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The Raelian Movement
for those who are not afraid of the future : http://www.rael.org
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Source: http://natmonitor.com/news/silver-colored-fish-go-invisible-to-thwart-predators/
Silver-colored fish go invisible to thwart predators
By Todd Bogle, Staff Writer / October 23, 2012
Silver-colored fish go invisible to thwart predators, according to researchers at Bristol University. The law of reflection dictates that reflective surfaces polarize light, a law that fishermen or photographers have to deal with by using polarizing sunglasses or polarizing filters to eliminate reflective glare.
Silver-colored fish go invisible to thwart predators, according to researchers at Bristol University. The law of reflection dictates that reflective surfaces polarize light, a law that fishermen or photographers have to deal with by using polarizing sunglasses or polarizing filters to eliminate reflective glare.
Researchers were surprised to find that the skin of silver-colored fish “breaks” this well-known law of physics. Fish’s skin has “multilayer” arrangements of guanine crystal. Researchers had previously thought that fish’s skin would fully polarize light when reflected.
However, the researchers discovered that the skin of silver-colored fish actually contains two types of guanine crystal. These two types of guanine crystal, when mixed, prevent the fish’s skin from the polarizing the reflected light. This mixture helps the fish’s skin maintain its high reflectivity.
“We believe these species of fish have evolved this particular multilayer structure to help conceal them from predators, such as dolphin and tuna. These fish have found a way to maximize their reflectivity over all angles they are viewed from. This helps the fish best match the light environment of the open ocean, making them less likely to be seen,” said Dr Nicholas Roberts of Bristol University’s School of Biological Sciences in a statement.
Researchers believe that their findings could help engineers change the way that modern day optical devices are manufactured.
“Many modern day optical devices such as LED lights and low loss optical fibres use these non-polarizing types of reflectors to improve efficiency. However, these man-made reflectors currently require the use of materials with specific optical properties that are not always ideal. The mechanism that has evolved in fish overcomes this current design limitation and provides a new way to manufacture these non-polarizing reflectors,” said PhD student Tom Jordan in a statement.
The study is described in detail in the journal Nature Photonics.
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"Ethics" is simply a last-gasp attempt by deist conservatives and
orthodox dogmatics to keep humanity in ignorance and obscurantism,
through the well tried fermentation of fear, the fear of science and
new technologies.
There is nothing glorious about what our ancestors call history,
it is simply a succession of mistakes, intolerances and violations.
On the contrary, let us embrace Science and the new technologies
unfettered, for it is these which will liberate mankind from the
myth of god, and free us from our age old fears, from disease,
death and the sweat of labour.
Rael
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