The most important life sector 10 top-level creation (2)

Eyes — Graham Lawton

They appear in the light of evolution, but between a are therefore always changed life community rules. Before the advent of the eyes, more kind and gentle life, lazily in the ocean of slow software worms ruled. Eyes of creation presage a more brutal, cruel, replete with competitive world. Visual make animals become active predators as possible, it's evolutionary arms race changed planet.

Some of the earliest eyes appear to 5.43 billion years ago – at the beginning of the Cambrian – called Laidley-worm (Redlichia) of Trilobites in the group. Their eyes are compound eye, similar to modern insects, perhaps by a photographic point of evolution. Them in the fossil record of appearance unexpectedly visible — 5.44 billion years ago, the ancestors of the Trilobites have eyes yet.

In the magical million years happened? eyes must simply too complex and not suddenly appear? not so, according to Sweden's Lund University Dan-Eric Nilsson, he calculated a photosensitive cell composition spots only need half a million years to evolution as a compound.

"Eyes of evolutionary arms race change the planet"

It is not to say that the difference is negligible. Photosensitive cells form the spots and perhaps as far back as the prevailing before the Cambrian, it can let early animals perceive light and perception of the direction of the light. This degradation of sensory organs are still being jellyfish, flat worms and other life in the darkness of the original population use, clearly, better than nothing. But they are not on the eyes. Real eyes need some very thing – a focused light for imaging lens. Oxford University zoologists Andrew Parker said: "If you suddenly get the lens, the effect will rise from 1% to 100%. ”

Dragonfly eye

Trilobite is not the only occasionally gets this invention of the animal. Biologists believe that although genetics evidence the existence of a common eye animal ancestors, but eyes have evolved independently for many times. In any case, trilobite is eye animals first.

Eyes makes a difference in how! in early blindness, vision that is super. Trilobite eyes, making it the oldest active carnivores, they can find and follow a food, have never had the animals are able to do so. At the same time, it is expected that their prey object changed confrontational evolution. Only millions of years, the eyes become commonplace, animal survival struggle more proactive, wearing a defensive armor. The evolution of the outbreak is now known as the Cambrian explosion.

However, the vision is not widespread. 37 multicellular animals door, only 6 door evolved eyes, after all, you focus on it before the eyes might not look is a great innovation. With vision 6 door animal (including our own, chordata, and arthropods and molluscs) is the planet number extremely rich, widespread and successful animal life.

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