‘Moral Realism’ May Lead to Better Moral Behavior

Jan. 29, 2013 — Getting people to think about morality as a matter of objective facts rather than subjective preferences may lead to improved moral behavior, Boston College researchers report in the Journal of Experimental Social Psychology.


 

In two experiments, one conducted in-person and the other online, participants were primed to consider a belief in either moral realism (the notion that morals are like facts) or moral antirealism (the belief that morals reflect people’s preferences) during a solicitation for a charitable donation. In both experiments, those primed with moral realism pledged to give more money to the charity than those primed with antirealism or those not primed at all.

“There is significant debate about whether morals are processed more like objective facts, like mathematical truths, or more like subjective preferences similar to whether vanilla or chocolate tastes better,” said lead researcher Liane Young, assistant professor of psychology at Boston College. “We wanted to explore the impact of these different meta-ethical views on actual behavior.”

Ideas have previously been advanced on the subject, but Young and her former research assistant A.J. Durwin, now a law student at Hofstra University, are the first to directly investigate the question.

In one experiment, a street canvasser attempted to solicit donations from passersby for a charity that aids impoverished children. Participants in one set were asked a leading question to prime a belief in moral realism: “Do you agree that some things are just morally right or wrong, good or bad, wherever you happen to be from in the world?” Those in a second set were asked a question to prime belief in moral antirealism: “Do you agree that our morals and values are shaped by our culture and upbringing, so there are no absolute right answers to any moral questions?” Participants in a control set were not asked any priming question.

In this experiment, participants primed with realism were twice as likely to be donors, compared to those primed with antirealism or not primed at all.

A second experiment, conducted online, yielded similar results. Participants asked to donate money to a charity of their choice who were primed with realism reported being willing to give more than those primed with antirealism or not primed at all.

“Priming participants to consider the notion that morals are like facts increased decisions to donate in both experiments, revealing the potential impact of meta-ethical views on everyday decision-making,” said Young. “Simply asking participants to consider moral values, as we did with the antirealism prime, did not produce an effect,” she said, “so priming morality in general may not necessarily lead to better behavior. Considering the existence of non-negotiable moral facts may have raised the stakes and motivated participants to behave better.”

Since “real” moral stakes may be accompanied by “real” consequences — whether good (e.g., helping others, enhanced self-esteem) or bad (e.g., retribution), priming a belief in moral realism may in fact prompt people to behave better, in line with their existing moral beliefs, the researchers say.

The researchers note that priming a belief in moral realism may enhance moral behavior under certain conditions — such as when the right thing to do is relatively unambiguous (e.g., it is good to be generous). A different outcome could be possible when subjects are faced with more controversial moral issues, they say.

Liane Young’s research frequently focuses on the psychology and neuroscience of moral judgment and behavior. In 2012, she was awarded a Sloan Research Fellowship from the Alfred P. Sloan Foundation, and was named a Dana Neuroscience Scholar by the Dana Foundation, which also awarded her a three-year grant to support her study of brain activity and moral decision-making in individuals with autism, a project that will provide a valuable research opportunity for BC undergraduates. In addition, she received the 2011 Early Career Award for Distinguished Scientific Contributions to Social Neuroscience from the Society for Social Neuroscience, among other honors.

Her research on attributions of responsibility to groups (e.g., corporations) versus members of groups was published in the journal Psychological Science in 2012; she is also co-author of a study of moral judgments in adults with autism that was reported in the Proceedings of the National Academy of Sciences.


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The above story is reprinted from materials provided byBoston College, via EurekAlert!, a service of AAAS.

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Journal Reference:

  1. Liane Young, A.J. Durwin. Moral realism as moral motivation: The impact of meta-ethics on everyday decision-makingJournal of Experimental Social Psychology, 2013; 49 (2): 302 DOI:10.1016/j.jesp.2012.11.013
Boston College (2013, January 29). ‘Moral realism’ may lead to better moral behavior.ScienceDaily. Retrieved January 30, 2013, from http://www.sciencedaily.com/releases/2013/01/130129121939.htm
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Cultural Evolution Changes Bird Song

Jan. 29, 2013 — Thanks to cultural evolution, male Savannah sparrows are changing their tune, partly to attract “the ladies.”


