Reviewed by Ian Mowll
This series is on iplayer (in the UK)
This is a series of 5 programmes about the 4.5 billion year story of life on Earth, through its many upheavals and blossomings and how we humans came to be on our planet.
This series particularly focuses on extinction events and how life on Earth bounced back each time, often more complex and more diverse than before. And how so often, each cataclysmic event was needed to make way for further evolution of life on Earth. More than this, the extraordinary number of factors that needed to be in place for modern humans to appear brings home to me how incredibly fortunate we are to be alive on this planet and how very precious life is.
The series starts with the Permian extinction 250 million years ago where 90-95% of all life on the planet disappeared – it’s probable that volcanic activity started the process.
The second programme is about “Snowball Earth”, an event about 700 million years ago where magma from volcanic activity washed into the sea and subsequently absorbed carbon dioxide. This cooled the Earth and set off a runaway freezing event until the whole Earth was covered in ice. Life survived in little pools on top of the ice until further volcanic activity warmed the Earth and life blossomed again.
Next is the story of plants and the advent of photosynthesis. Complex life started in the sea but eventually lichen (a synthesis of algae and fungi) spread onto land and helped to produce soil which laid the way for plants and trees to grow on land. But these plants sucked carbon dioxide out of the atmosphere which produced another great freezing event.
Then there is the story of the atmosphere – how it was created and changed over time. Cyanobacteria was the first organism to photosynthesise and produce oxygen and this dramatically changed life on Earth. Now the atmosphere is made up of oxygen, nitrogen, carbon dioxide and water vapour and these are all vital for life.
Finally, it’s the human story. A comet hit the Earth about 66 million years ago in Mexico causing a mass extinction with most of the dinosaurs going extinct. But this made way for the proliferation and evolution of mammals and eventually modern humans.
The series ends with the observation that the population of modern humans has grown dramatically and now affects the ecosystems of the Earth. Chris Packham concludes that we humans now need to do the most amazing thing we have ever done – put the Earth first so that life can continue to evolve and life systems are not devastated. He says that we have the ingenuity and ability to do it – we just need to make it happen.
The whole series is amazing. The journey of life on our planet is awesome and it seems that the chances of our existence today is so incredibly small – there have been so many twists and turns to produce life as we now know it. If we as a species can truly grasp this amazing truth, it can inspire us to take care of the eco-systems and play our part in this incredible journey of life on our precious planet.
A summary of the series can be found here:
And the series can be viewed on iplayer – with the first programme here: