Barney and Gemma meet the sports stars of the sea - sprinters, jumpers and even gymnasts!
Barney and Gemma show that coral reefs are like our cities - and everyone has a job to do.
Monty Don travels to Japan in spring to trace the history of Japanese gardens from early boating gardens, through Buddhist temples and Zen gardens, right up to a modern tea house.
The UN predicts that the human population could reach 10 billion people by the year 2050. Broadcaster and naturalist Chris Packham investigates why our population is growing so rapidly, what impact it's having on the natural world, and whether there is anything that can be done.