Music from the Universe

El ‘baile’ de una célula del oído “al compás del reloj”

noreply@blogger.com (Unknown) — Fri, 28 Dec 2018 14:54:00 +0000

En el siguiente video se puede apreciar como una célula ciliada externa* del oído responde al ser expuesta a la canción “Al compás del reloj”:

* El oído humano en su parte más interna consta de dos tipos de células sensibles al sonido: las células ciliadas internas y las externas. Las internas detectan las ondas sonoras y las transforma en señales eléctricas para que viajen por el nervio auditivo hasta el cerebro donde son interpretadas como sonido. Las externas actúan como un controlador del volumen, es decir como un amplificador de la señal.

En el Universo todo se mueve y con ritmo

noreply@blogger.com (Unknown) — Wed, 14 Mar 2018 21:23:00 +0000

Crédito de la imagen: Rhys Taylor of http://www.rhysy.net/

Sobre la superficie de la Tierra tenemos el movimiento de traslación de esta alrededor del Sol, que es de unos 108.000 kilómetros por hora, y el de rotación, que puede ser de hasta 1.700 kilómetros por hora en el ecuador.

Y al igual que los planetas giran alrededor del Sol, este gira en torno al núcleo de nuestra galaxia.

El Sol gira alrededor del núcleo de la Vía Láctea a unos 792.000 kilómetros por hora y a pesar de esa aparentemente descomunal velocidad tarda unos 225 millones de años en completar una órbita.

La misma Vía Láctea, y con ella el Sol, se mueve a unos 2,1 millones de kilómetros por hora más o menos en dirección al cúmulo de Leo y de Virgo.

Veery thrush songbird of North America singing with swing / El pájaro tordo (mirlo) Veery de los Estados Unidos, cantando con swing

noreply@blogger.com (Unknown) — Wed, 16 Aug 2017 16:04:00 +0000

In the following audio clips you can hear how the veery swings in the same way that human musicians do / En los siguientes audios pueden escuchar al Veery cantando a la manera que lo hace un músico humano.

Here’s the veery at normal speed / Este es su canto a velocidad normal:

When the veery’s song is slowed down you can spot how it swings / Cuando el canto es disminuido en su velocidad se puede apreciar cómo es que el Veery canta con swing:

Es interesante notar cómo esta ave logra mantener el ritmo y la entonación en cada repetición.... definitivamente son aves con muy buen oído, muy afinadas y con pulso de reloj.

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Nuestros miles de relojes corporales / Our thousands of body clocks

noreply@blogger.com (Unknown) — Sat, 05 Aug 2017 00:01:00 +0000

Nuestro cuerpo tiene miles de relojes (no solo el que está en el cerebro) que orquestan cuidadosamente el funcionamiento de nuestros tejidos y órganos, desde el corazón, los pulmones hasta el hígado.

Estos relojes no sólo nos sirven para comer regularmente, sino también conlleva a que las diferentes partes del cuerpo se sintonicen para trabajar de manera óptima en determinados momentos del día. Cuando estos relojes se desincronizan puede traer consecuencias graves. Por el contrario, es necesario aprender a aprovechar estos ritmos.

By Allison Aubrey

March 10, 2015

We've long known about the master clock in our brains that helps us maintain a 24-hour sleep-wake cycle.

But in recent years, scientists have made a cool discovery: We have different clocks in virtually every organ of our bodies — from our pancreas to our stomach to our fat cells.

"Yes, there are clocks in all the cells of your body," explains Fred Turek, a circadian scientist at Northwestern University. "It was a discovery that surprised many of us."

We humans are time-keeping machines. And it seems we need regular sleeping and eating schedules to keep all of our clocks in sync.

Studies show that if we mess with the body's natural sleep-wake cycle — say, by working an overnight shift, taking a transatlantic flight or staying up all night with a new baby or puppy — we pay the price.

Our blood pressure goes up, hunger hormones get thrown off and blood sugar control goes south.

We can all recover from an occasional all-nighter, an episode of jet lag or short-term disruptions.

But over time, if living against the clock becomes a way of life, this may set the stage for weight gain and metabolic diseases such as Type 2 diabetes.

"What happens is that you get a total de-synchronization of the clocks within us," Turek says, "which may be underlying the chronic diseases we face in our society today."

