The Earth’s core is cooling down very slowly over time. One day, when the core has completely cooled and become solid, it will have a huge impact on the whole planet. Scientists think that when that happens, Earth might be a bit like Mars, with a very thin atmosphere and no more volcanoes or earthquakes. Then it would be very difficult for life to survive – but that won’t be a problem for several billions of years.
A lake community with four trophic levels suddenly suffers from algal blooms. Using the strategy of biomanipulation, an ecologist may propose removing zoonplankton.
