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?
These animals look like cars parked in the autumn sunshine. They look harmless enough, but they have some 
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 spores, heavy with promise.
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 becoming compressed together to form deposits of coal.
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.
It is late February, the cold weather has moved away and the frogs have moved back in. It’s been a couple of years since they were last here, but here are their newly-laid eggs and the female is hiding beneath the leaf in the top left corner of the photograph. What is a frog and how is it having adventures in Nowhere Wood?
Frogs are amphibians, animals with backbones that live for most of the year on land, but which have to return to water to breed. A female with eggs is popular with males, which 
There are dangers in the water: tadpoles become carnivores and will eat each other and there are other predators, too. There is also a real chance that the water in the pond will disappear if we have a prolonged dry spell.
One week on, and the spawn has floated to the edge of the pond and the adds are swollen because they have taken up water. They still look healthy. Fingers crossed for the next stage!
Winter has come to Nowhere Wood and ice has formed around the fallen trees in the pond. Everything shivers and wood is silent again. Squirrels search for food in the frozen mud, but everything else is waiting, biding its time.
Silent, except for an ancient overgrown hedge formed from a row of old trees, bound together into a thicket by generations of bramble stems. These trees are singing, for this is the home of the tree sparrows. The trees are just outside the wood, next to a path much used by dogs taking their owners for a daily walk.
The tree sparrows are warm, protected from the icy wind by the layers of dead branches that surround them. Impenetrable, they are hidden amongst the branches, out of harm’s way. In this forgotten place, they thrive and they sing.
Nowhere Wood on December 23rd was silent and still. The wood was in midwinter, at its furthest point from the Sun on its journey through the seasons. At only 7 hours and 49 minutes, this was the shortest day and darkness ruled the wood. From now onwards the days will get longer by about two minutes each day until midsummer’s day in July.
The air was was misty and damp. No birds sang. The only movements were from ten or more baby squirrels running up and down trees, looking for food. The plentiful acorns in the autumn gave their parents the nutrients the needed to produce a special autumn litter.
Even by January, the wood had moved onwards and the days were drawing out. Robins sang from high branches of trees, marking out the wood into their territories, preparing for the coming spring.
Jackdaws and magpies fought for the right to control the high airspaces and the food that the neighbouring houses throw away. The wood was bustling with movement and sound.
Today is February 1st, the day that the Celtic peoples call Imbolc, the first day of spring. The flowers are opening and the frogs will soon return to our ponds to breed. Look upwards to the sky.
The leaves covering the floor of Nowhere Wood are slowly disappearing in the mild December nights. Fog hangs in the air. The wood is preparing for winter and everywhere is quiet and still. Most of the real action is taking place below the ground, but what is making the leaves disappear?
The bacteria and fungi feed on the leaves, turning them into nutrients that they use as food. This is 
Plant roots need plenty water, air and nutrients, all of which are given to the soil by the fungi and earthworms. We can think of earthworms as the soil’s farmers, ploughing the soil for the plants. Without their work, no life could exist in Nowhere Wood.
The famous scientist Charles Darwin studied how plants, earthworms and fungi work together to keep woods alive, and he wrote a famous book about it in 1881. He wrote about earthworms: “It may be doubted whether there are many other animals which have played so important a part in the history of the world, as have these lowly organised creatures.”
In is late November and the cells that will divide to make the new leaf are protected safely inside the 
Soon, the cells take up water and get much larger. They escape the protection of the bud and the new leaf 
The leaf is a factory for making sugar. Like any factory, it has a source of energy and transport systems to get the raw materials into the factory. It also moves the manufactured sugar out to the places in the plant where it is needed. The heart of the factory is the production line where sugar is made. These are called 
Gradually, in the autumn, when the days get cooler and shorter, the sugar factories are shut down and abandoned. The chloroplasts lie in ruins as everything useful is recycled back into the branches of the tree. All that remain are the frameworks of cell walls, turning brown as they dry in the autumn air.
Finally, the oak tree makes a special layer of cells that separates the old leaf from the stem, and the leaf is ready to fall when the wind blows strongly. The fallen leaves are not wasted, becoming energy stores for the organisms that feed on them. Next year’s buds are forming and wait for spring and the production of new leaves.
When you next look into a mirror ask yourself if you are the same person as you were yesterday. Well, of course you are.
So, when your friend sees you after ten years and calls out your name, there is not a single part of your body that was the same as when you last met. You have been completely remade and 
The genome is divided between a number of 
How can this hart’s tongue fern grow on a vertical cliff face about two metres from the ground.
Like fungi, another ancient group, ferns produce spores. They are the brown dots on the underside of this fern leaf. Spores are light and float in the air like particles of dust.
This is a fern, but it is not the mature adult form. It has tiny roots that grow into the humus, drawing nutrients from it. 
The gametophyte makes many small sperm that swim in the water on the surface of the plant. They swim towards eggs, which are much larger. This photograph shows a fern sperm fertilising a fern egg.
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.