A natureza dos vírus sob a teoria do gene egoísta de Dawkins

Abstract

The COVID-19 outbreak brought up a long-standing debate about the nature of viruses. Based on strict concepts of life, they do not grow, have metabolism and internal homeostasis, or replicate without a host, so they could not be alive. The discovery of giant viruses revives their role in early evolution. They exhibit greater complexity and carry an extensive genome, depending less on the host. Viruses must have evolved from more complex organisms and lost their genes, reducing to the essentials. According to Dawkins’ selfish gene theory, the evolution by natural selection acts on specific genes as a unit of selection. This replicator uses transient ‘vehicles’ in favor of its multiplication, and the selfish aspect keeps genetic traits passing on. From natural selection perspective, the replicators or viral genes which least replicate will decrease in frequency. The fact that they kept it simple in structure does not imply the inert status. Boundaries between living vs. nonliving are a continuum, this classification may be a philosophical and semantics debate rather than scientific. This review aims to gather information about the origin of viruses and the relationship with primordial life through a narrative review of the literature. Through the comprehension aboutthe ubiquity and evolutionary aspects of viruses, it is possible to reach a general understanding that they can be classified as living beings, as they express hereditary information and evolve through natural selection.