In the beginning…
Life on Earth is 3,500 million years old today… well, more or less. Living things have certainly been around on our planet for a very long time.
In case you hadn’t noticed, 3,500 million is a very long time indeed. (In fact, life may be as much as 4 billion years old!) Imagine that each of those years was one foot in length. How far would that line of feet run for?
Click the answer of your choice.
But now life is in trouble and I’m afraid the reason is you people. I’ll come to that in a moment but first,Professor Tiki prepares to speak
Early life on Earth was very simple — just tiny blobby things called bacteria.
After a while, slightly different green blobby things called algae began to appear.
These had ‘learned’ one very special thing: how to use the sun to make food. This was to be the most important development ever for future life on the planet. These tiny green blobs were the first simple plants. Algae eventually gave rise to plants with a stem and leaves like this one. And without plants, no animals could exist. If you were to hop into a time machine and go back 3,500 million years, you’d quickly die for two reasons: the air you breathed would be poisonous and there would be no food.
So why isn’t the air we breathe today poisonous?
This wonderful blue planet is home to all life. It’s the only home we have so it needs to be cared for.
In fact, most algae form strings rather than blobs.
Part of the ‘food’ of all plants and cyanobacteria
is a gas that is poisonous to us animals called carbon dioxide. They slurp this up, along with water and sunlight, to make sugars by a very clever process called photosynthesis
. And in doing this, they make what to them is a waste gas called oxygen. I’ll bet you know that no animal can live without it. So you see how important these little plants were then and still are today.
Try my Life on Earth Quiz
to see how you’re doing.
This photo shows strings of cyanobacteria. They are very tiny and used to be called blue-green algae when scientists thought they were just another type of plant.
Green leaves using the sun to make sugars to give the plant energy.
The wonderful web of life
Animals began to appear on the planet in a big way about 530 million years ago,
that lived in the sea. A little after this, plants began to grow on the land instead of just in the sea and were quickly
which wanted to
Then came the dinosaurs...
some dinosaurs were very big and some were very mean…and I’m sure
Later came penguins, polar bears,
at the very last minute
(just 200,000 years ago),
And right from the start, humans began damaging other life and the planet by
using fire carelessly.
Modern people are just beginning to understand a little about the web of life and the vital importance of biodiversity. They are beginning to realise that they have damaged it badly and, most importantly, that they depend upon it too. People are animals too, like penguins and porcupines.
OneZoom Tree of Life Explorer
lets you travel right into the Tree of Life. See if you can find humans! This is an incredible tool for finding out about every single mammal species on Earth, and it shows how each one is related to all the others. Go on, try it!
So now, why not try my Life on Web of Life Quiz to see how you’re doing.
Big Bangs and Mega Deaths
Have you heard about mass extinctions? Probably not… People are gobbling up more than their fair share – which means other creatures die.
…but because of people doing so much damage to the planet and to the web of life, lots of animals and plants are dying out completely. That’s what extinction is. And once a creature is extinct, that’s it. There are no second chances. It’s gone for ever.
But there’s nothing new about mass extinctions. Ninety nine percent of all the different types of life — called species — which have ever lived are now extinct. What is completely new is that this is the first extinction caused by people and their wasteful and polluting ways. All the other extinctions in Earth’s long history seem to have been caused by violent natural events. A fireball from space was likely to have been the main reason for extinction of the dinosaurs
The best known of these was the final extinction of the dinosaurs 66 million years ago.
Less well-known but much worse was a mysterious mega-extinction that happened about 252 million years ago. This was so bad that it destroyed around 96 percent (96 out of every hundred) of all lifeforms on the planet.
Understanding mass extinction shows that the global life system is delicate. If it’s messed up, it could mean the complete collapse of the life-support systems we all depend upon.
Humans could easily go extinct. The important lesson to learn from mass extinctions is that they hit complex life hardest. It’s things like bacteria and rats and cockroaches that survive — not people or (sob!) penguins. You have been warned!
Try my Big Bangs and Mega Deaths Quiz
Apocalypse soon: the beginning of the end?
Are people really threatening life on the planet? What’s the evidence?
One good way to find out what’s going on is to look at ‘indicators’ — you know, rather like traffic lights.
