Animals Found to Digest Nature’s Original Bioplastic

Scientist pipetting blue liquid into test tubes — Photo: YanLev Alexey Sizov / Shutterstock

Scientists report that dozens of animals carry enzymes that break down nature’s “original bioplastic,” reshaping how we think about plastics and food webs.

Story Snapshot

Peer-reviewed research finds animals across nine phyla encode enzymes that degrade microbial polyhydroxyalkanoates (PHAs).
Lab tests show enzymes from a sponge, an earthworm, and a springtail break down PHA, confirming activity across distant groups.
Evidence spans more than 66 species, from marine worms and starfish to land dwellers like earthworms.
Older work found lipase-like activity in mouse and chicken pancreatic extracts on a PHA film, supporting biochemical plausibility.

What The New Study Found About Animal Enzymes

Researchers reported that animals across nine major groups have genes that can make enzymes which degrade microbial polyhydroxyalkanoates, a natural storage plastic made by bacteria. The team identified related enzymes in more than 66 animal species, including marine worms, starfish, sponges, and land animals like earthworms. The paper frames these enzymes as part of a wider, cross-kingdom system that recycles carbon stored in microbial PHA. This connects animal digestion to long-standing microbial chemistry in soils and seas.

Scientists then tested whether these animal enzymes actually work. Lab assays using enzymes from a sponge, an earthworm, and a springtail showed real breakdown of PHA. These tests confirm function across very distant branches of the animal tree, not just in one niche lineage. The activity supports the idea that animals can tap into microbial PHA as a resource. The exact share of animal diets from PHA in the wild was not measured in these reports.

Key Species And A Closer Look At A Notable Worm

The gutless worm Olavius algarvensis appears as an early animal host with a PHA-degrading enzyme that helps it use extracellular PHA. A University of Bremen dissertation identifies this worm’s enzyme as the first of its kind in an animal and suggests the host benefits from the degradation. The same dissertation reports 67 additional animal species with at least one such enzyme, matching the large spread noted by the institutional summary and extending the genetic map of this trait.

Prior biochemistry offers helpful support. A 2016 study showed pancreatic extracts from mouse and chicken could depolymerize a copolymer PHA film, tying the action to lipase-like enzymes from animals. Those tests used organ extracts, not whole animals in nature. Still, they back the new genetic and functional data by showing animal proteins can attack PHA bonds. Together, the lines of evidence point to a broad and plausible animal role in PHA turnover.

Why This Matters For Plastics, Policy, And Public Terminology

Public debate often mixes up “bio-based,” “biodegradable,” and “compostable.” Microbial PHA is a natural polyester that microbes break down. Many commercial PHAs are biodegradable under defined conditions, but that does not make all plastics safe or quick to vanish everywhere. Studies warn that mixed terms fuel confusion and greenwashing in packaging claims. Clear language helps voters and buyers judge real environmental impact, which many feel elites and agencies have muddled.

This research does not say animals can digest modern fossil plastics. It shows that animals have tools to break down a specific, natural biopolymer that bacteria make. That is a big biology story first, with policy echoes second. If companies or agencies cite it, they should be precise. People across the political spectrum want straight answers, not slogans. Good science can guide better rules and spending when leaders focus on facts over talking points.