Tag Archives: Altruísmo

Chimps Catch Insects to Put on Wounds. Is It Folk Medicine? (New York Times)


Nicholas Bakalar


They don’t eat the bugs, and they’re definitely applying them to wounds, so some scientists think the primates may be treating one another’s injuries.
A chimp, Suzee, catches an insect and puts it on a wound on the foot of her son, Sia. Video by Alessandra Mascaro. Credit: Tobias Deschner

Feb. 7, 2022

A chimp, Suzee, catches an insect and puts it on a wound on the foot of her son, Sia. Video by Alessandra Mascaro. Credit: Tobias Deschner

Chimpanzees design and use tools. That is well known. But is it possible that they also use medicines to treat their own and others’ injuries? A new report suggests they do.

Since 2005, researchers have been studying a community of 45 chimpanzees in the Loango National Park in Gabon, on the west coast of Africa. Over a period of 15 months, from November 2019 to February 2021, the researchers saw 76 open wounds on 22 different chimpanzees. In 19 instances they watched a chimp performing what looked like self-treatment of the wound using an insect as a salve. In a few instances, one chimp appeared to treat another. The scientists published their observations in the journal Current Biology on Monday.

The procedure was similar each time. First, the chimps caught a flying insect; then they immobilized it by squeezing it between their lips. They placed the insect on the wound, moving it around with their fingertips. Finally, they took the insect out, using either their mouths or their fingers. Often, they put the insect in the wound and took it out several times.

The researchers do not know what insect the chimps were using, or precisely how it may help heal a wound. They do know that the bugs are small flying insects, dark in color. There’s no evidence that the chimps are eating the insects — they are definitely squeezing them with their lips and then applying them to the wounds.

There have been other reports of self-medication in animals, including dogs and cats that eat grass or plants, probably to help them vomit, and bears and deer that consume medicinal plants, apparently to self-medicate. Orangutans have been seen applying plant material to soothe muscle injuries. But the researchers know of no previous report of nonhuman mammals using insects for a medicinal purpose.

In three instances, the researchers saw chimps using the technique on another chimp. In one case, they saw an adult female named Carol grooming around a flesh wound on the leg of an adult male, Littlegrey. She grabbed an insect, and gave it to Littlegrey, who put it between his lips, and transferred it to his wound. Later, Carol and another adult male were seen moving the insect around on Littlegrey’s wound. Another adult male approached, took the insect out of the wound, put it between his own lips, then reapplied it to Littlegrey’s leg.

One chimp, an adult male named Freddy, was a particularly enthusiastic user of insect medicine, treating himself numerous times for injuries of his head, both arms, his lower back, his left wrist and his penis. One day, the researchers watched him treat himself twice for the same arm wound. The researchers don’t know how Freddy got these injuries, but some of them probably involved fighting with other males.

There are some animals that cooperate with others in similar ways, said Simone Pika, who leads an animal cognition lab at the University of Osnabrück in Germany and is an author of the study. “But we don’t know of any other instances in mammals,” she said. “This may be a learned behavior that exists only in this group. We don’t know if our chimps are special in this regard.”

Aaron Sandel, an anthropologist at the University of Texas, Austin, found the work valuable, but at the same time expressed some doubts. “They don’t offer an alternative explanation for the behavior, and they make no connection to what insect it might be,” he said. “The jump to a potential medical function? That’s a stretch at this point.”

Still, he said, “attending to their own wounds or the wounds of others using a tool, another object — that’s very rare.” Their documentation of chimps paying such attention to other chimps is, he added, “an important contribution to the study of social behavior in apes. And it’s still interesting to ask whether there is empathy involved in this, as it is in humans.”

In some forms of ape social behavior, it is clear that there is an exchange of value. For example, grooming another chimp provides relief from parasites for the groomed animal, but also an insect snack for the groomer. But in the instances she observed, Dr. Pika said, the chimp gets nothing tangible in return. To her, this shows the apes are engaging in an act that increases “the welfare of another being,” and teaches us more about the primates’ social relationships.

“With every field site we learn more about chimps,” she said. “They really surprise us.”

Face masks and the coronavirus: Masks probably slow the spread of covid-19 (The Economist)

But wearing one is mainly an act of altruism

Science & technology – May 28th 2020 edition

Editor’s note: Some of our covid-19 coverage is free for readers of The Economist Today, our daily newsletter. For more stories and our pandemic tracker, see our coronavirus hub

“THIS IS A, I would say, senseless dividing line,” said Doug Burgum, governor of North Dakota, his voice catching as he talked of the rows that have broken out in his state over the wearing of face-coverings. There are similar spats elsewhere in America, for masks have become the latest aspect of the culture war that has emerged there over how to deal with covid-19. Some shops refuse entry to maskwearers and Mike DeWine, the governor of Ohio, has rescinded an order requiring people to wear them, saying that he “went too far”.

