Water Science

This afternoon, the kids and I helped with some citizen science as part of the Thames WaterBlitz, a collaborative effort to sample water quality of the rivers, canals, and ponds of the Thames Valley to produce valuable data for the researchers of today and tomorrow.

Annabel fetches water from the canal.
Our sampling point was by bridge 228 on the Oxford Canal: the first job was fetching water.

My two little science assistants didn’t need any encouragement to get out of the house and into the sunshine and were eager to go. I didn’t even have to pull out my trump card of pointing out that there were fruiting brambles along the length of the canal. As I observed in a vlog last year, it’s usually pretty easy to motivate the tykes with a little foraging.

Annabel and John assess the colour of the canal water.
Some collaboration was undertaken to reach a consensus on the colour of the sample.

The EarthWatch Institute had provided all the chemicals and instructions we needed by post, as well as a mobile app with which to record our results (or paper forms, if we preferred). Right after lunch, we watched their instructional video and set out to the sampling site. We’d scouted out a handful of sites including some on the River Cherwell as it snakes through Kidlington but for this our first water-watch expedition we figured we’d err on the safe side and aim to target only a single site: we chose this one both because it’s close to home and because a previous year’s citizen scientist was here, too, improving the comparability of the results year-on-year.

Chemistry experiments on the banks of the Oxford Canal.
Lots of nitrates, as indicated by the colour of the left tube. Very few phosphates, as indicated by the lack of colour in the right (although it’s still a minute and a half from completing its processing time at the point this photo was taken and would darken a tiny bit yet).

Plus, this expedition provided the opportunity to continue to foster the 5 year-old’s growing interest in science, which I’ve long tried to encourage (we launched bottle rockets the other month!).

Annabel compares her sample to the colour chart.
Which colour most-resembles the colour of our reagent?

Our results are now online, and we’re already looking forward to seeing the overall results pattern (as well as taking part in next year’s WaterBlitz!).

The man who made Einstein world-famous

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It is hard to imagine a time when Albert Einstein’s name was not recognised around the world.

But even after he finished his theory of relativity in 1915, he was nearly unknown outside Germany – until British astronomer Arthur Stanley Eddington became involved.

Einstein’s ideas were trapped by the blockades of the Great War, and even more by the vicious nationalism that made “enemy” science unwelcome in the UK.

But Einstein, a socialist, and Eddington, a Quaker, both believed that science should transcend the divisions of the war.

It was their partnership that allowed relativity to leap the trenches and make Einstein one of the most famous people on the globe.

I hadn’t heard this story before, and it’s well-worth a read.

The Side Effects of Vaccines – How High is the Risk?

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Kurzgesagt tells it like it is. The thing I love the most about this video is the clickbaity title that’s clearly geared to try to get the attention of antivaxxers and the “truth teaser” opening which plays a little like many antivaxxer videos and other media… and then the fact that it goes and drops a science bomb on all the fools who tout their superstitious bollocks. Awesome.

Alka-Seltzer added to spherical water drop in microgravity

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This is just…wooooah. Proper “dude, my hands are huge” grade moment, for me, when I watched the bubbles form in the droplet of water. I had an idea about what would happen, and I was partially right, but by the time we were onto the third run-through of this experiment I realised that I’d been seeing more in it every single time.

Microgravity is weird, y’all.

The 500-Year-Long Science Experiment

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The 500-Year-Long Science Experiment (The Atlantic)

In 2014, microbiologists began a study that they hope will continue long after they’re dead.

In the year 2514, some future scientist will arrive at the University of Edinburgh (assuming the university still exists), open a wooden box (assuming the box has not been lost), and break apart a set of glass vials in order to grow the 500-year-old dried bacteria inside. This all assumes the entire experiment has not been forgotten, the instructions have not been garbled, and science—or some version of it—still exists in 2514.

This is a biology experiment that’s planned to run for half a millenium. How does one even make such a thing possible?

Thinking about the difficulties in constructing a message that may be understood for generations into the future reminds me of the work done on a possible marking system for nuclear waste disposal (which would need to continue to carry the message that a place is dangerous for ten thousand years).

