National security, unlocked. Each Thursday, host Mary Louise Kelly and a team of NPR correspondents discuss the biggest national security news of the week. With decades of reporting from battlefields ...

Computational models are mathematical models used to numerically study the behaviour of complex systems by means of a computer simulation. A computational model can be used to make predictions of the ...

Indicator species are living organisms that tell us that something has changed or is going to change in their environment. They can be easily observed, and studying them is considered a cost-effective ...