Are humans more important than plants?

​​​​​​Isn’t a human life worth more than a plant’s? Humans need plants to survive though. And we’re destroying the earth by not caring for plants. But isn’t climate change just a myth? Hmm… this isn’t so obvious after all...

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Humans or plants: who’s winning?

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Would you save a dying plant before a dying human?

Do people matter more than plants and trees? We can’t live without them so is it time to show them more respect?


Humans vs Trees

Paramedics attending the scene of a car that’s crashed into a tree will automatically focus their efforts on saving the people in the car. They won’t check the tree for signs of life and try to bring it back the way they will a human. We assume people matter more than trees. But maybe we need to think about why. For after all, we couldn’t survive without trees while they’d do just fine without us… they wouldn’t have cars crashing into them for a start!

Dr. Joshua Shepherd (Philosophy Department at the University of Oxford) points out that some rare plants have needed humans to cultivate (look after) them so they would not have existed without human intervention. “But generally speaking if we all died, plants would continue to live.” This maybe makes us think just a little differently about that tree destroyed by the human driving a car.
We don’t have to think too hard to try to imagine the Earth without humans.  The short animation below explores the possible short-term and long-term effects:

Plants and vegetation would grow back and after a while, without humans to prune them back, would entirely cover all those man-made city skylines that we have come to recognise.

So what makes us think we're more important than plants?

“In philosophy there’s the technical term ‘moral status’ which means you have a reason for treating something a certain way,” says Joshua. So if a living being can feel pain or joy it’s deemed to have value and should be treated with respect. 

Humans are thought to have the highest level of moral status but some environmental activists disagree. “Some plants have a high status, for example the rainforest or plants from which we get food. And many medicines come from plants. But do you keep plants alive just for human survival rather than in their own right? It depends on your value system,” says Joshua.
Trees are alive, an ecosystem in their own right and an important part of our environment. But, conflicts between trees and people often happen. This can be due to a tree’s natural growth endangering human life, such as an overgrown branch hanging over a pavement or playground. And conflict can result from human activities impacting on trees - such as that car crash we mentioned at the beginning.

But trees, like humans, also have medics to look after them. It’s a tree surgeon’s job to maintain the health and welfare of trees. So humans help trees - the development of tree surgery indicates some people care about them a great deal. Many keen gardeners will tell you talking to their plants helps them grow. And even if it doesn’t, people enjoy growing them and having them in their homes and gardens. We get enormous pleasure from plant life.

Do people in the developed world have the right to demand that people in the developing world don’t build over their natural environments?

People are thought to be a higher evolved form of life than plants because we can experience and give great joy. We’re presumed to have a high degree of intelligence and sophistication and to make rational choices. Yet, some argue that humans aren’t always rational and can cause great suffering as well as joy. Whereas plants never set out to deliberately harm us - except in sci-fi novels such as ‘The Day Of the Triffids’ (by John Wyndham) when plants take over and kill people! Maybe the reason that story is so popular is because it touches upon a deep fear that plants might one day fight back? 

“We assume humans are vastly more important than plants but when you start to think of why that is, you can get to some interesting places,” adds Joshua. “For some people, all life matters. That would be the argument from environmental philosophers. Some argue you shouldn’t mess with nature unless you have a very good reason, e.g. human life is at risk”. 

So why should we take care of plants?

“Some plants may be very rare or particularly beautiful. So it could be argued we have a duty to preserve them. They also give people enjoyment in national parks. Activists are highly motivated to protect the rainforest for this reason.”

In the video below Professor Katherine Willis (The Oxford Martin School) explains more about why the different plants and natural landscapes are so important to us and all life on Earth. 

But it's not that simple...

People who live in or near the rainforest may argue they need to chop some of it down to build homes, create jobs and earn a living to provide for their families. Do people in the developed world have the right to demand that people in the developing world don’t build over their natural environments?

“Some land is considered sacred by native Americans or Australians. It isn’t possible to preserve everything but respecting the wishes of people whose ancestors once occupied a land is something we ought to think about,” says Joshua. 

There’s a similar argument about destroying areas of natural beauty or of special scientific significance to build a new road, train line or runway. Those in favour tend to argue such developments benefit everyone as they bring jobs and money to the area. And maybe make it easier to get to work or fly abroad on holiday. But unless local people feel a direct benefit, the loss of a much-loved beauty spot can be devastating. 