So consider what happens, for instance, if we eat late or in the middle of the night. The master clock — which is set by the light-dark cycle — is cuing all other clocks in the body that it's night. Time to rest.

"The clock in the brain is sending signals saying: Do not eat, do not eat!" says Turek.

But when we override this signal and eat anyway, the clock in the pancreas, for instance, has to start releasing insulin to deal with the meal. And, research suggests, this late-night munching may start to reset the clock in the organ. The result? Competing time cues.

"The pancreas is listening to signals related to food intake. But that's out of sync with what the brain is telling it to do," says Turek. "So if we're sending signals to those organs at the wrong time of day — such as eating at the wrong time of day — [we're] upsetting the balance."

And there's accumulating evidence that we may be more sensitive to these timing cues than scientists ever imagined.

Consider, for instance, the results of a weight-loss study that we reported on, which was published in the International Journal of Obesity. Researchers found that the timing of meals can influence how much weight people lose.

"The finding that we had was that people who ate their main meal earlier in the day were much more successful at losing weight," says study author Frank Scheer, a Harvard neuroscientist who directs the Medical Chronobiology Program at Brigham and Women's Hospital.

In fact, early eaters lost 25 percent more weight than later eaters — "a surprisingly large difference," Scheer says. Another study found that eating a big breakfast was more conducive to weight loss, compared with a big dinner — adding to the evidence that the timing of meals is important.

Beyond weight management, there's evidence that the clocks in our bodies — and the timing of our sleeping, eating and activities — play multiple roles in helping us maintain good health. And different systems in the body are programmed to do different tasks at different times.

For instance, doctors have long known that the time of day you take a drug can influence its potency. "If you take a drug at one time of day, it might be much more toxic than another time of day," Turek says. Part of this effect could be that the liver is better at detoxifying at certain times of day.

Turek says his hope is that, down the road, circadian science will be integrated into the practice of medicine.

"We'd like to be in a position where we'd be able to monitor hundreds of different rhythms in your body and see if they're out of sync — and then try to normalize them," Turek says.

Whether — or how quickly — this may happen is hard to say. But what's clear is that the study of the biology of time is exploding.

"What we're doing now in medicine is what Einstein did for physics," says Turek. "He brought time to physics. We're bringing time to biology."

The irony, of course, is that this insight comes at a time when the demands of our 24/7 society mean more and more of us are overriding our internal clocks.

Fuente: http://www.npr.org/sections/thesalt/2015/03/10/389596946/circadian-surprise-how-our-body-clocks-help-shape-our-waistlines

Un reloj maestro que también controla nuestra temperatura corporal

noreply@blogger.com (Unknown) — Wed, 26 Jul 2017 16:33:00 +0000

El área del cerebro conocida como el núcleo supraquiasmático (SCN por su siglas en inglés) es el reloj maestro del cuerpo. Utiliza la luz para sincronizar los ritmos del cuerpo con la noche y el día. Controla directamente los ciclos de sueño / vigilia pero indirectamente controla otros procesos, como el hambre y la sed, y lo hace mediante el control del termostato del cuerpo, el área preóptica del cerebro.

A clump of just a few thousand brain cells, no bigger than a mustard seed, controls the daily ebb and flow of most bodily processes in mammals — sleep/wake cycles, most notably. Now, Johns Hopkins scientists report direct evidence in mice for how those cell clusters control sleep and relay light cues about night and day throughout the body.

A summary of their study of the brain region known as the suprachiasmatic nucleus, or SCN, will be published online in the journal Current Biology on Dec. 22.

“Light has a strong, negative and direct effect on sleep in humans. We experience this every evening when we turn out the lights before we go to bed and every morning when we open the curtains to let light in. However, very little was known about how this happens. Learning that the SCN is indeed required for light to directly regulate sleep is an important piece of the circadian rhythm puzzle,” says Seth Blackshaw, Ph.D., professor of neuroscience at the Johns Hopkins University School of Medicine. “Our chances of finding treatments for people with sleep disorders, or just jet lag, improve the more we understand the details about how sleep is controlled.”

Blackshaw says scientists have known for a while that the SCN functions as a master clock to synchronize sleep and other so-called circadian rhythms in humans and other mammals. But its importance in the more immediate regulation of sleep, like when a bright light wakes someone up, remained debatable because the experiments needed to show its role in a living animal were essentially impossible. “If you surgically removed the SCN in mice, their sleeping and waking were no longer immediately influenced by light, but you can’t remove the SCN without also severing the optic nerve that brings light information to it from the retina. So no one knew if this resistance to light was due to the missing SCN or the missing optic nerve,” says Blackshaw.

