--->Exilement
"...you're seriously asking for observable proof of life's origins billions of years ago? There's a reason evolution is a theory. It involves a scientific interpretation of evidence in a way that agrees with all other evidence and anything else we know to be true."
You're right. Evolution is still a theory because people believe in it. Evidence will be interpreted differently according to ones presuppositions. Mine creation, so I will see things from my point of view, and you evolution so you will see things from your point of view.
---> Exilement
"Also evolution does not dictate that genomes should be more complex as time passes, so stop using that as an argument. It's false."
Again, you are right. It doesn't, but it has to. For us to have gotten here through evolution we would have to have become much much more complex.
--->
""Genes don't just pop into existence, completely functional and useful to the organism from day one. Or even if they might (I don't know of any examples) it's not how evolution works.""
I never thought that and please forgive me if I implied it. Evolution is believed to occur through much trial and error.
---> Exilement
"Either explain how the theory is inherently flawed, or give an alternative explanation to trichromacy's evolution through neofunctionalization of a duplicated photospin gene, which is exactly the sort of evidence you've asked from us."
I have opted for the former because I do not have a phd in biology. Still though, I will try. It didn't evolve. It was created from the beginning. (Mine was easier to say, and mine doesn't THINK it can be scientifically proved. Also, as far as that citation you gave... wow. Please, something in English. Also, its complexity reminded me of something.)
(I apologize for posting this much but I liked all of it and couldn't bear to cut it up.)
"The evolution of the eye has always been a dilemma for evolutionists from Darwin’s time to the present. Although Darwin, Richard Dawkins and other evolutionists have tried to explain how an eye could evolve, their solutions are clearly unsatisfactory. Many kinds of eyes exist, but no progression of eye designs from simple to complex can be produced in the natural or fossil world. Furthermore, the simplest ‘eye’, the eyespot, is not an eye but pigmented cells used for phototaxis; yet even it requires an enormously complex mechanism in order to function as a vision system.
The compound eye of an insect
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Figure 1. The compound eye of an insect. Note that the eye consists of hundreds or more separate eyes which, in some ways is more complex than the human eye. (After Mitchell et al.).48
The concept of irreducible complexity (IC) has become an important tool in intelligent design theory. One of the best examples of IC is the design of the animal eye. Eyes are critical because, for the ‘vast majority of animals’, vision is their ‘most important link to the world’.1 Darwin vividly recognized the problem of eye evolution and the serious impediment that it was for his theory. In his words,
‘To suppose that the eye, with all its inimitable contrivance for adjusting the focus to different distances, for admitting different amounts of light, and for the correction of spherical and chromatic aberration, could have been formed by natural selection, seems, I freely confess, absurd in the highest possible degree.’2
Nonetheless, Darwin felt the seemingly insurmountable problem of the evolution of what he called an organ of ‘extreme perfection and complication’ could be solved.2 He included a three-page proposal of intermediate stages through which eyes might have evolved via gradual steps.3 These stages included the following:
photosensitive cell
aggregates of pigment cells without a nerve
an optic nerve surrounded by pigment cells and covered by translucent skin
pigment cells forming a small depression and then a deeper depression
the skin over the depression gradually taking a lens shape
evolution of muscles that allow the lens to adjust.
These stages in living animals are believed to constitute major evidence for the evolution of the eye.4 Isaak claims that all of these steps are viable because all of them exist in animals living today:
‘The increments between these steps are slight and may be broken down into even smaller increments. Natural selection should, under many circumstances, favor the increments. Since eyes do not fossilize well, we do not know that the development of the eye followed exactly that path, but we certainly cannot claim that no path exists.’5
University of Chicago biology Professor Jerry Coyne wrote that human
‘ … eyes did not suddenly appear as full-fledged camera eyes, but evolved from simpler eyes, having fewer components, in ancestral species. Darwin brilliantly addressed this argument by surveying existing species to see if one could find functional but less complex eyes that not only were useful, but also could be strung together into a hypothetical sequence showing how a camera eye might evolve. If this could be done—and it can—then the argument for irreducible complexity vanishes, for the eyes of existing species are obviously useful, and each step in the hypothetical sequence could thus evolve by natural selection.’6
The dominant theory was outlined by Dennett, who concluded that all eye evolution requires is a
‘ … rare accident giving one lucky animal a mutation that improves its vision over that of its siblings; if this improvement helps it to have more offspring than its rivals, this gives evolution an opportunity to raise the bar and ratchet up the design of the eye by one mindless step. And since these lucky improvements accumulate—this was Darwin’s insight—eyes can automatically get better and better and better, without any intelligent designer.’7
Others are not so confident. Melnick concluded that the eye is a marvel and that ‘its immense complexity and diversity in nature, as well as its beauty and perfection in so many different creatures of the world, defies explanation even by macroevolution’s most ardent supporters.’8 This paper explores these conflicting views.
