Thursday, June 19, 2008
Six 'uniquely' human traits now found in animals
* 17:11 22 May 2008
* NewScientist.com news service
* Kate Douglas
To accompany the article So you think humans are unique? we have selected six articles from the New Scientist archive that tell a similar story. We have also asked the researchers involved to update us on their latest findings. Plus, we have rounded up six videos of animals displaying 'human' abilities.
Art, theatre, literature, music, religion, architecture and cuisine – these are the things we generally associate with culture. Clearly no other animal has anything approaching this level of cultural sophistication. But culture at its core is simply the sum of a particular group's characteristic ways of living, learned from one another and passed down the generations, and other primate species undoubtedly have practices that are unique to groups, such as a certain way of greeting each other or obtaining food.
Even more convincing examples of animal cultures are found in cetaceans. Killer whales, for example, fall into two distinct groups, residents and transients. Although both live in the same waters and interbreed, they have very different social structures and lifestyles, distinct ways of communicating, different tastes in food and characteristic hunting techniques – all of which parents teach to offspring.
Read the original article: Culture shock (24 March 2001)
Hal Whitehead, Dalhousie University writes:
"Since our 2001 review, people have often considered culture as a potential explanation of the behavioural patterns that have turned up in their studies of whales and dolphins.
"Our own work has concentrated on the non-vocal forms of sperm-whale culture. The different cultural clans of sperm whales, although in basically the same areas, use these waters very differently, and are affected very differently by El Niño events. They also have different reproductive rates.
"In sperm whales, and likely other whales and dolphins, culture has the potential to affect population biology, and so issues as diverse as genetic evolution and the impacts of global warming on the species."
2. Mind reading
Perhaps the surest sign that an individual has insight into the mind of another is the ability to deceive. To outwit someone you must understand their desires, intentions and motives – exactly the same ability that underpins the "theory of mind". This ability to attribute mental states to others was once thought unique to humans, emerging suddenly around the fifth year of life. But the discovery that babies are capable of deception led experts to conclude that "mind-reading" skills develop gradually, and fueled debate about whether they might be present in other primates.
Experiments in the 1990s indicated that great apes and some monkeys do understand deception, but that their understanding of the minds of others is probably implicit rather than explicit as it is in adult humans.
Read the original article: Liar! Liar! (14 February 1998)
Marc Hauser, Harvard University, writes:
"The tamarin work didn't pan out, but there are now several studies that show evidence of theory of mind in primates, including work by Brian Hare, Josep Call, Mike Tomasello, Felix Warneken, Laurie Santos, Justin Wood, and myself on chimps, rhesus monkeys and tamarins. There is nothing quite like a successful Sally-Anne test, but studies point to abilities such as seeing as a form of knowing, reading intentions and goals."
3. Tool use
Some chimps use rocks to crack nuts, others fish for termites with blades of grass and a gorilla has been seen gauging the depth of water with the equivalent of a dipstick, but no animal wields tools with quite the alacrity of the New Caledonian crow. To extract tasty insects from crevices, they craft a selection of hooks and long, barbed tapers called stepped-cut tools, made by intricately cutting a pandanus leaf with their beaks. What's more, experiments in the lab suggest that they understand the function of tools and deploy creativity and planning to construct them.
Nobody is suggesting that toolmaking has common origins in humans and crows, but there is a remarkable similarity in the ways in which their respective brains work. Both are highly lateralised, revealed in the observation that most crows are right-beaked – cutting pandanus leaves using the right side of their beaks. New Caledonian crows may force us to reassess the mental abilities of our first toolmaking ancestors.
Read the original article: Look, no hands (17 August 2002)
Gavin Hunt at the University of Aukland, writes:
"The general aim of our research on New Caledonian crows is to determine how a 'bird brain' can produce such complex tools and tool behaviour. Since the New Scientist article appeared in 2002, our team has focused on continuing to document tool manufacture and use in the wild (New Zealand Journal of Zoology, vol 35 p 115), the development of tool skills in free-living juveniles, the social behaviour and ecology of NC crows on the island of Maré, experimental work investigating NC crows' physical cognition and general intelligence, and neurological work.