This kind of philosophical thinking may require further work, though, if we’re ever to send spacecraft on interstellar journeys: another kind of “long” experiment. How might we preserve the records of what we’ve done, so that our descendants have the opportunity to continue our work, in a way that promotes the iterative translation and preservation of the messages that are required to support it? For example: if an experiment is to be understandable if rediscovered after a hypothetical future dark age, what precautions do we need to take today?

Alpha-Gal and the Gaia Hypothesis

Ticking Point

An increasing number of people are reportedly suffering from an allergy to the meat and other products of nonhuman mammals, reports Mosaic Science this week, and we’re increasingly confident that the cause is a sensitivity to alpha-gal (Galactose-alpha-1,3-galactose), a carbohydrate produced in the bodies of virtually all mammals except for us and our cousin apes, monkeys, and simians (and one of the reasons you can’t transplant tissue from pigs to humans, for example).

Lone star tick
The lone star tick (You call that a star, tick? Looks like a blob to me!), one of several vectors for alpha-gal sensitivity.

The interesting thing is that the most-common cause of alpha-gal sensitivity appears to be the bite of one of a small number of species of tick. The most-likely hypothesis seems to be that being bitten by such a tick after it’s bitten e.g. deer or cattle may introduce that species’ alpha-gal directly to your bloodstream. This exposure triggers an immune response through all future exposure, even if it’s is more minor, e.g. consuming milk products or even skin contact with an animal.

That’s nuts, isn’t it? The Mosaic Science article describes the reaction of Tami McGraw, whose symptoms began in 2010:

[She] asked her doctor to order a little-known blood test that would show if her immune system was reacting to a component of mammal meat. The test result was so strongly positive, her doctor called her at home to tell her to step away from the stove.

That should have been the end of her problems. Instead it launched her on an odyssey of discovering just how much mammal material is present in everyday life. One time, she took capsules of liquid painkiller and woke up in the middle of the night, itching and covered in hives provoked by the drug’s gelatine covering.

When she bought an unfamiliar lip balm, the lanolin in it made her mouth peel and blister. She planned to spend an afternoon gardening, spreading fertiliser and planting flowers, but passed out on the grass and had to be revived with an EpiPen. She had reacted to manure and bone meal that were enrichments in bagged compost she had bought.

A delicious-looking BLT. Mmm, bacon.
Cats can eat bacon. But some cat owners can’t. More bacon for the cats? The plot thickens. Also: haven’t used this picture in a while, have I?

Of course, this isn’t the only nor even the most-unusual (or most-severe) animal-induced allergy-to-a-different-animal we’re aware of. The hilariously-named but terribly-dangerous Pork-Cat syndrome is caused, though we’re not sure how, by exposure to cats and results in a severe allergy to pork. But what makes alpha-gal sensitivity really interesting is that it’s increasing in frequency at quite a dramatic rate. The culprit? Climate change. Probably.

It’s impossible to talk to physicians encountering alpha-gal cases without hearing that something has changed to make the tick that transmits it more common – even though they don’t know what that something might be.

“Climate change is likely playing a role in the northward expansion,” Ostfeld adds, but acknowledges that we don’t know what else could also be contributing.

Meat Me Half-Way

To take a minor diversion: another article I saw this week was the BBC‘s one on the climate footprint of the food you eat.

BBC graph showing climate impact of common foods. Beef is terrible *unshocker*.
An average serving of beef contributes almost 8kg of greenhouse gases, compared to around 1kg for chicken. Thanks, Beeb (click through for full article).

A little dated, perhaps: I’m sure that nobody needs to be told nowadays that one of the biggest things a Westerner can do to reduce their personal carbon footprint (after from breeding less or not at all, which I maintain is the biggest, or avoiding air travel, which Statto argues for) is to reduce or refrain from consumption of meat (especially pork and beef) and dairy products.

Indeed, environmental impact was the biggest factor in my vegetarianism (now weekday-vegetarianism) for the last eight years, and it’s an outlook that I’ve seen continue to grow in others over the same period.

