Liked "Funding for Science - Science" http://ff.im/b8Eia

EvoMRI: Liked "Funding for Science - Science" http://ff.im/b8Eia

See original: Twitter Liked "Funding for Science - Science" http://ff.im/b8Eia

Performing horizontal eye movement exercises can boost your creativity

There have been prior clues that creativity benefits from ample cross-talk between the brain hemispheres. For example, patients who've had a commissurotomy - the severing of the thick bundle of nerve fibres that joins the two hemispheres - show deficits on creative tasks. Now Elizabeth Shobe and colleagues have provided the first evidence that creativity is boosted by an intervention designed to increase hemispheric cross-talk.

Shobe's team tested 62 participants on a version of the "Alternative Uses Test", a divergent thinking challenge that involves dreaming up unconventional uses for everyday objects such as bricks and newspapers.

An important factor that the researchers took note of was the participants' handedness. Prior research has suggested that people who have one hand that is particularly dominant, so-called "strong-handers", have less cross-talk between their brain hemispheres compared with people who are more ambidextrous or "mixed handed".

After an initial attempt at the creativity task, half the participants spent thirty seconds shifting their eyes horizontally back and forth. This exercise is thought to help increase inter-hemispheric communication. The remaining participants acted as controls and just stared straight ahead for 30 seconds.

The key finding is that on their second creativity attempt, strong-handers who'd performed the horizontal eye movements subsequently showed a significant improvement in their creativity, in terms of being more original (i.e. suggesting ideas not proposed by others) and coming up with more categories of use. Staring straight ahead, by contrast, had no effect on creativity.

Another finding was that, overall, the mixed-handed participants performed better on the creativity task than the strong-handers, thus providing further evidence for a link between inter-hemispheric interaction, which mixed-handers have more of, and creativity. But it also turned out that mixed-handers didn't benefit from the horizontal eye movement task. It's as if they already have an optimum amount of hemispheric cross-talk so that the eye movements make no difference. This meant that after the strong-handers had performed the horizontal eye movements, their performance matched that of the mixed-handed participants.

The researchers also showed that, for strong-handers, the beneficial effects of the eye movement exercise lasted nine minutes for originality, but just three to six minutes in terms of coming up with more categories of use.

"Our findings may not apply to more unique populations who are characterised as 'highly creative'," the researchers said, "nor can we conclude ... that the thirty seconds bilateral eye movement task will turn an average individual into an artist, poet, scientist, philosopher, actor or sculptor. However, we certainly do propose that the ... eye movement task will result in a temporary increase in strong-hander's ability to think of creative uses for various house-hold objects."

These new findings complement research published in 2008 showing that horizontal eye movements aid memory performance for strongly-right handed people, but impair the performance of left-handers and mixed-handers.
_________________________________

ResearchBlogging.orgShobe ER, Ross NM, & Fleck JI (2009). Influence of handedness and bilateral eye movements on creativity. Brain and cognition, 71 (3), 204-14 PMID: 19800726

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See original: BPS Research Digest Performing horizontal eye movement exercises can boost your creativity

The Australian's War on Science 41 [Deltoid]

Despite her training in law, Janet Albrechtsen was not able to figure out that the Copenhagen treaty wasn't going to impose a COMMUNIST WORLD GOVERNMENT, so you just know that she has no chance in hell of understanding a scientific question. Albrechtsen claims that it is a "fact" that "Sea levels have remained constant for the past 30 years". Study the graph below from the CSIRO to see that measurements from tide gauges and satellites contradict this claim.

sea level

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See original: ScienceBlogs Select The Australian's War on Science 41 [Deltoid]

Genomarketing!

