08 November 2025 Article

The Mysterious Origin of the Undefined, Deathly Creature-Virus

The Origin of Lifeforms.

In 1859, Charles Darwin shook the world with his nearest possible answer to the biggest unsolved puzzle of life- its origin.

The Revolutionary Theory of Evolution.

Evolution is a gradual process of biotic adaptation that accumulated for thousands, millions, or even billions of years, resulting in an entirely different species. Evolution’s pace and differentiation, besides time, depend on environmental factors that force creatures to adapt, such as temperature, food chains, biome, natural disasters, etc. Darwin suggested that an organism’s survival depends on its ability to adapt.

According to the latest theory development, life emerged from an environmental condition known as the Primordial Soup, 4 billion years ago. The formation of amino acid-the main substances of RNA and DNA took place there, further constructing the first life form of Earth.

Cyanobacteria, a microscopic blue-green algae capable of energy metabolism and reproduction, believed as the earliest known life form on Earth. They first appeared approximately 3.5 billion years ago, gifted with an amazing ability that drove evolution until you, who read this now.

Photosynthesis. The ability to convert photons into oxygen allowed them to reproduce and grow rapidly. Slowly but surely, they managed to form our ozone-based atmosphere, preventing the dangers of UV radiation, meteorites, solar storms, etc.

Thanks to them, our inhabitable planet transformed into a safe environment for life to grow and evolve for the next billions of years.

Evolution gave answers to biotic similarity and diversity at once. Millions of years from now, polar and grizzly bears may evolve into separate species. Who knows?? Even mighty scary dinosaurs have turned into chickens.

The Missing Link

The Missing Link

Darwin’s breakthrough theory encouraged biologists to search for proof. With genome analysis, they began to link interspecies evolution lineage through similar and extinct species.

However, scientists aren’t sure if they can apply the theory universally yet. For two centuries, research has shown several creatures with untraceable links; the creature’s genome code had successfully been translated, but its evolution lineage is yet unknown.

Scientists define this as “the missing link”. Octopus, for example, is labeled as an “alien” because of its weird and abnormal genetic code. According to https://octopus.org.nz/, octopus have 33.000 protein-coding genes, more than us with 20.000. They managed to consciously mutate their RNA, giving them new instructions. Some hypothesize octopus genomes came from outer space. But it’s too early to be considered as a theory.

Virus is the perfect candidate for the ‘alien’ label. Not just its absence of cells as the fundamental units of life, it differs from any existing living form and gets simpler than Cyanobacteria. How could evolution bring the existence of an ‘alien’?

The Birth

Some biologists have proposed a certain theory of virus origins.

In this section, let’s break down each of the theories, its proof and approaches, basis, and weaknesses

Classical hypotheses.

Studies done by biologists at the molecular level revealed infection by viruses to three domains of life. This suggested a probability that virus emergence had pre-date the divergence of life. It’s possible that viruses also emerged multiple times throughout evolution, often through displacement of ancestral genomes.

There are three (3) classical hypotheses on virus origins:

• Virus-first hypothesis: Suggested that viruses evolved from complex protein and nucleic acid molecules formed before the first cellular organism and the first replicating entities. The viral antique units then evolved into more organized, complex entity resulted in the Virus we know today.

• Based on an argument from a source. Viruses have replaced the ancestral bacterial RNA/DNA polymerases and primase during mitochondrial evolution, and the replacement of cellular proteins in the early evolution of DNA replication. Furthermore, the theory suggested that DNA replication proteins originated directly from the virosphere and later transferred to cellular organisms.

• Basis & Proof: Virus absence of cellular homologs (genetically encoded chromosomes) proved the antiquity of viruses. Virus also able to “hack” our cell-specifically control and modify cell’s mitochondria.

• Point-out:

• Supports that the virus emerged before the first lifeform. Its similar properties to an organism and its earlier emergence able to be a consideration that virus contributed to the rise of cellular life.

• Weakness: This theory has been dismissed by the majority of scientists because it violates the characteristics of a virus; it needs a host cell to reproduce.

Progressive hypotheses: Viruses once were mere mobile genetic elements, capable of moving within a genome and gaining the ability to exit and enter cells. It emerged after the rise of cellular lifeforms.