Seeing these two stories side-by-side in my RSS reader put the Gaia hypothesis in my mind.

SMBC comic frame: "Yeah, I don't buy it. If Earth is self-regulating and alive, why hasn't it produced an immune response against humanity?"
If you want a pop-culture-grade introduction to the Gaia hypothesis in the context of climate change, this SMBC comic does the job, and does so almost with fewer words than this caption explaining that it does so.

If you’re not familiar with the Gaia hypothesis, the basic idea is this: by some mechanism, the Earth and all of the life on it act in synergy to maintain homeostasis. Organisms not only co-evolve with one another but also with the planet itself, affecting their environment in a way that in turn affects their future evolution in a perpetual symbiotic relationship of life and its habitat.

Its advocates point to negative feedback loops in nature such as plankton blooms affecting the weather in ways that inhibit plankton blooms and to simplistic theoretical models like the Daisyworld Simulation (cute video). A minority of its proponents go a step further and describe the Earth’s changes teleologically, implying a conscious Earth with an intention to protect its ecosystems (yes, these hypotheses were born out of the late 1960s, why do you ask?). Regardless, the essence is the same: life’s effect on its environment affects the environment’s hospitality to life, and vice-versa.

There’s an attractive symmetry to it, isn’t there, in light of the growth in alpha-gal allergies? Like:

  1. Yesterday – agriculture, particularly intensive farming of mammals, causes climate change.
  2. Today – climate change causes ticks to spread more-widely and bite more humans.
  3. Tomorrow – tick bites cause humans to consume less products farmed from mammals?
Daisyworld in SimEarth
Both my appreciation and my rejection of Gaia Hypothesis can probably be traced to me playing way too much SimEarth as a teenager. Here’s my Daisyworld in state of equilibrium, because I haven’t yet gotten bored and spawned dinosaurs to eat all of the daisies.

That’s not to say that I buy it, mind. The Gaia hypothesis has a number of problems, and – almost as bad – it encourages a complacent “it’ll all be okay, the Earth will fix itself” mindset to climate change (which, even if it’s true, doesn’t bode well for the humans residing on it).

But it was a fun parallel to land in my news reader this morning, so I thought I’d share it with you. And, by proxy, make you just a little bit warier of ticks than you might have been already. /shudders/

The Case Against Quantum Computing

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Quantum computing is all the rage. It seems like hardly a day goes by without some news outlet describing the extraordinary things this technology promises. Most commentators forget, or just gloss over, the fact that people have been working on quantum computing for decades—and without any practical results to show for it.

We’ve been told that quantum computers could “provide breakthroughs in many disciplines, including materials and drug discovery, the optimization of complex manmade systems, and artificial intelligence.” We’ve been assured that quantum computers will “forever alter our economic, industrial, academic, and societal landscape.” We’ve even been told that “the encryption that protects the world’s most sensitive data may soon be broken” by quantum computers. It has gotten to the point where many researchers in various fields of physics feel obliged to justify whatever work they are doing by claiming that it has some relevance to quantum computing.

Meanwhile, government research agencies, academic departments (many of them funded by government agencies), and corporate laboratories are spending billions of dollars a year developing quantum computers. On Wall Street, Morgan Stanley and other financial giants expect quantum computing to mature soon and are keen to figure out how this technology can help them.

It’s become something of a self-perpetuating arms race, with many organizations seemingly staying in the race if only to avoid being left behind. Some of the world’s top technical talent, at places like Google, IBM, and Microsoft, are working hard, and with lavish resources in state-of-the-art laboratories, to realize their vision of a quantum-computing future.

In light of all this, it’s natural to wonder: When will useful quantum computers be constructed? The most optimistic experts estimate it will take 5 to 10 years. More cautious ones predict 20 to 30 years. (Similar predictions have been voiced, by the way, for the last 20 years.) I belong to a tiny minority that answers, “Not in the foreseeable future.” Having spent decades conducting research in quantum and condensed-matter physics, I’ve developed my very pessimistic view. It’s based on an understanding of the gargantuan technical challenges that would have to be overcome to ever make quantum computing work.