You've heard of Neuromarketing, which measures the neural activity of consumers (via fMRI or EEG) in response to various products or advertisements. Now, get ready for Genomarketing! The Neuroethics & Law Blog has alerted us to a recent paper by De Neve and Fowler (2009) reporting that people with a specific low efficiency variant of the gene for monoamine oxidase A are significantly more likely to have credit card debt. Monoamine oxidase A (MAO-A) is an enzyme that breaks down the monoamine neurotransmitters (dopamine, norepinephrine, epinephrine, and serotonin). Using data from the National Longitudinal Study of Adolescent Health, the authors found in that sample of 18-26 year olds,Having one or both MAOA alleles of the low efficiency type raises the average likelihood of having credit card debt by 7.8% and 15.9% respectively. About half of [the U.S.] population has one or both MAOA alleles of the low type. Prior research has linked this genetic variation to lack of conscientiousness, impulsivity, and addictive behavior. Is this the foreshadowing of a highly unethical marketing practice? Marketing based on MAO-A genotype, as determined from mailed-in credit card applications and payments? Credit card companies will have in-house labs to extract DNA from stamps and envelope flaps (Sinclair & McKechnie, 2000; Ng et al., 2007).1 Taking it one step further, entire marketing campaigns will be tailored to specific markers in an individual’s genome.2Is this what it’s coming to? Not so fast. Are there any limitations in the findings of De Neve and Fowler (2009)? There are many!! The paper reported:Allele frequency for the low grouping is 41% and high grouping is 59% in our sample. In Wave III, subjects were asked “Do you have any credit card debt?" About 41% answered in the affirmative.However, the ONLY question was asked was “Do you have credit card debt?” – not how much debt or anything else. And of course, the interactions between genes and environment are immense, despite what simplistic popular media notions might lead you to believe (see Neuroanthropology for a critique). Without getting into details (which are better left to other blogs), De Neve and Fowler also note that:Model 2 includes a number of socio-economic factors that influence financial decision-making. Income and education may in fact mediate the relationship between the genes we have identified and credit card usage.Finally, another recent paper (Beaver & Holtfreter, 2009) found that possessing the high efficiency MAO-A allele (opposite of the one discussed here) predicts involvement in fraudulent behaviors. But only if you hang around with the wrong crowd. Specifically,Analysis of male participants from the National Longitudinal Study of Adolescent Health (J. R. Udry, 2003) revealed a statistically significant Gene × Environment interaction in which the high-MAOA activity allele increased the odds of fraudulent behaviors, but only among male participants with a high number of delinquent peers.Fraudulent behavior was determined by two questions. Can you guess them?(1) How many times during the past 12 months have you used someone else’s credit card or bank card without their permission or knowledge?(2) How many times during the past 12 months have you deliberately written a bad check?Ha! Beaver and Holtfreter discuss the contrast of careful and deliberate planning [high-activity alleles] vs. impulsive violence3 [which also has a link to low-activity alleles]:Genetic imaging research examines whether different alleles of a particular polymorphism are associated with differences in brain structure and functioning. Results have revealed that respondents possessing the low-MAOA activity alleles have limbic volume reductions, decreased cingulate activation, and hyperactivity in the amygdala and hippocampus—differences that may begin to explain the link between MAOA and violence. However, the etiologies of serious violence and fraudulent behaviors may be dissimilar. For example, engaging in fraudulent behaviors may take more time and more planning than is typical of most other antisocial behaviors, which are relatively unplanned and impulsive. Bernie Madoff vs. Phil Spector? Sort of.Footnotes1 This would only work, of course, for those who still conduct such business the old fashioned way. And please note that the cited references use these techniques for legitimate purposes!!2 See also Please Complete a Genome Scan with Your Mortgage Application.3 Just stating the obvious here, but having credit card debt in no way, shape, or form implies that one is violent.References...

Beaver, K., & Holtfreter, K. (2009) Biosocial Influences on Fraudulent Behaviors. The Journal of Genetic Psychology, 170(2), 101-114. DOI: 10.3200/GNTP.170.2.101-114  Biosocial Influences on Fraudulent Behaviors


See original: Research Blogging - All Topics - English Genomarketing!

Die Wurst mit Zähnen kriegt keinen Krebs!

In Listen über die merkwürdigsten Tiere auf diesem Planeten taucht eins ziemlich oft ganz weit oben auf: der Nacktmull (Heterocephalus glaber), liebevoll gern auch mal "Penis mit Zähnen" genannt. Schön sieht er ja wirklich nicht aus, doch es sind bekanntlich andere Dinge, die zählen.

