Tuesday, September 28, 2010

Trilobite Eyes-Anything but Primitive

Evolution's "first" known compound eye is far more complicated than the eyes of any vertebrates. How could that be ?

Selections from The Mystery of Trilobite Evolution, by Jerry Bergman

Marko’s summary: Trilobites supposedly evolved half a billion years ago as some of the simplest of creatures.  Yet there eyes are anything but primitive - they are among the most complex eyes known! The "real surprise" for evolutionists is that the "basic lens designs" of trilobite eyes were engineered "with such ingenuity." If you want an answer, don't go Back in Time, go Back to God!

(These selections by Marko Malyj are of the article published in Creation Research Society Quarterly Journal, Volume 47, Number 1, Summer, 2010, to appear at http://www.creationresearch.org/crsq/abstracts/Abstracts47-1.htm).

The Trilobite Eye

The trilobite eye is the first known eye. Trilobites possessed the first known "compound" (multi-lensed) eye design type (specifically the diopter apparatus) that has been preserved in detail in the fossil record.
Trilobites often lived in the very deep (thus, very dark) sea bottom. The eye lens was designed specifically to function in low-light water environments. To do this, trilobites "possessed the most sophisticated eye lenses ever produced," and their vision may actually have been superior to modern living animals (Shawver, 1974, p. 72).

The trilobite eye is as advanced as many of the most modern eyes known. Marine biologist Richard Ellis called the compound trilobite eye, a system containing hundreds of lenses, "far more complicated than the eyes of any vertebrates" (Ellis, 2001, p. 7). The once misnamed "simple primitive" trilobite eye is now known to be an incredibly well-designed, complex optical-chemical system.

A compound eye is constructed from a large array of separate eye optical elements called ommatidia. Each ommatidia was pointed in a different direction to allow the trilobite to simultaneously see in front, on each side, and behind, giving it a panoramic view of the world (Fortey et al., 2004). A network of neurons then translated the many optical images picked up by the compound eye photoreceptors into a single composite picture. This eye design is found today in insects and crustaceans (Levi-Setti, 1993).

The Three Basic Trilobite Eye Designs

 A large amount of variety exists in both the body and the eye design of the estimated 5,000 different trilobite genera. Three basic designs exist.

The Holochroal variety was both the most common and the most complex design. It consisted of thousands of small hexagonal-shaped lenses that functioned together as a unit.

The Schizochroal eye had fewer and larger biconvex lenses that were set in a turret-like arrangement, separated by an intrascleral membrane. It is found only in the Phacopida trilobite order. It is a "visual system quite different from any other eye that has ever appeared in the animal kingdom" (Levi-Setti, 1993, p.43, see also Fortey et al., 2004, p.449). This eye appears fully formed in the fossil record during the late Cambrian period.


The Abathochroal eye resembled the schizochroal, except that it did not have interlensral membranes between individual lenses.

The Trilobite Eye Lens

Trilobote eyes were usually hexagon shaped, but some used square, elongated clear calcite prisms (Fortey et al., 2000). The result was a design that had a huge advantage in low light. The lens used the spherical aplanatic design that largely eliminated the spherical aberration problem, the distortion caused by the lens shape (Fortey et al., 2004). According to Levi-Setti (1993, p.54):

The discovery of this optical doublet comes as somewhat of a shock - that trilobites developed and used such device half a billion years ago makes the shock even greater. And a final discovery - that the refracting interface between the two lens elements in a trilobite's eye was designed in accordance with optical constructions worked out by Descartes and Huygens in the mid-17th century - borders on sheer science fiction. (emphasis added)

Acidiphorus had holochroal eyes
Lack of evidence for trilobite eye evolution is especially problematic for Darwin's theory. After decades of new fossil discoveries by many researchers, no transitional fossils exist for their origins. In short, "trilobites are both complex and diverse when they appear in the lower Cambrian." (Black, 1988, p. 158).

Trilobite eyes, which are among the most complex eyes known, appear abruptly and very early in the fossil record. The trilobite eye optics were anything but primitive and would have required an enormous amount of time to evolve, and there are no documented ancestral precursors. As Levi-Setti (1993, p. 54) concluded, the "real surprise" is that the "basic lens designs" of trilobite eyes were engineered "with such ingenuity."

This evidence contradicts Darwin's (1859) prediction that the earliest eyes should be primitive and that a large number of transitional forms proving eye evolution from simple to complex would be found in the fossil record.

References (selected)
Black, R. 1988. The Elements of Palaeontology. 2nd Edition. Cambridge University Press, Cambridge, UK.
Darwin, C. 1859. The Origin of Species. John Murray, London, UK.
Ellis, R. 2001. Aquagenesis: The Origin and Evolution of Life in the Sea. Viking. New York, NY.
Fortey, R.A, R.M. Owens, D.E.G. Briggs and M.A. Wills. 2000. Trilobite! Eyewitness to Evolution. Knopf, New York, NY.
Fortey, R.A, R.M. Owens, D.E.G. Briggs and M.A. Wills. 2004. The lifestyles of the trilobites: these denizens of the Paleozoic Era seas were surprisingly diverse. American Scientist 92:446-453.

Levi-Setti, R. 1993. Trilobites. University of Chicago Press, Chicago IL.
Shawver, L.J. 1974. Trilobite eyes: an impressive feat of early evolution. Science News 105:72-73.

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