Evolution of the eye
The oldest eye in the fossil record, that of a trilobite, is a very complex faceted compound eye that ‘dates’ back to the Cambrian, conventionally dated about 540 million years ago.
Advanced vision appears almost at the very beginning of the fossil record. The oldest eye in the fossil record, that of a trilobite, is a very complex faceted compound eye that ‘dates’ back to the Cambrian, conventionally dated about 540 million years ago.9,10 The fossil evidence shows that from the beginning of the fossil record eyes are very complex, highly developed structures. We also have ‘living fossils’, animals that have remained virtually unchanged since very early in history. University of Salford biologist, Laurence R. Croft, wrote that the ‘precise origin of the vertebrate eye is still a mystery. The fascinating thing about the evolution of the eye is its apparent sudden appearance.’11 Specifically, the fossils show that vision originated ‘in the early Cambrian’, which Darwinists put at ‘some 530 million years ago’.12
Furthermore, although the ‘Cambrian animals were not the same species as exist today … nearly all the modern phyla had rapidly come into existence, fully equipped with eyes as far as can be told from the fossils’ and during the Cambrian explosion ‘something remarkable seems to have happened … a rich fauna of macroscopic animals evolved, and many of them had large eyes.’12 Sir Steward Duke-Elder, the preeminent ophthalmologist at the time of his death in 1979, acknowledged the sudden appearance of the perfected vertebrate eye, noting:
[The] precise origin of the vertebrate eye is still a mystery. The fascinating thing about the evolution of the eye is its apparent sudden appearance.—Laurence Croft, University of Salford
‘The curious thing, however, about the evolution of the vertebrate eye is the apparent suddenness of its appearance and the elaboration of its structures in its earliest known stages. There is no long evolutionary story as we have seen among invertebrate eyes, whereby an intracellular organelle passes into a unicellular and then a multicellular eye, attaining by trial and error, along different routes an ever-increasing degree of complexity. Within the vertebrate phylum the eye shows no progress of increasing differentiation and perfection as is seen in the brain, the ear, the heart and most other organs. In its essentials the eye of a fish is as complex and fully developed as that of a bird or man [emphasis added].’13
Biochemical studies have shown that the human lens contains
‘ … proteins similar to those found in the cyclostomes (hagfishes and lampreys) that are the living descendants of the Agnatha, which originated the vertebrates about 450 million years ago. Thus these studies have confirmed the view that the vertebrate eye, and in particular the lens, has changed very little during the course of evolution.’14
Evidence for eye evolution from living animals
Only about a third of all animal phyla contain species with proper eyes, another third contain species with light-sensitive organs only, and a third have no means of light detection, although many can detect heat.15 Nonetheless, of those animals with eyes, both vertebrates and most invertebrates, an enormous variety of eye designs, placement and sizes exists.10 The eyeball diameter ranges from less then a tenth of a millimetre in certain water fleas to 370 mm in the giant squid.16 Eye placement also varies, ranging from the common binocular vision employed by most mammals to the movable eye on each side of the head used by many lizards.
The number of eyes in one animal can also vary from none to eight. In spiders alone the number ranges from zero to eight, always existing in pairs of two. Some eyes contain both a lens and a retina-like structure in a single cell.17 A complex telephoto lens was identified in the chameleon in 1995. The reason why so many designs exist is because eyes must serve very different life forms that live in very different environments. Animals live in the ground, inside of other animals, in the air, on land, in salt water and in fresh water. Furthermore, animals range in size from a water flea to a whale.
Mean numbers of myelinated fibres in the optic nerve of selected vertebrates.
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Table 1. Mean numbers of myelinated fibres in the optic nerve of selected vertebrates. Note the enormous difference within each category. For example birds range from 408 to 988 thousand, mammals from 7 thousand to 1.21 million. (From Cousins50).