Der Nacktmull, wie er leibt und lebt. Quelle: Riude/flickr

Der Nacktmull ist nämlich ein extrem merkwürdiges Tier, und merkwürdig bedeutet für einen Wissenschaftler vor allem eins: interessant! Dieses Nagetier ist beispielsweise das einzige staatenbildende Säugetier. Große Kolonien von bis zu mehreren hundert Tieren leben in selbstgegrabenen unterirdischen Gängen und Höhlen zusammen, die von einer Königin regiert werden. Und ganz ähnlich wie bei Bienen oder Ameisen unterdrückt die Königin die Geschlechtsentwicklung in ihren Untertanen, um die Fortpflanzung in der Kolonie zu kontrollieren.

Nacktmulle sind kaltblütig und empfinden wohl auch keinerlei Schmerz, da ihnen wichtige Moleküle in der Haut fehlen (beispielsweise die sog. Substanz P).

In der letzten Ausgabe der Proceedings of the National Academy of Sciences (PNAS) haben die Forscher Andrei Seluanov, Vera Gorbunova und Kollegen ein weiteres überraschendes Merkmal von Nacktmullen genauer untersucht: Nacktmulle kriegen keinen Krebs! Der Größe nach sind Nacktmulle in etwa mit Mäusen zu vergleichen. Doch während Mäuse und andere gleich große Nager nur wenige Jahre leben, werden Nacktmulle über 30 Jahre alt. Sie scheinen dabei auch nicht "normal" zu altern, sondern sind bis kurz vor ihrem Tod aktiv, pflanzen sich sogar fort. Mäuse kennen ihre natürliche Todesursache (sofern sie nicht vorher gefressen werden) sehr genau; rund 90% der natürlichen Todesfälle bei Mäusen gehen auf Krebs zurück. Und trotz dem sehr viel höheren Alter zum Todeszeitpunkt wurde noch kein Nacktmull mit Krebs gefunden.Das ist natürlich kein sehr überzeugendes Argument - Nacktmulle leben praktisch dauerhaft unterirdisch und sind entsprechend schlecht zu beobachten. Doch ein krebsloses Säugetier weckt verständlicherweise die Phantasie der Forscher, und Seluanov und Kollegen haben nachgesehen, ob auf zellulärer und molekularer Ebene da etwas dran ist.

Und dabei sind sie auf eine interessante Besonderheit gestoßen, die Nacktmullzellen sowohl von Maus-, als auch Menschenzellen unterscheidet: sie mögens nicht so eng. Nimmt man vereinzelte Bindegewebszellen von Mäusen und züchtet sie in Petrischalen mit Wachstumsmedium, dann wachsen sie am Boden und teilen sich munter, bis sie eine gleichmäßige Schicht bilden. Die Zellen hören auf sich zu teilen, sobald sie anfangen müssten, übereinander zu wachsen. Dieses Phänomen nennt man Kontaktinhibition, weil Kontaktsignale zwischen den Zellen die Zellteilung anhalten. Entarten die Zellen aber, dann geht (unter anderem) die Kontaktinhibition verloren, aus der dünnen Zellschicht wird ein wuchernder Haufen. Genauso verhalten sich auch die Bindegewebszellen von Menschen.

Anders die Nacktmulle: Deren Bindegewebszellen hören mit der Zellteilung sehr viel früher auf, lange bevor die Platte dicht genug bewachsen ist, um eine geschlossene Schicht zu bilden. Dies wurde von den Forschern early contact inhibition genannt, um sie von der normalen Kontaktinhibition zu unterscheiden.Jetzt könnte man meinen, bei den Nacktmullen sei einfach nur ein Regler verstellt, die maximale Zelldichte für den Teilungsstopp. Doch eine der Zelllinien der Forscher verlor nach mehreren Monaten in Kultur diese frühe Inhibition und begann sich wieder zu teilen. Allerdings nur, bis die Platte mit einer geschlossenen Zellschicht bewachsen war. Nacktmulle besitzen also zwei gestaffelte Sperren gegen unkontrollierte Zellteilung!

Die Frage war: was in der Zelle macht den Unterschied? Zwei der wichtigsten Regler des Zellwachstum sind die Proteine p53 und pRb (die deswegen auch sehr häufig bei Krebs mutiert sind). Beide sind in die Entscheidungswege in der Zelle involviert, den Zellzyklus entweder anzuhalten, oder die Zelle gleich ganz in den programmierten Zelltod Apoptose zu treiben. Und es mussten auch beide Proteine deaktiviert werden, um die frühe Kontaktinhibition der Nacktmullzellen zu umgehen. Genauer gesagt wachsen die Zellen zwar schon weiter, wenn p53 oder pRb ausfällt, sterben aber aufgrund der Apoptose ab. Erst wenn beide Proteine fehlen, kann man das Wachstum durch das Ausbleiben der Apoptose sehen.

