So duplicate genes are not macroevolution's secret laboratory. Furthermore, everyone agrees that harmful mutations appear many, many times more often than mutations needed for new construction ever could. Over those millions of years, slightly harmful mutations that are hidden, or not destructive enough for natural selection to remove, would also quietly accumulate. This would produce creatures loaded up with highly polluted genes. Survival of the barely functional? We do not find this either because cells have mechanisms that maintain the original design of a creature within its variation boundaries, and minimize the accumulation of mutations. These include:
- A proofreading system that catches almost all errors
- A mismatch repair system to back up the proofreading system
- Photoreactivation (light repair)
- Removal of methyl or ethyl groups by O6 - methylguanine methyltransferase
- Base excision repair
- Nucleotide excision repair
- Double-strand DNA break repair
- Recombination repair
- Error-prone bypass36
Harmful mutations happen constantly. Without repair mechanisms, life would be very short indeed and might not even get started because mutations often lead to disease, deformity, or death. So even the earliest, "simple" creatures in the evolutionist's primeval soup or tree of life would have needed a sophisticated repair system. But the mechanisms not only remove harmful mutations from DNA, they would also remove mutations that evolutionists believe build new parts. The evolutionist is stuck with imagining the evolution of mechanisms that prevent evolution, all the way back to the very origin of life.
Genome size
Scientists have found that the number of genes a creature has is not a good measure of how complex it is. For example, the human genome is 23 times larger than the fruit fly genome (3.2 billion base pairs versus 137 million), yet humans have only about 2 times the number of protein coding genes (almost 25,000 versus 13,000 according to Human Genome Project Information). Yeast has about 6,000 genes.
| | The tiny water flea Daphnia pulex has more genes than humans do; up to 39,000 at last count.Water Flea Boasts Whopper Gene Count. 5 June 2009. Science, Vol. 324, No. 5932, p. 1252. |
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| | So does the pea aphid Acyrthosiphon pisum , with 34,600.Water Flea Boasts Whopper Gene Count. 5 June 2009. Science, Vol. 324, No. 5932, p. 1252. |
The main reason for biological complexity must be in the rest of the genome, the non-coding part, which determines how those genes are used.
Junk DNA
Only a small portion of a creature's DNA is protein-coding genes (around 1.5% in humans). In the 1970s, evolutionists began calling the rest of it "junk DNA", saying this collection of useless evolutionary debris showed there was no intelligent design involved. Decades later, researchers are finding that the "junk" does vital work. Some of this DNA plays a role in turning genes on and off at the right moments in a developing embryo24. Other bits separate coding and regulating sections, like punctuation marks in writing, so that DNA is not a long run-on sentence25. Other bits called Alu elements, found only in primates, can be spliced in or out during RNA processing to make different versions of the same gene.26 The "junk" label discouraged research into this part of the genome for many years; who would want to waste their time studying it?
Networks
The living things of the world are extremely varied and intricately made, yet the theory of evolution has always been about simplicity: once upon a time, some chemicals assembled, began to make copies of themselves, and little by little changed into all life forms. Evolutionists like to use the words "simply" and "merely" when telling their stories to the public. There is certainly nothing complicated about the idea of mutation-natural selection. However, by the year 2000, research had reached a point where a new branch of biology was needed: Systems Biology. Discoveries in this field are the exact opposite of merely simple. Biological systems are vastly more complex than anyone could imagine. Some wonder if we will ever fully understand them.
A small section of a biological system in an organism, displayed as a 3D network
"To make sense of the genome, systems biologists think in terms of networks. If two kinds of proteins or other biological molecules interact, they are connected on the network." "These network diagrams... show how individual pathways crisscross to form a tangled web. Each protein in a pathway can interact with molecules in other pathways, sometimes dozens of them." Additionally, "systems biologists produce complex maps of how genes and proteins interact, and these maps help scientists analyze results from drug screening." "Cells 'talk' to each other by passing chemical signals back and forth. They also sense their physical surroundings through proteins on their surfaces called integrins. All these cues serve to orient the cells in the body and inform them about how to behave so that they cooperate with the rest of the cells in the tissue." "The cells are not complete by themselves. They need signals from outside," says Mina J. Bissell of Lawrence Berkeley National Laboratory. "The unit of function literally is the tissue."-- Patrick Barry. April 5, 2008. You, in a dish: cultured human cells could put lab animals out of work for chemical and drug testing. Science News, Vol. 173, No. 14, pp. 218-220.
"The interesting point coming out of all these studies is how complex these systems are; the different feedback loops and how they cross-regulate each other and adapt to perturbations are only just becoming apparent. The simple pathway models are a gross oversimplification of what is actually happening", says Mike Tyers, a systems biologist at the University of Edinburgh, UK.-- Blow, Nathan. 16 July 2009. Untangling the protein web. Nature, Vol. 460, pp. 415-418.
This is a map of how the genes in a cell of the budding yeast Saccharomyces cerevisiaeinteract with one another. Each color shows what a group of genes does. Genes in these functional networks interact with other genes throughout the cell; a cell of yeast.
Costanzo, Micha