"Some of this work is being undertaken collaboratively with laboratories in Germany (neurology) and New Zealand (genotyping). A very similar study is also being carried out independently at the University of Oxford. This parallel research has produced findings that are both confirmatory and conflicting."
Alex Kacelnik, University of Oxford, adds:
"We now know for sure that genetics is involved in the tool-making abilities of new Caledonian crows. We raised nestlings by hand and found that chicks that had never seen anybody handle objects of any kind started to use tools to extract food from crevices at a similar age to those who were exposed to human tutors using tools (Animal Behaviour, vol 72, p 1329). Clearly, observing others is not necessary for the tool use. However chicks exposed to tutoring exhibit a greater intensity of tool-related activity. Not surprisingly, genes and experience show a complex interaction.
"We have also developed a new technique, consisting of loading tiny video cameras on free-ranging birds, so as to see what they see and document the precise use of tools in nature. We have discovered that they use tools in loose soil, that they use a kind of tool not previously described (grass stems), and that they hunt for vertebrates (lizards). All of this, together with laboratory analysis of their cognitive abilities is forming a richer picture of what the species can do."
A classic study in 1964 found that hungry rhesus monkeys would not take food they had been offered if doing so meant that another monkey received an electric shock. The same is true of rats. Does this indicate nascent morality? For decades, we have preferred to find alternative explanations, but recently ethologist Marc Bekoff from the University of Colorado at Boulder has championed the view that humans are not the only moral species. He argues that morality is common in social mammals, and that during play they learn the rights and wrongs of social interaction, the "moral norms that can then be extended to other situations such as sharing food, defending resources, grooming and giving care".
Read the original article: Virtuous nature (13 July 2002)
Marc Bekoff, University of Colorado, writes:
"Work published this year showed that animals are able to make social evaluations and these assessments are foundational for moral behaviour in animals other than humans. Francys Subiaul of the George Washington University and his colleagues showed that captive chimpanzees are able to make judgments about the reputation of unfamiliar humans by observing their behaviour - whether they were generous or stingy in giving food to other humans. The ability to make character judgments is just what we would expect to find in a species in which fairness and cooperation are important in interactions among group members (Animal Cognition, DOI: 10.1007/s10071-008-0151-6)."
Emotions allow us to bond with others, regulate our social interactions and make it possible to behave flexibly in different situations. We are not the only animals that need to do these things, so why should we be the only ones with emotions? There are many examples of apparent emotional behavior in other animals.
Elephants caring for a crippled herd member seem to show empathy. A funeral ritual performed by magpies suggests grief. Was it spite that led a male baboon called Nick to take revenge on a rival by urinating on her? Divers who freed a humpback whale caught in a crab line describe its reaction as one of gratitude. Then there's the excited dance chimps perform when faced with a waterfall – it looks distinctly awe-inspired. These days, few doubt that animals have emotions, but whether they feel these consciously, as we do, is open to debate.
Read the original article: Do animals have emotions? (23 May 2007)
It's no surprise that animals that live under constant threat from predators are extra-cautious, while those that face fewer risks appear to be more reckless. After all, such successful survival strategies would evolve by natural selection. But the discovery that individuals of the same species, living under the same conditions, vary in their degree of boldness or caution is more remarkable. In humans we would refer to such differences as personality traits.
From cowardly spiders and reckless salamanders to aggressive songbirds and fearless fish, we are finding that many animals are not as characterless as we might expect. What's more, work with animals has led to the idea that personality traits evolve to help individuals survive in a wider variety of ecological niches, and this is influencing the way psychologists think about human personality.
Read the original article: Critters with attitude (3 June 2001)
For an update on animal personalities and how research in this area is throwing light on human behaviour read The personality factor.