Die Kontaktinhibition bei Mensch und Maus wird zudem reguliert durch das Protein p27, dessen Menge in der Zelle mit zunehmender Zelldichte auch größer wird. Die Kontaktinhibition kommt dadurch zustande, dass p27 die Inaktivierung von pRb verhindert und der Zellzyklus so angehalten wird. Und genauso ist es auch bei den Zellen von Nacktmullen, allerdings nur bei der "normalen" Kontaktinhibition. Die frühe Abwehr, die man nur bei den Nacktmullen findet, ist allerdings nicht durch p27 kontrolliert.

Ein zweites, p27 ähnliches Protein namens p16 ist bei Mensch und Maus bisher nicht sehr gut verstanden. Es hat jedoch auch eine, allerdings wenig wichtige, Rolle in der Kontaktinhibition neben p27. Seluanov und Kollegen konnten nun zeigen, dass sich im Nacktmull die Funktionen von p27 und p16 zeitlich voneinander getrennt haben, p16 ist nämlich der Regulator der frühen Kontaktinhibition.

Die Signalwege in der Zelle, die Zellwachstum und Apoptose regulieren. Die Proteine, deren Namen in diesem Artikel gefallen sind, finden sich rechts unten in der Abbildung. Bild anklicken für eine größere Version. [1] Quelle: Roadnottaken/Wikipedia

Die Frage ist jetzt, wie man diese Beobachtungen einordnen kann. Krebs entsteht nicht einfach, wenn die Kontaktinhibition ausfällt. Jedenfalls nicht nur. Es müssen verschiedene Proteine in Zellteilung, Apoptose, Telomerstoffwechsel etc. mutieren, dass aus normalen Krebszellen werden. Demzufolge wäre es sehr unwahrscheinlich, wenn die frühe Kontaktinhibition der einzige Unterschied von Nacktmullzellen wäre, um sich vor der Krebsentstehung zu schützen. Die molekularen Beweise in diesem Paper zeigen aber, dass die Berichte über die krebslosen Nager begründet sind, und ermutigen auch die weitere Erforschung des Nacktmulls als Modell für die Krebsforschung.

[1] So kompliziert es hier auch aussieht, die Informationen sind teilweise schon wieder überholt. Ich will hier niemanden mit einer komplizierten Abbildung beeindrucken, aber wirklich gute Abbildungen zu dem Thema gibt es nicht, jedenfalls nicht frei zugänglich. Die Abbildung soll aber auch deutlich machen, dass das einfache Bild, das von mir hier, aber auch von den Autoren im Paper, gezeichnet wurde, der Komplexität in der Zelle nicht wirklich gerecht wird.

Seluanov, A., Hine, C., Azpurua, J., Feigenson, M., Bozzella, M., Mao, Z., Catania, K., & Gorbunova, V. (2009). Hypersensitivity to contact inhibition provides a clue to cancer resistance of naked mole-rat Proceeding...

Seluanov, A., Hine, C., Azpurua, J., Feigenson, M., Bozzella, M., Mao, Z., Catania, K., & Gorbunova, V. (2009) Hypersensitivity to contact inhibition provides a clue to cancer resistance of naked mole-rat. Proceedings of the National Academy of Sciences. DOI: 10.1073/pnas.0905252106  Hypersensitivity to contact inhibition provides a clue to cancer resistance of naked mole-rat


See original: Research Blogging - All Topics - German Die Wurst mit Zähnen kriegt keinen Krebs!

Governance and Economy

The fall of the Berlin wall was a monumental event in history. Interestingly enough it acted as the end of a large-scale governance/economic experiment. Here we have two societies, each with similar backgrounds, but each with drastically different views of government and economics. On one side was placed a highly controlled society and on the [...]

See original: Steady State Blog Governance and Economy

'Is plant diversity beautiful?' study asks

A new study addresses a simple but seldomly asked question: "Is plant diversity beautiful?"Researchers set out to answer this by asking study participants to rate the attractiveness of different meadow plots with varying levels of species richness...read more...