Elsewhere in the world, by contrast, there is increasing acceptance that mask-wearing is a good thing. On May 5th, for example, the Royal Society, Britain’s top science academy, concluded that masks “could be an important tool for managing community transmission”. This is not so much because they protect the wearer—the normal reason people may put them on in times of pestilence—but rather because they stop the wearer infecting others.

In this context covid-19’s particular peculiarity—that people who test positive for it often do not have symptoms—is important. Research published last month in Nature Medicine, by Xi He of Guangzhou Medical University and Eric Lau of Hong Kong University, suggests that 44% of cases are caused by transmission from people without symptoms at the time of transmission.

Taking cover

Those who do have symptoms should not, of course, be out and about at all. In their case masks are irrelevant. But to break the chain, it behoves even the symptomless to assume that they might be infected. Covid-19 is transmitted, above all, by virus-laden droplets of spit. Experiments show that face-coverings as simple as tea-towels are effective. One study found that a tea-towel worn around the face captured 60% of droplets. At 75%, a surgical mask did better, but not overwhelmingly so.

Governments are beginning to take this on board. As part of the loosening their lockdown, the Dutch are required to wear face-coverings on public transport—but not ones of medical grade, which should be reserved for professionals. This encourages people to make their own.

Neither laboratory studies nor the data on asymptomatic transmission provide watertight evidence of the efficacy of masks. That would need randomised controlled trials, in which one group wore masks and the other did not. This would be ethically tricky, since it might condemn one of the groups to a higher death rate. Hamsters, which are susceptible to covid-19, are the next best thing to people. So researchers at Hong Kong University put cages of healthy hamsters next to cages of infected ones, with a fan in between drawing air from the infected to the healthy cage. They sometimes also placed a stretched-out face mask in the air stream. With no interposed mask, two-thirds of the healthy animals were infected within a week. With a mask interposed close to the healthy hamsters (the equivalent of a healthy person wearing a mask), one-third were. With the mask close to the infected hamsters, only a sixth were.

Although scientists cannot experiment on human beings deliberately, some wonder if the world is now carrying out a natural experiment that tests the value of mask-wearing. In many East Asian countries it was common practice to sport masks, even before covid-19, to protect against respiratory diseases and pollution. A lot of people in these places therefore took immediately to wearing masks when the epidemic started. Countries that adopted masks early on did not, by and large, shut their economies down. Yet they suppressed the disease more effectively than those that locked down but did not wear masks.

There is a correlation between mask-wearing and rapid suppression of covid-19. According to Patricia Greenhalgh, professor of primary health care sciences at Oxford University, “there is not a single country in which mask wearing was introduced early and with high compliance, where the disease wasn’t quickly brought under control.” Sceptics point out that this does not prove masks work, since countries in which they are widely worn also tend to be those which have been threatened by epidemics in the past, and therefore have well-established systems of testing and contact tracing.

In the West nobody normally wears a mask, though the practice is spreading. Universal masking started in the Czech Republic after Petr Ludwig, a Czech YouTube star, posted a video on March 14th recommending the practice, and it went viral. Other social-media influencers posted pictures of themselves wearing masks. “Mask trees”, where people would hang home-made masks for others to use, sprang up on street corners. By March 19th masks were mandatory in the country. Slovakia and Slovenia followed swiftly.

The World Health Organisation has not advocated widespread mask-wearing, and has received some criticism for this. Jeremy Howard, a research scientist at the University of San Francisco and co-founder of Masks4all, a charity, says “they did a good job of recommending handwashing and social distancing, but they have been slow on masks.”

In light of all this, regulations requiring people to wear masks have spread, as an increasing number of governments view the evidence as strong enough to warrant compulsion. India now requires them to be worn in crowded public spaces, as do France, Germany, Italy and Spain. In most of the world, people either wear them in such spaces without being told to, or are required to by their governments.

Among big countries, Britain and America are outliers. In Britain the government advises people to wear masks, but to little effect. On the London Underground around a third of travellers do so. On the Paris metro where people risk a €135 fine if they fail to cover their faces, everybody does. In America the Centres for Disease Control and Prevention, which previously recommended mask-wearing only for health workers, changed its mind in early April. It now recommends that everybody should wear them in places where it is hard for people to stay far enough apart. Several states have passed regulations along those lines, as has New York City. But, as Governor Burgum noted, the rows go on.■

This article appeared in the Science & technology section of the print edition under the headline “We interrupt this transmission…”

Darwinismo 2.0 (Valor Econômico)

JC e-mail 4976, de 24 de junho de 2014

Artigo de José Eli da Veiga publicado no Valor Econômico

Até o início dos anos 1980 o darwinismo foi amesquinhado pela concepção de que a sobrevivência dos mais aptos só decorreria da feroz competição que caracterizaria a “luta” pela existência. Por oitenta anos foi rejeitada a desviante interpretação das obras de Darwin proposta em “Ajuda Mútua: um Fator de Evolução”, livro com argutas observações sobre a extraordinária cooperação que caracteriza as vidas de abelhas, formigas e vários outros animais, publicado em 1902, no exílio londrino, pelo sessentão príncipe russo Piotr Kropotkin.

