Darwin’s Surprise

The article is titled “Darwin’s Surprise” mainly because Darwin would have been surprised to learn that his theory of evolution involving a shared common ancestor would be supported by the fact that “humans are descended from viruses as well as from apes”. These viruses, which are known as endogenous retroviruses, play a role in evolution by infecting the DNA of a species and proceeding to become a part of that species. The article states that “eight per cent, however, is composed of broken and disabled retroviruses, which, millions of years ago, managed to embed themselves in the DNA of our ancestors” in regards to the human genome. The fact that they are broken and disabled suggests that they are “junk DNA”, since they can cause no harm, and that these remnants are helpful in understanding their relation to human evolution. Darwin might have also been surprised to suggest that natural selection would have found the endogenous viruses to be advantageous in order to survive and remain in the human genome because of the relation to his theory of evolution.

The parts of the article that I found to be most surprising were learning that our genome contained remnants of viruses that were possessed by a common ancestor and the whole suggestion by Thierry Heidmann with the involvement of endogenous retroviruses and the placenta. These viruses had to have provided some benefit in order for it to be passed down through generations although it involves embedding in DNA, which can be destructive. The process of bringing dead viruses back to life seems surprising as well, as this can be done by piecing together broken parts after figuring out how they were originally aligned. The placenta, which is crucial to mammals and provides protection for the fetus, might not have been able to be developed without endogenous viruses as they provided changes so that human beings do not lay eggs.

In regards to the role viruses have played in evolution, the article suggests that endogenous viruses became a part of a species when they infected the DNA and were passed on from a common ancestor. These viral fragments “have been defeated by evolution”, which means that they serve no purpose as it can no longer function efficiently although they remain within us. Even though some are still able to produce proteins, these remnants have not been found to be harmful. In fact, these viruses have proven to be protecting and cause development for the important placenta in mammals. These ideas presented in the article have definitely changed my understanding of viruses as I now no longer perceive them as just harmful parasites. Viruses usually have a negative connotation attached to them, as they usually cause diseases and deaths. With further studies in paleovirology (“which seeks to better understand the impact of modern diseases by studying the genetic history  of ancient viruses”), viruses can be proven to be helpful in understanding how to treat diseases.

I believe that science should “revive” dead viruses because it should be beneficial for scientific studies in finding treatments for diseases. Although there’s the idea of this process going completely wrong and providing more harm than help, I think that the pros outnumber the cons. The article states that “the experiment could provide vital clues about how viruses like H.I.V. work” when discussing Thierry Heidmann and his revival of a dead virus. Also, there are far worse and more dangerous viruses than those that they have tested, so as long as everything is experimented under moderation, the revival of dead viruses would ultimately be beneficial for science.

Advertisements
This entry was posted in Evolution, Viruses. Bookmark the permalink.

4 Responses to Darwin’s Surprise

  1. rishyg7 says:

    It certainly is amazing that eukaryotic cells could have figured out which genes are viral and which ones are the cell’s genes. I also think Darwin would have been very surprised to hear that some viruses, which target and destroy the basic building blocks of life, can be advantageous to the survival of an organism. Although it may be unrelated, viruses proving to be advantageous reminds me of the way smallpox was eradicated by using a less harmful type of a similar virus, cowpox. Organisms that had been exposed to cowpox had gained resistance to smallpox which was a devastating virus. I agree with Sam, by studying dead viruses we can find treatments for many diseases. The most important thing to remember when studying viruses is that they can mutate quickly. This is what makes viruses so dangerous but also very fascinating, in a very short amount of time a virus can be completely different.

  2. elbroderick says:

    I definitely agree that we should revive “dead” viruses. Not only does it allow us to study and understand how viruses like HIV work, it also may help us find a cure. Reviving these viruses could help scientists to expand their research into animals such as rats of mice. The article mentions that HIV and SIV do not infect small mammals, and so there really aren’t any affordable or ethical ways to study these retroviruses in depth with a host.

  3. AreebA says:

    Your analysis of the relation between Darwin’s theory of evolution and the information form the article is spot on. Darwin had already been considering there to be a common ancestor between all organisms. He studied the effects the environment had on the overall fitness of an organism; to know that smaller cells such as viruses can have such effects as to change the overall development of an organism would certainly “surprise” Darwin. Not to mention the fact that the viruses can be embedded into the human genome as “junk DNA” as you said.
    Like you, my opinion of viruses has also changed. I usually associate viruses such as the common cold to be bad to the overall health of an organism. However, this article sheds a new light on viruses. The fact that eight percent of the human genome contains viral DNA should already reveal that not all viruses are harmful to an organism.

  4. RichardK says:

    I agree that science should revive dead viruses. The pros definitely outweigh the cons, as you said. Reviving a virus that has been defeated in history to learn how it functions might give us the knowledge to tackle modern viruses such as HIV. If the revived virus were to escape a lab, any damage it does probably would not compare to the damage that modern viruses like HIV already causes right now. In a strictly scientific view, any loss is negligible and a necessary sacrifice for the greater good. Though since these dead viruses became instinct because mankind has defeated them, I wonder if we are immune to them still to this day, since their DNA is incorporated into ours. It might be the case since when PtERV was revived and tested, unaltered human cells seemed to still be immune to it.

Leave a Reply

Please log in using one of these methods to post your comment:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s