Lindemann-Matthies, P., Junge, X., & Matthies, D. (2009) The influence of plant diversity on people’s perception and aesthetic appreciation of grassland vegetation. Biological Conservation. DOI: 10.1016/j.biocon.2009.10.003  The influence of plant diversity on people’s perception and aesthetic appreciation of grassland vegetation


See original: Research Blogging - All Topics - English 'Is plant diversity beautiful?' study asks

Unitary mindfulness in collective action [Gene Expression]

In reviewing a paper which sketches out the boundary conditions under which group-level natural selection would result in the emergence of altruism as a genetically encoded trait, I stated:

... I would look to cultural group selection, because there are many cases of women being assimilated into a dominant culture, and their offspring speaking the language, and expressing the values, in totality of their fathers. One inherits 50% of one's genes from one's mother and one's father, but inheritance of cultural traits which are distinctive between parents may show very strong biases. Partitioning variance between and within groups on cultural traits often shows far greater between group differences; consider variance in speech, within a tribe there are slight variations, but between tribes the accent variation may be strong enough to accurately assign any individual to the correct tribe by speech alone.

Additionally, in the comments Jason Malloy observes:

Altruistic people are cooperative, and being cooperative can lead to more children in a social species for a variety of reasons (e.g., religious people have more children and donate more to charity in the modern US).

Altruism is best understood in terms of individual differences within a population and evolutionary stable strategies. Clearly individuals differ in their pro-social tendencies, and the relative frequency of pro-social people within a population can shift given different conditions. I'm sure there are some environments where it's reproductively advantageous for 90% of people to be sociopaths.

As I noted the biggest problem for biological group selection is that groups are clumsy & lumbering organisms in an evolutionary sense. They don't reproduce fast, and may not exhibit enough distinctiveness to become a coherent unit of selection. Multicellular organisms face the problem of being slow to respond to evolutionary pressures in relation to their pathogens, ergo, sex. The nature of sexual process is also essential in mediating intragenomic competition and conflicts, the details of which serve as the core of Mark Ridley's book The Cooperative Gene.

Shifting the focus to human social entities, anyone who has worked in a large corporation can tell plenty of stories of how organizations fragment in interests on the level of subsidiaries, working groups and individuals. Nevertheless, corporations have become very common, and firms are able to coordinate collective action so as to flourish and succeed, at least for a time (like organisms, it does seem to me that firms grow, mature and eventually decline due to institutional sclerosis).

A recent paper in PNAS outlines the formal and empirical case for why group-level selection as a biological phenomenon for humans is likely far rarer than as a cultural dynamic. Culture rather than genes provides greater scope for the evolution of large-scale human prosociality:

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See original: ScienceBlogs Select Unitary mindfulness in collective action [Gene Expression]

The Detox Delusion: Kudos to Duke Integrative Medicine Nutritionist [Terra Sigillata]

Yesterday, the real-life mailbox brought the Pharmboy household the Fall 2009 issue of DukeMedicine connect, a biannual publication on current news from the Duke University Health System. Produced by DUHS Marketing and Creative Services, it "strives to offer current news about health topics of interest" to its readers. This issue is not yet online but you can see the Spring 2009 issue here.

What caught my eye was a cover teaser titled "Detox Delusion" and an article on detoxification diets focusing on an interview with Beth Reardon a nutritionist with Duke Integrative Medicine.(The articles sadly don't have bylines so I can only give credit to the editor, Kathleen Yount.)

The article focuses on the fallacy of detoxification diets, extreme and sometimes dangerous regimens of purges, enemas, supplements, herbs, with the misguided goal of clearing one's body of "toxins." These amorphous toxins are never named, much less denoted with an IUPAC chemical name, but prey upon the fears of our "chemical" environment.

The article refers to the current "Master Cleanse" craze, known also as the Lemon Cleanse or Maple Syrup Diet. Not mentioned in the article is that the diet was developed in 1941 by an unlicensed practitioner named Stanley Burroughs and popularized most recently in the 2005 Peter Glickman book, Lose Weight, Have More Energy and Be Happier in 10 Days and his MasterCleanse/Raw Food website.

