Changes

Evolution has actually been witnessed within a human lifetime. Bacteria, as they procreate very quickly (I think the fastest is a new generation every 20 mins)they go through evolutionary processes much faster than other lifeforms on earth. I am sure all of you are aware of the new MRSA bacteria which is resistant to antibiotics. This bacteria seemed to have sprung up from nowehere and very rapidly all over the globe. How else could you explain this without using evolution? It seems to me that it is obvious that this bacteria (remembering that it is essentially the same bacteria only antibiotic resistant) has evolved to be resistant to our drugs. Following on from that, if non resistant bacteria died out to be replaced by resistant bacteria (as Survival of the Fittest would suggest) would evolution skeptics rethink their posistion?

Evolution has actually been witnessed within a human lifetime. Bacteria, as they procreate very quickly (I think the fastest is a new generation every 20 mins)they go through evolutionary processes much faster than other lifeforms on earth. I am sure all of you are aware of the new MRSA bacteria which is resistant to antibiotics. This bacteria seemed to have sprung up from nowehere and very rapidly all over the globe. How else could you explain this without using evolution? It seems to me that it is obvious that this bacteria (remembering that it is essentially the same bacteria only antibiotic resistant) has evolved to be resistant to our drugs. Following on from that, if non resistant bacteria died out to be replaced by resistant bacteria (as Survival of the Fittest would suggest) would evolution skeptics rethink their posistion?

[[MetcalfeM]]

MetcalfeM

:: The bacteria are still bacteria, aren't they?  Yet evolution is supposed to change living things into quite different living things (e.g. dinosaurs into birds).  Furthermore, you haven't demonstrated that the resistance to antibiotics is due to ''new genetic information''.  All such resistances have been already existing in a subset of the population, have been transferred from other bacteria, or have been due to a mutation which ''decreases'' genetic information.  [[User:Philip J. Rayment|Philip J. Rayment]] 20:04, 6 January 2008 (EST)

:: The bacteria are still bacteria, aren't they?  Yet evolution is supposed to change living things into quite different living things (e.g. dinosaurs into birds).  Furthermore, you haven't demonstrated that the resistance to antibiotics is due to ''new genetic information''.  All such resistances have been already existing in a subset of the population, have been transferred from other bacteria, or have been due to a mutation which ''decreases'' genetic information.  [[User:Philip J. Rayment|Philip J. Rayment]] 20:04, 6 January 2008 (EST)

:What you describe is absolutely true, and everyone here knows that I agree with you. However, what you have described is a form of microevolution. The resistant bacteria either acquired a mutation that rendered it resistant, or there was a transfer of plasmid DNA from another bacterium, or perhaps a bacteriophage infected the strain and altered its genome. In other words, it was a genetic transformation. [[User:Wisdom89|Wisdom89]] 21:56, 2 January 2008 (EST)

:What you describe is absolutely true, and everyone here knows that I agree with you. However, what you have described is a form of microevolution. The resistant bacteria either acquired a mutation that rendered it resistant, or there was a transfer of plasmid DNA from another bacterium, or perhaps a bacteriophage infected the strain and altered its genome. In other words, it was a genetic transformation. [[User:Wisdom89|Wisdom89]] 21:56, 2 January 2008 (EST)

Now, stop me if I am wrong here but microevolution effects populations on a small scale. Say, within a single population that shares a gene pool. An analogy could be a population of birds that inhabit a section of forest. Some sort of environmental factor such as Wisdom89 pointed out above produces a microevolution in this population of birds but is not a large scale of macroevolution. While this is correct in every sense there is something which I find interesting. MRSA is not the only super bug out there and wasn't the first. While this maybe microevolution, the scale is certainly very large and involves several different types of bacteria. MRSA was first spotted in the UK and the strain was swiftly located in hospitals around the world. What is interesting is this MRSA was originally found in hospitals, not so much throughout the community, and mainly in first world hospitals also. A bacterium would find environments in first world hospitals fairly standardized, wherever in the world, and the same antibiotics have been used. All of sudden in countries everywhere and within a short period of time were experiencing cases of MRSA. This bug is very hard to transmit (as in a human to human contagion) and would certainly be difficult for MRSA to have a chain of infection running from the UK outwards so quickly. It looks like the species "turned on" its resistance worldwide as the species was facing the same antibiotics and environmental pressures worldwide. That is a large scale evolutionary change. [[MetcalfeM]]

Now, stop me if I am wrong here but microevolution effects populations on a small scale. Say, within a single population that shares a gene pool. An analogy could be a population of birds that inhabit a section of forest. Some sort of environmental factor such as Wisdom89 pointed out above produces a microevolution in this population of birds but is not a large scale of macroevolution. While this is correct in every sense there is something which I find interesting. MRSA is not the only super bug out there and wasn't the first. While this maybe microevolution, the scale is certainly very large and involves several different types of bacteria. MRSA was first spotted in the UK and the strain was swiftly located in hospitals around the world. What is interesting is this MRSA was originally found in hospitals, not so much throughout the community, and mainly in first world hospitals also. A bacterium would find environments in first world hospitals fairly standardized, wherever in the world, and the same antibiotics have been used. All of sudden in countries everywhere and within a short period of time were experiencing cases of MRSA. This bug is very hard to transmit (as in a human to human contagion) and would certainly be difficult for MRSA to have a chain of infection running from the UK outwards so quickly. It looks like the species "turned on" its resistance worldwide as the species was facing the same antibiotics and environmental pressures worldwide. That is a large scale evolutionary change. MetcalfeM

:You should add that without sexual reproduction, it becomes a bit more difficult to define a species, because it is typically defined as a population that can interbreed and produce fertile offspring. Unicellular organisms reproduce by cell division, and you'll need to look at other criteria based on for example morphology, or genetics. [[User:Order|Order]] 17:34, 3 January 2008 (EST)

:You should add that without sexual reproduction, it becomes a bit more difficult to define a species, because it is typically defined as a population that can interbreed and produce fertile offspring. Unicellular organisms reproduce by cell division, and you'll need to look at other criteria based on for example morphology, or genetics. [[User:Order|Order]] 17:34, 3 January 2008 (EST)

::Incidentally, this is also a problem with classifying creatures known only from fossils.  I believe that it's rather difficult for a fossil to mate with another fossil.  [[User:Philip J. Rayment|Philip J. Rayment]] 21:26, 6 January 2008 (EST)

::Incidentally, this is also a problem with classifying creatures known only from fossils.  I believe that it's rather difficult for a fossil to mate with another fossil.  [[User:Philip J. Rayment|Philip J. Rayment]] 21:26, 6 January 2008 (EST)