Great article undermining all the most-widespread popular arguments about how quantum computing will revolutionise aboslutely everything, any day now. Let’s stay realistic, here: despite all the hype, it might well be the case that it’s impossible to build a quantum computer of sufficient complexity to have any meaningful impact on the world beyond the most highly-experimental and theoretical applications. And even if it is possible, its applications might well be limited: the “great potential” they carry is highly hypothetical.

Don’t get me wrong, I’m super excited about the possibility of quantum computing, too. But as Mickhail points out, we must temper our excitement with a little realism and not give in to the hype.

The Scrotum Is Nuts

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Why are testicles kept in a vulnerable dangling sac? It’s not why you think.

Some of you may be thinking that there is a simple answer: temperature. This arrangement evolved to keep them cool. I thought so, too, and assumed that a quick glimpse at the scientific literature would reveal the biological reasons and I’d move on. But what I found was that the small band of scientists who have dedicated their professional time to pondering the scrotum’s existence are starkly divided over this so-called cooling hypothesis.

When I first saw this article and its clickbait subtitle, I almost didn’t read it. After all, I thought I knew the answer: that testicles hang outside the body (and in a sac with a large surface area) because this helps them to keep cool, which aids the production of sperm. It turns out that this is far from an established fact, and a significant number of biologists dispute it and/or subscribe to one of a number of alternate hypotheses. Read for yourself…

Einstein’s theory still passes the test: weak and strong gravity objects fall the same way

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Fabulous explanation of the Strong Equivalence Principle coupled with a nice bit of recent research to prove that it holds true even in extreme gravitational fields (and therefore disproving a few interesting fringe theories). It’s hard science made to enjoy like pop science: yay! Plus a Hitch-Hiker’s Guide to the Galaxy reference, to boot. Under 10,000 views; go show them some love.

Science! (for toddlers)

I’m not sure that there’s any age that’s too-young at which to try to cultivate an interest in science. Once a child’s old enough to ask why something is the case, every question poses an opportunity for an experiment! Sometimes a thought experiment is sufficient (“Uncle Dan: why do dogs not wear clothes?”) but other times provide the opportunity for some genuine hands-on experimentation (“Why do we put flowers in water?”). All you have to do is take every question and work out what you’d do if you didn’t know the answer either! A willingness to take any problem with a “let’s find out” mentality teaches children two important things: (a) that while grown-ups will generally know more than them, that nobody has all the answers, and (b) that you can use experiments to help find the answers to questions – even ones that have never been asked before!

Annabel sorts jewellery at the Pitt River Museum of Anthropology.
“Why do we make jewellery out of different things?” Thanks to the Pitt Rivers Museum for inspiring this question… and helping us to find an answer.

Sometimes it takes a little more effort. Kids – like all of us, a lot of the time – can often be quite happy to simply accept the world as-it-is and not ask “why”. But because a fun and educational science activity is a good way to occupy a little one (and remember: all it needs to be science is to ask a question and then try to use evidence to answer it!), I’ve been keeping a list of possible future activities so that we’ve got a nice rainy-day list of things to try. And because we are, these days, in an increasingly-large circle of breeders, I thought I’d share some with you.

Annabel observes the filling of a paddling pool with custard.
You don’t strictly need a cement mixer full of custard to demonstrate dilatant (non-Newtonian) fluids, but messiness is engaging all by itself.

Here’s some of the activities we’ve been doing so far (or that I’ve got lined-up for future activities as and when they become appropriate):