Although many kinds of very different eyes are known, no direct evidence exists to support the evolution of the eye and its accessory structures. Furthermore, much evidence contradicts such evolutionary beliefs. For example, note in table 1 that the number of myelinated fibres in the optic nerve does not correlate with putative evolutionary development. A pigeon has almost as many fibres as a human. Many birds, such as the eagle and hawk, have excellent vision yet have half as many fibres as a domestic pig.
Another example is visual pigments. The presumably highest, most evolved form of life, the higher primates, have only two cone photoreceptors, blue and green, but birds have a total of six pigments: four cone pigments plus pinopsin (a pineal photoreceptive molecule) and rhodopsin for black and white vision.12,18 Put another way, chickens, humans and mice all have the rhodopsin pigment; mice in addition have blue and green; humans have blue, green, and red; and birds have these three pigments plus violet and pinopsin. For every colour that humans perceive, birds can see very distinct multiple colours, including ultraviolet light. Birds use infrared light (which we sense as heat) for night vision, allowing them to rapidly visualize their young in a dense, dark tree.
The possibility of classifying eyes in living animals from simple to complex—simple types existing in simple animals and complex types in complex animals (which we will show cannot be done)—does not provide evidence for an evolutionary relationship. A primary problem is that this attempt is based only on eye characteristics as they presently exist. Historical eye evolution cannot be proven by listing a series of existing eyes from simple to complex and then arguing that the complex evolved from the simple because evolution requires that all existing eyes have an equally long evolutionary history.
According to neo-Darwinism, the simplest modern eye in living animals has had the same amount of time and evolutionary history as the most complex eye because life began about 3.5 billion years ago and all life today evolved from this point in history. Although Darwinists argue that many of these eyes are evolutionary dead ends, this would require an admission that these modern ‘simple’ eyes are only analogues or ‘similar’ to putative past ancestral eyes (to more complex modern types), which reduces their value as evidence.
Darwinists need to determine the eye designs from which existing eyes have actually descended, one from the other, over time. Duke-Elder and Darwin (1872) before him were unable to do this, yet they offered their list of eyes of varying complexity as evidence of evolution. Cousins wrote:
‘ … the crucial importance of this requirement to the theory of evolution was fully understood by Darwin, who stated that, in searching for the gradations through which an organ in any species has been perfected, we ought to look at its lineal progenitors. Indeed we ought; though he himself could not do so. It is deceptive to the reader to create a seriation beginning with eye spots as seen in unicellular organisms and call them, as does Duke-Elder (1958), the earliest stage of evolution.’19
Croft concluded that the claim that we can line up eyes in an evolutionary sequence from very simple to very complex is false because research on the developmental history of the eye in widely differing species finds
‘ … it remarkably similar. Indeed the basic features of the eye in different vertebrates are very much the same despite great variations in their mode of life and adaptation to habitat. Furthermore, unlike other organs such as the heart, there is no long evolutionary history with the eye. In essence the eye of a newt is as complex and fully developed as that of a man.’11
Sinclair also concluded that vertebrates and most invertebrates, including insects and cephalopods (molluscs, including octopuses and squid), all have eyes with common visual elements, including ‘a similar photoreceptor design’, yet have a marked ‘dissimilarity of their appearance’.10
The source of the design and evolution of the eye, Darwinists postulate, was a series of beneficial mutations that had to occur in appropriate unison in order to produce the set of structures required for eyes to function. The new mutation set, Darwinists argue, resulted in a superior structure compared to the old one, and this new and better eye improved the animals’ ability to compete against other forms of life. Some of the many problems with this conclusion were noted by Grassé in his discussion of Myrmelion (ant lion) anatomy:
‘Have you ever seen a mutation simultaneously affecting two separate components of the body and producing structures that fit one another precisely? … have you ever beheld three, four or five simultaneous mutations with matching structures producing coordinating effects? … These are vital questions that demand an answer. There is no way of getting around them, or evading the issue. Every biologist who wants to know the truth must answer them, or be considered a sectarian and not a scientist. In science there is no “cause” to be defended, only truth to be discovered. How many chance occurrences would it take to build this extraordinary creature [Myrmelion formicarius]’?20
An organ that did not aid the animal’s survival would use scarce energy, nutrients and b
