Long before humans invented plastic, nature had already created a similar material.

Scientists have found that microorganisms have been producing natural plastic-like substances called polyhydroxyalkanoates (PHAs) for hundreds of millions of years. These substances are found in places such as soil, oceans and sediments. Unlike most modern plastics, PHAs can naturally break down.

A tiny marine worm gave scientists a clue

The discovery began with a small marine worm called Olavius algarvensis. The unusual worm does not have a mouth or digestive system. Instead, it lives with bacteria under its skin and gets nutrients from them.

Researchers found that some of these bacteria store carbon in the form of PHA. They also discovered an enzyme in the worm that can break down this natural plastic and release smaller molecules that the animal can use.

The ability may be common in animals

Scientists then looked at the genes of other animals and found similar enzymes in more than 66 species across nine animal groups.

Laboratory tests also showed that enzymes from animals such as earthworms, sponges and springtails could break down PHAs. This suggests that the ability to digest these natural plastic-like materials may be much more widespread than scientists previously thought.

Could nature help solve the plastic problem?

The discovery is especially interesting because scientists are already making PHA-based bioplastics as an alternative to traditional petroleum-based plastics. They are being explored for products such as food packaging, agricultural materials and some medical applications.

Researchers believe studying how animals naturally break down PHAs could help us better understand how biodegradable plastics behave in the environment.

However, scientists are still studying how important this process is in nature and whether it could play a meaningful role in tackling today’s plastic pollution problem.

The bigger lesson is simple: nature may have already developed a way to make and break down plastic-like materials. Scientists are now trying to understand that natural process – and see what humans can learn from it.