Located in Hamelin’s Pool, a shallow area of Shark Bay in Western Australia, these odd formations aren’t rocks—they’re stromatolites, and they were built over millennia by single-celled cyanobacteria (also known as blue-green algae). 4,000 to 6,000 years ago, a huge bank of seagrass began to block the tidal flow into Hamelin’s Pool, which meant that the water became twice as salty as the open ocean. Animals like snails and chitons that would usually feed on the algae couldn’t survive, so the blue-green algae began to flourish. Gathered in colonies, they trapped sediment with their sticky surface coatings. This sediment reacted with calcium carbonate in the water and formed limestone, essentially creating a living fossil—this limestone is alive, its top surface layer teeming with active cyanobacteria. The limestone builds up slowly at a rate of about 1mm per year. The stromatolites in Shark Bay are estimated to be between 3,000 and 2,000 years old, but they’re similar to life forms in Precambrian times, 3.5 billion years ago, at the dawn of complex organisms. There are over 50 kinds of cyanobacteria in Shark Bay, and one is thought to have descended from an organism that lived nearly 2 million years ago, making it a part of one of the longest biological lineages.
I normally abhor the term “living fossil” but I’ll let it slide this time because AWESOME. Like little prokaryotic time capsules.
Via It's Okay To Be Smart
- from Scientific American
“Whatever your beliefs, most people would agree that the body left behind when we depart this mortal coil is just a heap of bones and flesh. But what happens to those leftovers? Assuming that nature is left to its own devices, our bodies undergo a fairly standard process of decomposition that can take anywhere from two weeks to two years.”
Written & narrated by Mark Fischetti
Assistant editor: Kathryn Free
Produced, edited & animated by Eric R. Olson
(Source: Scientific American)
I can’t wait to be a tree. Well, actually I CAN wait, but it’s gonna be cool when it happens.
Via It's Okay To Be Smart
First photograph ever taken by phosphorescent light. The face is that of Mr. Tesla, and the source of light is one of his phosphorescent bulbs. The time of exposure, eight minutes. Date of photograph January, 1894.
Tesla was just a cool photo machine, eh?
Here he is with his friend Mark Twain:
And here he is with his friend electricity:
The relation between the pelvis and the pelvic organs of the female
With so many sex ed textbooks and encyclopedias giving the standard “vertical cross section” view of the pelvis, or showing the organs without any context, it can be difficult to see in the mind exactly where everything lays.
In this diagram, "P" indicates the part of the sacrum that is both at its top, and farthest “forward” in the body. Below that point, it curves backwards.
"S" is the pubic symphysis, which is the joint that brings together the two sides of the pelvis. It’s largely immobile, but very slightly stretchable with trauma or childbirth.
"F" is the fundus of the uterus - a fundus is the part of a hollow organ that is farthest from its opening.
"O" is the ovary, embraced (but not touched) by the fallopian tubes.
"R" is the rectum, the lowest section of the intestine, which travels behind the reproductive organs.
"B" is the bladder, which lays in front of the reproductive organs.
There are two primary parts to the pelvis: the pelvic spine, which includes the sacrum and coccyx; and the pelvic girdle, which is probably what you associate with “pelvis” - this is the two “pelvic bones”, the hip bones or coxal bones.
As children, we have six hip bones - three on each side. The ilium (the big “wing” part, where the abdominal muscles attach), the pubis (that upper part of the “eyes” in the pelvis), and the ischium (the lower bit of the “eyes”, the “sit bone”). By age 25, all three sections have fused together, leaving us with just two hip bones.
An American Text-Book of Obstetrics for Practitioners and Students. Edited by Richard C. Norris, 1895.
random fact: the uterus and the fallopian tubes look nothing like this “rendition” at all, the fallopian tubes are long and thinner than angel hair pasta, and the uterus is also quite tiny.
True! However, the uterus in this rendition is WAY smaller than the vast majority of contemporary illustrations. It’s much closer to what a non-pregnant woman would look like than most illustrators put.