  • Measuring and graphing rainfall
    We’ve spent a lot of time lately taking about calendars, weather, and seasons, so I’m thinking this one’s coming soon. All we need is a container you can leave in the garden, a measuring jug, and some graph paper.
  • Experimenting with non-Newtonian fluids
    You can make a dilatant fluid with cornflower and water: it acts like a liquid, but you can slap it and grab it like a solid. Fine, very wet sand (quicksand!) demonstrates pseudoplasticity which also explains how paint ‘blobs’ on your brush but is easy to spread thin on the paper.
  • Magnets
    I’m really looking forward to the opportunity to play with magnets: we’ve started already with thanks to Brio wooden railway and talking about the fact that the rolling stock will attach one way around (and seem to jump together when they get close) but repel the other way around, and we’ve also begun looking at the fact that if you remove a carriage from the middle of a train the remaining segments are already correctly-aligned in order to be re-attached.
  • Different kinds of bouncy balls
    We’ve had fun before measuring how high different kinds of balls (air-filled rubber football, large solid rubber ball, skeletal rubber ball, small solid rubber ball) bounce when dropped from a stepladder onto a patio and talking about how ‘squishy’ they are relative to one another, and speculating as to the relationship between the two.
Red-spotted black ladybird.
Spotting different subspecies of ladybirds is a great springboard to talking about heritable characteristics and phenotypic variation. Snails are another good candidate.
  • Demonstrating capillary action/siphoning
    Two containers – one with a fluid in and one without – joined over the rim by a piece of paper towel will eventually reach an equilibrium of volume, first as a result of capillary action causing the fluid to climb the paper and then using a siphon effect to continually draw more over the edge.
  • Illustrating the solar system (to scale)
    It helps adults and children alike to comprehend the scale of the solar system if you draw it to scale. If you’ve got a long street nearby you can chalk it onto the pavement. If not, you’ll need a very small scale, but doing the Earth and Moon might suffice.
  • Electricity
    Batteries, wires, and LEDs are a moderately safe and simple start to understanding electricity. Taking a ‘dead’ battery from a drained toy and putting it into the circuit shows the eventual state of batteries. Connecting lights in series or parallel demonstrates in very simple terms resistance. Breaking or joining a circuit illustrates that switches function identically wherever they’re placed on the circuit.
  • Vortices
    I’m interested in trying to replicate this experiment into making different kinds of standing vortices in water, but I might have to wait until our little scientist has slightly more patience (and fine motor control!).
A demonstration of capillary action using water and tissue paper.
Water, tissue paper, and patience is all you need to demonstrate capillary action and siphoning. Food colouring’s an optional bonus.
  • Centripetal force
    We’ve been lucky enough to get to talk about this after using a whirlpool-shaped piece of marble run, but if we hadn’t then I was thinking we’d wait until the next time it was sunny enough for outdoor water play and use the fact that a full bucket can be spun around without spilling any in a similar way.
  • Bug counting
    Take a quadrant of garden and count the different kinds of things living in it. Multiply up to estimate the population across the garden, or measure different parts (lawn versus bedding plants versus patio, direct sunlight versus shade, exposed versus covered, etc.) to see which plants or animals prefer different conditions.
  • Growing plants
    Caring for different kinds of plants provides an introduction to botany, and there’s a lot to observe, from the way that plants grow and turn to face the light to the different stages of their growth and reproduction. Flowers give an attractive result at the end, but herbs and vegetables can be eaten! (Our little scientist is an enormous fan of grazing home-grown chives.)
  • Mechanics and force
    We’ve taken to occasionally getting bikes out of the shed, flipping them upside-down, and observing how changing the cogs that the chain runs over affects how hard you need to push the pedals to get movement… but also how much the movement input is multiplied into the movement of the wheel. We’re not quite at a point where we can reliably make predictions based on this observation, but we’re getting there! I’m thinking that we can follow-up this experiment by building simple catapults to see how levers act as a force multiplier.
Annabel and Ruth cooking.
Cooking provides opportunities for exploration, too. Bake some bread and you’ve got an excuse to talk about yeast!
  • Chromotography of inks
