![Narwhal tusks reveal mercury exposure related to climate change](https://www.naturalpress.ca/wp-content/uploads/2021/04/narval.jpg)
Narwhal tusks reveal mercury exposure related to climate change
Like rings in a tree trunk, a narwhal’s tusk provides a window into changing conditions in the Arctic
Like rings in a tree trunk, a narwhal’s tusk provides a window into changing conditions in the Arctic