Mesmo que não tenha havido reconhecimento explícito, a perspicácia desse expoente do anarquismo começou a ser redimida quando um dos então mais promissores ramos da matemática – a Teoria dos Jogos – foi mobilizado para solucionar uma das questões que mais intrigava os pesquisadores, especialmente os das humanidades: num mundo de egoístas, desprovido de governo central, em que condições pode emergir a cooperação?

Resposta original e persuasiva foi dada em 1981 pelo cientista político da Universidade de Michigan, Robert Axelrod, que três anos depois lançou o hoje clássico “A Evolução da Cooperação” (Ed. Leopardo, 2010). Um livro que deveria tomar o lugar daquelas bíblias gratuitas achadas nos criados-mudos dos hotéis, diz Richard Dawkins, o célebre autor de “O Gene Egoísta” em prefácio à edição de 2006.

A proeza de Axelrod foi executar inéditas simulações computacionais que confirmaram hipóteses formuladas na década anterior por biólogos evolutivos: nepotismo e reciprocidade seriam os dois fatores determinantes da cooperação. Na ausência do primeiro, ela estaria na dependência de um padrão comportamental em que cada um dos atores repete o movimento do outro, reagindo positivamente a atitudes cooperativas e negativamente a gestos hostis.

Ainda em plena Guerra Fria, quando o risco de um “inverno nuclear” exigia a cooperação bipolar entre EUA e URSS, o que poderia fazer mais sucesso do que essa orientação apelidada de “tit-for-tat”, título de uma das populares comédias da dupla “O Gordo e o Magro”? Embora seja traduzida por “olho-por-olho, dente-por-dente”, essa expressão está mais próxima do “toma-lá-dá-cá”, pois é uma estratégia que exige prévio arranque cooperativo.

Como sempre ocorre na ciência, boa resposta a uma grande questão faz com que pipoquem novas dúvidas. Por exemplo: se por mera razão acidental um dos atores falhar em fazer o esperado movimento positivo, isso por si só inviabiliza a continuidade da cooperação? E o que ocorreria quando o esquema de cooperação envolvesse mais do que dois atores? Foram questões como essas que alavancaram o fulgurante avanço da biologia matemática nos últimos vinte anos. O padrão “toma-lá-dá-cá” hoje não passa de uma das três modalidades de uma das cinco dinâmicas de cooperação evidenciadas.

O “tit-for-tat” é manifestação rudimentar do que passou a ser chamado de “reciprocidade direta”. Novas simulações indicaram que eventual passo em falso pode engendrar uma segunda chance, em estratégia apelidada de “toma-lá-dá-cá generoso”, a origem evolutiva do perdão. E desdobramentos ainda mais sofisticados revelaram a existência de uma terceira forma de reciprocidade direta, na qual o agente inverte sua atitude anterior quando nota que as coisas vão mal, mas logo depois volta a cooperar. Algo que já era bem conhecido na etologia como comportamento “Win-Stay, Lose-Shift”, comum entre pombos, macacos, ratos e camundongos.

O segundo vetor da cooperação, chamado de “reciprocidade indireta”, foi crucial para a evolução da linguagem e para o próprio desenvolvimento do cérebro humano, pois se baseia no fenômeno da reputação. Neste caso, o que condiciona as atitudes dos atores são comportamentos anteriores em relações com terceiros. A cooperação avança quando a probabilidade de um agente se inteirar sobre a reputação do outro compensa o custo/benefício do ato altruísta.

Os demais determinantes da cooperação são as três formas em que ocorre a seleção natural, pois, além da já mencionada nepotista (de parentesco), ela não opera apenas entre indivíduos, mas também entre grupos (multinível) e nas redes (espacial).

Mesmo que as observações acima não sejam suficientes para que se possa ter uma boa ideia das descobertas da biologia matemática no âmbito da dinâmica evolutiva, elas certamente permitem notar que o darwinismo aponta tanto para “luta” quanto para “acomodação” pela existência. Exposição rigorosa e extremamente amigável desse darwinismo 2.0 está em “SuperCooperators – Altruism, Evolution, and Why We Need Each Other to Succeed” (Free Press, 2011), do austríaco Martin A. Nowak, biólogo matemático que está em Harvard depois de ter brilhado em Oxford e Princeton, e que contou com a inestimável ajuda do jornalista científico britânico Roger Highfield.