In experiments first reported several years ago, Blackshaw’s team found a way to disrupt the normal function of the SCN without physically removing it and damaging the optic nerve. The researchers were trying to identify genes involved in the development of the mouse hypothalamus, the area of the brain that includes the SCN. They identified one such gene, dubbed LHX1, that seemed to be the earliest to “turn on” in the development of the fetal SCN.

For the new round of experiments, the scientists used a customized genetic tool to delete LHX1 just from cells that make up the SCN. They found that the mice experienced severely disrupted circadian rhythms, although they could still be weakly synchronized to light cycles. And the cells of the SCN no longer produced six small signaling proteins known to coordinate and reinforce their efforts, a biochemical process known as coupling.

Whether the mice were kept in constant light, constant darkness or normal cycles of both, their sleep times and duration became random. Cumulatively, they slept for the same amount of time, about 12 hours each 24-hour period, like normal mice, but there was no pattern to the cycle.

“This experiment showed that the SCN is critical to light’s immediate effect on sleep,” says Blackshaw.

The scientists also noticed that in the SCN-impaired mice, core body temperatures didn’t cycle normally. The average body temperature for humans is 37 degrees Celsius, but it fluctuates throughout the day by about 1 degree Celsius, being highest in the afternoon and lowest just before dawn. A similar pattern occurs in mice. These small temperature fluctuations can have a big influence on processes that occur outside the brain that are also under circadian control, such as glucose usage and fat storage, and it has been speculated that they may be the main way by which the SCN controls these bodily rhythms.

In contrast, one of the hallmarks of the body’s circadian processes, including cycles in core body temperature, is that they aren’t generally disturbed by large temperature changes. “Otherwise, you would feel jet-lagged every time you got a fever,” says Blackshaw. But it wasn’t clear from mouse experiments if the SCN was responsible for this resistance to strong temperature changes in living animals. Normal SCN cells in the lab keep cycling in synchrony without regard to temperature pulses, but research from another group showed that they could be “reset” by temperature changes if they could no longer signal to each other.

Knowing that the SCN cells in their LHX1-deficient mice were similarly impaired, a graduate student in Blackshaw’s lab, Joseph Bedont, reasoned that their mice might now be able to return to normal temperature cycles if given pulses of heat.

To try that, they injected the mice — kept in the dark — with a molecule found in bacterial cell walls, which makes them run a fever in response to the perceived threat. Fever is a first-line infection fighter in humans as well. As suspected, their regular core temperature cycling came back.

“These results suggest that the SCN is indeed responsible for the temperature resistance of circadian rhythms in live animals, and it shows us how important SCN coupling is,” says Blackshaw. “It also bolsters the idea that the body’s other physiologic cycles, such as hunger and hormone secretion, are synchronized by the SCN through its regulation of core body temperature.”

Additional experiments identified several molecules that may be directing these vital signals. The Blackshaw team plans to follow up by studying each one to determine their roles. With that information, drug developers will have a better idea which component to target and how. To treat jet lag, for example, Blackshaw says that one hypothetical option would be to briefly block LHX1 so that the SCN cells uncouple and become easier to reset, either by light or temperature. But no one knows yet if that plan would produce undesirable side effects or the desired outcomes.

Fuente: http://neurosciencenews.com/fever-jet-lag-5798/

El rítmico y simétrico Hexágono de Saturno

noreply@blogger.com (Unknown) — Tue, 07 Mar 2017 20:48:00 +0000

El Hexágono que se aprecia en el polo norte de Saturno, rota alrededor de su centro a casi exactamente el mismo ratio en que el mismo planeta rota sobre su eje.

Your Rhythmic Brain

noreply@blogger.com (Unknown) — Tue, 21 Feb 2017 17:53:00 +0000

A través de células madre han podido extraer cómo es que las neuronas funcionan de manera rítmica.

Recently, neuroscientists at the Salk Institute used stem cells to generate diverse networks of self-contained spinal cord systems in a dish, dubbed circuitoids, to study this rhythmic pattern in neurons. The work, which appears online in the February 14, 2017, issue of eLife, reveals that some of the circuitoids–with no external prompting–exhibited spontaneous, coordinated rhythmic activity of the kind known to drive repetitive movements.