Traffic signals are indicators where red means danger – stop! Green means clear, go-ahead; amber means caution, watch out; and red means stop! I’d say these traffic light indicators are on red.
Let’s look at some examples of indicators.
The most famous forests in the world are those of the Amazon in South America, but there many others. Some are in the tropics (tropical rainforest) but most are in Russia and Canada (Boreal forest
). It is the tropical rainforests
which are particularly rich in different types of plants and creatures.
Peole using chain saws kill millions of trees every year
these forests more and more both for their timber and to make new ranch land for raising yet more animals for rich people to eat (poor people can’t afford meat), palm oil plantations and crops like soybeans . The boreal forests are going fast too, mostly for making paper for newspapers, magazines and offices.
“… most experts agree that we are losing upwards of 80,000 acres of tropical rainforest daily, and significantly degrading another 80,000 acres every day on top of that. Along with this loss and degradation, we are losing some 135 plant, animal and insect species every day — or some 50,000 species a year — as the forests fall.” Source: Scientific American
Remember, it’s not just the trees that are lost but all the animals whose home the forest was like monkeys, tigers or parrots.
According to the World Resources Institute, more than 80 percent of the Earth’s natural forests already have been destroyed
– Source: National Geographic
The World Wildlife Fund says an area the equivalent size of 300 football fields of rainforest is cleared each hour to make way for palm oil production. Say no to palm oil.
What are soybeans used for?
Most (about 75 percent) are used as animal feed to increase meat production. You could say the ever increasing demand by humans for meat is costing the Earth when you think about it. Not only rainforests are destroyed but the millions of farm animals also produce massive amounts of greenhouse gases and create serious water pollution affecting both rivers and the sea.
Drying up? Lakes, rivers and wetlands
These are home to many species like birds, amphibians (such as frogs , toads, and newts) and fish. Yet in the last few decades, these creatures have declined greatly in numbers and in health.
Particularly worrying are frogs and other amphibians. Nobody knows for sure why these little animals are dying so fast but it seems likely that chemical pollution (particularly certain types of pesticides) and global warming are at least partly responsible.
The primary causes of amphibian extinctions are pollution, loss of habitat, climate change, invasive species, road mortality, over-harvesting for the pet and food trades, and the infectious disease chytridiomycosis, which is spread by human activity.
– Source: Save The Frogs
And there’s the usual problem with humans wanting more land for farming and cities, so wetlands get drained and rivers get ‘tamed’ to try and stop them flooding. Then some people have powerboats and go fishing for fun and others like shooting wetland birds for fun.
Sad case of river dolphin
This dolphin, the ‘baiji’, used to be found only in China’s longest river, the Yangtze. There were about 400 in the late 1980s but by 2006, it had become extinct.
Source: National Geographic
The very existence of frogs worldwide is being threatened by a killer fungus.
A toad; very useful in the garden. Photo: Kristie
The fiery Luristan Newt.
The seas and oceans
As you know, the sea is home to many animals including fish (yum! Sorry but I have a thing about fish) and mammals like seals and whales and dolphins. And, most importantly so far as I’m concerned, it’s home to many types of seabirds including penguins like me! And — you guessed it! — many of my seabird friends are in trouble. Our numbers have dwindled by over a third in under 30 years. Every single one of the albatrosses, those huge majestic birds of the wild stormy oceans, is in some kind of trouble and three species are critically endangered. And yes, several types of penguin are threatened and three are including the little Galapagos penguin.
Part of the reason wildlife in the seas is having problems is that people are taking much more than their fair share. And it’s not as though people even eat all the fish they catch. Lots of the fish are just ground up to make fertilisers or food (fish meal) for other animals (like fish-farmed salmon) which people then eat.
Fish are in trouble too. The world’s fishing grounds, once home to a wonderful mix of different creatures, are dying as powerful ships with big trawling nets and sonar systems to spot fish shoals suck up millions of tons of fish, including young ones which aren’t even old enough to breed and make more fish. Perú once had the world’s biggest fishing industry. That collapsed because of over-fishing. Likewise, the Grand Banks — a vast area of shallow water east of Newfoundland in Canada — used to be bursting with fish like cod. That fishery collapsed in the early 1990s, destroyed by people’s greed.