Esse sim é um livro que mereceria ser distribuído gratuitamente. Não para substituir bíblias cristãs, mas para promover o entendimento das origens naturais dos códigos de ética de todas as grandes religiões.

José Eli da Veiga é professor sênior do Instituto de Energia e Ambiente da USP e autor de “A desgovernança mundial da sustentabilidade” (Editora 34, 2013). Escreve mensalmente às terças-feiras. http://www.zeeli.pro.br

(Valor Econômico)

Brain Can Be Trained in Compassion, Study Shows (Science Daily)

May 22, 2013 — Until now, little was scientifically known about the human potential to cultivate compassion — the emotional state of caring for people who are suffering in a way that motivates altruistic behavior.

Investigators trained young adults to engage in compassion meditation, an ancient Buddhist technique to increase caring feelings for people who are suffering. (Credit: © byheaven / Fotolia)

A new study by researchers at the Center for Investigating Healthy Minds at the Waisman Center of the University of Wisconsin-Madison shows that adults can be trained to be more compassionate. The report, published Psychological Science, a journal of the Association for Psychological Science, investigates whether training adults in compassion can result in greater altruistic behavior and related changes in neural systems underlying compassion.

“Our fundamental question was, ‘Can compassion be trained and learned in adults? Can we become more caring if we practice that mindset?'” says Helen Weng, lead author of the study and a graduate student in clinical psychology. “Our evidence points to yes.”

In the study, the investigators trained young adults to engage in compassion meditation, an ancient Buddhist technique to increase caring feelings for people who are suffering. In the meditation, participants envisioned a time when someone has suffered and then practiced wishing that his or her suffering was relieved. They repeated phrases to help them focus on compassion such as, “May you be free from suffering. May you have joy and ease.”

Participants practiced with different categories of people, first starting with a loved one, someone whom they easily felt compassion for, like a friend or family member. Then, they practiced compassion for themselves and, then, a stranger. Finally, they practiced compassion for someone they actively had conflict with called the “difficult person,” such as a troublesome coworker or roommate.

“It’s kind of like weight training,” Weng says. “Using this systematic approach, we found that people can actually build up their compassion ‘muscle’ and respond to others’ suffering with care and a desire to help.”

Compassion training was compared to a control group that learned cognitive reappraisal, a technique where people learn to reframe their thoughts to feel less negative. Both groups listened to guided audio instructions over the Internet for 30 minutes per day for two weeks. “We wanted to investigate whether people could begin to change their emotional habits in a relatively short period of time,” says Weng.

The real test of whether compassion could be trained was to see if people would be willing to be more altruistic — even helping people they had never met. The research tested this by asking the participants to play a game in which they were given the opportunity to spend their own money to respond to someone in need (called the “Redistribution Game”). They played the game over the Internet with two anonymous players, the “Dictator” and the “Victim.” They watched as the Dictator shared an unfair amount of money (only $1 out of $10) with the Victim. They then decided how much of their own money to spend (out of $5) in order to equalize the unfair split and redistribute funds from the Dictator to the Victim.

“We found that people trained in compassion were more likely to spend their own money altruistically to help someone who was treated unfairly than those who were trained in cognitive reappraisal,” Weng says.

“We wanted to see what changed inside the brains of people who gave more to someone in need. How are they responding to suffering differently now?” asks Weng. The study measured changes in brain responses using functional magnetic resonance imaging (fMRI) before and after training. In the MRI scanner, participants viewed images depicting human suffering, such as a crying child or a burn victim, and generated feelings of compassion towards the people using their practiced skills. The control group was exposed to the same images, and asked to recast them in a more positive light as in reappraisal.

The researchers measured how much brain activity had changed from the beginning to the end of the training, and found that the people who were the most altruistic after compassion training were the ones who showed the most brain changes when viewing human suffering. They found that activity was increased in the inferior parietal cortex, a region involved in empathy and understanding others. Compassion training also increased activity in the dorsolateral prefrontal cortex and the extent to which it communicated with the nucleus accumbens, brain regions involved in emotion regulation and positive emotions.

“People seem to become more sensitive to other people’s suffering, but this is challenging emotionally. They learn to regulate their emotions so that they approach people’s suffering with caring and wanting to help rather than turning away,” explains Weng.

Compassion, like physical and academic skills, appears to be something that is not fixed, but rather can be enhanced with training and practice. “The fact that alterations in brain function were observed after just a total of seven hours of training is remarkable,” explains UW-Madison psychology and psychiatry professor Richard J. Davidson, founder and chair of the Center for Investigating Healthy Minds and senior author of the article.

“There are many possible applications of this type of training,” Davidson says. “Compassion and kindness training in schools can help children learn to be attuned to their own emotions as well as those of others, which may decrease bullying. Compassion training also may benefit people who have social challenges such as social anxiety or antisocial behavior.”

