Scientists Report Doubts over Key Theory of Evolutionary Extinction

by Frank Sherwin, M.A.*

Researchers have recently “ruled out a hypothesis” that has been taught as dogma in schools, colleges and universities worldwide: the cause of the Permian extinction, allegedly “the mother of all mass extinctions.”

Geologists and paleontologists state in a recent article in Nature Geoscience that at the end of the Permian era—which they calculate occurred some 250 million years ago—“95 percent of marine species and 70 percent of land species were wiped out.” Called the “Great Dying” by some researchers, it is difficult not to think of a cataclysmic event, such as a global flood (Genesis 6 – 9), when reading of such massive destruction.

Regardless, evolutionary scientists have taught for decades that this Permian extinction event was precipitated by gradual oxygen starvation of the world’s oceans. This supposedly led to a massive die-out of marine life due to “clouds of hydrogen sulphide” rising from the seas.

Now many scientists are stymied as to what caused this devastating event, but Flood geologists have an idea: massive flooding, possible asteroid activity, and large-scale volcanism. History records such a catastrophic event in Genesis 7:11.

Indeed, many scientists are coming closer to the truth when they rule out clouds of hydrogen sulphide and look approvingly at “an impact, or series of impacts, by an asteroid.” Granted, this is not the Flood, but such bombardments probably did occur at this time. In fact, many geologists now agree with creation scientists that earth did experience a worldwide cataclysmic event. Take note of this shift from a position that does not fit the facts to a more reasonable scientific understanding—sudden cataclysm(s) such as asteroids or even a “fierce period of volcanism,” which happens to fit historical accounts found in the biblical record.

Of course, researchers in creation science continue to follow the evidence where it leads, and little by little, Darwinian scientists committed to evolutionary dogma are beginning to confirm what we’ve been stating all along.

Cataract Research: Genetic Defect Responsible For Small Eyes And Clouded Lens Discovered

ScienceDaily (Apr. 10, 2008) — The ocular lens belongs to the optical apparatus and focuses incidental beams of light onto the retina. Now, a research team led by Professor Dr. Jochen Graw of the Institute of Developmental Genetics, of the Helmholtz Zentrum München, has been able to decipher a genetic defect responsible for small eyes and an incomplete, clouded lens in the so-called Aey12 mouse mutants. These results lead to conclusions concerning cataracts in humans, because, in this case too, the lens loses its transparency.

The development of the eye in mammals (and this naturally includes humans) is an extraordinarily complex process beginning in an early embryonic phase. The same applies also to the formation in healthy eyes of elastic and transparent lenses, which focus light beams. With the aid of the ciliary muscles, the lens can change its degree of curvature and thus set itself on varied, far distant objects. As a result, a pin sharp image is created on the retina.
“As with humans, with mice too, the development of the lens starts with the formation of a spherical, hollow sac,” Graw says. “That is the lens vesicle, the cover of which is surrounded by the lens epithelium, composed of a layer of cells. The vesicle is then filled in with fiber cells. In the following course of development, additional fibers originate in the equator of the lens. These scale up the diameter of the lens: a process that lasts a lifetime.”
But not so with the Aey12 mouse mutants, which Graw’s eye researchers in the study group “Molecular Eye Development” have iknvestigated in detail. The animals of this line are distinguished by their unusually small eyes, a microphthalmia. Combined with cataracts, this dosorder is also known in humans and leads nearly always to blindness. With Aey12 mice, the early development of the eye lens is strongly affected. As the scientists in the current issue of the well-known, American journal in the field of ophthalmology, “Investigative Ophthalmology & Visual Sciences”, report, with the mutant mice, the growth of the fibers that fill up the body of the lenses, is completely blocked. “What remains is then a cloudy and functionless small lens sac,” Oliver Puk adds, the first author of the study. “The animals thereby lose their sight almost completely.”

