Just how bad is eating meat for the planet?

‘One person not changing off a meat heavy diet won’t make a difference.’ – 7.6 billion people

More and more people are becoming concerned about what affects their diet has on the planet and other people. Last year, doctors Poore and Nemecek from the University of Oxford compiled data from over 500 published papers to understand just how bad the food industry is for the planet, which parts are the worst and what can be done about it.

Recent science articles reveal some astonishing and shocking statistics of the impact our food, and particularly meat intake has on our Earth:

  • Agriculture contributes to a quarter off all human greenhouse gas emissions.
  • 14.5% of this is from livestock alone.
  • Agriculture is the biggest single threat to biodiversity.
  • Livestock takes up 83% of agricultural land, yet only provides 37% of our protein and 18% of our calorie intake.
  • Agriculture uses more freshwater than any other human activity, of this, livestock uses the most.

So if you thought the impact of the food industry is trivial, think again. It has impacts far exceeding animal rights, into global biodiversity, human societies and now the global climate. Even if you couldn’t care less about the planet and what lives there, a transfer off a meat diet would free up 3.1 billion hectares of space, to be used for other things. Moreover, as i explain here, livestock is uses four times as much antibiotics as humans, which is building up a resistance set to cause more human deaths than cancer by 2050. (https://swiftscience971095579.wordpress.com/2019/05/11/antimicrobial-resistance-is-not-a-scare-story-its-happening-the-world-health-organisation-warns/)

The other thing many people suggest is that changing their diet won’t have a big impact. However, Poore and Nemecek ran a scenario where humans completely stop meat intake and found we could:

  • Reduce land use from food by 76%
  • Reduce greenhouse gas emissions by 49%
  • Reduce freshwater use by 19%

As i will explain in a following article, there are also major health benefits from switching to a meat free diet, so really its a win-win-win. So it does make a difference transferring off a meat heavy diet and it is important, so it’s time to stop.

‘One person not changing off a meat heavy diet won’t make a difference.’ – 7.6 billion people

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The most extreme life on Earth part three: the great deep sea farmers

In the abyss of the deep, vents provide energy for an oasis of incredible and bizarre life.

The bottom of our oceans are a black expanse of nothingness for hundreds of kilometers in each direction. Yet in the darkness of the deep sea desert, hydrothermal vents provide a spectacular oasis, as densely populated as most ecosystems on land, boasting an array of the strangest animals on the planet.

In the deep abyss, you have to deal with crushingly high pressures, low and high temperatures but most of all, an absence of energy. About a kilometre down there is no light and without photosynthesis, or basically anything else, finding an energy source is like finding a needle in a haystack.

The vents provide energy by constantly pumping superheated water (up to 400oC, as at high pressures the boiling point of water increases), which have previously gathered minerals in the rock below.

Large animals can’t use this chemical energy directly, but incredibly they literally farm microbes which can.

Tube worms (above and below) can grow to a massive 3 meters long, and they are gross. Perhaps the weirdest thing about them isn’t the fact that they look like a garden worm on steroids, but that they don’t have an anus. Instead, they gather their excrement in a sac, which slowly fills up and poisons them until they die. More remarkable still, their farming of microbes has gone so far that they have replaced their digestive tract with their livestock. Infact, half of the body weight of a tube worm is pure microbes, constantly using the hydrogen sulphide to provide the worm with energy.

The tube worm outside its shell showing the sac which slowly fills up with its own excrement.

Pompeii worms are equally as bizarre, but farm their microbes in a more traditional sense (kind of). They harbour the livestock on their back, let them grow and then let other worms feed on them. Vent shrimps do something similar, growing microbes on their body, but instead of letting others harvest them, they wait until they shed their skin, and then eat their old carcass.

A Pompeii worm

Considering these crazy creatures have been farming for millions of years, and we only started 12,000 years ago, maybe they’ve beaten us other things? If we look further maybe they’ve got little cars and record players, and are studying humans in tiny, deep sea laboratories.

Plenty more fish in the sea: the remarkable conservation success in the Gulf of California.

Biodiversity is flourishing the the Gulf of California since a conservation programme started.

