Tiny freshwater fish have a view of the world that blows Google Street View out of the water - using different parts of their eyes to deliver optimum uses of colour, black-and-white and ultraviolet.
A zebrafish view of the world has been forensically analysed by researchers at the University of Sussex to reveal that how they see their surroundings changes hugely depending on what direction they are looking.
The study of the colour vision system of zebrafish larvae, published today in Current Biology, reveals they use their near 360 degree view of their world to detect threatening silhouettes above them in black-and-white but can seek out the almost transparent single-cell organisms they feed on by detecting the scattering of light in UV.
Dr Tom Baden, a senior lecturer in neuroscience at the University of Sussex who led the research, said: "By measuring the activity of thousands of neurons in the live animal while presenting visual stimuli, we established that different parts of their retinas, looking at different parts of the visual world, do different things.
This multi-faceted view makes perfect sense for zebrafish as that's how colour is distributed in their natural habitat. In their natural visual world, most colour information is on the ground and the horizon but above them the objects of most interest are dark silhouettes, so colour vision here is rather pointless."
The study is the first in-depth physiological description of any vertebrate's retinal setup for colour vision that uses "4 input colours" which includes a large proportion of non-mammal species such as most birds, reptiles, amphibians and fish. By comparison humans only use three and mice, dogs and horses only two.
The researchers say little is understood on how colour vision based on four or more spectral inputs works at a neuronal level but their paper, should help pave the way for further discoveries in this field. The team custom-built a hyperspectral scanner that allowed them to capture the full spectrum of light in the zebrafish natural world at each pixel including for UV vision.
The study found that zebrafish, who during larval and juvenile life stages live mostly in shallow, low current pockets on the sides of streams and rice paddies, only seem to use their colour vision repertoire for looking down and along the horizon, use colour-blind circuits for looking straight up and extremely sensitive ultraviolet vision for looking forward and upwards.
The zebrafish has made a supreme evolutionary effort to develop this superior vision, with about half of all its neurons inside the eyes making up nearly a quarter of their total body volume and requiring substantial metabolic investment. Similar ratios on a human being would mean eyes around the size of a large grapefruit which would require an optic nerve the width of an arm.
Dr Baden said: "Clearly, animals like zebrafish use specialised strategies to better navigate their natural environment by adjusting their eyes to look out for different things in different parts of their visual field. In contrast, technology has not really caught up with these types of ideas. For example, most standard camera systems still "blindly" use the same type of light detection and compression across an entire image even if half the image shows bright blue sky and the other half the overgrown and shadowed ground."
Neil Vowles | EurekAlert!
'Flamenco dancing' molecule could lead to better-protecting sunscreen
18.10.2019 | University of Warwick
Synthetic cells make long-distance calls
17.10.2019 | Rice University
A very special kind of light is emitted by tungsten diselenide layers. The reason for this has been unclear. Now an explanation has been found at TU Wien (Vienna)
It is an exotic phenomenon that nobody was able to explain for years: when energy is supplied to a thin layer of the material tungsten diselenide, it begins to...
Researchers at Ludwig-Maximilians-Universitaet (LMU) in Munich have explored the initial consequences of the interaction of light with molecules on the surface of nanoscopic aerosols.
The nanocosmos is constantly in motion. All natural processes are ultimately determined by the interplay between radiation and matter. Light strikes particles...
Particles that are mere nanometers in size are at the forefront of scientific research today. They come in many different shapes: rods, spheres, cubes, vesicles, S-shaped worms and even donut-like rings. What makes them worthy of scientific study is that, being so tiny, they exhibit quantum mechanical properties not possible with larger objects.
Researchers at the Center for Nanoscale Materials (CNM), a U.S. Department of Energy (DOE) Office of Science User Facility located at DOE's Argonne National...
A new research project at the TH Mittelhessen focusses on the development of a novel light weight design concept for leisure boats and yachts. Professor Stephan Marzi from the THM Institute of Mechanics and Materials collaborates with Krake Catamarane, which is a shipyard located in Apolda, Thuringia.
The project is set up in an international cooperation with Professor Anders Biel from Karlstad University in Sweden and the Swedish company Lamera from...
Superconductivity has fascinated scientists for many years since it offers the potential to revolutionize current technologies. Materials only become superconductors - meaning that electrons can travel in them with no resistance - at very low temperatures. These days, this unique zero resistance superconductivity is commonly found in a number of technologies, such as magnetic resonance imaging (MRI).
Future technologies, however, will harness the total synchrony of electronic behavior in superconductors - a property called the phase. There is currently a...
02.10.2019 | Event News
02.10.2019 | Event News
19.09.2019 | Event News
18.10.2019 | Power and Electrical Engineering
18.10.2019 | Medical Engineering
18.10.2019 | Physics and Astronomy