Viruses: Living or Non-Living ???
There is much debate whether viruses are considered alive or inanimate, with the conclusion based largely on which definition of "life" one holds viruses up against. One thing for certain is that they are parasites that depend on host cells to become active and 'life-like'. Originally seen as poisons, then as life-forms, then biological chemicals, viruses today are considered as being in a gray area between living and nonliving: they cannot replicate on their own but can do so in truly living cells and can also affect the behavior of their hosts profoundly. The table below lists the characteristics that suggest viruses are not living vs. those that suggest they are living:
|
|
As viruses do not share many of the traditional characteristics of living things, many scientists do not consider them alive, period. However, if one defines life from the bottom up, from the simplest forms capable of displaying the most essential attributes of a living thing - it is argued that the only real criterion for life is the ability to replicate, definitely applicable to viruses. Some scientists consider viruses to be ‘living’ chemicals. Thus they seem to be non-living inert entities until they enter a host cell and become, essentially, alive. Considering this controversy, Life is perhaps better understood not as a reductionist, black and white category, but rather a nuanced, highly complex state arising from various factors, creating a spectrum that would see viruses placed somewhere not fully alive but also "more than inert matter: they verge on life.”
Next, we will examine further some further intriguing qualities of viruses.
Next, we will examine further some further intriguing qualities of viruses.