“There is some evidence of plants demonstrating long term memory and learning. For example in an experiment people dropped plants to see how they reacted. It was seen that this damaged parts of their internal system. They then withdrew their leaves in reaction. But over time they were seen to adapt and grow back again. Also roots of trees and plants will search out and find water needed for nourishment but that doesn’t mean they function the way humans do. Plants have internal functioning mechanisms but this is nothing like a human or animal brain,” says Joshua. Some people argue that just because a living organism doesn’t function the same way we do is no excuse for not respecting its right to life. There needs to be balance between competing needs. 
Diverse plant life is vital for our existence. It provides everything we need for life on earth. However there are enormous pressures on our ecosystem from global warming and land-use change (such as mining for coal and precious materials, drilling for gas or oil (‘fracking'), and building new homes). And we should perhaps value plants and trees for their own right to life. “It’s all about managing conflict when different values and needs are in tension,” concludes Joshua.

Can you think of ways to treat plants fairly while thinking of human needs too? It’s a tricky one…

Plants help humans to survive - sometimes very literally…

Plants help humans to survive - sometimes very literally…

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8 plants that have helped us treat diseases

  1. Foxgloves (Digitalis)
    1. An extract from the beautiful woodland foxglove plant leaves, digitalis is a cardio-active drug; in other words, it acts on the heart and regulates the heartbeat. It was first discovered in 1775 by a doctor, William Withering, when a patient with a heart condition came to him, but could not be treated. The patient went to a gypsy who healed him, and when Withering heard this, he tracked the gypsy down and found out her secret remedy – foxglove extract! When Withering died, his friends carved a bunch of foxgloves on his headstone. Purified digitalis is now used in heart conditions, but has to be carefully dosed, as the lethal dose is close to the very small therapeutic dose. The extract was also used in the dark ages for the justice system of “trial by ordeal”, where the criminal was subjected to some painful or dangerous experience, and if they survived, they were innocent.
  2. Cinchona tree (Quinine)
    1. The Spanish discovered in the 17th century in what is now Peru that the bark of the cinchona tree was used by the indigenous people to cure “fevers”, especially malaria. At that time the European “treatment” for malaria was to throw the feverish patient head first into a bush and they had to get out quickly enough to leave the fever behind! Quinine was purified from bark extracts in 1820, and it was found that it could prevent as well as treat malaria. It was an essential tool in the spread of the British Empire around that time. Colonists in regions like India had to take daily doses of quinine, and eventually started mixing it with soda and water to make the bitter powder taste better, and “tonic water” was born. It wasn’t long before the daily dose of quinine in tonic water seemed much better mixed with gin, and the quintessential gin and tonic was used thereafter by colonists to stay safe in the hot, humid environments they were living in. Quinine is also used to treat lupus and arthritis.
  3. Coca plant (Cocaine) 
    1. This highly addictive drug, used nowadays as a recreational drug, has been used by indigenous South American people since ancient times as a stimulant and for its hunger-suppressing properties. They would chew the leaves of the coca plant or make tea infusions to give them strength and energy. After the Spanish arrived in South America, where most coca plants grow, they quickly realised its useful properties and began shipping the leaves to Europe, where Friedrich Gaedcke isolated the cocaine alkaloid from the leaves. The pain-killing and numbing properties of the drug meant it could be used in surgery, as well as for ailments such as headaches, aches and pains, depression and indigestion. Famously, Sigmund Freud became addicted to the drug after he tried to help a friend cure his morphine addiction by using cocaine. The friend died a broken man, a cocaine and morphine addict. An associate of Freud’s even proved its numbing properties by putting some cocaine solution in his eye and then pricking it with pins! And of course, cocaine used to be included in Coca Cola. Cocaine is not used much medically nowadays, apart from as a numbing agent for painful procedures in the mouth and nose.
  4. Madagascar periwinkle (Vincristine)