 

According to a study of more than 30 years of Savannah sparrows recordings, the birds are singing distinctly different songs today than their ancestors did 30 years ago — changes passed along generation to generation, according to a new study by University of Guelph researchers.

Integrative biology professors Ryan Norris and Amy Newman, in collaboration with researchers at Bowdoin College and Williams College in the U.S., analyzed the songs of male Savannah sparrows (Passerculus sandwichiensis) recorded over three decades, and found that the songs had changed distinctly from 1980 to 2011.

“The change is the result of cultural transmission of different song elements through many generations,” said Norris.

Norris added that the change in tune resembles changes in word choice and language among humans.

“If you listen to how people used to talk in the 1890s and how we talk today, you would notice major differences, and this is the result of shifts in culture or the popularity of certain forms,” he said. “The change in sparrow songs over time has occurred much the same way”

The sparrows, which live on Kent Island, N.B., in the Bay of Fundy, can generally sing only one song type that consists of several parts. Male sparrows learn that song early in their first year and continue to sing the same tune for the rest of their lives.

“Young male sparrows learn their songs from the birds around them,” said Norris. “It may be their fathers, or it could be other older male birds that live nearby.”

Each male sparrow has his own unique sound, added Newman.

“While the island’s sparrows all sing a characteristic ‘savannah sparrow song,’ with the same verses and sound similar, there are distinct differences between each bird,” she said. “Essentially, it is like karaoke versions of popular songs. It is the rise and fall in popular cover versions that has changed over time.”

The research team found that, in general, each song has three primary elements. The first identifies the bird as a Savannah sparrow, the second identifies which individual is singing, and the third component is used by females to assess males.

Using sonograms recorded from singing males each breeding season, the researchers determined that, while the introductory notes had stayed generally consistent for the last 30 years, the sparrows had added a series of clicks to the middle of their songs. The birds had also changed the ending trill: once long and high-frequency, it is now shorter and low-frequency.

“We found that the ending trill of the song has become shorter, likely because female sparrows preferred this, because males with shorter trills had higher reproductive success,” Norris said.

Kent Island has been home to the Bowdoin Scientific Station since it was donated by J. Sterling Rockefeller in 1932, and the birds have been recorded since the 1980s. Individual birds are also monitored throughout their lifetime.

“We know the identity and history of every single sparrow in the study population” said Norris, who has led the project with Newman since 2009. “To have 30 years of recordings is very rare, and it was definitely surprising to see such drastic changes.”

 

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The above story is reprinted from materials provided byUniversity of Guelph.

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Journal Reference:

  1. Heather Williams, Iris I. Levin, D. Ryan Norris, Amy E.M. Newman, Nathaniel T. Wheelwright. Three decades of cultural evolution in Savannah sparrow songsAnimal Behaviour, 2013; 85 (1): 213 DOI:10.1016/j.anbehav.2012.10.028
University of Guelph (2013, January 29). Cultural evolution changes bird song.ScienceDaily. Retrieved January 30, 2013, from http://www.sciencedaily.com/releases/2013/01/130129121937.htm

Could the Timing of When You Eat, Be Just as Important as What You Eat?

Jan. 29, 2013 — Most weight-loss plans center around a balance between caloric intake and energy expenditure. However, new research has shed light on a new factor that is necessary to shed pounds: timing. Researchers from Brigham and Women’s Hospital (BWH), in collaboration with the University of Murcia and Tufts University, have found that it’s not simply what you eat, but also when you eat, that may help with weight-loss regulation.


 

The study will be published on January 29, 2013 in the International Journal of Obesity.

“This is the first large-scale prospective study to demonstrate that the timing of meals predicts weight-loss effectiveness,” said Frank Scheer, PhD, MSc, director of the Medical Chronobiology Program and associate neuroscientist at BWH, assistant professor of medicine at Harvard Medical School, and senior author on this study. “Our results indicate that late eaters displayed a slower weight-loss rate and lost significantly less weight than early eaters, suggesting that the timing of large meals could be an important factor in a weight loss program.”