    I’ve been waiting to do this until I get the chance to work out which felt tip pens are going to give us the most-exciting results… but maybe that’s an experiment we should do together, too! Colouring-in coffee filter papers and then letting them stand in a cup of water (assuming a water-soluable ink) should produce pretty results… and show the composition of the inks, too!
  • Colour mixing
    Mixing paint or play-doh is an easy way to demonstrate subtractive colour mixing. We got the chance to do some additive colour mixing using a colour disk spinner at a recent science fair event, but if we hadn’t I’d always had plans to build our own, like this one.
  • Structure and form of life
    Looking at the way that different plants and animals’ physical structure supports their activities makes for good hands-on or thought-driven experimentation. A day at the zoo gets a few steps more-educational for a preschooler when you start talking about what penguins are able to do as a result of the shape of their unusual wings and a walk in the park can be science’d-up by collecting the leaves of different trees and thinking about why they’re different to one another.
  • Stabbing balloons
    The classic magic trick of poking a skewer through a balloon… with petroleum jelly on the skewer… lends itself to some science, so it’s on my to-do list.
Paining a colour wheel.
Subtractive colour mixing can be demonstrated by mixing paint. Colour and spin a wheel to demonstrate additive mixing.
  • Surface tension
    Water’s such a brilliant chemical because it’s commonplace, safe, and exhibits so many interesting phenomena. Surface tension can be demonstrated by ‘floating’ things like paperclips on top of the surface, and can be broken by the addition of soap.
  • Astronomy
    In the winter months when the sun sets before bedtime are a great time to show off stars, planets, satellites and the moon. Eyes or binoculars are plenty sufficient to get started.
  • Life cycles
    I was especially pleased when our nursery kept an incubator full of chicken eggs so that the children could watch them hatch and the chicks emerge. We’d looked at this process before at a farm, but it clearly had a big impact to see it again. Helping to collect eggs laid by my mother’s chickens helps to join-up the circle. Frogspawn and caterpillars provide a way to look at a very different kind of animal life.
  • Putting baking soda into things
    Different everyday kitchen liquids (water, vinegar, oil…) react differently to the addition of baking soda. This provides a very gentle introduction to chemistry and provides an excuse to talk about making and testing predictions: now that we’ve seen what cold water does, do you think that hot water will be the same or different?
Annabel is awed by the size of a tyrannosaurus rex skeleton.
“Why do some animals have sharp teeth and some have flat teeth?” was a question I posed. We found the answer together (and were wowed by the size of the T-rex skeleton behind the camera) at the Natural History Museum.
  • Bubbles and foams
    Blowing bubbles through different types of mesh (we just used different kinds of tea towels elastic-banded to the cut-off end of a plastic bottle) demonstrates how you can produce foams of different consistencies – from millions of tiny bubbles to fewer larger bubbles – because of the permeability of the fabric. And then we wrecked the last tea towel by adding food colouring to it so we could make coloured foams (“bubble snakes”).
  • Phase transition
    Start with ice and work out what makes it melt: does it melt faster in your hand or in a dish? Does it melt faster or slower if we break it up into smaller parts? If we ‘paint’ pictures on the patio with them, where does the water go? I’m also thinking about ways in which we can safely condense the steam (and capture the vapour) from the kettle onto e.g. a chilled surface. Once we’re at a point where a thermometer makes sense I was also considering replicating the experiment of measuring the temperature of melting snow: or perhaps even at that point trying to manipulate the triple point of water using e.g. salt.
  • Dissection
    Take apart the bits of a flower, or look in detail at the parts of a bone-in cut of meat, and try to understand what they’re all for and why they are the way they are.
  • What floats?
    Next time the paddling pool is out, I’d like to start a more-serious look at which things float and which things don’t any try to work out why. What might initially seem intuitive – dense (heavy-for-their-size) things sink – can be expanded by using plasticine to make a mixture of ‘sinking’ and ‘floating’ vessels and lead to further discovery. I’m also thinking we need to do the classic ‘raisins in a fizzy drink’ thing (raisins sink, but their rough surfaces trap the bubbles escaping from the now-unpressurised liquid, causing them to float back up to shed their bubbles).
Annabel hugs a goat.
Get some hands-on biology at your nearest petting zoo. No science in this picture, but plenty of hugging.

So there’s my “now and next” list of science activities that we’ll be playing at over the coming months. I’m always open to more suggestions, though, so if you’re similarly trying to help shape an enquiring and analytical mind, let me know what you’ve been up to!