If there’s any molecule that is consistently viewed through rose-tinted glasses, it’s oxytocin. This simple hormone has earned misleading but charmingly alliterative nicknames like “hug hormone”, “cuddle chemical” and “moral molecule”. Writers love to claim, to the point of absurdity, that oxytocin increases trust, generosity, cooperation and empathy, among a slew of other virtues.
These lines of evidence might seem contradictory, but only if we hold the naive view that oxytocin is a chemical force for good. Instead, many scientists have suggested that, rather than some positive panacea, it’s more of a general social substance. It directs our attention towards socially relevant information – everything from facial expressions to posture – or drives us to seek out social interactions.
Now, Adam Reddon from McMaster University has found more evidence to support this idea by studying the daffodilcichlid, a beautiful African fish. When he injected them with isotocin – the fish version of oxytocin – he found that they became more responsive to social information. They were more sensitive to an opponent’s size before a fight, and they behaved more submissively when they themselves were challenged.
The social interactions that come naturally to most people are difficult for people with autism and Asperger syndrome. Simple matters like making eye contact, reading expressions and working out what someone else is thinking can be big challenges, even for “high-functioning” and intelligent individuals. Now, a preliminary study of 13 people suggests that some of these social difficulties could be temporarily relieved by inhaling a hormone called oxytocin.
The participants, who either had Asperger or high-functioning autism, experienced stronger feelings of trust, showed stronger social interactions in a simulated game, and paid more attention to socially important cues like someone else’s eyes. These results will need to be confirmed in larger studies in real-world situations, but for the moment, they’re promising.
Oxytocin is involved a myriad of emotions and social behaviours including trust, social interactions, sexual arousal, the bond between mother and child (see SciCurious’sepicoxytocinseriesformore). It has been linked to autism before. Autistic children have lower levels of the hormone coursing through their blood and what little there is appears to be made in an abnormal way. Some researchers are testing oxytocin as a treatment for some symptoms of autism, including repetitive behaviours, but the new results are some of the most interesting yet.
They say that imitation is the sincerest form of flattery and it appears that capuchins believe it too. These very sociable monkeys gravitate towards humans that mimic their actions, spending more time in their company and even preferring to trade with them.
Annika Paukner, who studied this monkey business, thinks that imitation is a type of social glue that binds groups of monkeys together. It says, “We are alike,” and in doing so, it lays the foundation for acts of selflessness by providing a means for two individuals to form an empathic connection.
Certainly, imitation is very much a part and parcel of human life. Every day, we mimic the gestures and mannerisms of people we meet. We sit in the same way, twirl our hair, shift our accents or scratch the same spot. This “chameleon effect” is almost always unconscious and while subtle, it can have a big impact on our social success. Others like us more if our behaviour matches their own, and we in turn put more unconscious effort into imitation if we want someone to like us or if sense that we’re being ostracised.
Paukner and other biologists suggest that these unconscious acts of imitation are adaptations to a social life and she wanted to see if imitation can also strengthen relationships in other sociable primates. Capuchins certainly fit the bill. Paukner allowed monkeys to play with a rubber ball while experimenters either matched their movements with their own balls or played in a different way. The animals spent significantly more time looking at the imitating human than the other one.
We get a lot of information from watching other people. We read reviews, we follow links to recommended websites and we listen when our friends vouch for strangers. The opinions of strangers may even be a better guide to the things that make us happy than our own predictions. But humans aren’t the only species to make decisions based on information gleaned from our peers – even animals as supposedly simple as flies can do the same.
Frederic Mery from LEGS (the Laboratory of Evolution, Genomes and Speciation) studied the fly Drosophila melanogaster and found that females have a tendency to follow the crowd. They are more attracted to male flies if other females crowd around him.
Following the crowd makes evolutionary sense; faced with uncertainty over the best males to mate with, females could do worse than to look at who their peers find sexiest. Female fish, birds, rats and possibly even humans are influenced in this way, but this is the first time that anyone has found the same behaviour among invertebrates.
Mery created two lines of male flies – a high-quality lineage raised on a nutritious diet, and a poor-quality one that grew up on much less food. Female flies were placed in a box along with one male from either group, each housed in his own transparent container. The female couldn’t touch the males, but she could see, smell and hear him. Based on that information alone, she could tell the studs from the weaklings and spent twice as much time buzzing over the high-quality male.
Moving to a new area can be a daunting experience, especially if you don’t know anyone. At first, you might cling to any friends who do live nearby but eventually, you meet new people and start to integrate. As it is with humans, so it is with elephants.
Noa Pinter-Wollman and colleagues from the University of California, Davis wanted to study how African elephants behave when they move to new environments. This happens quite naturally as elephants live in dynamic societies where small family groups continuously merge with, and separate from, each other. But they also face new territories with increasing regularity as human activity encroaches on their home ranges and forces them further afield, and as increasing conservation efforts lead to individuals being deliberately moved, or exchanged between zoos and wildlife parks.
Pinter-Wollman took advantage of just one such forced relocation to see how the animals would react. In September 2005, in an effort to reduce conflicts between humans and elephants, Kenya’s Wildlife Service moved 150 individuals from the Shimba Hills National Reserve to the Tsavo East National Park, some 160km away. They consisted of 20 groups of around 7 individuals each – mainly adult females and calves – and 20 independent males. Their new home was very different to their old one and Pinter-Wollman wanted to see how they reacted to it.