So, I was very pleased to see this:

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See original: ScienceBlogs Select The Detox Delusion: Kudos to Duke Integrative Medicine Nutritionist [Terra Sigillata]

I’m so tired of coping: Self regulation, executive functions and chronic pain

Changes take energy – that’s nothing new, I know, but perhaps something as clinicians we might forget when we work with people who have chronic pain. I was thinking about this as I’ve had a week away from regular blogging so I could focus on writing and some self care.  Things are busy and [...]...

Solberg Nes, L., Roach, A., & Segerstrom, S. (2009) Executive Functions, Self-Regulation, and Chronic Pain: A Review. Annals of Behavioral Medicine, 37(2), 173-183. DOI: 10.1007/s12160-009-9096-5  Executive Functions, Self-Regulation, and Chronic Pain: A Review


See original: Research Blogging - All Topics - English I’m so tired of coping: Self regulation, executive functions and chronic pain

Performing horizontal eye movement exercises can boost your creativity

There have been prior clues that creativity benefits from ample cross-talk between the brain hemispheres. For example, patients who've had a commissurotomy - the severing of the thick bundle of nerve fibres that joins the two hemispheres - show deficits on creative tasks. Now Elizabeth Shobe and colleagues have provided the first evidence that creativity is boosted by an intervention designed to increase hemispheric cross-talk.Shobe's team tested 62 participants on a version of the "Alternative Uses Test", a divergent thinking challenge that involves dreaming up unconventional uses for everyday objects such as bricks and newspapers.An important factor that the researchers took note of was the participants' handedness. Prior research has suggested that people who have one hand that is particularly dominant, so-called "strong-handers", have less cross-talk between their brain hemispheres compared with people who are more ambidextrous or "mixed handed".After an initial attempt at the creativity task, half the participants spent thirty seconds shifting their eyes horizontally back and forth. This exercise is thought to help increase inter-hemispheric communication. The remaining participants acted as controls and just stared straight ahead for 30 seconds.The key finding is that on their second creativity attempt, strong-handers who'd performed the horizontal eye movements subsequently showed a significant improvement in their creativity, in terms of being more original (i.e. suggesting ideas not proposed by others) and coming up with more categories of use. Staring straight ahead, by contrast, had no effect on creativity. Another finding was that, overall, the mixed-handed participants performed better on the creativity task than the strong-handers, thus providing further evidence for a link between inter-hemispheric interaction, which mixed-handers have more of, and creativity. But it also turned out that mixed-handers didn't benefit from the horizontal eye movement task. It's as if they already have an optimum amount of hemispheric cross-talk so that the eye movements make no difference. This meant that after the strong-handers had performed the horizontal eye movements, their performance matched that of the mixed-handed participants.The researchers also showed that, for strong-handers, the beneficial effects of the eye movement exercise lasted nine minutes for originality, but just three to six minutes in terms of coming up with more categories of use. "Our findings may not apply to more unique populations who are characterised as 'highly creative'," the researchers said, "nor can we conclude ... that the thirty seconds bilateral eye movement task will turn an average individual into an artist, poet, scientist, philosopher, actor or sculptor. However, we certainly do propose that the ... eye movement task will result in a temporary increase in strong-hander's ability to think of creative uses for various house-hold objects."These new findings complement research published in 2008 showing that horizontal eye movements aid memory performance for strongly-right handed people, but impair the performance of left-handers and mixed-handers._________________________________Shobe ER, Ross NM, & Fleck JI (2009). Influence of handedness and bilateral eye movements on creativity. Brain and cognition, 71 (3), 204-14 PMID: 19800726...

Shobe ER, Ross NM, & Fleck JI. (2009) Influence of handedness and bilateral eye movements on creativity. Brain and cognition, 71(3), 204-14. PMID: 19800726   Influence of handedness and bilateral eye movements on creativity.


