimpanzees housed in 2 groups were exposed to 40 min of music from a speaker placed 1.5 m outside the fence of their outdoor enclosure; the proximity of each subject to the acoustic stimulus was recorded every 2 min. When compared with controls, subjects spent significantly more time in areas where the acoustic stimulus was loudest in African and Indian music conditions. This preference for African and Indian music could indicate homologies in acoustic preferences between nonhuman and human primates.”

 

Animal – human bias

 

There is a paper (F. Gaunet, How do guide dogs of blind owners and pet dogs of sighted owners (Canis familiaris) ask their owners for food?, Animal Cognition 2008) mentioned in a blog (here) that is billed as showing that guide dogs do not know their owners are blind. Here is the abstract:

Although there are some indications that dogs (Canis familiaris) use the eyes of humans as a cue during human-dog interactions, the exact conditions under which this holds true are unclear. Analysing whether the interactive modalities of guide dogs and pet dogs differ when they interact with their blind, and sighted owners, respectively, is one way to tackle this problem; more specifically, it allows examining the effect of the visual status of the owner. The interactive behaviours of dogs were recorded when the dogs were prevented from accessing food that they had previously learned to access. A novel audible behaviour was observed: dogs licked their mouths sonorously. Data analyses showed that the guide dogs performed this behaviour longer and more frequently than the pet dogs; seven of the nine guide dogs and two of the nine pet dogs displayed this behaviour. However, gazing at the container where the food was and gazing at the owner (with or without sonorous mouth licking), gaze alternation between the container and the owner, vocalisation and contact with the owner did not differ between groups. Together, the results suggest that there is no overall distinction between guide and pet dogs in exploratory, learning and motivational behaviours and in their understanding of their owner’s attentional state, i.e. guide dogs do not understand that their owner cannot see (them). However, results show that guide dogs are subject to incidental learning and suggest that they supplemented their way to trigger their owners’ attention with a new distal cue.

It may or may not be true that these dogs do not know that their owners are blind. This experiment indicates that but not too strongly. I could do an experiment with people talking on telephones and show that a good many of them believe that the person on the other end of the phone can see them because they would use hand gestures while talking. Or I could show that my dog has knowledge of the difference between my eyesight and my husband’s. This is because she does not move out of the way if we step over her in the daytime. She moves at night so as not to be stepped on. But if there is a lot of moonlight she moves for my husband who has poor sight in low light but not for me. She could have learned this by trial and error or she could have reasoned it out as a difference in eyesight. We don’t know. But we do know that the person on the telephone that gestures is not ignorant of what the other person can see. That person is using a habitual routine without even being aware of how silly it is.

The problem is that we treat other people differently from other animals when we try and understand their thinking. We assume animal are unintelligent as a first assumption and have to prove any instance of smarts. On the other hand we insist that humans think things out consciously and have to establish any instance of behavior being not under conscious control. We really should be using similar criteria for all animals ourselves included.