Tag: limestone

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Learn from Trilobite Eyes

Learn from Trilobite EyesOne of the more interesting fossils you will ever find is a trilobite. This three-lobed ocean-going creature was an arthropod related to insects and crabs. Its closest living relative is probably the horseshoe crab, although behaviorally, it may have been more like a lobster or crayfish. Today we find beautifully preserved trilobite specimens in rocks dating back to the beginning of life on Earth. What can we learn from trilobite eyes?

We can study and learn from trilobite eyes because they were made of the mineral calcite. Calcite is the same mineral that makes up limestone, so it is quite hard and efficiently preserved. In its purest form, it is perfectly clear. Calcite possesses what scientists call a double index of refraction. Because of the arrangement of atoms in calcite, light arriving at one angle passes undisturbed while light at another angle will be split into two beams.

In addition to being made of calcite, the trilobite eye was made up of a honeycomb of hexagons. There could be several thousand hexagons in the eye arranged so that light from any angle would be refracted into the animal’s eye. If it came perpendicularly, the light would go straight to the back of the eye. If it came at an angle, the double index of refraction would still bring the light to the back of the eye. There was a small wall between the hexagons so that light from the hexagons did not overlap each other. When arthropods grow, they molt their outside layer, and the new larger layer hardens. The eye material would add hexagons as the animal got larger.

This kind of eye is similar to the eye of a housefly. Like flies, trilobites would have been especially good at detecting motion. They also would not have a problem with near-sightedness or far-sightedness. Something an inch away or a mile away would both be in focus at the same time.

There is one vision problem the trilobite would have. It’s called spherical aberration. The thickness of the materials in each hexagonal lens would not be the same, and that difference could distort the image. In the trilobite eye, this problem was solved by magnesium atoms added to the calcite in a way that corrects the aberration. Modern opticians do this with what they call a doublet lens.

Scientists have observed other special features in various species of trilobites. They have found some eyeless trilobites that probably lived in areas with no light, such as very deep in the ocean. Other eyes were mounted in ball-like structures that could move. Still others were positioned so that the animals could bury themselves in the sand like a stingray while their eyes could still look out for food or enemies.

There are many lessons we can learn from trilobite eyes. The incredible complexity is a tribute to God’s wisdom and design. In this case, the complexity is of particular interest because trilobites were some of the first animals to live on this planet. That fact presents a problem for those who say complexity is a result of evolutionary forces over a very long time. Trilobites already had a sophisticated visual system when they first appeared in the fossil record in the Cambrian period 500 million years ago. Darwinistic models cannot explain the trilobite eye, but the God of the Bible can.
— John N. Clayton © 2019

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Relying On Ignorance

Relying on Ignorance of Grand Canyon Formation
We often hear from young people who have been taught something in a Bible class or sermon or a religious publication or video that they know cannot be true. Many creationists and creationist groups lack training in the fields in which they claim to be experts, and they are relying on ignorance of their hearers. When smart young people hear something they know is incorrect, it gives them a reason to reject the church and perhaps reject God’s existence.

A classic example of this is shown in explanations of the Grand Canyon. Many writers try to explain away the formation of the Grand Canyon by saying that the Flood of Noah did it. They say the Flood formed the Canyon in a short time just a few thousand years ago. They claim that the Flood laid down the sediments, and when the water swept off the land, it carved the Grand Canyon.

As an Earth Science teacher in the public schools in South Bend, Indiana, I taught young people about petrology — the study of rocks. Knowing how rocks were formed enabled scientists to find resources such as copper, oil, marble, iron, and certain gems. We can now synthesize some of these materials by copying the methods by which they were formed in the Earth’s past. Relying on ignorance would not allow us to find or synthesize these materials.

We know that the deposition of materials and subsequent erosion by the Flood did not form the Grand Canyon. The dominant rock in the Grand Canyon is limestone. Children taking Earth Science courses learn that limestone is a chemical precipitate. Quiet waters produce it over a long time. Most of us know about rock candy in which a solution of sugar crystallizes to create the candy. Limestone produced by a similar process, as is halite, dolomite, and gypsum. These are chemically precipitated rocks, never deposited in moving water.

A recent headline in a creationist journal reads, “Rapid Limestone Deposits Match the Flood.” A young person told me that she didn’t want to hear anything else from the Church because the statements in the journal were clearly not true. She doubted anything the Church said was true as a result. She also pointed out other problems. The Canyon is not just one rock type. It has alternating layers of different materials produced by different climates and processes. There are desert-produced sandstones, conglomerates which are produced by running streams, salt deposits produced by evaporation, and lavas that flowed across the top of the rock layers below them and were not injected as sills.

There is a huge burden on us to know what we are talking about. We must be as accurate as we can in understanding what the evidence shows. The general public is ignorant of most of these things and will not call an error to our attention. However, young people today are better educated in scientific facts, and we must not be relying on ignorance to expect our explanations to go unchallenged.
–John N. Clayton © 2018

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Modern Misconceptions About the Flood

Modern Misconceptions about the Flood
Perhaps the most argued event in the Old Testament is the flood of Noah described in Genesis. For the past several days we have been examining some of the questions people have. Today we will look at two modern misconceptions about the flood.

Did the Ark come to rest on Mount Ararat? The answer to that question is “no!” Genesis 8:4 says that the Ark came to rest “upon the mountains of Ararat” which is not modern day Mount Ararat. This is of little interest except that the claims of some people that they found the Ark on modern-day Mount Ararat are clearly erroneous.

Was the Grand Canyon caused by the flood laying down strata and then carving the canyon by erosion? The answer to that question is also “no.” The rocks in the canyon are not of one deposition and are not flood strata. Floods leave a tangled mess of debris. The majority of rocks in the Grand Canyon are limestone which is a chemically precipitated rock. The limestone is interspersed with conglomerate, shale, desert deposits of sandstone, and some volcanic deposits. A flood would produce none of those except shale.

Do fossils in the Grand Canyon verify the flood? No, a flood produces a tangled mess of all kinds of remains of plants and animals. The rock layers in the Canyon have different animals at different layers. Each animal or plant grouping is a function of the environment in which they lived. That is not what a flood would do.

The question is not whether the flood happened, but rather what a flood would do and what remains from the flood. There are dozens of flood layers in the stratigraphy all over the American southwest, but which one might be related to Noah’s flood cannot be determined.

There are many modern misconceptions about the flood of Noah. The flood did not create the Grand Canyon. The rocks and fossils prove that. No one has found Noah’s Ark. The claims of someone finding the Ark have always turned out to be erroneous. We need to test every Spirit and not be sold a bill of goods by religious groups trying to back up their beliefs by claiming to have found the fossils of giants, an ark, or some other claimed artifact of the flood of Noah.
–John N. Clayton © 2018
We have a discussion of the flood in our video series program # 27 available on our doesgodexist.TV website. You can also look up information on the flood by doing a word search on our doesgodexist.org website search engine.

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Grand Canyon Formation

Grand Canyon Formation
As we told you before, this is the week of the 2018 Canyonlands Tour. We mentioned the plaque at the Grand Canyon watchtower with the verse from Psalms. Today, we would like to share with you a video segment from a previous field trip to the Grand Canyon. In the video, geologist and teacher John Clayton uses the diagram shown above as he describes the layers of the Canyon and the various processes that formed them. The Grand Canyon formation processes are complex and involve God’s work through natural forces over a vast span of time.
–Roland Earnst © 2018