Viruses

What are viruses?

It is hard to call them living organisms, but we may consider them as an alternative definition of life!

For a long time, scientists said no because viruses don’t have cells, can’t make their own energy, and must use a host cell to reproduce.

But new discoveries show viruses are much more active and complex than once thought. They don’t just “hijack” cells—they reorganize cell parts, build viral factories, and control cell processes to make more viruses.

Giant viruses like Mimivirus have surprisingly large genomes, even with genes once thought unique to cells. Other strange viruses, like ones that grow tails outside of cells or the Sputnik virophage (a virus that infects another virus), challenge old definitions

Viruses are also everywhere in nature—especially in the oceans—where they affect ecosystems, nutrient cycles, and evolution. They are a major source of genetic innovation and may have shaped life on Earth.

Some scientists now suggest we should think of viruses as a special type of living organism, not separate from life but deeply connected to it.

Viruses are not just passive parasites. They are powerful, creative forces in biology, and our definition of “life” needs to change to include them.