Weng is also excited about how compassion training can help the general population. “We studied the effects of this training with healthy participants, which demonstrated that this can help the average person. I would love for more people to access the training and try it for a week or two — what changes do they see in their own lives?”

Both compassion and reappraisal trainings are available on the Center for Investigating Healthy Minds’ website. “I think we are only scratching the surface of how compassion can transform people’s lives,” says Weng.

Other authors on the paper were Andrew S. Fox, Alexander J. Shackman, Diane E. Stodola, Jessica Z. K. Caldwell, Matthew C. Olson, and Gregory M. Rogers.

The work was supported by funds from the National Institutes of Health; a Hertz Award to the UW-Madison Department of Psychology; the Fetzer Institute; The John Templeton Foundation; the Impact Foundation; the J. W. Kluge Foundation; the Mental Insight Foundation; the Mind and Life Institute; and gifts from Bryant Wanguard, Ralph Robinson, and Keith and Arlene Bronstein.

Journal Reference:

  1. H. Y. Weng, A. S. Fox, A. J. Shackman, D. E. Stodola, J. Z. K. Caldwell, M. C. Olson, G. M. Rogers, R. J. Davidson.Compassion Training Alters Altruism and Neural Responses to SufferingPsychological Science, 2013; DOI: 10.1177/0956797612469537

‘Networked Minds’ Require Fundamentally New Kind of Economics (Science Daily)

Mar. 20, 2013 — In their computer simulations of human evolution, scientists at ETH Zurich find the emergence of the “homo socialis” with “other-regarding” preferences. The results explain some intriguing findings in experimental economics and call for a new economic theory of “networked minds”.

In their computer simulations of human evolution, scientists at ETH Zurich find the emergence of the “homo socialis” with “other-regarding” preferences. The results explain some intriguing findings in experimental economics and call for a new economic theory of “networked minds”. (Credit: © violetkaipa / Fotolia)

Economics has a beautiful body of theory. But does it describe real markets? Doubts have come up not only in the wake of the financial crisis, since financial crashes should not occur according to the then established theories. Since ages, economic theory is based on concepts such as efficient markets and the “homo economicus”, i.e. the assumption of competitively optimizing individuals and firms. It was believed that any behavior deviating from this would create disadvantages and, hence, be eliminated by natural selection. But experimental evidence from behavioral economics show that, on average, people behave more fairness-oriented and other-regarding than expected. A new theory by scientists from ETH Zurich now explains why.

“We have simulated interactions of individuals facing social dilemma situations, where it would be favorable for everyone to cooperate, but non-cooperative behavior is tempting,” explains Dr. Thomas Grund, one of the authors of the study. “Hence, cooperation tends to erode, which is bad for everyone.” This may create tragedies of the commons such as over-fishing, environmental pollution, or tax evasion.

Evolution of “friendliness”

Prof. Dirk Helbing of ETH Zurich, who coordinated the study, adds: “Compared to conventional models for the evolution of social cooperation, we have distinguished between the actual behavior – cooperation or not – and an inherited character trait, describing the degree of other-regarding preferences, which we call the friendliness.” The actual behavior considers not only the own advantage (“payoff”), but also gives a weight to the payoff of the interaction partners depending on the individual friendliness. For the “homo economicus”, the weight is zero. The friendliness spreads from one generation to the next according to natural selection. This is merely based on the own payoff, but mutations happen.

For most parameter combinations, the model predicts the evolution of a payoff-maximizing “homo economicus” with selfish preferences, as assumed by a great share of the economic literature. Very surprisingly, however, biological selection may create a “homo socialis” with other-regarding preferences, namely if offsprings tend to stay close to their parents. In such a case, clusters of friendly people, who are “conditionally cooperative”, may evolve over time.

If an unconditionally cooperative individual is born by chance, it may be exploited by everyone and not leave any offspring. However, if born in a favorable, conditionally cooperative environment, it may trigger cascade-like transitions to cooperative behavior, such that other-regarding behavior pays off. Consequently, a “homo socialis” spreads.

Networked minds create a cooperative human species

“This has fundamental implications for the way, economic theories should look like,” underlines Professor Helbing. Most of today’s economic knowledge is for the “homo economicus”, but people wonder whether that theory really applies. A comparable body of work for the “homo socialis” still needs to be written.

While the “homo economicus” optimizes its utility independently, the “homo socialis” puts himself or herself into the shoes of others to consider their interests as well,” explains Grund, and Helbing adds: “This establishes something like “networked minds”. Everyone’s decisions depend on the preferences of others.” This becomes even more important in our networked world.