Now another sea is almost fished to extinction: the North Sea (north west Europe). Here, big cuts in the number of fish people can catch have been ordered by governments to try and stop the collapse.
One of my relations in South Georgia, coming back from fishing. Thanks to Peter Barham for this picture.
Now, people — never learning lessons and always wanting to make more money — have started fishing in the Antarctic Ocean and are even sweeping up the krill which all seabirds like me, whales and seals depend on as well as the fish themselves. And some countries are still killing whales.
Coral reefs – Have you ever seen a coral reef? These are home to an awesome variety of plants and animals rather like the tropical rainforests on land. They are very beautiful too. But they too are in big trouble and many are dying because of what is called bleaching.
World’s biggest reef badly damaged
Australia’s Great Barrier Reef (and many others around the world) was seriously damaged in 2015-16 by the worst bleaching event ever recorded. This was because of a serious El Niño event caused, almost certainly, by global warming
Now: how about having a go at my Indicators Quiz to check out how you made it through that scary part of my guide.
You can check out whether an animal is in danger in the IUCN Red List.
Antarctic Ocean with huge iceberg.
Krill (Euphausia superba) are little shrimpy things. They, along with other crustaceans such as copepods, are at the bottom of the food chain in the Antarctic Ocean. Without them, there would be no fish, seals, whales or seabirds. Humans are now beginning to disrupt this food chain by catching millions of these tiny creatures.
Shame on them!
Japan, Iceland and Norway between them kill hundreds of whales every year.
Now do you see what I mean when I say life is in trouble? Stop!
All the indicators are on red; stop! Help! And the trouble (sorry! I always seem to be having to say this) is you people. You’re
- cutting down forests
- covering good land in concrete, buildings and new roads
- polluting the land, air and water (seas, rivers and lakes) because of cars, airplanes, ships, farming chemicals and fertilisers, garbage (especially plastic), sewerage, fish farming
- vacuuming the oceans of fish so that in many parts there are hardly any left
- trying to kid yourselves that there’s no problem
People are even covering the seas in garbage and other pollution like oil spills
All these things cause other animals and plants to die off and become extinct… and they are doing in a big way. They either starve to death or are poisoned. But the biggest cause of this man-made extinction is loss of habitat — the destruction of places in which creatures used to live.
RARE: A celebration of wonderful life from Joel Sartore on Vimeo.
Five ways people are wrecking the planet
- Climate Change and ozone-destruction caused by pollution from humans’ machines could completely upset global weather patterns and cause catastrophe. No-one yet knows what will happen but we do know it is already starting
- Over-hunting for food, for fur or, nowadays, fun. Thousands of creatures have been wiped out by people. Some of the most famous are the dodo, the passenger pigeon and the great auk.
- Introducing alien species. Sometimes people do this by accident but often it’s deliberate. Australia is one of the most notorious examples of the damage done by alien species. European migrants brought with them many animals and plants and some of these have become serious problems. Cats, foxes and rats have driven many once common creatures almost to extinction by hunting them. Rabbits are a serious pest too because they breed so fast, eat almost anything green and are almost impossible to control. And then there’s the great cane toad disaster…
- Destroying the natural world by cutting and burning rainforests, covering the ground with more houses, office blocks, factories and roads or using life-destroying farming methods
spraying poisons on crops
- Genes could be in trouble too. If you’ve read my guide about genetic engineering, you’ll know that they are the building blocks of life. And yes, they’re in trouble because of what people are doing to them. This is partly because of genetic engineering and partly because the gene pool is getting smaller.
Genetic engineering could make matters even worse because the world could come to depend on even fewer varieties of food crops. And many of these could be controlled by the big corporations who will own the seeds…
Or genetic engineering could make matters much better because fortunately, a great deal of research into improving food crops using genetic engineering is open-source.
The common sense solution is to learn from nature and be sure to preserve that wonderful mix of genes which gives us all that even more wonderful variety of life.
Try my Wrecking the Planet Quiz to see how you’re doing.
By “wrecking the planet”, I mean people are damaging that part of the planet in which all we living things exist: the biosphere
What is climate change?
I have made a guide about climate change — also called global warming. Click here to see it now.