“It’s still very difficult to contemplate how large groups of neurons with literally billions if not trillions of connections take information and process it,” says the work’s senior author, Salk Professor Samuel Pfaff, who is also a Howard Hughes Medical Institute investigator and holds the Benjamin H. Lewis Chair. “But we think that developing this kind of simple circuitry in a dish will allow us to extract some of the principles of how real brain circuits operate. With that basic information maybe we can begin to understand how things go awry in disease.”

Nerve cells in your brain and spinal cord connect to one another much like electronic circuits. And just as electronic circuits consist of many components, the nervous system contains a dizzying array of neurons, often resulting in networks with many hundreds of thousands of cells. To model these complex neural circuits, the Pfaff lab prompted embryonic stem cells from mice to grow into clusters of spinal cord neurons, which they named circuitoids. Each circuitoid typically contained 50,000 cells in clumps just large enough to see with the naked eye, and with different ratios of neuronal subtypes.

With molecular tools, the researchers tagged four key subtypes of both excitatory (promoting an electrical signal) and inhibitory (stopping an electrical signal) neurons vital to movement, called V1, V2a, V3 and motor neurons. Observing the cells in the circuitoids in real time using high-tech microscopy, the team discovered that circuitoids composed only of V2a or V3 excitatory neurons or excitatory motor neurons (which control muscles) spontaneously fired rhythmically, but that circuitoids comprising only inhibitory neurons did not. Interestingly, adding inhibitory neurons to V3 excitatory circuitoids sped up the firing rate, while adding them to motor circuitoids caused the neurons to form sub-networks, smaller independent circuits of neural activity within a circuitoid.

“These results suggest that varying the ratios of excitatory to inhibitory neurons within networks may be a way that real brains create complex but flexible circuits to govern rhythmic activity,” says Pfaff. “Circuitoids can reveal the foundation for complex neural controls that lead to much more elaborate types of behaviors as we move through our world in a seamless kind of way.”

Because these circuitoids contain neurons that are actively functioning as an interconnected network to produce patterned firing, Pfaff believes that they will more closely model a normal aspect of the brain than other kinds of cell culture systems. Aside from more accurately studying disease processes that affect circuitry, the new technique also suggests a mechanism by which dysfunctional brain activity could be treated by altering the ratios of cell types in circuits.

Fuente: http://neurosciencenews.com/rhythm-parkinsons-6114/

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El baile y canto de las aves

noreply@blogger.com (Unknown) — Thu, 16 Feb 2017 21:03:00 +0000

En el siguiente video se puede apreciar, en cámara lenta, cómo el ritmo y la música están muy presentes en el mundo animal, aunque muchas veces no lo notemos.

Según los investigadores que capturaron esta peculiar forma de cortejo en una pareja de pájaros cantores, los pasos parecían estar sincronizados con la canción.

Lobos que cantan

noreply@blogger.com (Unknown) — Mon, 19 Dec 2016 23:25:00 +0000

Nature is musical for those who knows how to listen to it.
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La naturaleza es musical para aquellos que saben escucharla.

Here is another video / Aquí otro video:

https://www.facebook.com/nywolforg/videos/10154081315462635/?hc_ref=NEWSFEED

Danza Celestial: las lunas de Jupiter

noreply@blogger.com (Unknown) — Mon, 19 Dec 2016 23:09:00 +0000

En este video de la NASA se puede apreciar por primera vez en la historia, y captado por la sonda Juno durante el mes de junio del 2016, cómo se da el movimiento las lunas Io, Europa, Ganimedes y Callisto, orbitando alrededor de Júpiter. Este video muestra pues la armonía del Universo, en movimiento !!!

La Música del Cerebro

noreply@blogger.com (Unknown) — Thu, 10 Mar 2016 21:45:00 +0000

Por María Arce

El cerebro suena como un piano a puro jazz. Con acordes y escalas típicos de una improvisación de jazz. Así lo demuestra un experimento realizado por científicos de la Universidad de Ciencia Electrónica y Tecnología en China que lograron transformar la actividad neurológica del cerebro en una melodía.

