🪱 Animals Have Been Eating Nature’s “Bioplastic” for Millions of Years

Long before humans invented biodegradable plastics, bacteria were already making their own.

Many microorganisms produce compounds called polyhydroxyalkanoates, or PHAs — natural polyester-like materials that they store inside their cells as reserves of carbon and energy. Scientists had long assumed that breaking down these microbial plastics was essentially a job for microorganisms themselves.

Then researchers studied a very strange animal: Olavius algarvensis, a tiny marine worm with no mouth and no gut. It survives by hosting bacteria beneath its skin and digesting them for nutrition. Some of those bacteria store as much as 42% of their cellular carbon in PHA.

The researchers discovered that the worm produces its own enzyme capable of breaking PHA into smaller molecules it can use. And it is not alone. Related enzymes turned up in more than 66 animal species across nine major animal groups, including sponges, starfish, earthworms and springtails. Laboratory experiments confirmed that enzymes from several distantly related animals really can degrade PHA.

The finding reveals a previously overlooked route through which carbon stored by microbes enters animal food webs — and suggests animals may have been consuming nature’s original bioplastics for hundreds of millions of years.

Humans invented biodegradable plastic.

Evolution apparently invented both the plastic and something to eat it.

#Biology #Evolution #Bioplastic #Ecology #Microbiology #Science

https://www.nature.com/articles/s41559-026-03153-8