Fish consumption has more than doubled in the last 50 years, leading to the over-fishing of a third of the worlds stocks. As a result, 90 species are at risk from extinction, including 40% of sharks and rays, which are important in ecosystem functioning.

It is easy to forget that fishing is not farming, it is hunting. On land, any animal that has ever been hunted for food has gone extinct. Luckily, the ocean is humongous and relatively inaccessible, so we still have a chance to protect our fishy friends from the same fate.

In the Gulf of California, Cabo Pulmo National Park was set up in 1995 and enforced a community based ‘no take’ zone, banning all fishing. Scientist Aburto-Oropeza studied the fish community in 1995, 1999 and then again in 2009.

After the first check up, they were disappointed to learn that the fish stocks hadn’t changed. You can imagine the excitement then, when ten years later fish biomass had increased by a ridiculous 463%, corals were thriving and sharks had started to patrol the ocean once more. Incredibly, the fish population had exploded so much that there was over-spill into surrounding area, boosting the yields of local fishermen.

However, these ‘no take’ zones only cover less than a percent of our oceans as it takes long term commitment and cooperation. Moreover, some of these have failed, due to a ‘top-down’ approach, where large companies have failed to use local expertise and reliable conservation methods to recover fish communities.

In any case, in a world where any environmental story is seemingly doom and gloom, it is nice to see a positive one!

The most extreme life on the planet part two: living for 250 million years.

Could a microbe (arrow) live inside a salt crystal for 250million years?

On the turn of the millennia, Russell Vreeland released an incredibly controversial paper, in which he claimed they had found a microbe that had been alive for 250 million years. That’s your life, 30000000 times. More remarkable still, the microbe had survived inside a salt crystal (above).

Originally, it was received with a great deal of caution in the scientific community, as no-one thought life could persist that long, even if in suspended animation, let alone active and growing. After all, how do you get energy to grow for a quarter of a billion years?

Since then, another scientist, Brian Schubert, devised a more robust experiment, suggesting that microbes can live off the glycerol produced by just one cell of green algae for 12.5 million years. The glycerol would provide energy for cell repair whilst preventing dehydration and protein damage.

It is not beyond the realms of possibility then, that life could persist for 250 million years, or even longer. Could Vreeland have been right all along? In a booming scientific field, the race is on to find out.

Extreme life part one: volcanoes:https://swiftscience971095579.wordpress.com/2019/04/21/the-most-extreme-life-on-the-planet-part-one-life-in-volcanos/‎(opens in a new tab)

To understand how long 250 million years read: Feel old yet? Understanding just how ancient Earth is: https://swiftscience971095579.wordpress.com/2019/04/10/feel-old-yet-understanding-just-how-ancient-earth-is/‎(opens in a new tab)

Are we creating a ‘super weed’, and how scared should we be of herbicide resistance?

Roundup is the most common herbicide, but will it work for much longer?

Weeds cost the U.S economy a whopping 30 billion dollars a year by competing for our crop’s nutrients, but are in a constant and gruelling fight for survival with herbicides. These herbicides kill the weeds, increasing yields by a third. The fear is that weeds will become resistant, creating ‘super weeds’, and with three billion more people to feed in thirty years, will be a serious threat to food security. But how likely is this, and should we be worried?

Well, herbicide resistance is happening, all the time in fact. By slightly altering the shape of their proteins, weeds can avoid the toxic herbicide, and if the genes for that protein spreads into the next growing season, will compete with the crop for nutrients and reduce yields.

The response of farmers is simple: rotate the different kinds of herbicides and the weeds won’t be able to react in time. However, Dr Christophe Delye is concerned that herbicide rotation might work in the short term, but could promote long-term resistance to not one but all herbicide types.

Farmers often rotate their herbicides to kill weeds like these ones.

He explains that herbicides work by targeting a specific part of a weed, say, the amino acids. Until recently, we thought that the response of the weed was equally specific, altering just the targeted amino acid. The reality however, is that when stressed, the weeds exhibit a range of responses, on multiple parts of multiple genes and in doing so, gaining a slight resistance to all herbicides.

Keep doing this and eventually the ‘super weed’ will be able to avoid every toxic herbicide we throw at them.

