Our Journey as Life on Earth
'We belong to a planet four and a half billion years old. To make relative time periods easier to grasp, let us look at the entire history of our Earth as a single twenty-four-hour day starting at midnight. In this day of planet-time, each minute would mark the passing of more than three million years.
'At first, the planet was as hot as an erupting volcano. Being formed by the gravitational pulling together of materials orbiting the sun, it was continually showered by meteorites. Shortly after midnight, a chunk of matter the size of a small planet had collided with Earth, the impact causing materials to be thrown outward into space to form the moon. It took till nearly two in the morning for the planet surface to cool down enough for steam in the atmosphere to condense into rainfall. As rain fell and kept falling, the oceans were born.
'Between three and four in the morning, the first forms of life appeared in warm, shallow water. There were only traces of oxygen in the atmosphere and no ozone layer to provide protection from incoming ultraviolet radiation, which was too strong to allow life to develop on land. It took till ten-thirty in the morning for photosynthesis to evolve, and from then on, those early green life-forms started producing oxygen as a waste product.
'All life-forms were single celled and remained so for the rest of the day, the first more complex multi celled organisms not evolving till half past six in the evening. By eight, worms had appeared at the bottom of shallow seas, followed an hour and twenty minutes later by the first fish. By a quarter to ten, plant life had become established on land; soon after ten, amphibians and then insects appeared.
'At twenty to eleven, disaster struck in what has been described as the mother of all extinction events. A combination of volcanic activity, asteroid impacts, and other disasters wiped out 95 percent of life, though that left plenty of room for the dinosaurs to emerge afterward as the dominant vertebrates on land. The age of the dinosaurs lasted till twenty to midnight, when a six-mile-wide meteorite struck earth and caused a dust cloud to block out so much sunlight that the decline in plant life killed off many large animals. Mammals, who had been quietly in the background for the last hour, emerged to fill the niche of dominant vertebrates on land. The minutes later, some mammals returned to the sea and slowly evolved into whales and dolphins.
'At two minutes to midnight, a small ape in Africa became the last common ancestor of both humans and chimpanzees. At just twenty seconds to midnight, apelike hominids discovered the use of fire. The entire history of our species, from its early origins in Africa, is contained in the last five seconds before midnight.
'Within the story of Business as Usual, a commonplace saying is ‘you can’t change human nature.’ But when we look at the breathtaking span of our planetary history, the idea that ‘we’ll never change’ seems absurd. We are part of the most extraordinary unfolding. Where will it go next?'
- Joanna Macy and Chris Johnstone, ‘Active Hope.’
'At first, the planet was as hot as an erupting volcano. Being formed by the gravitational pulling together of materials orbiting the sun, it was continually showered by meteorites. Shortly after midnight, a chunk of matter the size of a small planet had collided with Earth, the impact causing materials to be thrown outward into space to form the moon. It took till nearly two in the morning for the planet surface to cool down enough for steam in the atmosphere to condense into rainfall. As rain fell and kept falling, the oceans were born.
'Between three and four in the morning, the first forms of life appeared in warm, shallow water. There were only traces of oxygen in the atmosphere and no ozone layer to provide protection from incoming ultraviolet radiation, which was too strong to allow life to develop on land. It took till ten-thirty in the morning for photosynthesis to evolve, and from then on, those early green life-forms started producing oxygen as a waste product.
'All life-forms were single celled and remained so for the rest of the day, the first more complex multi celled organisms not evolving till half past six in the evening. By eight, worms had appeared at the bottom of shallow seas, followed an hour and twenty minutes later by the first fish. By a quarter to ten, plant life had become established on land; soon after ten, amphibians and then insects appeared.
'At twenty to eleven, disaster struck in what has been described as the mother of all extinction events. A combination of volcanic activity, asteroid impacts, and other disasters wiped out 95 percent of life, though that left plenty of room for the dinosaurs to emerge afterward as the dominant vertebrates on land. The age of the dinosaurs lasted till twenty to midnight, when a six-mile-wide meteorite struck earth and caused a dust cloud to block out so much sunlight that the decline in plant life killed off many large animals. Mammals, who had been quietly in the background for the last hour, emerged to fill the niche of dominant vertebrates on land. The minutes later, some mammals returned to the sea and slowly evolved into whales and dolphins.
'At two minutes to midnight, a small ape in Africa became the last common ancestor of both humans and chimpanzees. At just twenty seconds to midnight, apelike hominids discovered the use of fire. The entire history of our species, from its early origins in Africa, is contained in the last five seconds before midnight.
'Within the story of Business as Usual, a commonplace saying is ‘you can’t change human nature.’ But when we look at the breathtaking span of our planetary history, the idea that ‘we’ll never change’ seems absurd. We are part of the most extraordinary unfolding. Where will it go next?'
- Joanna Macy and Chris Johnstone, ‘Active Hope.’