To evaluate the role of food timing in weight-loss effectiveness, the researchers studied 420 overweight study participants who followed a 20-week weight-loss treatment program in Spain. The participants were divided into two groups: early-eaters and late-eaters, according to the self-selected timing of the main meal, which in this Mediterranean population was lunch. During this meal, 40 percent of the total daily calories are consumed. Early-eaters ate lunch anytime before 3 p.m. and late-eaters, after 3 p.m. They found that late-eaters lost significantly less weight than early-eaters, and displayed a much slower rate of weight-loss. Late-eaters also had a lower estimated insulin sensitivity, a risk factor for diabetes.

Researchers found that timing of the other (smaller) meals did not play a role in the success of weight loss. However, the late eaters — who lost less weight — also consumed fewer calories during breakfast and were more likely to skip breakfast altogether. Late-eaters also had a lower estimated insulin sensitivity, a risk factor for diabetes.

The researchers also examined other traditional factors that play a role in weight loss such as total calorie intake and expenditure, appetite hormones leptin and ghrelin, and sleep duration. Among these factors, researchers found no differences between both groups, suggesting that the timing of the meal was an important and independent factor in weight loss success.

“This study emphasizes that the timing of food intake itself may play a significant role in weight regulation” explains Marta Garaulet, PhD, professor of Physiology at the University of Murcia Spain, and lead author of the study. “Novel therapeutic strategies should incorporate not only the caloric intake and macronutrient distribution, as it is classically done, but also the timing of food.”


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The above story is reprinted from materials provided byBrigham and Women’s Hospital, via EurekAlert!, a service of AAAS.

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Journal Reference:

  1. M Garaulet, P Gómez-Abellán, J J Alburquerque-Béjar, Y-C Lee, J M Ordovás, F A J L Scheer. Timing of food intake predicts weight loss effectivenessInternational Journal of Obesity, 2013; DOI: 10.1038/ijo.2012.229
Brigham and Women’s Hospital (2013, January 29). Could the timing of when you eat, be just as important as what you eat?. ScienceDaily. Retrieved January 30, 2013, from http://www.sciencedaily.com/releases/2013/01/130129080620.htm

Survival of the Prettiest: Sexual Selection Can Be Inferred from the Fossil Record

Jan. 29, 2013 — Detecting sexual selection in the fossil record is not impossible, according to scientists writing in Trends in Ecology and Evolution this month, co-authored by Dr Darren Naish of the University of Southampton.


 

The term “sexual selection” refers to the evolutionary pressures that relate to a species’ ability to repel rivals, meet mates and pass on genes. We can observe these processes happening in living animals but how do palaeontologists know that sexual selection operated in fossil ones?

Historically, palaeontologists have thought it challenging, even impossible, to recognise sexual selection in extinct animals. Many fossil animals have elaborate crests, horns, frills and other structures that look like they were used in sexual display but it can be difficult to distinguish these structures from those that might play a role in feeding behaviour, escaping predators, controlling body temperature and so on.

However in their review, the scientists argue that clues in the fossil record can indeed be used to infer sexual selection.

“We see much evidence from the fossil record suggesting that sexual selection played a major role in the evolution of many extinct groups,” says Dr Naish, of the University’s Vertebrate Palaeontology Research Group.

“Using observations of modern animal behaviour we can draw analogies with extinct animals and infer how certain features improve success during courtship and breeding.”

Modern examples of sexual selection, where species have evolved certain behaviours or ornamentation that repel rivals and attract members of the opposite sex, include the male peacock’s display of feathers, and the male moose’s antlers for use in clashes during mating season.

Dr Naish and co-authors state that the fossil record holds many clues that point to the existence of sexual selection in extinct species, for example weaponry for fighting, bone fractures from duels, and ornamentation for display, such as fan-shaped crests on dinosaurs. Distinct differences between males and females of a species, called ‘sexual dimorphism’, can also suggest the presence of sexual selection, and features observed in sexually mature adults, where absent from the young, indicate that their purpose might be linked to reproduction.

We can also make inferences from features that are ‘costly’ in terms of how much energy they take to maintain, if we assume that the reproductive advantages outweighed the costs.

Whilst these features might have had multiple uses, the authors conclude that sexual selection should not be ruled out.

“Some scientists argue that many of the elaborate features on dinosaurs were not sexually selected at all,” adds Dr Naish, who is based at the National Oceanography Centre, Southampton.

“But as observations show that sexual selection is the most common process shaping evolutionary traits in modern animals, there is every reason to assume that things were exactly the same in the distant geological past.”

 

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Journal Reference:

  1. Robert J. Knell, Darren Naish, Joseph L. Tomkins, David W.E. Hone. Sexual selection in prehistoric animals: detection and implicationsTrends in Ecology & Evolution, 2013; 28 (1): 38 DOI: 10.1016/j.tree.2012.07.015
University of Southampton (2013, January 29). Survival of the prettiest: Sexual selection can be inferred from the fossil record. ScienceDaily. Retrieved January 30, 2013, from http://www.sciencedaily.com/releases/2013/01/130129080217.htm

Why Are There Redheads? Birds Might Hold the Clues

Jan. 28, 2013 — Red coloration — historically seen as costly in vertebrates — might represent some physiological benefit after all, according to research published in the journal Physiological and Biochemical Zoology.

Barn Swallow, Hirundo rustica, perched on a wire. (Credit: © Eric Isselée / Fotolia)

 

Pheomelanin, which is responsible for red hair and freckles in humans and orange and chestnut coloration in other animals, is known to increase the damage to skin cells and melanoma risk when present in large amounts. Furthermore, its creation involves the consumption of glutathione, a beneficial antioxidant.

In an attempt to unearth the factors favoring the evolution of pheomelanin in spite of its costs, Ismael Galván and Anders P. Møller of the University of Paris-Sud examined the survival from one breeding season to the next of a wild European population of barn swallows, as well as the annual survival rates of 58 species of American birds.

A recent hypothesis claims that the consumption of cysteine (a component of glutathione) that occurs when pheomelanin is produced can be beneficial under conditions of low stress. Cysteine, which is mainly acquired through diet, can be toxic at high levels, so the production of pheomelanin may help to sequester excess quantities of this amino acid.

Galván and Møller measured birds’ blood levels of uric acid and analyzed the coloration of their chestnut throat feathers (an indication of pheomelanin content). When they compared birds that had similar uric acid levels (and therefore similar capacities to excrete excess amino acids), they found that both the European barn swallows and the American birds with larger amounts of pheomelanin in their feathers survived better.

This study is the first to propose that the costs/benefits of pheomelanin may depend on prevailing environmental conditions, and its results suggest that the production of this pigment may even be beneficial in some circumstances. Given that all higher vertebrates, including humans, present pheomelanin in skin, pelage, and plumage, Galván and Møller’s findings increase the scant current knowledge on the physiological consequences of pheomelanin and open new avenues for research that will help us understand the evolution of pigmentation.


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Journal Reference:

  1. Ismael Galván, Anders P. Møller. Pheomelanin-Based Plumage Coloration Predicts Survival Rates in Birds.Physiological and Biochemical Zoology, 2013; : 000 DOI:10.1086/668871
University of Chicago Press Journals (2013, January 28). Why are there redheads? Birds might hold the clues. ScienceDaily. Retrieved January 30, 2013, from http://www.sciencedaily.com/releases/2013/01/130128151930.htm

Neuroscientists Pinpoint Location of Fear Memory in Amygdala

Jan. 27, 2013 — A rustle of undergrowth in the outback: it’s a sound that might make an animal or person stop sharply and be still, in the anticipation of a predator. That “freezing” is part of the fear response, a reaction to a stimulus in the environment and part of the brain’s determination of whether to be afraid of it.

An image showing neurons in the lateral subdivision of the central amygdala (CeL). In red are somatostain-positive (SOM+) neurons, which control fear; in green are another set of neurons known as PKC-delta cells. (Credit: Image courtesy of Bo Li)

 

A neuroscience group at Cold Spring Harbor Laboratory (CSHL) led by Assistant Professor Bo Li Ph.D., together with collaborator Professor Z. Josh Huang Ph.D., have just released the results of a new study that examines the how fear responses are learned, controlled, and memorized. They show that a particular class of neurons in a subdivision of the amygdala plays an active role in these processes.

