By late October, the last of the visitors are leaving Nowhere Wood. House martins are birds that build nests in the eaves of the surrounding houses. They fly by swooping up and down in the summer skies, feeding on flying insects.
Then, suddenly, as the season changes, they leave. But where do they go?
Amazingly, for such confident, visible, birds, they have been able to keep this a secret from us. And, even today, we really do not know for sure. We think they fly to Africa, over the Sahara Desert, to countries like Cameroon, Congo and the Ivory Coast. That’s a journey of over 5 000 km.
There they spend the winter, feeding and resting, before making the return journey in early Spring, arriving back to Nowhere Wood by April.
If all goes well, they return to the wood, and even to the same nests. It is a dangerous adventure and not all make it back. The birds can be eaten by birds of prey, or trapped by hunters.
Above all, the declining number of insects is killing the house martins. Loss of habitats, use of pesticides and climate change are all linked to human activity, so indirectly, we are to blame. So, perhaps, in the future, it will not be goodbye for now, but goodbye forever.
- How does the use of pesticides across Europe and Africa affect the survival of house martins?
- How could we conserve our populations of house martin?
We are in Nowhere Wood, about 300 million years ago, staring at a forest of tree ferns, watching them make oxygen. Over the years, these tree ferns have made so much oxygen that its concentration in the air has risen to about 35%, (compare that with the 21% found in the 21st century).
There is so much oxygen that the lightning strikes produce frequent explosions in the air, causing forest fires. Nowhere Wood is a dangerous place to be, sometimes.
The animals are using the oxygen to grown large: some millipedes are 1.5 metres in length and 0.5 metres wide. Some dragonflies have 70 cm wingspans.
With all of this food available, there are opportunities for new carnivorous lizards to appear, including Hylonomus. This is one of the first creatures to have a new eggs with membranes inside, a characteristic later shown by all birds.
Also the flesh-eating Anthracosaurs first appeared at this time. These are the direct ancestors of the dinosaurs, that appeared millions of years later.
We are not alone in Nowhere Wood, about 300 million years ago. We are deep in a forest of tree ferns, towering above us, fifteen metres high. The damp air has a sweet and woody fragrance, heavy with 
The plants are silently photosynthesising, growing ever taller and adding oxygen to the air. Year after year, generation after generation.
The wood in the tree stems is a new invention of evolution: no other plants have wood and fungi have yet to discover a way to eat it. This means that when the trees die and fall into the swampy wet soil, they do not decay, but stayed for thousands of years, gradually 
The tree ferns took carbon dioxide from the air and locked it away as wood and coal. They took so much and the amount of carbon dioxide in the air fell so much, that the climate cooled, lead to the destruction of the tropical forests.
Imagine you had a time machine, where and when would you go? Come with me back to Nowhere Wood, about 300 million years ago. That is long before humans, mammals or even dinosaurs existed, but frogs laid their eggs in pools, much as they do today. Today it is hot, humid and very quiet: with no birdsong or animal noise, apart from the distant croaking of frogs. Tomorrow, there will be a raging tropical storm and the mountain will be pounded by its violence.
Nowhere Wood is located just above the equator, and we are looking up at the aftermath of a series of global catastrophes, which has taken hundreds of million years to happen. Two continents collided and sent shockwaves through the land, pushing upwards to form the mountains that we can see ahead of us. We are in a valley, downstream from a range of tall mountain peaks.
The mountain rock is soft and is easily 
Mountains become tiny grains of sand settling at the bottom of the smaller streams running through Nowhere Wood. Layers upon layers of 
Every year, the snowdrop is the first plant to flower in Nowhere Wood. It is a symbol of the birth of Spring, bringing good cheer and hope at the end of a long winter. This is one reason why people plant snowdrops in their gardens.
Snowdrops are tougher than they look: they can grow through ice and snow. Their leaves have hardened edges that act as snowploughs and their cells contain a snowdrop antifreeze that stops ice crystals forming. The real secret of the snowdrop’s success is found below the ground, in the frozen soil. There, in the darkness, is a bulb, full of food made in last Spring’s photosynthesis. Like a battery, it is an energy store, so that the plant can start to grow in the weak winter sunshine.
This means that the plant can make leaves to grow in the warming Sun. The leaves make food to store in its bulbs ready for next year. Snowdrops do all of this before the leaves of the big trees open to steal the light, so that the floor of the wood becomes shaded. By then, the work of the snowdrop is over and it can wait for the next winter.
Fungi feed on the wood of the dead oak trees, turning it into nutrients that provide energy and chemicals needed to grow new fungal cells. (These cells form long threads called 
Then one night, silently and without warning, the fungi do something else.
Mushrooms are 
Spores have often been found in the filters of jet aircraft flying at the edge of the atmosphere, so some spores can travel right round the world. When fungi produce spores they are ‘becoming’ something new: small, light and mobile versions of themselves.
The air in Nowhere Wood in April and May was very hot and still. This allowed the oak 