• Basis & Proof:

• This theory is integrated from the remarkable similarities between retrotransposons (components of eukaryotic genomes) and virus methods of cell hacking and reproduction. When a single-stranded RNA virus (Retroviruses, such as HIV) enters a host cell, its enzyme and transcriptase convert the previous SSR to the double-stranded DNA. The DNA then migrates to the nucleus and inserts integrase enzyme into the host cell’s genome; encoding it to produce more of its kind.

• Meanwhile, viral-like retrotransposons can also do the same. Research by Lander et. al. in 2001 has discovered empirical proof of these mobile genetic elements; they made up around 42% of the human genome.

• Point-out:

• The virus originated from an ancient genetic element of eukaryotic genomes. It developed to be a parasitic and infectious genetic substance, more complex than similar retrotransposons.

• Weakness: The hypothesis doesn’t account the uniqueness of Virus and its variety.

Regressive hypotheses: In contrast to the previous one, this hypothesis stated that the virus originated via a reductive or regressive process from a more complex eukaryotic organism (once a cell’s organelle) and developed to be parasitic and unable to self-replicate.

Basis & Proof:
Microbiologists agreed that certain obligate intracellular parasite bacteria, like Chlamydia and Rickettsia species, evolved from free-living ancestors.Viruses of one particular group, the nucleocytoplasmic large DNA viruses (NCLDVs) including smallpox virus and Mimivirus are bigger than most viruses. They possess 8-15 more genetic information: size, quantity of genomes, and viral enzymes. Because of its complexity, this type of virus has less dependence on its host when it comes to the replication process, allowing it to produce functional mRNA within the host cell cytoplasm.

According to proponents of this hypothesis, precellular lifeforms containing autonomous organisms developed a symbiotic relationship, further bonding together to form cells. However, in some cases, the relationship turned parasitic as one organism became more dependent than the other. Unfortunately, the previous bond assimilated essential genes responsible for the reproduction ability of a once free-living organism, transforming it into a genetic property only able to reproduce by hacking host cells.
The newest discovery on Mimivirus showed that it contains a large repertoire of translation’s putative genes, possible remnants of a previously complete translation system.

Point-out: The similarity between Rickettsia and Mimivirus and its relevancy to the theory of cell organelles origin is the main postulate of this hypothesis.

Weakness: The situation of “evolving backward” and symbiotic relationship transition is ambiguate. How this process might have occurred lacks details and is still filled with a lot of mystery.

Modern hypotheses.

The newer version of virus origins hypothesis which are the results of reevaluation, reconsideration of the previous hypothesis and the newest discoveries.

• Coevolution hypothesis (Bubble theory): A probability derived from virus-first and progressive hypotheses main point-out. Both had its weaknesses, then this neutralized both.

• Basis & Proof: Presents a scenario before the emergence of lifeform. At the early age of Earth, pieces of genetic information capable of self-replication called replicons existed alongside an abundant source of essential minerals and chemicals like a hot spring or hydrothermal vents. The food source gave rise to lipid-like molecules that could self-assemble into vesicles that, in turn, could enclose or envelope replicons. Replicons close to the food source thrive, but those farther away, depend on resources inside the vesicles. Henceforth, there were two paths of development for replicons due to evolutionary pressure: merging with a vesicle, which eventually gave rise to cells, and entering the vesicle to use its resources until depletion, which gave rise to viruses. ‘Despite a lot of contrary characteristics, the theory able to provide an approach that both virus and cellular lifeforms reproduction capability is caused by their same ancestors.

• Chimeric Origin Hypothesis: One of the newest hypotheses (proposed in 2019) by M. Krupovic, V. V. Dolja, and E.V Koonin. The hypothesis is based on the analysis of the evolution of replicative and structural model of viruses The hypothesis combines the regressive and virus-first hypothesis with a few modifications.

• Basis & Proof: Proposed that replicons of viruses originated from the primordial genetic pool. Different types of primordial replicons formed resulted in the emergence of viruses by recruiting the previous host proteins, responsible for the virosphere formation. The hypothesis implied viruses have repeatedly emerged throughout early life evolution stage, often through displacement of ancestral structural and genome replication genes

Conclusion
Today, viruses are something familiar to us

With every research development and discovery, we found what is responsible for pandemic disasters such as the black death (cause death for one-third of European population), influenza (the most devastating pandemic of all time, with total of 100+ millions of deaths), and many more. What was considered a “curse” or “god’s wrath” back then.

Viruses collapse our general understanding of what living things is and our civilizations a few times. Truth is, it’s something not more than a chain of genetic information with proteins

It’s magical and fascinating when we think deeply about it.