"La música y el lenguaje nos definen como humanos. La expresión emocional y la comunicación, a través del lenguaje y la expresión artística no lingüística, se reconocen fuertemente vinculadas a la salud y al bienestar. Por lo tanto, como una expresión artística, la música puede representar la mente humana o el estado de ánimo". Con esa premisa en mente, publicada en la revista especializada PLoS ONE, los científicos chinos decidieron poner manos a la obra y ampliar trabajos del pasado que habían intentado traducir las ondas cerebrales a melodías.

Durante las últimas décadas, científicos y artistas buscaron diferentes métodos para hacer de un electroencefalograma (EEG) una partitura, pero los resultados habían sido bastante toscos, con melodías chillonas y metálicas y en algunos casos insoportables. Hasta ahora.

Los científicos chinos lograron que el cerebro ‘cante’ luego de combinar los impulsos eléctricos que emite cuando piensa con el flujo sanguíneo cerebral de ese mismo momento y voila: música para los oídos. O mejor dicho, jazz para los oídos.

Lo que hicieron fue utilizar las imágenes del encefalograma para crear los tonos y la duración de las notas y las imágenes de la resonancia magnética para controlar su intensidad a través de un software especial.

"La terapia musical sería una buena aplicación de la música cerebral", señaló Jing Lu, a cargo de la investigación en la que también participaron otros seis expertos del Laboratorio Clave para NeuroInformaciónn del Ministerio de Educación de China, la Facultad de Ciencias de la Vida y Tecnología de la Universidad de Ciencia Electrónica y Tecnología de China, el Conservatorio de Música de Sichuan, el Centro de Ciencias de la Vida y los Institutos de Ciencias Biológicas de Shanghai de la Academia China de Ciencias.

"Creo que esta será una maravillosa aplicación si ampliamos la investigación", agregó el científico que utilizó para este experimento a una mujer de 31 años y a una adolescente de 14.

Los expertos creen que en el futuro podrían aprovechar la misma música cerebral para ayudar a las personas a controlar sus propias ondas cerebrales y aliviar así problemas de ansiedad y depresión.

Precisamente, se conoce como terapia de biorretroalimentación, aquella en la que los pacientes se esfuerzan para controlar conscientemente la actividad cerebral, explicaron los científicos.

Pero los investigadores chinos no se quedaron solo con sus oídos y pusieron la melodía bajo análisis de expertos. Un panel de 10 músicos la escuchó en profundidad y señaló que la música cerebral sonaba como si hubiese sido obra de un eximio compositor.

Fuente:

http://www.clarin.com/sociedad/suena-cerebro-piensa_0_813518837.html

Ritmos y sonidos en el Corazón

noreply@blogger.com (Unknown) — Mon, 07 Mar 2016 20:50:00 +0000

Los ruidos cardiacos son los escuchados en la auscultación cardiaca. Normalmente son dos ruidos (1º y 2º) separados entre sí por dos silencios (pequeño y gran silencio respectivamente). En algunas ocasiones se puede percibir la existencia de un tercer ruido, y menos frecuentemente un cuarto ruido.

En suma, los ruidos cardíacos se deben a los cierres de las válvulas en el interior de los ventrículos o del comienzo de las grandes arterias y que por su intensidad se propagan a las paredes del tórax; allí el oído los capta como ruidos.

Primer Ruido

Coincide con la iniciación del choque de la punta y corresponde al comienzo de la sístole ventricular. Es más profundo y largo que el segundo y se percibe con más claridad en los focos de la punta.se llama sistole

Resulta del cierre de las válvulas mitral y tricúspide y de la apertura de las aórticas y pulmonares, además del inicio de la contracción ventricular.

La causa principal reside en que la sangre, impulsada violentamente contra las válvulas auriculo-ventriculares, a las que cierra, retrocede contra las paredes del ventrículo, vuelve sobre las válvulas nuevamente, etc; se producen así, vibraciones de la sangre y de las paredes ventriculares que, propagadas, constituyen la base física del primer ruido.

Normalmente, la válvula mitral se cierra discretamente antes que la tricuspidea, no percibiéndose ambos componentes por separado, por ser la diferencia de tiempo muy escasa. En circunstancias anormales, puede aumentar esta diferencia y se perciben los dos componentes (desdoblamiento del primer ruido).Otras veces, el cierre se produce con más fuerza, apareciendo un ruido más nítido y puro (refuerzo del primer tono).