What is pollution?
I have made a guide about pollution. Click here to see it now.
Dodo, a flightless pigeon. It was discovered by humans in 1598 on the island of Mauritius in the Indian Ocean. 60 years later it was extinct, killed and eaten by humans and its habitat destroyed. Image: The British Library
Passenger pigeon, These beautiful birds once existed in vast flocks North America but these. Were rapidly hunted to extinction by humans and the last one was shot in 1900. Image: “Birds of eastern Canada” (1919)
Great auk. Because it was flightless and easily caught, the great auk was hunted to extinction by humans, the last recorded pair being killed in Iceland in 1844. Image: The British Library
What is the gene pool?
Everything that is alive contains thousands of genes. The gene pool is a sort of imaginary pool in which every single gene from every single living thing can be found. If some living thing becomes extinct, then some of the genes which were only found in that formerly living thing are lost forever. So the gene pool becomes a little smaller. Humans are causing many extinctions and so there are many potentially useful genes being lost all the time from the gene pool.
What does it matter to humans? Does anybody care? Answer
If an asteroid hits the planet and causes big trouble for life, nobody is to blame. Asteroids aren’t alive and they don’t think. But people do think and that looks like turning out to be more dangerous for other life than any asteroid. It is ‘thinking people‘ — supposedly intelligent and wise — that are bringing about this latest mass extinction.
Everyone knows about the famous mass extinction event 66 million years ago which killed off the dinosaurs. A large asteroid hit the Earth destroying about three quarters of all life. This was the fifth mass extinction event in the history of life on Earth. But now that humans are doing so much damage, we seem to be entering a sixth mass extinction
Anyone with a little vision can see the indicator traffic lights are on red. But hardly anybody seems to be looking.
There are none so blind as to those who will not see
– Proverb traced back to John Heywood, 1546
If lots of people drive cars and don’t stop at the traffic lights, you know what happens: there’s a huge crash and people get hurt or killed. Well that’s what is starting to happen to much of life on our planet. So why don’t people care? Why are they trashing the planet with their big feet?
Try my Big Feet Quiz
and see how well you score!
Now I have a special question for you: what is the most dangerous animal that has EVER existed? Can you guess? (Hint: no, it’s not T. rex or the great white shark!)
See my answer here
Why bother? Why is biodiversity vital for humans?
Perhaps you think it doesn’t matter if humans are causing a lot of living things to go extinct. Well, I bet you didn’t know about something called ecosystem services. These vital services — which people use for free without even thinking about them — depend on a healthy biodiversity.
What are people doing about it?
The Convention on Biological Diversity (CBD) came into being at the 1992 Earth Summit in Rio de Janeiro, Brazil. This was an attempt by most of the world’s nations to protect biodiversity. It has not been very successful so far because destruction of habitats and species extinctions continue faster than ever.
So it’s up to you young people to get moving and DO SOMETHING to help!!!
But what can I do, you ask?
Go to the next section to find out
For a start YOU care or you wouldn’t be reading this. And if people didn’t care, there wouldn’t be any organisations like WWF, RAN, Greenpeace, the Sierra Club and many others. Nor would there be national parks and other protected areas.
is the name for human beings given by scientists. It means “wise man “. Huh! Hubris or what?
But you are… which is really great because now you understand the problems better than most adults. And soon you will be an adult and then you can really do something to help life in danger!
What you kids can do to help!
Young humans like you will, as you grow up, increasingly hold the future of life on our planet in your hands. It is you who inherit the Earth. Adults — including your parents and family — are doing the damage today because many of them simply don’t realise what they are doing to the planet. But you do! So what you choose to do as you get older can make a big difference.
Here’s what you can do to start the ball rolling:
At home and at school
Tip 1 — The four Rs
Recycle everything you can
Reduce what you buy
Reuse what you can
If something is broken, see if you can repair it
Tip 2 — Start an eco-club
Grab the interest of your friends, parents and school teachers. How? Maybe you could make a presentation on your computer? Or a slide show? Or a poster? Or leaflets to give out? Get people who know about ecosytems, ecology and biodiversity to come and talk to your club and inspire you all! How do you do that? How about contacting your local university biology department?
