January 6th, 2012 at 10:45PM
Devil by Grzegorz Cywicki It’s called Violin Mantis! 

Devil by Grzegorz Cywicki

It’s called Violin Mantis! 

9 notes Source: 500px.com #animals#macro#photography#violin mantis#insects
November 2nd, 2011 at 2:37PM
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

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

22 notes Source: leonardosreef.com #biology#diffraction#eye#insects#lens#light#optics#physics#Science