Segundo Ruido

Coincide con el comienzo de la diástole ventricular y se percibe con mayor nitidez en los focos de la base cardiaca. Es el resultado del cierre de las válvulas sigmoideas o semilunares (aórtica y pulmonar), y de la apertura de las válvulas auriculoventriculares (tricúspide y mitral).

Al igual que ocurre en el primer ruido, los dos componentes principales de este segundo ruido no son simultáneos en el tiempo, sino que ocurren con un escasa diferencia no perceptible. En condiciones anormales se puede acentuar esta diferencia, percibiéndose entonces separados (desdoblamiento del segundo ruido), esto ocurre porque se retrasa el cierre de la válvula pulmonar. También puede percibirse anormalmente un refuerzo del segundo tono análogamente como ocurre en el primero.

En situaciones especiales, particularmente en pacientes pediátricos, el desdoblamiento del segundo tono es frecuente y normal. Además, el desdoblamiento normal de T2 puede darse al auscultar pacientes adultos sin cardiopatía, asociándose a la inspiración. La explicación de este fenómeno está en relación con el descenso diafragmático que aumenta la presión intraabdominal (disminuyendo a su vez la intratorácica) y el incremento subsecuente del retorno venoso hacia cavidades derechas. Este aumento de volumen sanguíneo en el ventrículo derecho conlleva un mayor tiempo sistólico y un retraso en el cierre de la válvula.

En caso de estenosis mitral o tricuspidea, podemos percibir la existencia del denominado chasquido de apertura (ruido concomitante con la apertura de las válvulas auriculoventriculares que normalmente no se oyen). Tienen las mismas características que el segundo ruido y se escuchan inmediatamente a continuación del mismo.

Tercer Ruido

Se escucha en algunas ocasiones, generalmente en niños, en los que no suele señalar patología. Se trata de un ruido diastólico que ocurre después del segundo tono y tiene una frecuencia muy baja. Es causado por llenado brusco del ventriculo, debido a una velocidad de flujo aumentada, un volumen de sangre aumentado. Es compatible con insuficiencia mitral o tricuspidea.

Cuarto Ruido

Es mucho menos frecuente y suele tener un significado patológico. Es un ruido presistólico que se escucha antes que el primero normal y se debe a la vibración producida por la contracción auricular contra un ventriculo poco distensible. Es de frecuencia muy baja y se escucha mejor en la punta.

Silencios

Los ruidos cardiacos normales están separados entre sí por silencios:

- Pequeño silencio: entre el primero y el segundo tono. Coincide con la sístole ventricular.

- Gran silencio: entre el segundo y el primero del ciclo siguientes. Coincide con la diástole ventricular.

En circunstancias anormales, estos silencios pueden estar ocupados, hablando entonces de la existencia de un soplo cardíaco.

Fuente:

http://es.wikipedia.org/wiki/Ruido_card%C3%ADaco

The sounds of Drongos (african brids)

noreply@blogger.com (Unknown) — Fri, 04 Mar 2016 18:31:00 +0000

By Will Dunham,

May 1, 2014

(Reuters) - If you believe honesty is the best policy, you would have a hard time convincing the forked-tailed drongo. This tricky African bird is the pathological liar of the animal kingdom.

Scientists described on Thursday how this medium-sized bird brazenly deceives other animals by mimicking alarm calls made by numerous bird species - and even meerkats - to warn of an approaching predator in a ruse to frighten them off and steal food they leave behind.

The researchers tracked 64 forked-tailed drongos over a span of nearly 850 hours in the Kalahari Desert in South Africa close to the Botswana border to unravel this unique behavior.

"They're rather demonic little black birds with red eyes, a hooked beak and a forked tail," said evolutionary biologist Tom Flower of the University of Cape Town in South Africa.

"They're also highly aggressive and are renowned for attacking eagles and hawks, for which they apparently have no fear," added Flower, whose study appears in the journal Science.

These birds, common in southern Africa, usually get meals the honest way, such as capturing insects in mid-air using their superb aerial skills.

But at other times, like on cold mornings when few insects are flitting around, the drongos turn to a life of crime.

FALSE ALARM

The drongos are able to mimic the sounds made by many different species that inhabit its desert environment, including birds such as pied babblers, glossy starlings, sociable weavers and pale chanting goshawks as well as mammals like meerkats.

