Thanks to a cold environment, which causes a slow metabolism, bowhead whales (Balaena mysticetus) can live for more than 200 years - nearly 3 times longer than the average human, making it the longest-lived mammal.
Bowhead whales can grow 14 to 18 m (46 to 59 ft) in length, and unlike most whales, they lack a dorsal fin. This thick-bodied species can weigh from 75 to 100 tonnes (82 to 110 US tons). They live entirely in fertile Arctic and sub-Arctic waters, unlike other whales that migrate to low latitude waters to feed or reproduce. The bowhead also has the largest mouth of any animal.
Of course, following around a whale to measure how long it lives is practically impossible. Researchers discovered this amazing feature in 2007, when a 15 m [ ... ]
Researchers have discovered a new compound, named 'darwinolide', inside an Antarctic sponge, Dendrilla membranosa (above, middle), that has shown to kill 98.4 percent of methicillin-resistant Staphylococcus aureus (MRSA) cells it comes in contact with. Lab tests so far suggest that it has a unique structure that allows it to penetrate the 'biofilm' that MRSA throws up to protect itself from treatments.
The next step is to synthesise darwinolide in the lab, so they don't have to rely on extracting it from live Antarctic sponges. If the researchers are able to show that they can use darwinolide to fight MRSA in a clinical setting, it could save the lives of tens of thousands of people every years.
To take the zap out of a school of electric eels, fishermen in 17th century South America sent teams of horses into the water as bait, scooping up the eels after they had exhausted themselves in the attack. According to famed naturalist Alexander von Humboldt, the eels would leap out of the water to shock the frightened - but mostly unharmed - horses. Until now, no one else had recorded evidence of such behavior, and many scientists were skeptical of Von Humboldt’s account. A new study shows that not only do the animals leap from the water to attack their prey, but they also increase their voltage as they leap (see video below). The jumping behavior was first observed by accident: As scientists were studying the eels in an unrelated exper [ ... ]
For decades, scientists have debated whether rapid eye movement sleep - the phase where dreams appear - is directly involved in memory formation. Now, a study provides evidence that REM sleep does, indeed, play this role in mice.
In this new study, the researchers used optogenetics, a recently developed technology that enables scientists to target precisely a population of neurons and control its activity by light. For this study, the neurons in the hippocampus were targeted (hippocampus being the structure that is critical for memory formation during wakefulness and is known as the 'GPS system' of the brain).
To test the long-term spatial memory of mice, the scientists trained the rodents to spot a new object placed in a controlled environm [ ... ]
A non-Newtonian fluid is a fluid with properties that differ in any way from those of Newtonian fluids - it changes its viscosity almost instantly under stress, so you can punch it as a liquid and it’ll turn into a solid (watch the video below), and you can literally walk across a pool of it. On the contrary, a Newtonian fluid is defined as the perfect fluid, where its viscosity is influenced mostly by its temperature and pressure. So if you have water at a moderate temperature and pressure, it will continue to act like a liquid no matter how much you punch it. Depending on how you manipulate it, the fluid-like substance can change states from a liquid to a solid, but how this happens has remained a conundrum amongst physicists.
According to a study published in the medical journal eLife, researchers found that specific combinations of gut bacteria produce substances that affect myelin content and cause social avoidance behaviors in mice.
Researchers transferred fecal bacteria from the gut of depressed mice to genetically distinct mice exhibiting non-depressed behavior. The study showed that the transfer of microbiota was sufficient to induce social withdrawal behaviors and change the expression of myelin genes and myelin content in the brains of the recipient mice.
In an effort to define the mechanism of gut-brain communication, researchers identified bacterial communities associated with increased levels of cresol, a substance that has the ability to pass the bloo [ ... ]
For the first time, scientists have discovered a link between heavy marijuana use and reduced dopamine production. Just so you know, dopamine is the hormone/neurotransmitter that is released during any kind of satisfaction - it's the same hormone that is released in your brain when you eat chocolate. In a recent study, lower dopamine release was found in the striatum - a region of the brain that is involved in working memory, impulsive behavior, and attention, in addition to subregions involved in associative and sensorimotor learning, and in the globus pallidus. Previous studies have shown that addiction to other drugs of abuse, such as cocaine and heroin, have similar effects on dopamine release, but such evidence for cannabis was mis [ ... ]
The creature you see above is a spider that can actually surf on top of waves and hunt for a wide variety of animals including not only insects but also fish and toads. Dubbed the Dolomedes briangreenei, this species of spider floats on top of water and senses vibrations below to detect potential prey. The spider can even submerge itself underwater for up to an hour to hunt down prey, which makes it doubly frightening for any creatures caught in its path. The largest animals that the spider has been known to eat are cane toads, which can measure up to nine inches in length. For comparison, the D. briangreenei is about the size of a human palm. [ ... ]
Academics from seven universities across the world studied Christian, Muslim, and non-religious children to test the relationship between religion and morality. They found that religious belief is a negative influence on children’s altruism (link below). Even more, religiousness predicts parent-reported child sensitivity to injustices and empathy, and children from religious households are harsher in their punitive tendencies.