See original: Research Blogging - All Topics - English Performing horizontal eye movement exercises can boost your creativity

Amphibian Skin

I decided to take a break from bacteria today and decided it might be fun to just choose something totally random to write about. Taking a daring leap into the unknown I decided not only to try and find out somthing about multicellular creatures, but about those multicellular creatures about which I know the least: amphibians.The above picture of an axelotl may have had something to do with my decision. Note the similarity to a pokemon that has accidently wandered into Star Wars.There are three main orders of amphibians; salamanders and newts, toads and frogs, and caecilians; the blind legless ones that live at the bottom of caves. They are cold blooded and, unlike many other multicellulared animals, they don't regard the outside environment as completely seperated from the inner. They can exchange both water and oxygen through their skin, in fact some salamanders exchange all of their oxygen in this way, and thus don't have any gils or lungs at all.Skin is therefore a very exceptional organ in salamanders, as it is used for fluid balance, respiration and the transport of essential ions, as well as the more traditional uses of protection and sensing. Possibly because of this, it has it's own protection system against infection. Amphibians have both an adaptive and innate immune system, but in addition to this they have granular glands under the dermis layer of the skin that release antimicrobial peptides in response to stress. Peptide release is stimulated by the adrenergic receptors, so any circumstance of shock of pressure results in an extra layer of protective peptides over the skin surface. They are quite potent as well, providing potential protection from bacteria, fungi, protazoa and even viruses.As cold-blooded creatures have a slower reacting immune system, this quick, automatic and generic response to stressful conditions provides important protection for the skin, which is vital for maintaining internal homeostasis. And as well as peptide-releasng glands, they also have pigment granules under the skin, which give them bright colours and mean they can change between colours depending on environmental conditions or what they want to communicate. Amphibians have such beautiful colours...why do they always make dinosaurs blotchy khaki!There is however a downside to using your skin to take things up from the environment. Water isn't the only thing that gets through permeable skin, chemicals dissolved in the water can as well, which can be fatal if the chemical in question is a herbicide such as atrazine or glyphosate. Chemical contamination may be one reason (and there are, no doubt, many others) for the dramatic decline in the number of amphibians over recent years. Apparently conservationists are majorly concerned about this.And they don't seem to get as much press as endangered mammals either. Which is a pity because that axelotl does look quite sweet. And amphibians are the only living proof we have left to remind us that the dinosaurs could have had bright-coloured polkadots:Imagine those colours....on a velociraptor!---Rollins-Smith, L. (2005). Antimicrobial Peptide Defenses in Amphibian Skin Integrative and Comparative Biology, 45 (1), 137-142 DOI: 10.1093/icb/45.1.137Quaranta A, Bellantuono V, Cassano G, & Lippe C (2009). Why amphibians are more sensitive than mammals to xenobiotics. PloS one, 4 (11) PMID: 19888346...

Rollins-Smith, L. (2005) Antimicrobial Peptide Defenses in Amphibian Skin. Integrative and Comparative Biology, 45(1), 137-142. DOI: 10.1093/icb/45.1.137  Antimicrobial Peptide Defenses in Amphibian Skin

Quaranta A, Bellantuono V, Cassano G, & Lippe C. (2009) Why amphibians are more sensitive than mammals to xenobiotics. PloS one, 4(11). PMID: 19888346   Why amphibians are more sensitive than mammals to xenobiotics.


See original: Research Blogging - All Topics - English Amphibian Skin

Ausstellung: Im Phyletischen Museum geht es um Kieselalgen und ihren Formenreichtum

Mit bloßem Auge kaum sichtbar, sind sie Inspiration für Kunst und Wissenschaft die Kieselalgen. Kieselalgen kommen im Alltag beispielsweise in Katzenstreu vor. Eine Sonderschau im Phyletischen Museum zeigt ab Freitag, wie die Natur als Vorbild für Kunst- und Alltagsgegenstände dient. Konzipiert haben die Ausstellung Studenten der Bauhaus-Universität Weimar.
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See original: Uploads by StadtderWissenschaft Ausstellung: Im Phyletischen Museum geht es um Kieselalgen und ihren Formenreichtum

Freethinker Sunday Sermonette: more religion and child abuse [Effect Measure]

Richard Dawkins has taken a lot of abuse himself for having the temerity to suggest that some kinds of religious upbringings can be considered abusive even if no physical harm is involved. We know that Catholic children suffered abuse at the hands of priests and nuns, and that some fundamentalist Christians have also engaged in extremely abusive practices. We don't usually think of Jews as routinely engaging in this, but there is something non-sectarian about the fundamentalist mindset. You could do a 'global search and replace' and this sad tale of escape from orthodox Judaism could be interchanged with those of many evangelical Christian or Muslim sects. I have no trouble calling this institutionalized child abuse:

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See original: ScienceBlogs Select Freethinker Sunday Sermonette: more religion and child abuse [Effect Measure]