Locating fear memory in the amygdala

Previous research had indicated that structures inside the amygdalae, a pair of almond-shaped formations that sit deep within the brain and are known to be involved in emotion and reward-based behavior, may be part of the circuit that controls fear learning and memory. In particular, a region called the central amygdala, or CeA, was thought to be a passive relay for the signals relayed within this circuit.

Li’s lab became interested when they observed that neurons in a region of the central amygdala called the lateral subdivision, or CeL, “lit up” in a particular strain of mice while studying this circuit.

“Neuroscientists believed that changes in the strength of the connections onto neurons in the central amygdala must occur for fear memory to be encoded,” Li says, “but nobody had been able to actually show this.”

This led the team to further probe into the role of these neurons in fear responses and furthermore to ask the question: If the central amygdala stores fear memory, how is that memory trace read out and translated into fear responses?

To examine the behavior of mice undergoing a fear test the team first trained them to respond in a Pavlovian manner to an auditory cue. The mice began to “freeze,” a very common fear response, whenever they heard one of the sounds they had been trained to fear.

To study the particular neurons involved, and to understand them in relation to the fear-inducing auditory cue, the CSHL team used a variety of methods. One of these involved delivering a gene that encodes for a light-sensitive protein into the particular neurons Li’s group wanted to look at.

By implanting a very thin fiber-optic cable directly into the area containing the photosensitive neurons, the team was able to shine colored laser light with pinpoint accuracy onto the cells, and in this manner activate them. This is a technique known as optogenetics. Any changes in the behavior of the mice in response to the laser were then monitored.

A subset of neurons in the central amygdala controls fear expression

The ability to probe genetically defined groups of neurons was vital because there are two sets of neurons important in fear-learning and memory processes. The difference between them, the team learned, was in their release of message-carrying neurotransmitters into the spaces called synapses between neurons. In one subset of neurons, neurotransmitter release was enhanced; in another it was diminished. If measurements had been taken across the total cell population in the central amygdala, neurotransmitter levels from these two distinct sets of neurons would have been averaged out, and thus would not have been detected.

Li’s group found that fear conditioning induced experience-dependent changes in the release of neurotransmitters in excitatory synapses that connect with inhibitory neurons — neurons that suppress the activity of other neurons — in the central amygdala. These changes in the strength of neuronal connections are known as synaptic plasticity.

Particularly important in this process, the team discovered, were somatostatin-positive (SOM+) neurons. Somatostatin is a hormone that affects neurotransmitter release. Li and colleagues found that fear-memory formation was impaired when they prevent the activation of SOM+ neurons.

SOM+ neurons are necessary for recall of fear memories, the team also found. Indeed, the activity of these neurons alone proved sufficient to drive fear responses. Thus, instead of being a passive relay for the signals driving fear learning and responses in mice, the team’s work demonstrates that the central amygdala is an active component, and is driven by input from the lateral amygdala, to which it is connected.

“We find that the fear memory in the central amygdala can modify the circuit in a way that translates into action — or what we call the fear response,” explains Li.

In the future Li’s group will try to obtain a better understanding of how these processes may be altered in post-traumatic stress disorder (PTSD) and other disorders involving abnormal fear learning. One important goal is to develop pharmacological interventions for such disorders.

Li says more research is needed, but is hopeful that with the discovery of specific cellular markers and techniques such as optogenetics, a breakthrough can be made.

 

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Journal Reference:

  1. Haohong Li, Mario A Penzo, Hiroki Taniguchi, Charles D Kopec, Z Josh Huang, Bo Li. Experience-dependent modification of a central amygdala fear circuitNature Neuroscience, 2013; DOI: 10.1038/nn.3322
Cold Spring Harbor Laboratory (2013, January 27). Neuroscientists pinpoint location of fear memory in amygdala. ScienceDaily. Retrieved January 30, 2013, from http://www.sciencedaily.com/releases/2013/01/130128104739.htm

Primates, Too, Can Move in Unison

Jan. 28, 2013 — Japanese researchers show for the first time that primates modify their body movements to be in tune with others, just like humans do. Humans unconsciously modify their movements to be in synchrony with their peers. For example, we adapt our pace to walk in step or clap in unison at the end of a concert. This phenomenon is thought to reflect bonding and facilitate human interaction. Researchers from the RIKEN Brain Science Institute report that pairs of macaque monkeys also spontaneously coordinate their movements to reach synchrony.

