According to a new study published in the online journal Evolutionary Biology, BMC, these fish seem to have benefited from depth vision and were able to view their new environment in full color.
When the prehistoric fish first came onto land, what did they see? According to a new study published in the online journal Evolutionary Biology, BMC, these fish seem to have benefited from depth vision and were able to view their new environment in full color.
A team led by Helena Bayles from the School of Biomedical Sciences at the University of Queensland in Brisbane, Australia, analyzed the retinas of ottersal lungfish (Neoceratodus forsteri) which are considered to be the closest living creatures to the first terrestrial vertebrates. The researchers compared these retinas to those of fish and other amphibians.
The DNA of five genes that control visual colors in lungfish revealed that they are more common in quadrupedal vertebrates than in fish. Although lungfish breathe through gills like most fish, they can also breathe air directly if the water quality is poor.
Lungfish were previously considered to have poor eyesight due to their small eyes, little ability for spatial vision, their slow behavior in captivity and their ability to locate their prey using electrical receptors. The fish of this species lives in shallow and bright pools of fresh water similar to the environments from which the first land creatures probably evolved.
This led the researchers to study the genes expressed in these fish to trace the development of vision in the ancestors of the four-limbed vertebrates. The research paves the way for behavioral work with lungfish to see if they can distinguish between objects based on their color.
The genus Neoceratodus, of which N. forsteri is the only surviving species, is found in the fossil record from the Lower Cretaceous era, 135 million years ago, and therefore N. forsteri probably competes for the title of the oldest vertebrate," says Bayles. "His visual system may represent the closest evolutionary design that represents a period immediately before the appearance of continental sand dunes in the Devonian era."
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For commenter number 4.
It's not just mistakes, sometimes there are certain needs, which prepare genetic modification. See in hot countries, people there are browner, or in cold countries, people have more fats.
If you take someone from a cold country, and give them a normal diet, they will get fat, because it's their genetics, even if it came from an external source.
All the respondents have a mistake.
Evolution is not planned and it is not a certain process.
It's a mess that happens during genetics so only the strong survive.
I look forward to your response.
You require the lungfish to have two mutations for both lung enhancement and color vision. Since he will only get his survival by developing the lungs with or without color vision, it seems to me that the mutation to improve the lungs will have the dominant effect. Only then will the lungfish, whose lungs are already properly constructed, be able to "indulge" in mutations that will improve its color vision.
That's how I see things.
In any case, I am now going to rest and regain strength for the lecture I am going to give at the observatory in Givatayim today on the subject of the simple universe.
I have a pleasant rest
Sabdarmish Yehuda
Partially agree with the words of Sabdarmish Yehuda as a possibility for criticism - although it seems to me that the development of evidence does not interfere with the development of other things at the same time. Moreover, the development of sight, it seems to me, is perhaps the first organ that must be developed as soon as the conditions are ripe to go ashore.
In addition, I quote from the article the phrase "evolutionary planning" which is problematic.
It should be understood that those who think that those historical lungfish have not undergone any evolution since the Lower Cretaceous, are wrong and misleading.
The lungfish coming to land were obliged to use all their evolutionary "effort" for the purpose of going to land and not to invest in developing color vision as well. At a later stage they could develop color vision, if they did not have it in the water.
Only a DNA test, which is not possible because of the long time that has passed since the Cretaceous, can only show whether they saw in color or not.
Have a good day
Sabdarmish Yehuda