The snail shell is long

Shells of some Atlantic snail species - an important link in the food chain - have grown considerably over the last century, a new study finds.

Using a collection from the Philadelphia Academy of Natural Sciences, a group of researchers measured the size of 19 pods collected from 1915 to 1922, then compared them to samples from the same 19 locations today. .

They found that the length of the shell has increased by 22.6% since the beginning of the 20th century so far.

The research leader, Jonathan Fisher of Queen's University, Canada, said: 'We found that the shell size increased significantly, which could affect the entire food chain of the coast.'

Snails are eating oysters on the coast of Maine. (Photo: Jonathan AD Fisher)

Previous studies have found that larger snails often eat oysters and oysters, while at the same time resting between shorter meals than smaller sized snails.

Researchers are also not sure why snails grow so big and so fast.

Fisher said: 'Many environmental changes recorded between stages can affect the rate of growth or survival of snails. The predatory fish are getting less and less, which can facilitate the development of snails. '

Today's water temperature is warmer than 100 years ago, which could also be the factor that makes snails grow faster.

Fisher concludes: 'However, whatever factors contribute to the increase in the size of snails, the marine environment is changing rapidly. That's the important thing'.

The study is published in the journal Proceedings of the National Academy of Sciences number March 23