A participatory kind of economy

How will this change our economy? Today, many customers doubt that they get the best service by people who are driven by their own profits and bonuses. “Our theory predicts that the level of other-regarding preferences is distributed broadly, from selfish to altruistic. Academic education in economics has largely promoted the selfish type. Perhaps, our economic thinking needs to fundamentally change, and our economy should be run by different kinds of people,” suggests Grund. “The true capitalist has other-regarding preferences,” adds Helbing, “as the “homo socialis” earns much more payoff.” This is, because the “homo socialis” manages to overcome the downwards spiral that tends to drive the “homo economicus” towards tragedies of the commons. The breakdown of trust and cooperation in the financial markets back in 2008 might be seen as good example.

“Social media will promote a new kind of participatory economy, in which competition goes hand in hand with cooperation,” believes Helbing. Indeed, the digital economy’s paradigm of the “prosumer” states that the Internet, social platforms, 3D printers and other developments will enable the co-producing consumer. “It will be hard to tell who is consumer and who is producer”, says Christian Waloszek. “You might be both at the same time, and this creates a much more cooperative perspective.”

Journal Reference:

  1. Thomas Grund, Christian Waloszek, Dirk Helbing. How Natural Selection Can Create Both Self- and Other-Regarding Preferences, and Networked Minds.Scientific Reports, 2013; 3 DOI: 10.1038/srep01480

Some Plants Are Altruistic, Too, New Study Suggests (Science Daily)

Feb. 1, 2013 — We’ve all heard examples of animal altruism: Dogs caring for orphaned kittens, chimps sharing food or dolphins nudging injured mates to the surface. Now, a study led by the University of Colorado Boulder suggests some plants are altruistic too.

A new study led by CU-Boulder involving graduate student Chi-Chih Wu, shown here, indicates corn plants may have an altruistic side. (Credit: Photo courtesy CU-Boulder)

The researchers looked at corn, in which each fertilized seed contained two “siblings” — an embryo and a corresponding bit of tissue known as endosperm that feeds the embryo as the seed grows, said CU-Boulder Professor Pamela Diggle. They compared the growth and behavior of the embryos and endosperm in seeds sharing the same mother and father with the growth and behavior of embryos and endosperm that had genetically different parents.

“The results indicated embryos with the same mother and father as the endosperm in their seed weighed significantly more than embryos with the same mother but a different father,” said Diggle, a faculty member in CU-Boulder’s ecology and evolutionary biology department. “We found that endosperm that does not share the same father as the embryo does not hand over as much food — it appears to be acting less cooperatively.”

A paper on the subject was published during the week of Jan. 21 in the Proceedings of the National Academy of Sciences. Co-authors on the study included Chi-Chih Wu, a CU-Boulder doctoral student in the ecology and evolutionary biology department and Professor William “Ned” Friedman, a professor at Harvard University who helped conduct research on the project while a faculty member at CU-Boulder.

Diggle said it is fairly clear from previous research that plants can preferentially withhold nutrients from inferior offspring when resources are limited. “Our study is the first to specifically test the idea of cooperation among siblings in plants.”

“One of the most fundamental laws of nature is that if you are going to be an altruist, give it up to your closest relatives,” said Friedman. “Altruism only evolves if the benefactor is a close relative of the beneficiary. When the endosperm gives all of its food to the embryo and then dies, it doesn’t get more altruistic than that.”

In corn reproduction, male flowers at the top of the plants distribute pollen grains two at a time through individual tubes to tiny cobs on the stalks covered by strands known as silks in a process known as double fertilization. When the two pollen grains come in contact with an individual silk, they produce a seed containing an embryo and endosperm. Each embryo results in just a single kernel of corn, said Diggle.

The team took advantage of an extremely rare phenomenon in plants called “hetero-fertilization,” in which two different fathers sire individual corn kernels, said Diggle, currently a visiting professor at Harvard. The manipulation of corn plant genes that has been going on for millennia — resulting in the production of multicolored “Indian corn” cobs of various colors like red, purple, blue and yellow — helped the researchers in assessing the parentage of the kernels, she said.

Wu, who cultivated the corn and harvested more than 100 ears over a three-year period, removed, mapped and weighed every individual kernel out of each cob from the harvests. While the majority of kernels had an endosperm and embryo of the same color — an indication they shared the same mother and father — some had different colors for each, such as a purple outer kernel with yellow embryo.

Wu was searching for such rare kernels — far less than one in 100 — that had two different fathers as a way to assess cooperation between the embryo and endosperm. “It was very challenging and time-consuming research,” said Friedman. “It was like looking for a needle in a haystack, or in this case, a kernel in a silo.”

Endosperm — in the form of corn, rice, wheat and other crops — is critical to humans, providing about 70 percent of calories we consume annually worldwide. “The tissue in the seeds of flowering plants is what feeds the world,” said Friedman, who also directs the Arnold Arboretum at Harvard. “If flowering plants weren’t here, humans wouldn’t be here.”