    1. A beautiful pink flower from the island of Madagascar, off the east coast of Africa, the “rosy periwinkle” as it is commonly known, was long used by traditional healers for diabetes, and in Chinese traditional medicine to treat diabetes, malaria and Hodgkin’s lymphoma, a type of blood and lymph cancer. In the 1950s two compounds from the plant were isolated – vincristine and vinblastine – which were found to have anti-cancer properties. Since the 1960s, these drugs have been used to treat blood cancers and have improved survival rates from 1 in 5 to 9 in 10! It takes 900 kg to make just one gram of the drug though, so pharmaceutical companies had to cultivate the plants on a large scale. Nowadays, however, vincristine and vinblastine are made synthetically.
  5. Meadow saffron (Colchicine)
    1. Also known as “naked lady”, meadow saffron produces a chemical called colchicine, used to treat gout, a kind of arthritis caused by a build-up of uric acid crystals in the joints. The joints become red, hot and swollen. The drug is also used to treat a type of genetic inflammatory disease called familial Mediterranean fever, where symptoms include swelling of large joints, stomach pain, and inflammation of the lining of the lungs, making it difficult to breathe or lie flat. Nobody really knows how the drug works, but it does. It was first described as a treatment for rheumatism and swelling on an Egyptian medical papyrus in 1500 BC. It was first used as a treatment for gout in the first century AD, but the drug was only isolated from the plant by two French chemists in 1820. Side effects include numbness and tingling of the hands and feet, and overdose causes burning in the mouth and throat, fever, vomiting and diarrhoea. This demonstrates the powerful actions that some plants can have on the body, and why it is so important to preserve the plants we have in case we discover more medicines.
  6. Willow (Aspirin)
    1. The active ingredient in aspirin is called acetylsalicylic acid, and it comes from the leaves (or bark) of the white willow tree. Aspirin has been around for centuries for the treatment of pain, fevers, inflammation, and even those who have had a heart attack. It reduces pain and inflammation and also thins the blood. It has even been used to reduce the risk of getting cancer and dying from cancer, mostly colorectal cancer. The use of willow leaf extracts has been known since ancient times, when the benefits were inscribed on clay tablets in ancient Egypt, and it has been a major boon to the medical world. Unfortunately, some side effects are ulcers in the stomach and using it way too much can cause deafness. One interesting fact about aspirin was its effect on the son of the last czar of Russia, Alexei Nicholaevich Romanov, who had haemophilia, a blood-thinning disease. Since aspirin thins the blood, which is why it is useful for heart attacks, it made his haemophilia worse. The mystic Rasputin suggested he should rely on spiritual treatments, not modern medicine, and Rasputin’s influence on the family is said to have led ultimately to the uprising against the czar, and the end of czarist Russia. 
  7. Rauwolfia serpentina (Reserpine) 
    1. Reserpine, a drug isolated from the roots of the smooth-stemmed herb Rauwolfia serpentine, is a very effective medication used to treat hypertension (high blood pressure) and psychotic disorders. The plant has been used in India for 4000 years as a treatment for snake and insect bites, malaria, abdominal pain, and dysentery. Even Mahatma Gandhi used to take Rauwolfia tea as a way to relax in the evenings. It is also said to have anti-depressive properties. Reserpine was first isolated in 1952, but unfortunately, despite its great success as a blood pressure drug, its use has been phased out because of interactions and side-effects, which include a stuffy nose, nausea, dizziness, vomiting, stomach cramps, and even, unexpectedly, depression! 
  8. Belladonna (Atropine)
    1. The nightshade family of plants, including deadly nightshade and mandrake (both famous for their use by witches in medieval times), produces the chemical atropine. For centuries the plants were used to treat wounds, gout and sleeplessness, pain and inflammation, and even as a love potion! Witches included it in hallucinogenic potions. In the middle ages, women used extracts of belladonna (deadly nightshade, literally “beautiful woman”) in their eyes to dilate the pupils, as this was regarded as attractive. Nowadays, atropine is used to treat nerve agent and pesticide poisoning, or a slow heart rate. Soldiers in chemical warfare zones carry atropine injectors in case they get poisoned.

Although there are tens of thousands of plants on the earth, 90% percent of the foods we eat come from just 30 plants.

Although there are tens of thousands of plants on the earth, 90% percent of the foods we eat come from just 30 plants. 

But do we think plants are important enough to actually change some of our habits?

But do we think plants are important enough to actually change some of our habits?