As the scientists in the current study were able to show, the basis of the disease is a defect in a hitherto unknown gene. Genes are units of the hereditary DNA molecule that contains blueprints for proteins. Errors in the sequence of the gene building blocks can lead to proteins with limited or completely lost functions: and in this way, in the worst case, to serious diseases or development disorders. The Neuherberg eye researchers gave the name Gjf1 to the gene responsible for the alterations of the Aey12 mutant mice. It is a member of the Connexin family. “The genes belonging to this group get the information for the construction of channel proteins, which build the cell to cell connections,” Graw declares. “Such channels are of great importance for the interchange between cells: also, among other things, between the fiber cells of the developing eye lens itself.”

The scientists now speculate that through the newly discovered mutation, the structure of the Gjf1 channel protein is changed, and in this way the formation of the channel is hindered. But through this, the communication between the developing lens fibers would break down. Thus, it would be conceivable that signal molecules essential for the development of the lens are no longer exchanged, or only to a limited extent. In this scenario, faulty cell communication would be the cause of the development of the fibers stopping: and ultimately, of the cloudiness of the eye lens, which would otherwise be transparent.

This very phenomenon is also observed in cataracts in humans, a common disease, which appears mostly in the elderly: in Germany alone more than half a million operations are carried out annually, in which the cloudy and opaque lens is replaced with an implant. “Our results will surely also provide an insight into the origin of cataracts,” Graw adds. “Moreover, so far, there has not yet been any mutation in humans equivalent to Gjf1 gene of mice. But this will now change soon, for sure.”

Journal reference: Oliver Puk, Jana Löster, Claudia Dalke, Dian Soewarto, Helmut Fuchs, Birgit Budde, Peter Nürnberg, Eckhard Wolf, Martin Hrabé de Angelis, and Jochen Graw (2008): Mutation in a Novel Connexin-like Gene (GJF1) in the Mouse Affects Early Lens Development and Causes a Variable Small-Eye Phenotype. Investigative Ophthalmology & Visual Science, vol 49, pp 1525-1532

Adapted from materials provided by Helmholtz Zentrum München - German Research Center for Environmental Health.

Skulls Of Modern Humans And Ancient Neanderthals Evolved Differently Because Of Chance, Not Natural Selection

ScienceDaily (Mar. 20, 2008) — New research led by UC Davis anthropologist Tim Weaver adds to the evidence that chance, rather than natural selection, best explains why the skulls of modern humans and ancient Neanderthals evolved differently. The findings may alter how anthropologists think about human evolution.

Weaver's study appears in the March 17 issue of the Proceedings of the National Academy of Sciences. It builds on findings from a study he and his colleagues published last year in the Journal of Human Evolution, in which the team compared cranial measurements of 2,524 modern human skulls and 20 Neanderthal specimens. The researchers concluded that random genetic change, or genetic drift, most likely account for the cranial differences.
In their new study, Weaver and his colleagues crunched their fossil data using sophisticated mathematical models -- and calculated that Neanderthals and modern humans split about 370,000 years ago. The estimate is very close to estimates derived by other researchers who have dated the split based on clues from ancient Neanderthal and modern-day human DNA sequences.
The close correlation of the two estimates -- one based on studying bones, one based on studying genes -- demonstrates that the fossil record and analyses of DNA sequences give a consistent picture of human evolution during this time period.
"A take-home message may be that we should reconsider the idea that all morphological (physical) changes are due to natural selection, and instead consider that some of them may be due to genetic drift," Weaver said. "This may have interesting implications for our understanding of human evolution."
Weaver conducted the research with Charles Roseman, an anthropologist at the University of Illinois at Urbana-Champaign, and Chris Stringer, a paleontologist at the Natural History Museum in London.
Adapted from materials provided by University of California, Davis.