So should we be worried? Although the chances of a dystopian and barren landscape in 50 years is unlikely, we already have so many worries in the food system (see links below), that reduced yields from herbicide resistance simply cannot be allowed.

Is the choice between agriculture and biodiversity really an ultimatum? https://wordpress.com/block-editor/post/swiftscience971095579.wordpress.com/139

Multi-billion pound American companies deliberately cause famine in Malawi to increase their profits. https://wordpress.com/block-editor/post/swiftscience971095579.wordpress.com/87
The Soil we Live on is Disappearing and it is YOUR Responsibility. https://wordpress.com/block-editor/post/swiftscience971095579.wordpress.com/55

The most extreme life on the planet. Part one: life in volcanos.

Yellowstone National Park, with each ring of colour due to a different microorganism.

For all its beauty, Yellowstone National Park is a terrifying place. If it erupted tomorrow, most of America would be drowned in ash, and they wouldn’t see sunlight for weeks. Add extreme pressures, no nutrients and oxygen depletion to the searing heat in volcanic pools and you can understand why we used to think life here was impossible.

However, those amazing dashes of red, green and yellows sweeping across the volcanic pools are not from the rocks but from microbial life which aren’t just tolerating the scorching heat, but need it to survive.

Apart from being a liiitle bit painful, if I jumped in the pool and tried to survive, my cell membranes would crumble, my enzymes and proteins would melt and my DNA simply unravel and fall apart. How is it then, that at 115°C we still find archaea (single celled organisms which are as different from bacteria as we are)?

To survive and grow, these archaea have ultra strong membranes to stop the cell from melting. Weirdly, they then pump salt into their cells, acting as a clamp to hold the protein and DNA structures together, so they don’t fragment. For food the ingenious and complicatedly named Sulfolobus acidocaldarius actually sticks and clings onto sulphur crystals and uses the hydrogen sulphide to gather energy.

Nothing so far has been found above 120°C as it is thought any large molecules will simply fall apart. But, we have been wrong before.

As an aside to why you should care, the first ever life, which has given rise to you, me and everything living almost definitely lived in a deep sea volcano. Furthermore, the enzyme used to replicate DNA and sequence entire genomes was isolated from a bacteria living in a volcano.

If you are interested, I will be writing about various extreme life in the near future, including life in space, other planets, inside ice, rocks and salt and will be asking whether it is possible for an organism to live for 250 million years.

The advent of complex life. Why wait 4 billion years?

An artistic impression of life after the Cambrian explosion

As I explain in a previous post (https://wordpress.com/block-editor/post/swiftscience971095579.wordpress.com/124), the Earth is extraordinarily old. Yet remarkably, complex life has only been thriving for 10% of its incomprehensibly long 4.54 billion year existence.

When life began, it was confined to simple, single celled organisms in microbial mats, locked in an apparent stasis. Then, at some perplexingly arbitrary point, one cell engulfed another and formed a beneficial relationship that sparked an explosion (named the Cambrian explosion) of intricate life, morphing and evolving for 540 million years before eventually ending with us and everything else living.

For a long time, scientists couldn’t understand why the world had such a long and arduous 4 billion year wait for complex life. Afterall, becoming multicellular and elaborate comes with a major evolutionary advantage: you can become mobile and feed on other organisms.

Some scientists postulate that there must have been some adaptation that was advantageous, and multicellular life kicked off from there. However, this all seemed too random and Dr Erik Sperling explains how scientists now believe complex life was limited by low oxygen levels.

Before the explosion of life, oxygen levels were only a fraction of today’s. Place a modern fish in these conditions and it would quickly die. Oxygen is the most efficient molecule to use in respiration and without it, your maximum energy consumption is massively reduced. In this regard, with such little oxygen, elaborate organisms simply wouldn’t have enough energy to survive.

It should be of little surprise then to learn that at the cambrian explosion, oxygen levels rose to 0.5ml/L, just enough, Sperling suggests, to harbour complex life.

Once complex life started in the Cambrian, it proliferated at an astonishing rate and quickly formed an array of creatures including a spiky slug, a five eyed Opabinia, jellyfish and predators with finger like suction pads and rows of teeth (figure above).