Another evolution question?

Question

Okay so I can see that there is evidence for microevolution, survival of the fittest and all but what about macroevolution, I mean how on earth would an eye evolve?! what kind of mutation would lead to something as complex as an eye arising, or a kidney. Surely eyes didn't evolve gradually over time?!

Answer 1

Through natural selection, different types of eyes have emerged in evolutionary history -- and the human eye isn't even the best one, from some standpoints. Because blood vessels run across the surface of the retina instead of beneath it, it's easy for the vessels to proliferate or leak and impair vision. So, the evolution theorists say, the anti-evolution argument that life was created by an "intelligent designer" doesn't hold water: If God or some other omnipotent force was responsible for the human eye, it was something of a botched design.

Biologists use the range of less complex light sensitive structures that exist in living species today to hypothesize the various evolutionary stages eyes may have gone through.

Here's how some scientists think some eyes may have evolved: The simple light-sensitive spot on the skin of some ancestral creature gave it some tiny survival advantage, perhaps allowing it to evade a predator. Random changes then created a depression in the light-sensitive patch, a deepening pit that made "vision" a little sharper. At the same time, the pit's opening gradually narrowed, so light entered through a small aperture, like a pinhole camera.

Every change had to confer a survival advantage, no matter how slight. Eventually, the light-sensitive spot evolved into a retina, the layer of cells and pigment at the back of the human eye. Over time a lens formed at the front of the eye. It could have arisen as a double-layered transparent tissue containing increasing amounts of liquid that gave it the convex curvature of the human eye.

In fact, eyes corresponding to every stage in this sequence have been found in existing living species. The existence of this range of less complex light-sensitive structures supports scientists' hypotheses about how complex eyes like ours could evolve. The first animals with anything resembling an eye lived about 550 million years ago. And, according to one scientist's calculations, only 364,000 years would have been needed for a camera-like eye to evolve from a light-sensitive patch.
I have provided the source for this, and much more information on the evolution of the eye below.
I hope this helped.

Answer 2

There really is no difference between microevolution and macroevolution. Add up microevolution for a while and you get macroevolution.

With something complex like the eye, it does not evolve at once. Rather, it comes in stages. We know this because we actually see the different stages in different animals. Animals with the ability to detect light may have a better survival advantage. The ability to detect where the light is coming from is even better, which is why a spherical hole forms in the population over time.

Let me find a video that can it explain it much better than me! Irreducible complexity is a popular argument against evolution, but it is easily dismantled.

Answer 3

I see that, in you, lies the essence of Creationists. You could
have Googled the phrase "evolution of the eye" and got the answer you need, but you decided to argue your point in ignorance.
If eyes were just created, why are there 6 basic types of them, such as we have, compound, those found in squid etc, when really there is no significant benefit in the difference. The reason is that they developed at different times, under different environmental influences, over a long period of time. Why are dogs and cows colour blind? Why can birds see colour, sometimes much better than humans? It is all a matter of need, and a matter of millions of years.

Microevolution is a term Creationists use to concede to the exceedingly obvious - that evolution is evident if you look for it. They then, like yourself, go on to deny macroevolution, as if the two are different fundamental concepts.
There is no difference between microevolution and macroevolution, apart from the amount of time over which it is measured.
It is all evolution - adaptation over time.

Edit: Teachercade, below, is the other pillar of the Creationist debate, - "if we evolved from apes, why are there still apes?" All I can say is that I despair the ignorance of some sections of society. Modern apes and humans evolved from a common ancestor, millions of years ago. Humans did not evolve from modern apes any more than tigers evolved from lions.
.

Answer 4

Silly girl, education is for people like you. We have a whole range of eye types at differing levels of complexity though out the organismic world. Not even " old earth creationists " are using the eye as a counter to evolutionary theory any more. Your argument is a classic " argument from ignorance " and quite tiresome, I have sent you here when you posed a similar question in biology. this is your last chance to become educated. I think these people have 29 evidences for what you call " macroevolution. "

http://www.talkorigins.org

Answer 5

Surely, they did.

Pick up a biology text. There are plenty of examples of intermediate light sensitive organs.

The whole concept of "intelligent design" is just another attempt at limiting the abilities of God to those of man. We have studied the eye, understand it's function and have copied it. Same with the kidney.

It wasn't some intelligent designer that sat in front of a drawing board and noodled out some spiffy biological organs to slap together to make a human being. It was a "divine" designer who created a universe and set into motion the properties of mass - energy such that gravitation and electro-magnetism and nuclear binding energy result in a process such as evolution which, in turn, has resulted in human beings (as planned).

How?

If we knew, God wouldn't be much of a God, would She?

Answer 6

Sure. There are all kinds of worms with "eye spots", patches of flesh which are photo-sensitive.

There are microbes that are light-philic (light loving) and light phobic (light avoiding).

The kidney is, in some ways, more interesting evolutionarily. It started out with relative simple physiochemical functionality, probably little more than a sieve, and has grown more and more complex depending on the organism.

Answer 7

over simply needs...

eye: seeing helps organisms hunt/survive better

They do evolve over time. For example you might not see it as an eye but maybe it was some kind of sensory mechanism that helped to detect. Overtime it took on the shape of an eye.

kidney: helps the body fight diseases

Answer 8

Surely they did.

Surely - an intelligent "Designer"/"Creator" would not have created an eye containing a blindspot that occurs WITHIN the eye (and must be compensated for by binocular vision) itself caused BY the optic nerve!

Answer 9

huge_f_in_frog's link was the one I was going to use, but here's another:

http://en.wikipedia.org/wiki/Evolution_of_the_eye

And another:

http://www.blackwellpublishing.com/ridley/a-z/Evolution_of_the_eye.asp

And another:

http://www.simonyi.ox.ac.uk/dawkins/WorldOfDawkins-archive/Dawkins/Work/Articles/1995-06-16peepers.shtml

And there's more, but you get the drift. Eyes weren't just put together as an afterthought to creation...they developed over millions of years, with each new part adding something to the whole that wasn't there before. It really isn't too big of a stretch to believe, once you get over the "__________(insert the supernatural being of your choice) did it" sentimentality.

Edit: Sorry, I meant huge_f_in_dork

Answer 10

Surely they did!
From a light-sensitive cell, to a patch of light sensitive cells, to light sensitive cells beneath a protective covering...
Not only that, but this happened several times!