Chimpanzee hands by Tambako the Jaguar on Flickr.
Is not a secret that we Humans share 96% of genome with chimps.
(via fyeahgreatapes)
Staring directly into the eyes has a powerful intimidating effect, and many species have evolved staring eye-spots as self-defense mechanisms. Many moths have a pair of startling eye-markings on their wings. These lie concealed until the creatures are attacked by predators. The wings then open and flash the bright eye-spots in the face of the enemy. It has been proved experimentally that this exerts a valuable intimidating influence on the would-be killers, who frequently flee and leave the insects unmolested.
It’s amazing how well defined the eye-spots are.
How does the gecko climb walls and walk on the ceilings?
Robert Full and Keller Autum have discovered that gecko lizard’s ability to climb up smooth walls and ceilings can be traced to millions of microscopic hairs (as seen above) on the lizard’s toes called “setae”. But without miniature hooks in the walls or ceiling (like in Velcro), what holds the fibers and attached gecko in place? Something called: Static cling!
The fibers in a gecko’s feet are electrically neutral, but the lizard does not need to shuffle across a shag carpet (to get negative charge) to cling to a wall, because he makes use of fluctuations of charge in his setae. The electrons in the fibers in the gecko’s toes are constantly zipping around. Sometimes a few more electrons are on one side of the fiber, making that side slightly negatively charged, while other times a few less electrons are on that side making it slightly positively charged.
If the side of the fiber closer to the wall is, just for a moment, slightly negatively charged, then it will induce a slight positive charge in the wall (by repelling those electrons in the wall close to the surface, exposing the positive charge ions) and an attractive force between the fiber and the wall will result (like the magnets n the fridge). This force is known as the Van der Waals force, and indeed is very weak, and that is the reason why the gecko has millions of these fibers in each toe, so that the total attractive force can be large enough to support the gecko weight.
Scientists today have developed a material that mimic the gecko feet, and can have a number of applications, including feet for wall-climbing robots, and in outer space, where most adhesives don’t work because of the vacuum.
Truth be said, I enjoy a lot writing this post, it is really fascinating how it works.
Bibliography: Physics of superheroes by James kakalios
Photosynthesis.
I was reading a book about energy.
If you think deep of all the things you eat, it´s easy to find that the main origin of everything is a plant.
Let´s say you are eating a steak, well the cow ate before grass and some seeds.
Now you are eating chicken, well the chicken ate some seeds also.
Now you are eating fish, well the fish ate other fish or some placton, or some algae.
All the things we eat, are solar energy converted in let´s say (for sake of simplicity) “packets of energy” in form of macromolecules by plants by means of Photosynthesis. Then, we eat this packets of energy from plants, or we eat this packets in form of chicken, fish steak or anything.
I believe Photosynthesis is a corner stone process of life.
I believe in Photosynthesis.
Isaac Asimov, wrote a lot of books, I highly recommend to read this author, He is great at explaining things in simple ways.
Why does the insects does not have an eye similar to us even tough we share nearly 60% of human genes with the fruit fly (Drosophila melanogaster)?
Well, let’s say that nature is very wise.
On average, white light —which consist of light of all wavelengths from red (650 nanometers) to violet (400 nanometers) added together in equal magnitudes — has a wavelength of 500 nanometers (1 nanometer is 0.000000001 meters). In order for light to be detected, it must hits the rods and cones on the back of your eye, and in order to get to these photoreceptors, it must first pass through your pupil. The pupil opens and closes depending of light, but is roughly 5 milimeters in diameter. So the opening in your pupil is ten thousand times larger than the wavelength of the visible light and it passes without problems.
Now imagine that now you shrink to the size of an insect, and you will be 300 hundred times smaller, also the pupil in your eye will be 300 hundred times smaller that is ~16000 nanometers that is only 30 times larger than the wavelength of the white light. So the light still fit in the pupil but just barely.
If you ever have used a manual camera controlling the aperture, you notice that the smaller the aperture the image gets blurring, even though you still have light.
So, in physical terms the waves of light still passes through your pupil, but some of them scatter on the edge of your pupil, and this setup an interference pattern inside the eye, this effect is called “diffraction” and is most noticeable when the dimensions of the object scattering a wave are comparable to the wavelength.
So what you see, when you are the size of an insect is that everything is blur and out of focus, and this is why insect’s eye, and in particular it’s lens, is radically different from the lens in humans. Insects use compound lenses that adjust to diffraction effects (What you see in the image above is that the eye is compound of many hexagon lenses). In fact insects are very good at detecting changes (hard to catch) in light, but poor at detecting the contrast between sharp edges.
Bibliography: “Physics of superheroes” James Kakalios
Spigots of a spider in false color.
Electron microscope image of a spider’s silk spigots.
Let’s put this in plain words. This is a photography with really really high resolution, of the tail of a spider. On it you can see a lot of tubes, and some liquid coming out from them, well this is the silk-webbing. As you can see the webbing is made from a lot of filaments, and thus giving some robustness.
Dragline silk webbing, wich spiders and while rapidly fleeing birds, is actually five times stronger per pound than steel cable, and more elastic than nylon.
The webbing’s properties result from thousands of rigid filaments only a few billionths of a meterwide (providing great redundancy so that no one filament is crucial for the integrity of the webbing), interspersed with fluid-filled channels that distribute the tensile force along the length of the webbing.
Spiders can control the tensil strength of their webs by varying the relative concentration of crystallizing and non crystallizing proteins.
Jim Robins in his article “Second Nature” in July 2002 issue of Smithsonian says: “In theory a braided silk-rope the diameter of a pencil, could stop a fighter jet landing on an aircraft carrier. The combination of strength and elasticity allows it to withstand an impact five times more powerful than kevlar, the synthetic fiber used in bullet proof vests.”
So, it looks very plausible that Spider-Man can swing from building to building with spider webbing.
Source: “The physics of superheroes” by James Kakalios
The shape of the mouth of this bird is a quirk of nature.
It’s a Roseate Spoonbill.
This book is the most complete—and, it must be said, moving— catalog of animal extinctions from the last three hundred years.
Metal working model used by James Watson and Francis Crick to determine the double-helical structure of the DNA molecule in 1953.
These four persons and Linus Pauling in someway, helped to discover the DNA.
The only ones who were awarded with the Nobel Prize in 1962 were: James, Francis and Maurice, by 1962 Rosalind was already dead. Nobel Prizes are not awarded posthumously.
Just for your information: James Watson is still alive, and he has 83 years.