Journal Reference:

  1. K. Baruch, N. Ron-Harel, H. Gal, A. Deczkowska, E. Shifrut, W. Ndifon, N. Mirlas-Neisberg, M. Cardon, I. Vaknin, L. Cahalon, T. Berkutzki, M. P. Mattson, F. Gomez-Pinilla, N. Friedman, M. Schwartz. CNS-specific immunity at the choroid plexus shifts toward destructive Th2 inflammation in brain aging.Proceedings of the National Academy of Sciences, 2013; DOI: 10.1073/pnas.1211270110

Bonobos Will Share With Strangers Before Acquaintances (Science Direct)

Jan. 2, 2013 — You’re standing in line somewhere and you decide to open a pack of gum. Do you share a piece with the coworker standing to one side of you, or with the stranger on the other?

This is an infant bonobo feeding on papaya. (Credit: Jingzhi Tan)

Most humans would choose the person they know first, if they shared at all.

But bonobos, those notoriously frisky, ardently social great apes of the Congo, prefer to share with a stranger before sharing with an animal they know. In fact, a bonobo will invite a stranger to share a snack while leaving an acquaintance watching helplessly from behind a barrier.

“It seems kind of crazy to us, but bonobos prefer to share with strangers,” said Brian Hare, a professor of evolutionary anthropology at Duke University. “They’re trying to extend their social network.” And they apparently value that more than maintaining the friendships they already have.

To measure this willingness to share, Hare and graduate student Jingzhi Tan ran a series of experiments with bonobos living in the Lola ya Bonobo sanctuary in Kinshasa, Democratic Republic of Congo. The experiments involved piles of food and enclosures that the test subjects were able to unlock and open. Tan and Hare describe their work in a paper in the Jan. 2, 2013 edition of PLOS ONE.

In the first series of experiments, a pile of food was placed in a central enclosure flanked by two enclosures, each of them holding another animal. The test subject had the knowledge and ability to open a door to either of the other chambers, or both. On one side was a bonobo they knew from their group (not necessarily a friend or family member) and in the other was a bonobo they had never really met, but had only seen at a distance.

Upon entering the chamber with the food, the test subjects could easily just sit down and consume it all themselves, or they could let in one or both of the other animals to share.

Nine of the 14 animals who went through this test released the stranger first. Two preferred their groupmates. Three showed no particular preference in repeated trials. The third animal was often let in on the treat as well, but more often it was the stranger, not the test subject, who opened the door for them.

Tan said that by letting the third animal into the enclosure, the stranger voluntarily outnumbered himself or herself with two bonobos who knew each other, which a chimpanzee would never do. In 51 trials of the experiment, there was never any aggression shown, although there was quite a bit of typical bonobo genital rubbing between the strangers.

To isolate how much motivation the animals receive from social interaction, the researchers ran a second set of experiments in which the subject animal wouldn’t receive any social contact with another animal. In the first of these experiments, the subjects couldn’t get any food for themselves regardless of whether they chose to open the door to allow the other animal to get some food. Nine out of ten animals shared with the stranger at least once.

In the final experiment without social contact, the subject animal was given access to the food in such a way that opening the door to share with the other animal would cost them some food. But they still wouldn’t have any social contact as a reward. In this instance, the animals chose not to share. “If they’re not going to see a social benefit, they won’t share,” Hare said.

This second test is similar to something called the dictator game in which humans are given the chance to share cash with a stranger, Hare said. Most people will share anonymously, but they share even more when they aren’t anonymous. Bonobos won’t share at all in the anonymous condition if it costs them food.

“They care about others,” Hare said, but only in a sort of selfish way. “They’ll share when it’s a low-cost/low-benefit kind of situation. But when it’s a no-benefit situation, they won’t share. That’s different from a human playing the dictator game. You really have to care about others to give anonymously.”

The findings, which Hare calls “one of the crazier things we’ve found” in more than a decade of bonobo research, form yet another distinction between bonobos and chimpanzees, our two closest relatives. “Chimps can’t do these tests, they’d be all over each other.”

The work was funded by the National Science Foundation and the European Research Council.

Journal Reference:

  1. Tan J, Hare B. Bonobos Share with StrangersPLOS ONE, 2013; 8 (1): e51922 DOI:10.1371/journal.pone.0051922

Lost Letter Experiment Suggests Wealthy London Neighborhoods Are ‘More Altruistic’ (Science Daily)

ScienceDaily (Aug. 15, 2012) — Neighbourhood income deprivation has a strong negative effect on altruistic behaviour when measured by a ‘lost letter’ experiment, according to new UCL research published August 15 in PLoS One.

Researchers from UCL Anthropology used the lost letter technique to measure altruism across 20 London neighbourhoods by dropping 300 letters on the pavement and recording whether they arrived at their destination. The stamped letters were addressed by hand to a study author’s home address with a gender neutral name, and were dropped face-up and during rain free weekdays.