Fossil From Last Common Ancestor Of Neanderthals And Humans Found In Europe, 1.2 Million Years Old

ScienceDaily (Apr. 4, 2008) — University of Michigan researcher Josep M. Pares is part of a team that has discovered the oldest known remains of human ancestors in Western Europe.
The find shows that members of the genus Homo, to which modern humans belong, colonized the region much earlier than previously believed. Details of the discovery were published in the March 27 issue of the journal Nature.
The fossil—a small piece of jawbone with a few teeth—was found last year in a cave in the mountains of northern Spain, along with primitive stone tools and bones of animals that appear to have been butchered.
The team, led by Spanish researchers Juan Luis Arsuaga, José María Bermúdez de Castro and Eudald Carbonell, used three separate techniques (including paleomagnetic analyses performed by Pares) to determine that the fossil is about 1.2 million years old. That's 500,000 years older than the previous oldest known humanlike fossils from the area. The new find bolsters the view that Homo reached Europe not long after leaving Africa almost 2 million years ago.
"It seems probable that the first European population came from the region of the Near East, the true crossroads between Africa and Eurasia, and that it was related to the first demographic expansion out of Africa," said Pares, who is a research scientist in the U-M Department of Geological Sciences and program director of the newly created National Research Center on Human Evolution (CENIEH) in Burgos, Spain, with which most of the authors are affiliated.
The researchers tentatively classified the new fossil as an earlier example Homo antecessor (Pioneer Man), the species represented by the previous oldest fossils and thought to be the last common ancestor of Neanderthals and modern humans.
"This is a very significant advance toward a better understanding of the nature, age and protagonists of the first European human settlement," Pares said.
Adapted from materials provided by University of Michigan.

The Theory of Evolution

This theory really fascinate me! Why? It has been a very controversial subject ever since Charles Darwin proposed it to the Science World.

Are we really descent from lowly creature that evolved millions of years ago? Are we created by supernatural forces a few thousand years ago?

What is exactly a Theory of Evolution?
Darwin defined this term as "descent with modification." It is the change in a lineage of populations between generations. In general terms, biological evolution is the process of change by which new species develop from preexisting species over time; in genetic terms, evolution can be defined as any change in the frequency of alleles in populations of organisms from generation to generation.

When we talk about evolution there are two things that we should consider seriously; Natural Selection and Mutation.

Natural selection: The differential survival and reproduction of classes of organisms that differ from one another in one or more usually heritable characteristics. Through this process, the forms of organisms in a population that are best adapted to their local environment increase in frequency relative to less well-adapted forms over a number of generations. This difference in survival and reproduction is not due to chance.

Mutations: Changes in the genome (genetic constitution). There are quite a number of ways in which mutations can happen. They also differ in the way that they impact evolution.

Mutations which occur when the genome is copied during reproduction are known as vertical transfer mutations. They are called vertical transfer mutations because they are transferred from ancestor to descendent along vertical lines of descent. In the original work on population genetics it was assumed that all mutations were vertical transfer mutations.

Horizontal transfer mutations occur when DNA is moved from one organism to another. Horizontal transfer can be a major source of evolutionary novelty. It is important because new genes can be propagated much more rapidly by horizontal transfer than by vertical transfer. If evolution is depicted by the tree, vertical genetic movement is the transmission of genes down branches; horizontal genetic movement is the transmission of genes between the branches.
Intra-organism transfer mutations occur when genes or parts of genes move around within an organism.

Strictly speaking, hybrids (mating across species) are not mutants. In many groups of species, particularly among plants, genes are transferred from to one species to another via hybrids.

Types of mutations:

1. Point mutations
   The most common type of copying error is the point mutation. In this form of mutation the nucleotide at a site is replaced by a different nucleotide. When people talk about mutation rates they are usually talking about rates of point mutations.
   Effects of point mutations: Point mutations in junk DNA are common but have no effect. Sometimes point mutations in regulatory regions have no effect and sometimes they alter the expression of some genes.