Monkey training (A), and experimental setting (B and C). (Credit: Image courtesy of RIKEN)

 

This research opens the door to much-needed neurophysiological studies of spontaneous synchronization in monkeys, which could shed light into human behavioral dysfunctions such as those observed in patients with autism spectrum disorders, echopraxia and echolalia — where patients uncontrollably imitate others.

In the research, recently published in the journal Scientific Reports, the team led by Naotaka Fujii developed an experimental set-up to test whether pairs of Japanese macaque monkeys synchronize a simple push-button movement.

Before the experiment, the monkeys were trained to push a button with one hand. In a first experiment the monkeys were paired and placed facing each other and the timing of their push-button movements was recorded. The same experiment was repeated but this time each monkey was shown videos of another monkey pushing a button at varying speeds. And in a last experiment the macaques were not allowed to either see or hear their video-partner.

The results show that the monkeys modified their movements — increased or decreased the speed of their push-button movement — to be in synchrony with their partner, both when the partner was real and on video. The speed of the button pressing movement changed to be in harmonic or sub-harmonic synchrony with the partners’ speed. However, different pairs of monkeys synchronized differently and reached different speeds, and the monkeys synchronized their movements the most when they could both see and hear their partner.

The researchers note that this behavior cannot have been learnt by the monkeys during the experiment, as previous research has shown that it is extremely difficult for monkeys to learn intentional synchronization.

They add: “The reasons why the monkeys showed behavioral synchronization are not clear. It may be a vital aspect of other socially adaptive behavior, important for survival in the wild.”

The study was partly supported by Grant-in-Aid for Scientific Research on Innovative Areas ‘Neural creativity for communication’ (22120522 and 24120720) of MEXT, Japan.

 

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Journal Reference:

  1. Yasuo Nagasaka, Zenas C. Chao, Naomi Hasegawa, Tomonori Notoya, Naotaka Fujii. Spontaneous synchronization of arm motion between Japanese macaquesScientific Reports, 2013; 3 DOI:10.1038/srep01151
RIKEN (2013, January 28). Primates, too, can move in unison. ScienceDaily. Retrieved January 30, 2013, from http://www.sciencedaily.com/releases/2013/01/130128081952.htm

What Holds Chromosomes Together? Structure of DNA-Packaging Proteins Described

Jan. 28, 2013 — To ensure that the genetic material is equally and accurately distributed to the two daughter cells during cell division, the DNA fibers must have an ordered structure and be closely packed. At the Max Planck Institute of Biochemistry in Martinsried near Munich scientists have now elucidated the structure of a ring-shaped protein complex (SMC-kleisin), which ensures order in this packaging process. Together with their cooperation partners at the Korea Advanced Institute of Science and Technology, they studied these proteins in bacteria and found structural analogies to the human complex.

SMC-Kleisin-Complex. (Credit: Image courtesy of Max Planck Institute of Biochemistry)

 

The findings have now been published in the journal Nature Structural & Molecular Biology.

In each cell about two meters of DNA must fit into a cell nucleus that has a diameter of only a few thousandths of a millimeter. There the DNA is organized in individual chromosomes in the form of very long filaments. If they are not equally and accurately distributed to the daughter cells during cell division, this can result in cancer or genetic defects such as trisomy 21. Therefore, to ensure safe transport of DNA during cell division the long and coiled DNA fibers must be tightly packed.

Scientists have only a sketchy understanding of this step. The SMC-kleisin protein complexes play a key role in this process. They consist of two arms (SMC) and a bridge (kleisin). The arms wrap around the DNA like a ring and thus can connect duplicated chromosomes or two distant parts of the same chromosome with each other.

Learning from bacteria Simple organisms like bacteria also use this method of DNA packaging. The scientists, in collaboration with colleagues from South Korea, have now elucidated the structure of a precursor of human SMC-kleisin complexes of the bacterium Bacillus subtilis. The researchers showed that the bacterial SMC-kleisin complex has two arms made of identical SMC proteins that form a ring. The arms differ in their function only through the different ends of the kleisin protein with which they are connected.

