A gene responsible for the entry and exit of pigeons and the shaper of vision in humans is also responsible for the reception of light in hydras, creatures that have existed for 600 million years
Through the study of the hydra, that famous laboratory animal, which belongs to an ancient group of marine creatures that still thrives, scientists at the University of California at Santa Barbara were able to discover and understand the origin of human vision. The findings were published in the journal Proceedings of the British Royal Society of Biology.
The hydras are simple animals, and together with the jellyfish make up the system cnidaria. The Sanidarians first appeared 600 million years ago.
"We determined which generic gate, or ion channel, in hydra is involved in light sensitivity," said senior researcher Todd O'Kalley, from the Department of Ecology, Evolution and Marine Biology at the University of California, Santa Barbara. "This is the same gate where human vision is used."
Oakley explained that there are many genes involved in vision, and that there is an ion channel gene responsible for initiating the neural pulse of vision. This gene controls the entry and exit of pigeons, meaning it actually acts as a gate.
The gene, known as opsin, takes part in the act of vision among many invertebrates and is responsible for various ways of vision in animals such as flies. Insect sight appeared later than the sight mechanism found in hydra and invertebrates.
"This work builds on and adds to previous research in my lab, and continues to challenge the common misconception that evolution is a continuous march of progress, with humans at the top," Oakley said. "Instead, evolution explains how all creatures - including man - are a complex mixture of old and new characteristics."
David Palachecki, who received his PhD on work done in Oakley's department, is the project's principal investigator. He is currently a postdoctoral fellow at the University of California, Davis. Along with him, Caitlin Fong from the University of California at Santa Barbara also signed the article.
For information on the website of the University of California at Santa Barbara
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general question:
When the information from the light receptors in the retina goes to the brain and is processed there - how does it become an "image"?
I understand the idea of the need for light sensors so that the various organs of the body can act accordingly and orient themselves in space and so that the eyes can react back accordingly - but... where is the "image" "saved"?
In any discussion about science that you participate in
Love this site!
Where else can you find a non-scientific debate about science? Hi to all of us!
survival of the least inadequate
I also thought that man is at the peak of "evolution" in the wrong order, no need to make a fuss about it
Big deal . In the end it's all a matter of settings.
And that doesn't sound too complex to you?
The article is too concise for my taste... It is not clear what is the innovation and what is the importance of the 600 million years, etc.
By the way, heh heh:
Have you heard of photosynthesis?
Heb Heb:
You didn't see because you didn't want to see.
After all, it is clear from your first question that you are a creationist of some kind who is trying again to sell us non-discharges.
Here is a quote from what I referred you to:
Several type 1 opsins, such as proteo-, halo- and bacteriorhodopsin, are used by various bacterial groups to harvest energy from light to fix carbon using a non-chlorophyll-based pathway..
I didn't see there that the opsin can be used alone. It's some minimal processing to differentiate between light and dark.
Heb Heb:
Light receptors can begin their journey as a tool for absorbing energy from the environment - even without any control system whatsoever.
http://en.wikipedia.org/wiki/Opsin
I don't know what you call a control system, but even in relatively primitive bacteria, a more sophisticated phenomenon is discernible than just absorbing energy, and they can move towards the light because the absorbed light affects the movement of their rod (some are attracted to it and some run away from it).
http://en.wikipedia.org/wiki/Phototaxis
Does anyone know what survival benefit there was in photoreceptors, without any minimal processing mechanism? As far as I know, photoreceptors are not effective by themselves.
lion:
Yes.
They talk about how the eye evolved several times (and in fact took on very different forms here and there) but when talking about the eye, talking about the vitreous structure with the lenses. From the article it appears that this structure evolved (several times) only after light-receiving cells evolved in a common ancestor.
The author of the article is wrong.
It is written "And God saw that it was good", and it is known that God existed long before 600 million years.
To 2
Humans are not at the top of the animal world physically. Humans have a very difficult time surviving in the environment, we don't have nails or claws, we have sensitive and delicate skin, we are barely able to walk barefoot in nature... Only thanks to human technology, humans were able to spread across the globe and establish thriving populations. And this technology is indeed a product of our developed intelligence (Za, of those who managed to use this intelligence, and were not busy all their lives with hallucinations about visible and invisible beings).
To the best of my knowledge, vision in arthropods, octopuses and squids of various kinds and vertebrates - each developed separately and on a different evolutionary path. Is what the article states that those vision mechanisms that developed separately were all based on the mechanism of a hydra-like creature as described in the article?
Response 1 does not seem serious and according to what the writer wrote in response 5 it is indeed not so and there is no doubt that he knows that there is no chain and there is no peak for evolution. Everyone that exists today is in the same place on the evolutionary tree as every other organism that exists today.
By the way, cnidaria in Hebrew "stings"
Illusory resemblance:
For you surely.
No person who understands evolution thinks that evolution is a continuous march of progress, with humans at the top. Just nobody! This is a claim that only mindless people like you make.
When he talks about the "common error" he is talking about the error of people like you which are, unfortunately, common.
Now a religion versus evolution debate will develop here.
Cynicism is a form of humor that is too high for some people
My response refers to 1.
And response to 2: From a physical point of view, there are many creatures that are superior to humans in survival capacity - see spiders for example.
He basically says what you say, that it's hard to argue that humans are the pinnacle of evolution when people like you exist.
Humans are at the top perhaps today, not throughout evolution, and until a more advanced creature is discovered. Man is the peak in two respects - mentally (unless you bring an example of a more intelligent creature) and physically - while each creature is only suitable for its environment, man can live in extremely diverse environments.
What is meant by the sentence: "and continues to challenge the common error that evolution is a continuous march of progress, with humans at the top" He disagrees with evolution?!!?!
He is considered a serious scientist
He should be denounced and crucified on the altar of conservative science!!!!