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6 ways we could change our lifestyles to help the environment

  1. No more ice cream? 
    1. From ice cream and margarine to shampoo and lipstick, Palm Oil is everywhere. It’s in about half of all packaged products at the supermarket, and makes things more ‘creamy’ – but at what cost? The Oil Palm Tree only grows in the tropics, and was originally grown in West Africa on small-scale family farms. As demand for processed food and make-up has grown, demand for Palm Oil has too. Now it’s grown in huge plantations mostly in Indonesia and Malaysia. Lots of tropical forests have been cleared to make way for these plantations. In Southeast Asia, 45% of plantations used to be tropical forests. Tropical forests are home to some of the most precious and diverse plants and animals on our planet. Plus, our use of Palm Oil is going up – putting more and more forests at risk. So should you give up ice cream? It’s not quite that simple. Not all ice cream contains Palm Oil (some contain corn or rape seed oil instead), and some will contain Palm Oil that’s sustainably sourced. Just take a look at the label to find out. Though if you do decide to quit Palm Oil, it’s likely that the alternative will be more expensive. Is that a price you’re willing to pay?
  2. No more holidays?
    1. Flying abroad produces a lot of GHG emissions. It’s not easy to work out, but roughly 100 g of CO2 is produced for each kilometre you fly. For a return flight from London to Rome that’s about 300 kg of CO2. Although planes have become cleaner as technology has improved, we’re flying more and more. As a result, GHG emissions from flights in Europe increased by 87% between 1990 and 2006. A number of companies now offer ‘carbon offsetting’ against flights. You can pay for a company to plant trees or invest in renewable energy to ‘balance out’ the CO2 produced by your flight. But maybe it’s better just not to fly at all? You could try using a more environmentally friendly form of transport e.g. electric trains? Or perhaps you can try to persuade your family to take holidays closer to home?
  3. No more burgers?
    1. Producing meat requires a huge amount of energy and releases damaging greenhouse gases (GHG). These GHGs contribute to global warming – with negative effects on plants and whole ecosystems. But why is meat so bad for the environment? It’s all to do with efficiency. To produce meat, we need space to rear the animals and space to grow plants (or other plants) to feed them until they’re big enough for slaughter. Large areas of forest have had to be cleared to make way for this type of farming, which has destroying the natural habitats of plants and wildlife across the world. Plus, not to forget, the pollution created when transporting the animal food and animals themselves. So should you give up burgers? Or even give up meat, eggs and dairy and go fully vegan? The choice is yours. But reducing the amount of meat you eat can definitely reduce your impact on the environment. It is predicted that if we all adopted a mostly vegetarian diet, we could cut food-related GHG emissions by 63%.
  4. Switch it all off!
    1. What about switching off your laptop? Or your TV? Or just remembering to turn off the lights? 
      Most of UK electricity is produced by burning fossil fuels – in coal, gas and oil-fired power plants. And all of this releases damaging greenhouse gases. Making small changes to reduce your energy use can all add up. Turn off lights, take shorter showers, turn off your laptop and your TV. It’s important to remember that lots of devices use energy even when they’re in power-save mode.
  5. Should I eat organic fruit and veg? 
    1. What does organic actually mean? Organic food is produced by using fewer chemicals. Instead of chemicals, organic farmers rely on more natural methods like weeding and spreading manure to produce good crops. Choosing organic fruit and veg could help reduce your impact on the environment – particularly the plant life and ecosystems in rivers and lakes. The chemicals used by non-organic farmers to produce bigger and better crops can run-off into rivers and lakes and lead to 'eutrophication'. This means the water has too many nutrients, so algae blooms and less sunlight reaches other plants. The end result can be the death of many plants and fish. Reducing the amount of chemicals in our water sounds like a great idea, and choosing organic food can help. But it’s not so simple. Organic farming produces less food per square mile of land – as it’s less efficient. With a growing population and more mouths to feed, can we afford to feed everyone organically?  
  6. Should I cycle to school?
    1. Do you normally get a lift in the car to school? Perhaps you have friends who do? Or maybe you take a lift in the car at weekends? Petrol and diesel cars are doubly bad. Not only do they release GHGs which lead to climate change, but burning petrol and diesel also releases pollutants like nitrogen oxides and sulphur dioxides. These pollutants can react in the atmosphere and lead to acid rain which can destroy plants (and animals and even some buildings). These pollutants are also bad for human health, so some cities are looking at becoming car-free in the not-too-distant future. Cycling to school instead of driving seems like the perfect solution. Cycling is good for the environment and your health. But it’s not always safe. If cycling isn’t an option, maybe you could take the bus or train? Or car-share with a friend? All these alternatives should reduce your impact on the environment. 

Thinking we’re more important than plants and not treating them well has led to global warming… or has it?

Thinking we’re more important than plants and not treating them well has led to global warming… or has it?

