MessageToEagle.com - Researchers studying small creatures and flying insects are often amazed over their capability
to perform a great variety of different maneuvers and how they manage to avoid dangers and keep away from areas where they
will be highly visible.
In our article we described an amazing, only a few inches long fish
tirelessly working day and night to carve the circular ridges with its flapping fin.
Now, nature surprises us once again. Certain fish species break the law of physics to keep safe from predators and among them are
silvery fish such as herring, sardine and sprat.
According to new research conducted by PhD student Tom Jordan and his supervisors Professor Julian Partridge and
Dr Nicholas Roberts in Bristol's School of Biological Sciences, these silvery fish have overcome this basic law of
reflection – an adaptation that may help them evade predators.
Reflective surfaces polarize light, a phenomenon that fishermen or photographers overcome by using polarizing
sunglasses or polarizing filters to cut our reflective glare.
Previously, it was thought that the fish's skin – which contains "multilayer" arrangements of reflective guanine crystals –
would fully polarize light when reflected. As the light becomes polarized, there should be a drop in reflectivity.
The Bristol researchers found that the skin of sardines and herring contain not one but two types of guanine crystal –
each with different optical properties. By mixing these two types, the fish's skin doesn't polarize the reflected light
and maintains 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,"
according to Dr Roberts.
As a result of this ability, the skin of silvery fish could hold the key to better optical devices.
"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," Tom Jordan said.
Lake In France Turns Red
This year, we have encountered the color red in places where we don't expect to see it. A while back the strange appearance
of Azov Sea stunned residents who saw how the water had turned red. The red rocks in China have also puzzled scientists for a long time.
Now, a lake in Southern France has also suddenly turned red.
An Incredible Geological Phenomena
Earth is an amazing planet and our nature is full of wonders. We have previously written about incredible singing plants.
This time we would like to focus our readers' attention on another amazing geological phenomena, namely so-called growing stones.
It is difficult to image that stones can really grow, but these stones seem to be alive!
Yangtze River In China Turns Red
We have seen on a couple of occassions how lakes and seas have suddenly turned red.
In August a lake in Southern France unexpectedly changed color and shortly before that the strange appearance of
Azov Sea stunned residents who saw how the water had turned red....