Horizontal Gene transfer, another ad hoc explanation
http://reasonandscience.heavenforum.org/t1614-horizontal-gene-transfer-another-ad-hoc-explanation
The evidence of jumping transposons (=a segment of DNA that can become integrated at many different sites along a chromosome)
Common Ancestry
1. In recent years, evolutionary biologists have increasingly used DNA sequences to construct evolutionary trees. Researchers find transposons particularly suitable for this endeavor.
2. When evolutionary biologists propose evolutionary relationships, they rely on the principle that organisms with shared DNA sequences arise from a common ancestor.
3. But other mechanisms exist that can introduce the identical DNA sequences. Horizontal gene transfer (HGT) is one.
Horizontal Gene Transfer (HGT) Mimics Common Ancestry
4. HGT refers to any process that transfers genetic material to another organism without the recipient being the offspring of the donor. HGT occurs frequently in bacteria and archaea. A consequence of this process is that, from an evolutionary vantage point, microbes that are unrelated through common descent will possess the same DNA sequences. In other words, HGT has the same genetic signature as common ancestry.
5. Until recently, most biologists thought that HGT was confined to microbes. Yet, in the last couple of years, researchers have uncovered evidence for horizontal gene transfer in higher plants and animals, which they think is mediated by viruses and single-celled pathogens transmitted from species to species via an insect vector. Because of transposons’ mobility within genomes, they readily take part in HGT events.
6. As with microbes, HGT in higher plants and animals obfuscates the ability of evolutionary biologists to use transposons to establish reliable evolutionary relationships.
7. For example, researchers discovered that when they use two different classes of transposons, called BovB and Spin elements, to build evolutionary trees, absurd relationships resulted. Cows were more closely related to snakes than to elephants and geckos more closely related to horses than to other lizards.
8. Many people regard shared DNA sequences as the best evidence for evolution and common descent. But as this cutting-edge research demonstrates, other mechanisms, such as horizontal gene transfer, can introduce the same DNA sequences in organisms, thus, masquerading as evidence for common descent of HGT.
9. As science continues to unmask understanding of these processes, the case for common design strengthens.
10. The ability of transposons to jump around or move from the genome of one organism into that of another is an evidence for a common designer of all species who is God.
11. God exists.
Shared Genes Undercut Evolutionary Tree
In a study published in Current Biology, Vanderbilt University evolutionary biologists Antonis Rokas and Jason Slot examined two different species of mold that have distinct DNA and appearances. Strangely, however, these molds share a sequence of 60 thousand base pairs, lined up in the same order.
This sequence contains a cluster of genes that, when translated by its cell into proteins, forms an assembly line to manufacture a particular chemical used for defense. Since the chances are nil that the exact same sequence of 60 thousand bases twice evolved through any random approach, the researchers assumed that the whole cluster "jumped" from one fungus to the other.
Other researchers have observed similar "gene jumping" across species in microbes, which are equipped with tools that sample and incorporate DNA from their environments into their super-small, single cells. But no known mechanism for this process—called "horizontal gene transfer" or "lateral gene transfer (LGT)"—has been characterized for eukaryotes (cells with nuclei and specialized structures), let alone for multicellular eukaryotes such as fungi, slugs, or four-footed animals.
Horizontal gene transfer in evolution: facts and challenges
it is a disputed point whether horizontal gene transfer precludes the reconstruction of phylogenetic relationships in the microbial world. In any case, horizontal gene transfer is not a canonical or typical evolutionary mechanism. Thus, I agree with other authors that there is a need for a new paradigm in evolution that includes horizontal gene transfer among other neo-Darwinian and non-neo-Darwinian mechanisms.
http://reasonandscience.heavenforum.org/t1614-horizontal-gene-transfer-another-ad-hoc-explanation
The evidence of jumping transposons (=a segment of DNA that can become integrated at many different sites along a chromosome)
Common Ancestry
1. In recent years, evolutionary biologists have increasingly used DNA sequences to construct evolutionary trees. Researchers find transposons particularly suitable for this endeavor.
2. When evolutionary biologists propose evolutionary relationships, they rely on the principle that organisms with shared DNA sequences arise from a common ancestor.
3. But other mechanisms exist that can introduce the identical DNA sequences. Horizontal gene transfer (HGT) is one.
Horizontal Gene Transfer (HGT) Mimics Common Ancestry
4. HGT refers to any process that transfers genetic material to another organism without the recipient being the offspring of the donor. HGT occurs frequently in bacteria and archaea. A consequence of this process is that, from an evolutionary vantage point, microbes that are unrelated through common descent will possess the same DNA sequences. In other words, HGT has the same genetic signature as common ancestry.
5. Until recently, most biologists thought that HGT was confined to microbes. Yet, in the last couple of years, researchers have uncovered evidence for horizontal gene transfer in higher plants and animals, which they think is mediated by viruses and single-celled pathogens transmitted from species to species via an insect vector. Because of transposons’ mobility within genomes, they readily take part in HGT events.
6. As with microbes, HGT in higher plants and animals obfuscates the ability of evolutionary biologists to use transposons to establish reliable evolutionary relationships.
7. For example, researchers discovered that when they use two different classes of transposons, called BovB and Spin elements, to build evolutionary trees, absurd relationships resulted. Cows were more closely related to snakes than to elephants and geckos more closely related to horses than to other lizards.
8. Many people regard shared DNA sequences as the best evidence for evolution and common descent. But as this cutting-edge research demonstrates, other mechanisms, such as horizontal gene transfer, can introduce the same DNA sequences in organisms, thus, masquerading as evidence for common descent of HGT.
9. As science continues to unmask understanding of these processes, the case for common design strengthens.
10. The ability of transposons to jump around or move from the genome of one organism into that of another is an evidence for a common designer of all species who is God.
11. God exists.
Shared Genes Undercut Evolutionary Tree
In a study published in Current Biology, Vanderbilt University evolutionary biologists Antonis Rokas and Jason Slot examined two different species of mold that have distinct DNA and appearances. Strangely, however, these molds share a sequence of 60 thousand base pairs, lined up in the same order.
This sequence contains a cluster of genes that, when translated by its cell into proteins, forms an assembly line to manufacture a particular chemical used for defense. Since the chances are nil that the exact same sequence of 60 thousand bases twice evolved through any random approach, the researchers assumed that the whole cluster "jumped" from one fungus to the other.
Other researchers have observed similar "gene jumping" across species in microbes, which are equipped with tools that sample and incorporate DNA from their environments into their super-small, single cells. But no known mechanism for this process—called "horizontal gene transfer" or "lateral gene transfer (LGT)"—has been characterized for eukaryotes (cells with nuclei and specialized structures), let alone for multicellular eukaryotes such as fungi, slugs, or four-footed animals.
Horizontal gene transfer in evolution: facts and challenges
it is a disputed point whether horizontal gene transfer precludes the reconstruction of phylogenetic relationships in the microbial world. In any case, horizontal gene transfer is not a canonical or typical evolutionary mechanism. Thus, I agree with other authors that there is a need for a new paradigm in evolution that includes horizontal gene transfer among other neo-Darwinian and non-neo-Darwinian mechanisms.