Tip 3 — Set an example
Reduce your demands for energy and water in your home
- wear your clothes more than once before you wash them
- take showerstake short showers. Try to avoid baths: They waste water and energy
- turn electrical things off when you’re not using them
- use low energy lights like LEDs
- Get insulated! If you live in a cold region and your house isn’t insulated, the chances are your families’ energy bills will be high. Insulation is the way to go
Tip 4 — Vacations
Try to take your holidays nearer near home so you don’t have to do loads of travelling — particularly on airplanes. They are mega-polluters!
Tip 5 — Buy local
Buy items made or grown locally rather than from far away. This cuts out ‘food miles’.
Tip 6 — Grow some of your own food
If you have a little patch of ground or a garden, why not give it a try? You might be surprised at how easy it can be. And you can’t get more local than your own back yard!
If you have space, try composting waste food, vegetable peelings and stuff. You can even make compost in a small bin which contains special earthworms
Tip 7 — Cut the commute
Could your parents live closer to where they work (or the other way around) and near your school? You could discuss this with them at a family meeting! Then none of you has to travel so much
Tip 8 — Try not to use the car!
Cars = traffic jams + pollution, so use bicycles and buses whenever you can rather than cars. Better still, walk.
Tip 9 — Give wildlife a home
if you have a back yard or garden at home, see if you can make a pond. Bluetit (chickadee) at nesting box. Image: Hans OlofssonAnd how about making a wildlife refuge too? You know, somewhere for birds to nest (make bird boxes) with bushes and small trees — even heaps of sticks and leaves where small animals can hibernate in the winter. A tidy neat garden is not a good place for wildlife — especially if you spray pesticides and use artificial fertilisers.
Tip 10 — know your planet
find out more about our beautiful planet and remember that you have to share it with millions of other life forms (species), all of which have a right to be here
Good luck! The future of all of us depends on what you kids of today do to make sure tomorrow comes for people, penguins and polar bears…
What do you think about life in danger? Have you any good ideas about what we can do to make things better? If you do, please write to me. As long as your message is sensible and friendly, I promise to reply. Use the toolbar at the bottom of the page to contact me.
If you’ve found my Life in Danger guide useful, please would you be kind enough to make a donation to help run my website. I know you kids don’t have credit cards or anything but perhaps you could persuade either your parents or your school to make a donation. It’s so easy and you can do it here.
Click here to go to my Life in Danger links page to find out about groups concerned at what people are doing to all other Life on Earth.
In 2015, about 40 per cent of total U.S. (for example) energy consumption was used for heating buildings. And energy usually means pollution (unless your household only uses renewable energy – probably unlikely if you have no insulation). Pollution matters for all kinds of reasons; in particular, climate change. If you want to know more about pollution, energy and climate change, I have guides. Just click “Tiki’s menu”
Polluting aircraft Image: dsleeter_2000
Commuting is polluting
Millions of people spend hours every day, five days a week, driving to work and back. This is called commuting and it is immensely wasteful of energy and causes terrible pollution and, of course, traffic jams. There has to be a better way…
This is called biodiversity and is the whole purpose of this guide. All living things are part of different ecosystems and biomes – including humans who haven’t yet understood how ecosystems provide vital services upon which they depend. By the way, there are eight major biomes on our planet: tundra, taiga, four types of forest (temperate deciduous, temperate evergreen, tropical deciduous and — best known of all — tropical rainforest), grassland and desert.
My links to other sites
Roots and Shoots Join the wonderful Jane Goodall and becme the change
Global Footprint Network: Find out about Earth Overshoot Day and calculate your own ecological footprint.
Kiwi Conservation Club: New Zealand-based forest and bird conservation project for kids. Did you know kiwis could kick, have their noses at the end of their beaks and can live for 40 years? No? Neither did I. Great site for kids.
National Geographic – for kids
the Rainforest Foundation: Supports traditional peoples of the world’s rainforests in their efforts to protect their environment.
Survival International: Supports tribal people by helping to protect their lands and rights to it.
There are loads of places to visit so I’ve just selected a few which I like the best. And please avoid disappointment and don’t send me more links, no matter how useful you think they are. Lots of people do but I simply don’t have time to deal with them. Sorry!