Katie has a PhD in maths, specializing in the intersection of dynamical systems and number theory. She reports on topics from maths and history to society and animals. Katie has a PhD in maths, ...

It is not pleasant to imagine that human activity is making the planet uninhabitable, but we typically think of this in terms of greenhouse gases, rising sea levels or acidifying the oceans. We aren't ...

The planet’s demand for salt comes at a cost to the environment and human health, according to a new scientific review led by University of Maryland Geology Professor Sujay Kaushal. Published in the ...

The vast majority—97 percent—of the earth’s water is salt water found in our oceans. Another two percent is stored in ice caps or glaciers. That leaves just one percent of all water on earth for ...