The authors of The Negative Association Between Religiousness and Children’s Altruism Across the World, published this week in Current Biology note that their findings "contradict the commonsense and popular assumption that children from religious households are more altruistic and kind towards others." More generally [ ... ]
Vibratory urticarial is a ultra rare genetic condition that cause people to break out in hives if their skin is vigorously vibrated or rubbed. In fact, even drying yourself with a towel can cause hives, make your face flush, give you headaches, or produce the sensation of a metallic taste. According to a new study published this week, researchers found a mutation in a gene called ADGRE2 that codes for a receptor protein found on the surface of mast cells - immune cells in the skin that dump out inflammatory molecules such as histamines that increase blood flow to an area and can cause hives. The researchers observed that shaking mast cells in a dish breaks apart two subunits of this receptor protein, which prompts histamine release. In p [ ... ]
The magic number is 42 m/s (94 mph). Using mathematical data and physical experiments, scientists say they have found the law that governs the resistance of wooden beams under stress. According to the study (link), researchers hung weights from wooden rods and pieces of pencil lead to record the amount of force needed to snap the cylinder. As one might sense, they found that for a fixed length, increasing the diameter made the rods stronger: They could bend more before breaking. This would make tall skinny trees most vulnerable, but, as the team points out, trees don’t grow taller without getting disproportionately thicker as well. By incorporating established laws of tree allometry - which explain the relationship of tree size parameters [ ... ]
A landmark study, based on genetic analysis of nearly 65,000 people, has revealed that a person's risk of schizophrenia is increased if they inherit specific variants in a gene related to "synaptic pruning" - the elimination of connections between neurons. The findings represent the first time that the origin of this devastating psychiatric disease has been causally linked to specific gene variants and a biological process. They also help explain decades-old observations: synaptic pruning is particularly active during adolescence, which is the typical period of onset for schizophrenia symptoms, and brains of schizophrenic patients tend to show fewer connections between neurons. The gene, called component 4 (C4), plays a well-known role in t [ ... ]
You've probably heard the saying 'don't eat yellow snow', for obvious reasons. Unfortunately, according to a new study published in the journal Environmental Science: Processes & Impacts, you shouldn’t eat any snow. Snow has been found to act as a rather effective sink for tiny particles that are found primarily in car exhaust fumes, so any consumption of it is effectively like eating a pollution-flavored Popsicle.
Researchers of this study found that from just one hour of exposure, the levels of pollutants within the snow increased dramatically, with toxic particles becoming trapped within the small ice particles or dissolved within pockets of meltwater. This means that snow is a particularly effective “sink” for car exhaust pollution.
Dog owners often say they "know" that their dog understands what they’re feeling. Now, scientists have the evidence to back this up. Researchers tested 17 adult dogs of various breeds to see whether they could recognize emotional expressions in the faces and voices of humans and other dogs - an ability that’s considered a higher cognitive talent because two different senses are involved. Each dog took part in two test sessions with 10 trials. One by one, they stood facing two screens on which the researchers projected photos of unfamiliar but happy/playful human or dog faces versus the same faces with angry/aggressive expressions (as in the photo above). At the same time, the scientists played a single vocalization - either a dog bark, [ ... ]
Proteins are subatomic biomolecules. They're produced by cells, so it's logical to assume that they are much tinier than cells, and of course, much tinier than the organelles that produce them. In a remarkable achievement, scientists have now obtained the first-ever photographs of single proteins. Using a "holography electron microscope," researchers tested on a range of protein samples, all just a few nanometers in size. Hemoglobin, the protein that transports oxygen in red blood cells, and cytochrome c, the protein that transfers electrons within the body, were just two examples.
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