The results show a strong negative effect of neighbourhood income deprivation on altruistic behaviour, with an average of 87% of letters dropped in the wealthier neighbourhoods being returned compared to only an average 37% return rate in poorer neighbourhoods.

Co-author Jo Holland said: “This is the first large scale study investigating cooperation in an urban environment using the lost letter technique. This technique, first used in the 1960s by the American social psychologist Stanley Milgram, remains one of the best ways of measuring truly altruistic behaviour, as returning the letter doesn’t benefit that person and actually incurs the small hassle of taking the letter to a post box.

Co-author Professor Ruth Mace added: “Our study attempts to understand how the socio-economic characteristics of a neighbourhood affect the likelihood of people in a neighbourhood acting altruistically towards a stranger. The results show a clear trend, with letters dropped in the poorest neighbourhoods having 91% lower odds of being returned than letters dropped in the wealthiest neighbourhoods. This suggests that those living in poor neighbourhoods are less inclined to behave altruistically toward their neighbours.”

As well as measuring the number of letters returned, the researchers also looked at how other neighbourhood characteristics may help to explain the variation in altruistic behaviour — including ethnic composition and population density — but did not find them to be good predictors of lost letter return.

Corresponding author Antonio Silva said: “The fact that ethnic composition does not play a role on the likelihood of a letter being returned is particularly interesting, as other studies have suggested that ethnic mixing negatively affects social cohesion, but in our sampled London neighbourhoods this does not appear to be true.

“The level of altruism observed in a population is likely to vary according to its context. Our hypothesis that area level socio-economic characteristics could determine the levels of altruism found in individuals living in an area is confirmed by our results. Our overall findings replicate and expand on previous studies which use similar methodology.

“We show in this study that individuals living in poor neighbourhoods are less altruistic than individuals in wealthier neighbourhoods. However, the effect of income deprivation may be confounded by crime, as the poorer neighbourhoods tend to have higher rates crime which may lead to people in those neighbourhoods being generally more suspicious and therefore less likely to pick up a lost letter.

“Further research should focus on attempting to disentangle these two factors, possibly by comparing equally deprived neighbourhoods with different levels of crime. Although this study uses only one measure of altruism and therefore we should be careful in interpreting these findings, it does give us an interesting perspective on altruism in an urban context and provides a sound experimental model on which to base future studies.”

Interest in Arts Predicts Social Responsibility (Science Daily)

ScienceDaily (Aug. 16, 2012) — If you sing, dance, draw, or act — and especially if you watch others do so — you probably have an altruistic streak, according to a study by researchers at the University of Illinois at Chicago.

People with an active interest in the arts contribute more to society than those with little or no such interest, the researchers found. They analyzed arts exposure, defined as attendance at museums and dance, music, opera and theater events; and arts expression, defined as making or performing art.

“Even after controlling for age, race and education, we found that participation in the arts, especially as audience, predicted civic engagement, tolerance and altruism,” said Kelly LeRoux, assistant professor of public administration at UIC and principal investigator on the study.

In contrast to earlier studies, Generation X respondents were found to be more civically engaged than older people.

LeRoux’s data came from the General Social Survey, conducted since 1972 by the National Data Program for the Sciences, known by its original initials, NORC. A national sample of 2,765 randomly selected adults participated.

“We correlated survey responses to arts-related questions to responses on altruistic actions — like donating blood, donating money, giving directions, or doing favors for a neighbor — that place the interests of others over the interests of self,” LeRoux said. “We looked at ‘norms of civility.’ Previous studies have established norms for volunteering and being active in organizations.”

The researchers measured participation in neighborhood associations, church and religious organizations, civic and fraternal organizations, sports groups, charitable organizations, political parties, professional associations and trade unions.

They measured social tolerance by two variables:

  • Gender-orientation tolerance, measured by whether respondents would agree to having gay persons speak in their community or teach in public schools, and whether they would oppose having homosexually themed books in the library.
  • Racial tolerance, measured by responses regarding various racial and ethnic groups, including African-Americans, Hispanics, and Asian Americans. Eighty percent of the study respondents were Caucasian, LeRoux said.

The researchers measured altruistic behavior by whether respondents said they had allowed a stranger to go ahead of them in line, carried a stranger’s belongings, donated blood, given directions to a stranger, lent someone an item of value, returned money to a cashier who had given too much change, or looked after a neighbor’s pets, plants or mail.

“If policymakers are concerned about a decline in community life, the arts shouldn’t be disregarded as a means to promote an active citizenry,” LeRoux said. “Our positive findings could strengthen the case for government support for the arts.”

The study was based on data from 2002, the most recent year in which the General Social Survey covered arts participation. LeRoux plans to repeat the study with results from the 2012 survey, which will include arts data.