In humans the DNA packaging machinery is similarly organized. “We suspect that this asymmetric structure plays an important role in the opening and closing of the ring around the DNA,” explains Frank Bürmann, PhD student in the research group ‘Chromosome Organization and Dynamics’ of Stephan Gruber. In addition, the scientists discovered how the ends of the kleisin can distinguish between correct and wrong binding sites on one pair of arms.

The cohesion of chromosomes is of critical importance for reproduction as well. In human eggs this cohesion must be maintained for decades to ensure error-free meiosis of the egg cell. Failure of cohesion is a likely cause for decreased fertility due to age or the occurrence of genetic defects such as trisomy 21. “The elucidation of the structure of SMC-kleisin protein complexes is an important milestone in understanding the intricate organization of chromosomes,” says group leader Stephan Gruber.

 

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Journal Reference:

  1. Frank Bürmann, Ho-Chul Shin, Jérôme Basquin, Young-Min Soh, Victor Giménez-Oya, Yeon-Gil Kim, Byung-Ha Oh, Stephan Gruber. An asymmetric SMC–kleisin bridge in prokaryotic condensinNature Structural & Molecular Biology, 2013; DOI: 10.1038/nsmb.2488
Max Planck Institute of Biochemistry (2013, January 28). What holds chromosomes together? Structure of DNA-packaging proteins described. ScienceDaily. Retrieved January 30, 2013, from http://www.sciencedaily.com/releases/2013/01/130128081522.htm

Almost 500 New Species Discovered at Senckenberg: Newly Discovered Species in 2011 and 2012

Jan. 25, 2013 — In the last two years scientists at the Senckenberg research institutes have discovered and described almost 500 new species. Taxonomy and scientific collections are among the most important focal points of the Senckenberg Gesellschaft für Naturforschung.


Whether in the deep sea of the Antarctic, in the rainforests of Laos or in domestic, pastoral landscapes — scientists from the ten Senckenberg institutes have discovered new species of plants and animals everywhere. They have even made new discoveries in allegedly familiar research collections — either by studying previously unidentified material or using new research methods. “The objective always is to record and preserve the diversity of life on earth, in other words, biodiversity,” explains Prof. Dr. Dr. h.c. Volker Mosbrugger, Director General of the Senckenberg Gesellschaft für Naturforschung.

491new species from all parts of the globe were described in the last two years by Senckenberg scientists. The extent of new discoveries ranged from colourful island crabs to the Yellow Dyer Rain Frog and fossilised woodpeckers to the first eyeless huntsman spider. Some of the animals have barely been discovered and are already threatened with extinction. “Taxonomy also serves to protect animal species,” explains Dr. Peter Jäger, arachnologist at Senckenberg and himself the discoverer of 46 new spider species in 2011 and 2012. “Only those who know the species variety can develop the necessary protection programmes.” After all, over 100 animal species still die out every day — despite all of the new discoveries.

In 2011 and 2012 Senckenberg researchers discovered 404 living species and 87 fossilised species, of which 416 live on land and 75 in the oceans. Most of the new species (324) come from Asia, while no fewer than 96 species come from Europe. As expected, due to their renowned biodiversity, the arthropods (which include insects, spiders, crabs and myriapods) led the pack of new discoveries with over 300 species, followed by molluscs (64) and plants (30). Both genetic and traditional methods such as morphological examinations were used. “2012 was the most successful Senckenberg year so far, with 331 newly discovered species,” adds Mosbrugger and continues: “We have therefore described around two percent of all newly discovered species worldwide.”

In the last 5 years Senckenberg scientists have discovered over 1,100 new species. Yet the biologists and palaeontologists do not plan to rest on their laurels. “Estimates to date on the global diversity of species differ greatly: experts estimate the number to be between three and 100 million species,” explains Jäger. What is certain is that most of them have never been seen by humans.

There still remains much to do and there are many exciting things yet to be discovered in the field of taxonomy at the Senckenberg institutes.

 

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Senckenberg Research Institute and Natural History Museum (2013, January 25). Almost 500 new species discovered at Senckenberg: Newly discovered species in 2011 and 2012.ScienceDaily. Retrieved January 30, 2013, from http://www.sciencedaily.com/releases/2013/01/130125103929.htm