Goodbye, for now

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.

  1. How does the use of pesticides across Europe and Africa affect the survival of house martins?
  2. How could we conserve our populations of house martin?

Fruits of the autumn

Time travellers to Nowhere (3)

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.

In Nowhere Wood, everything is connected together, in space and in time.

 

So many adventures in space and time, so much opportunity for the evolution of new forms. All of which depends on the formation of sandstone in Nowhere Wood.

  1. Imagine what it was like to live in Nowhere Wood 300 million years ago. What would be the same and what would be different.
  2. How do you think the world will change in the future?

Safety in numbers

Time travellers to Nowhere (2)

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.

Today, humans have found the coal and burned it, putting the hidden carbon dioxide back into the air, re-warming the planet. No we face a global warming, not a global cooling. Perhaps, one day, Nowhere Wood will be destroyed for a second time.

  1. Think about how interconnected the rocks, the trees, the atmosphere and the climate are. How does a change to one thing affect everything else?
  2. Ferns are the first group of plants to develop proper roots. Think about why it would be an advantage for the early tree ferns to grow into sandstone.

Back then, the tree ferns grew through sandstone much as the smaller ferns in Nowhere Wood do today. Read more about this in another story: Climbing the walls.

Time travellers to Nowhere (3)

Time travellers to Nowhere (1)

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 weathered by the stormy wind and rain. Cascades of small, eroded particles surge down the mountain slopes, transported in the muddy river waters.

Mountains become tiny grains of sand settling at the bottom of the smaller streams running through Nowhere Wood. Layers upon layers of sediment are depositing in the streams, blocking the channels. Over time, the increasing weight of sand squeezes the water out, cementing the grains together to form sandstone. These are the cliffs we can see today at the far end of Nowhere Wood. It is called Pennant sandstone and was quarried to make roof tiles for the people of the town.

 

  1. It is easy to think of living organisms having uncertain adventures through time and space. But the same is true of rocks, although on a much larger time scale. Find out where the matter that makes up planet Earth originally came from.
  2. Think about what has happened to the sandstone in Nowhere Wood since it was formed.

Time travellers to Nowhere (2)

Early risers!

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.

1. How have people helped the snowdrop to survive for so many years?

2. What advantages do snowdrops have by storing their food in underground bulbs. Can you think of any possible disadvantages?

Snowdrops have many more secrets that help them in their adventures in time and in space. We may tell more stories about snowdrops in the coming days! Come back to read them.

Time travellers to Nowhere (1)

Moving things on

The weather is warm and wet in Nowhere Wood.

These are perfect conditions for growing the fungi that spread  everywhere throughout the soil of Nowhere Wood. Fungi are Nature’s recyclers, feeding on the fallen leaves, fruits and wood.

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 hyphae). Some fungi can spread out over really large areas, several kilometres wide.

At this time of the year, the fungi are busy ‘ being’.

Then one night, silently and without warning, the fungi do something else.

They produce structures that we call “mushrooms” **.

Mushrooms are  fruiting bodies. They produce thousands of tiny spores.

Spores are small and light. They are carried on air currents to new places in Nowhere Wood, where they will germinate and grow into new hyphae.

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.

Then, almost as soon as they arrive, it is all over. The fruiting bodies die and become food for other fungi and bacteria in Nowhere Wood.

This is how it is. The precious molecules are used, recycled and become part of the growth of new organisms. Nothing is ever wasted.



 

  1. All of the atoms in the world were made when the universe began. No atoms have been made or destroyed since then. Imagine what life would be like without Nature’s recyclers.
  2. You are a collection of recycled atoms. Think about how carbon atoms enter and leave your body. [Hint, carbon atoms are found in carbohydrates and in carbon dioxide.]

You can read more about ‘being and becoming’ here.

 

**Some mushrooms are good to eat, others are really poisonous and can kill us. It is hard to tell them apart unless you are an expert, so it is sensible not to touch or eat any mushrooms you find in a wood.

Climbing the walls

Counting the ways to stay alive

No one knows how many different kinds of animals and plants are alive today, and, sadly, we never will.

A survey in 2011 suggested that there are nearly 8 million species of animals and nearly 300, 000 species of plants.  Astonishingly, nearly 90% of these species have yet to be discovered, described or named. Many are found in hard-to-reach places, such as tropical rain forests or the deep oceans. Given the rate of man-made habitat destruction, it is possible that many of these species will become extinct before they can be named by scientists.  

These 8.1 million species are, for now, the success stories of evolution. Each is a unique way of solving the problems of surviving and reproducing in an unforgiving and changing environment.

All species, like this humpback whale, have special characteristics that allow them to survive in their chosen habitats.

But if the habitats change too much, such as when when the oceans become acidified, rainforests are cut down or burned, then species may no longer be able to survive and they become extinct. Forever. 

  1. Why does it matter that species of organisms become extinct before scientists can discover them?

Organise and stay alive

Trampling acorns underfoot


I have never seen so many acorns in Nowhere Wood. Everywhere I step, I am treading on acorns. Acorns are the fruits of oak trees and this year it certainly has been a bumper harvest.  Biologists call this a “mast year”.

The air in Nowhere Wood in April and May was very hot and still. This allowed the oak pollen to hang in the air near the feathery stigmas of the oak flowers. Perfect conditions for pollination and making acorns.




July and August were warm and wet, ideal conditions for growing a record crop of acorns.

This is good news for the birds of the wood, like pigeons, jays and woodpeckers, which eat acorns. And for the squirrels and mice, too. Deer eat acorns, and I did once see one near the woods very early in the morning. The oak trees are producers and this is one way that they make food for the woodland herbivores.

The oak trees in the wood are perhaps seventy or eighty years old now and tower above the other trees. They are successful, but for how much longer? The oldest trees are falling down, some by lightning strikes during thunderstorms.

It is difficult for young acorns to grow into oak trees, because the floor of the wood is covered by thick ivy and brambles. There is a battle going on here for light, space and water that makes an episode of Eastenders look tame!

Some young shoots make it through to the light, but they are few and far between. The future of acorns in Nowhere Wood will depend on them.

Everything is connected together, and a change to one organism affects everything else. The squirrels and the jays will be needing the oaks to remain successful. This is the way of life in Nowhere.



 

  1. Walk round an open space or a park near where you live. How are the living organisms depending on each other to survive?



Squirrel wars