2. Additions and deletions
   During copying a segment of DNA may be deleted or a new segment may be inserted. Typically this happens as a result of chromosome breakage or realignment. (See below.) Additions and deletions can also be produced by certain types of horizontal transfer.
   Effects of additions and deletions: If the length of the new or deleted segment is not a multiple of three the translation will be garbled after the point at which the insertion/deletion occurred because the frame reading is now misaligned. This is known as a frameshift mutation. In some genes there are segments that may be duplicated as a block. This is known as tandem duplication.


3. Chromosomal duplication
   Sometimes one or more chromosomes are duplicated during reproduction; the offspring get extra copies of those chromosomes.
   Effects of chromosomal duplication: Duplicating only one chromosome is generally disadvantageous; an example in human beings is Down's syndrome. Having multiple copies of all of the chromosomes is known as polyploidy. Polyploidy is rare in fungi and animals (although it does occur) and is common in plants. It has been estimated that 20-50% of all plant species arise as the result of polyploidy.
   Gene duplication is very common; it is important because it provides a way to evolve new capabilities while retaining the old capabilities. All intermediate stages can be found in nature, from a single gene with alternate alleles to nearly identical duplicated genes with slightly different functional alleles to gene families of evolutionarily related genes with different functionalities.


4. Chromosomal breakage and realignment
   During reproduction a chromosome may break into two pieces or two chromosomes may be joined together. A section may be moved from one part of the chromosome to another or may be flipped in orientation (inverted). This is the mechanism by which deletions, duplications and transpositions my occur.
   Effects of chromosomal breakage and realignment: Quite often these types of changes do not affect the viability of the organism (the genes are still there; they're just in different places) but, in sexually reproducing species, they may make it less likely for the organism to produce viable, fertile offspring.


5. Retroviruses
   Certain viruses have the ability to insert a copy of themselves into the genome of a host. The chemical that make this possible (reverse transcriptase) is widely used in genetic engineering.
   Effects of retroviruses: Usually this is a way for the virus to get the host to do the work of reproducing the virus. Sometimes, however, the inserted gene mutates and becomes a permanent part of the host organism's genome. Depending on the position of the viral DNA in the host genome, genes may be disrupted or their expression altered. When insertions occur in the germline of multicellular organisms, they can be passed on vertically.


6. Plasmids
   Plasmids are little pieces of circular DNA that are passed from bacterium to bacterium. Plasmids can be transferred across species lines.
   Effects of plasmid transfer: Plasmid transfer is an important way of spreading useful genes such as those which confer resistance to antibiotics. Plasmid transfer is an example of horizontal transfer.


7. Bacterial DNA exchange
   Bacteria can exchange DNA directly. They often do this in response to environmental stress.
   Effects of bacterial DNA exchange: Exchange is often fatal to one or both of the bacteria involved. Sometimes, however, one or both of the partners acquires genes which are essential for the current environment.


8. Higher level transfer
   Some parasites can pick up genetic material from one organism and carry it to the next. This has been observed in fruit flies in the wild.
   Effects of higher level transfer: When this happens novel alleles can spread much more rapidly through a species than they would for ordinary gene flow.


9. Symbiotic transfer
   When two organisms exist in a close symbiotic relationship one may "steal" genes from the other. The most notable example of this are mitochondria. In most organisms with mitochondria most of the original mitochondrial genes have moved from the mitochondria to the nuclear genome.
   Effects of symbiotic transfer: A major effect is that the symbiotic relationship changes from being optional to be obligatory.


10. Transposons
    Transposons are genes that can move from one place in the genome to another.
    Effects of transposons: Depending on the position of insertion, transposons can disrupt or alter the expression of host genes. In some species most mutations due to transposon insertion. For example, in Drosophila, 50-85% of mutations are due to transposon insertions.

In The Theory of Evolution, the mutation that suppose to have occurred are the beneficial or favorable mutation that are hereditary and together with forces of natural selection, our world is full of diverse and complex fauna and flora that evolved from simple common ancestor.

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