The drongos carry out an elaborate con. They give their own genuine alarm call when they spot a predator approaching - essentially behaving as sentries - and other animals come to trust that this call signals real danger.

But they sometimes give this alarm call when no danger exists to fool other animals into fleeing and abandoning their food.

Then the drongos swoop down for a free lunch.

"All the animals in the Kalahari eavesdrop on each other's alarm calls, which provide invaluable information about potential predators. It's a bit of an information superhighway where all the animals speak each other's language," Flower said.

"Because drongos give reliable predator information some of the time, it maintains host responsiveness (of other animals) since they can never know if the drongo is lying or telling the truth," added Amanda Ridley, an evolutionary biologist at the University of Western Australia, another of the researchers.

The scientists noticed that sometimes the other animals ‘get wise’ to the con and ignore repeated false alarm calls. But then the wily drongos simply grab another tool from their toolbox of trickery - they mimic the alarm calls made by other animals, once again conning them into fleeing and leaving their chow behind.

Flower observed drongos mimicking more than 50 calls.

When stealing food from other animals, drongos are able to eat larger prey than they normally would be able to capture on their own like scorpions, beetle larvae and even geckos.

"Crime pays," Flower said, noting that the stolen stuff accounted for about a quarter of the food eaten by the drongos.

"One could argue that the strategy of the drongo to steal food from others seems very dishonorable in human standards. But, yes, if it has found such a crafty way to catch food, which is usually much larger than the food items it catches itself, then we cannot help but admire this clever little bird's adaptiveness," Ridley added.

The researchers classify the drongo as "a kleptoparasite."

There are many examples of mimicry and deception in the animal kingdom. About 20 percent of song birds mimic the calls of other birds, Flower noted.

"However, drongos are the only ones to flexibly produce the specific signals that best deceive their different hosts and to maintain their deception racket by changing signal when the previous signal failed," Flower added.

Source: http://news.yahoo.com/liar-liar-african-bird-uses-elaborate-ruse-steal-012320898.html
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Giant Waves from the Sun's Atmosphere

noreply@blogger.com (Unknown) — Thu, 03 Mar 2016 20:30:00 +0000

by Megan Gannon, News Editor
June 28, 2014

The sun's volatile atmosphere is even bigger than expected, a NASA spacecraft revealed through observations of gigantic waves.

While the sun itself is 864,938 miles (1.392 million kilometers) wide, NASA's Solar Terrestrial Relations Observatory, or STEREO, found that the solar atmosphere, known as the corona, stretches 5 million miles (8 million km) above the sun's surface.

'We've tracked sound-like waves through the outer corona and used these to map the atmosphere,' Craig DeForest of the Southwest Research Institute in Boulder, Colorado, said in a statement from NASA. 'We can't hear the sounds directly through the vacuum of space, but with careful analysis we can see them rippling through the corona.'

These waves, called magnetosonic waves, are a cross between sound waves and magnetic waves called Alfven waves. They oscillate only about once every four hours and span 10 times the width of Earth, NASA officials said.

When magnetosonic waves erupt from solar storms and other disturbances, they can ripple up to 5 million miles away from the sun's surface, DeForest and colleagues found. Beyond this boundary, solar material separates from the corona and flows out into space in a steady stream known as the solar wind.

NASA officials say the findings will help researchers prepare for the space agency's Solar Probe Plus mission, scheduled to launch in 2018. That mission will send a spacecraft closer to the sun that any man-made object has ever ventured — within 4 million miles (6.4 million km) of the sun's surface. Now, scientists know the probe will actually be traveling through the corona during its historic trip.

"This research provides confidence that Solar Probe Plus, as designed, will be exploring the inner solar magnetic system," Marco Velli, a Solar Probe Plus scientist at NASA's Jet Propulsion Laboratory in Pasadena, California, said in a statement. 'The mission will directly measure the density, velocity and magnetic field of the solar material there, allowing us to understand how motion and heat in the corona and solar wind are generated.'

The findings, which were published last month in The Astrophysical Journal, should also help astronomers define the inner boundary of the heliosphere, the giant bubble enveloping the solar system, created by the solar wind and solar magnetic field.

Source: http://news.yahoo.com/giant-waves-reveal-surprising-true-size-suns-atmosphere-110626451.html