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7 scientists that say we’re not responsible for global warming

About 97% of climate scientists agree that global warming is real and that we (humans) are mostly to blame. But who doesn’t agree? There’s several researchers out there who challenge the theory– but not many of them are technically experts in climate science. Here, we take a look at seven climate sceptics…

  1. Dr David Evans
    1. Dr David Evans is an Australian mathematician and engineer who worked for the Australian Greenhouse Office and Department of Climate Change for several years. There, he created a program which predicts Green House Gas emissions from Australia’s forests and farms. He believes that CO2 only has a small warming effect. He says he can be sure of this because there’s no evidence of a ‘hot spot’ 10 km up in our atmosphere. Because he thinks CO2 isn’t very important, he thinks that our predictions of future global warming are wrong. He even suggests that the current models might over-estimate future warming by up to ten times!
  2. Prof. Freeman Dyson
    1. Freeman Dyson spent most of his life as a Professor of Physics at Princeton University and so he’s not a climate scientist in the traditional sense. He agrees that the amount of CO2 in the atmosphere is increasing. But he argues that this CO2 does “more good than harm”. He explains that the Earth is growing greener with more CO2 because it increases plant growth by warming the planet and increasing rainfall. More plants means more food crops and forests – which he says must be a good thing for the planet. What do you think? Could climate change actually be helpful to us? 
  3. Dr Judith Curry
    1. Dr Curry was a professor at the School of Earth and Atmospheric Sciences at Georgia Tech for over 10 years. But she retired recently– fed up with the ‘craziness’ of climate science. Dr Curry agrees that the Earth is warming and she was actually one of the first climate scientists to link hurricanes to global warming. However she isn’t convinced that we’re to blame for the warming. She’s also not convinced that the planet will warm as much as some people think, and she’s not sure it will be dangerous.  She thinks everyone’s too focused on Greenhouse Gas emissions (GHGs) and have ignored the effect of natural variation in the climate. She’s convinced that natural forces play a much bigger role than GHGs.
  4. Prof. Ivar Giaever 
    1. Prof. Ivar Giaever is a retired professor of physics (Rensselaer Polytechnic Institute), and in 1973 he joint-won the Nobel Prize for the discovery of something called electron tunnelling in superconductors. Although climate science isn’t Prof. Giaever’s area of expertise, he has some strong opinions. He has said that global warming is a “non-problem” and that we should stop “wasting huge… amounts of money on global warming” because temperatures haven’t increased by that much anyway. He even suggests that maybe it’s all the paved roads and cutting down of forests which cause global warming. In 2011 he resigned from the American Physical Society because he disagreed with their statement on man-made global warming. 
  5. Dr Don Easterbrook
    1. Dr Don Easterbrook is a geologist and professor at Western Washington University in America. He doesn’t just disagree with man-made global warming, but he also disagrees that the planet is warming at all. Instead he thinks the data - that shows warming - has been messed around with, and believes that what we’re actually going through is global cooling! He says the Earth has been cooling since 1998, that the ice sheets are growing, and that CO2 is unable to cause global warming. As for the future, he thinks that the next 25 – 30 years will be cooler, not warmer. 
  6. John Casey
    1. John Casey has a background in physics and maths and used to advise the White House on the space program. He also worked for NASA. However, he is probably most well-known for writing a book called 'Cold Sun'. The book focuses on ‘global cooling’. He believes that the Earth’s climate is mainly controlled by the Sun, and that CO2 emissions don’t lead to global warming. In fact, he's looked at the Sun’s activity and concluded that the Earth is in a solar cycle which will lead to global cooling for the next 30 years or so. Rather than worrying about global warming, he says we should all be nervous about future cooling of the Earth.
  7. Piers Corbyn
    1. Piers Corbyn has qualifications in physics and Astrophysics. But weather (or meteorology) is his passion. He’s made it clear that he believes there’s no such thing as man-made climate change, and like lots of other climate sceptics he thinks the world is cooling instead. He believes that solar (or Sun) activity plays a key role in both the Earth’s long-term climate and seasonal weather. He even predicts weather by looking at the Sun’s activity and patterns from history. This approach is very different to most other weather forecasters - but Corbyn is so sure of his methods that apparently he’s bet money on them before!

Plants were on the earth long before humans - let’s look at how we’ve shared the space…

Plants were on the earth long before humans - let’s look at how we’ve shared the space…

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The human takeover

This short animation explores the development of cities across 10,000 years. Vance Kite (North Carolina State University) looks at how our cities came about in the past and predicts how we can expect future cities to adapt to our growing populations.