But yeah, the ovaries are surprisingly far-yet-not-far from the fallopian tubes, which are tiny little things with spindly little fingers at the end. In living women, standing up, the uterus is usually not even visible from the front, if they’re not pregnant. The size increase of the uterus from implantation to parturition is amazing and almost terrifying (okay, at least to me). However, the fallopian tubes remain basically the same throughout the entire life, unless they’re “tied” or removed.
Think you’re a smart shopper? What if I told you that your buyer’s brain could be tricked by something as simple as color?
We’ve evolved natural reactions to some colors (like red for blood, or anger, or sexual fertility), and we’ve been culturally adapted to many others, so it’s no surprise that color can subtly influence our behavior.
Don’t buy it? Let BrainCraft explain!
When light travels through areas of different air density, it bends. You’ve probably noticed the way distant pavement seems to shimmer on a hot day, or the way stars appear to twinkle. You’re seeing light that has been distorted as it passes through varying air densities, which are in turn created by varying temperatures and pressures.
Schlieren Flow Visualization can be used to visually capture these changes in density: the rising heat from a candle, the turbulence around an airplane wing, the plume of a sneeze … even sound. Special thanks to Mike Hargather, a professor of mechanical engineering at New Mexico Tech, who kindly provided a lot of these videos.
I’m totally Schlieren right now. Amazing sights of sounds.
Via It's Okay To Be Smart
As someone who wants to study the human consciousness I found this very interesting.
Scott Routley was a “vegetable”. A car accident seriously injured both sides of his brain, and for 12 years, he was completely unresponsive.
Unable to speak or track people with his eyes, it seemed that Routley was unaware of his surroundings, and doctors assumed he was lost in limbo. They were wrong.
In 2012, Professor Adrian Owen decided to run tests on comatose patients like Scott Routley. Curious if some “vegetables” were actually conscious, Owen put Routley in an fMRI and told him to imagine walking through his home. Suddenly, the brain scan showed activity. Routley not only heard Owen, he was responding.
Next, the two worked out a code. Owen asked a series of “yes or no” questions, and if the answer was “yes,” Routley thought about walking around his house. If the answer was “no,” Routley thought about playing tennis.
These different actions showed activity different parts of the brain. Owen started off with easy questions like, “Is the sky blue?” However, they changed medical science when Owen asked, “Are you in pain?” and Routley answered, “No.” It was the first time a comatose patient with serious brain damage had let doctors know about his condition.
While Scott Routley is still trapped in his body, he finally has a way to reach out to the people around him. This finding has huge implications.
Via Talking Shrimp
MYTH: Once your brain cells die, they can’t grow back. The brain does not change.
This follows the myth that you are born with all the neurons you’ll ever have. In fact, some neurons do regenerate and/or change. If they couldn’t, you’d have lost your sense of smell years ago! Not to mention, you’d never be able to form new memories or learn new things.
In the neuroscience community, we often discuss this with terms like “neurogenesis” and brain “plasticity.” Meaning that new neurons can grow (neurogenesis) and can change (plasticity) with time. Adult neurogenesis in mammals appears to occur in the olfactory bulb (these neurons have frequent turnover, due to their exposure and death) and the hippocampus- the part of the brain that creates memories (more info here). There is evidence that it may happen elsewhere in the brain too (for instance, this paper in Cell showed that it happens to interneurons in striatum).
However, unfortunately, some nerves can’t repair themselves or regrow once damaged in adulthood (like those in the spinal column). Not all neurons are like this, and sometimes they can repair themselves with partial damage but not when completely damaged, as comes into play with paralysis and Alzheimer’s disease. The field is still learning about these and which factors make them irreparable or irreplaceable. Maybe one day we’ll be able to fix all neural damage (people are investigating how to do this now! We’re not close to a cure, but others are beginning to understand this better).
For now, it’s important to know that this absolute statement is a myth, and some neurons do regrow- and our brain is changing all the time, as we learn new things and experience new memories.