Face/on

You might have noticed how I’m a low-key (*ahem*) LEGO fan, but only if you’ve really been paying attention, and it has been quite a while since I went on a Lego-nerd rant (hm, not really).

Anyway, this 86-year-old company, named for the Danish words for “play well” (“leg” and “godt”), is not only known for its iconic building block but also for its iconic minifigure:

Decomposed LEGO figure. Image from (1)

Unlike the building block, which has remained the same for decades (in fact, a current block will still click with a 60-year-old one), the minifigure has gone through some major changes. Between 1975 and 2010, there have been at least 3655 different minifigures, and in 2000 there was an estimated total of over four billion mini Lego people! Actually, according to some predictions, the total number of minifigures will surpass that of humans next week!

And I trust Randall Munroe’s math… Image from (2)

The first minifigure (1975) didn’t even have any moving parts. It wasn’t until three years later, when the familiar yellow smiley-faced figure came out (your friendly neighborhood cop), that the arms and legs could be moved:

1978 guy (right) says: “Hands up!”
1975 guy (left) says nothing, for he has no face. Image from (3)

This was also when the Lego minifigure hand shape was developed. It is very useful for holding Lego-things. However, is very inefficient when your trying to be sarcastic…

Image result for quotation hands lego gif

Throughout the years, the figures have gotten increasingly more complex. It started with the hair (early male minifigures wore hats until the hairpiece was designed in 1979), then the accessories arrived. Hats, bags, hand-held weapons, … the whole shebang. In the meantime, the outfits got more detailed. When licensed playsets started taking off near the turn of the millennium (the first Star Wars series hit the shelves in 1999), a whole franchise originated which would include books, video games, and animation films. More series soon followed, including Harry Potter, Batman, LOTR, … the list is endless. And while the outfits and accessories became more elaborate, the faces became more – well – emotional?

Initially, there was only the blank smile. Now, Lego minifigure faces encompass all the emotions. According to a 2013 paper, there are six main types of facial expressions: disdain, confidence, concern, fear, happiness, and anger.

Scorny, Gutsy, Worry, Scardy, Happy, and Grumpy. Dopey has gone missing. Image from (1)

Happy and angry faces are the most common, with the relative proportion of happy faces decreasing over time. In short, with an increasing emotional range, Lego minifigures seem to be getting more “human.” Soon, they’ll have Myers–Briggs personality types!

Over But for now, we’ll have to do with two-faced police officers…

Over time, Hollywood movies have gotten increasingly less black and white (I do not mean the colors), with multi-dimensional characters, heroes with a dark side or villains that seem relatable, and it seems that the Lego minifigures are following suit.

In any case, Lego might be over 80 years old, and the minifigures over 40, but no matter how old you are, you are never too old to play, build or tinker with Lego!

Adult Valerie admiring the Lego store window. (Photo by Lale)

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Sources:

(1) Bartneck, C., Obaid, M., & Zawieska, K. (2013). Agents with faces – What can we learn from LEGO Minfigures. Proceedings of the 1st International Conference on Human-Agent Interaction, Sapporo pp. III-2-1.

(2) xkcd

(3) http://b1creative.com/blog/the-history-of-the-lego-minifigure/


A matter of kilos

It’s been the topic of a weighted discussion for quite some time, but today it has been decided: “Le Grand K” will no longer be used to define a kilogram.

“Le Grand K” is not a big box of Special K, but a platinum-iridium cylinder stored by the International Bureau of Weights and Measures in an underground vault in Paris that has defined a kilogram of mass since 1889. There are a few official copies, and many more copies, so each country has their own kilogram to calibrate to.

Last Friday (November 16th) the kilogram has been redefined so it no longer depends on a material object. Because a material object can be scratched, chipped or destroyed. Or stolen. Or accidentally thrown into the bin. And it can degrade – in fact, “Le Grand K” weighs about  50 µg lighter than its six official copies. You don’t really want to gold – ahem, I mean platinum-iridium – standard for weight to change in weight, right?

So now the kilogram will be defined based on a universal, unchangeable constant. Much better, I think you would agree. The constant of choice here is the Plank’s constant, a number that converts the macroscopic wavelength of light to the energy of individual constants of light. Representatives from 58 countries universally agreed on this new definition, so from next year, the kilogram will be constant forever.

The ampere (electrical current), the kelvin (temperature) and the mole (amount of chemical substance) have also been redefined. That means that all seven units in the International System of Units (S.I.) will be defined by universal constants:

meter unit of length
  • Originally defined as a 10-millionth of the distance between the North Pole and the Equator along the meridian through Paris, later as the distance between two scratches on a bar of platinum-iridium metal
  • Since 1983 defined as the distance traveled by a light beam in vacuum in 1/299,792,458th of a second, with 299,792,458 m/s being the universally constant speed of light.
kilogram unit of mass
  • Initially defined in terms of one liter of water, but since as a small ~47 cm3 cylinder stored in a basement in Paris.
  • Now redefined in terms of the Plank constant h = 6.62607015×10−34 J*s (J = kg*m2*s−2)
second unit of time
  • Originally defined as 1/86,400th of a day
  • Since 1967 it has been defined as the time it takes an atom of cesium-133 to vibrate 9,192,631,770 times
ampere unit of electrical current
  • Originally defined as a tenth of the electromagnetic current flowing through a 1 cm arc of a circle with a 1 cm radius creating a field of one oersted in the center
  • Now redefined in terms of the fixed numerical value of the elementary charge e (1.6602176634×10−19 C with C = A*s and second defined as above)
kelvin unit of temperature
  • The centigrade scale was originally defined by assigning the freezing and boiling point of water as 0 °C and 100 °C respectively. Note: absolute zero is the lowest temperature (0K =  -273.16 °C)
  • Now redefined in terms of the Boltzmann constant k = 1.380649×10−23 J⋅K−1
mole unit to describe the amount of substance
  • Since 1967 defined as the amount of substance which has as many elementary particles as there are atoms in 0.012 kg of carbon-12.
  • Now one mole substance contains exactly 6.02214076 × 10^23 particles. This constant is known as Avogadro’s number*
candela unit to describe the intensity of light
  • Originally taken as the luminous intensity of a whale blubber candle in the late 19th century.
  • Since 1979 the light intensity of a monochromatic source that emits radiation with a frequency 5.4 x 1014 hertz and has a radiant intensity of 1/683 watt per steradian in a given direction **
So that was “this week in science.” I’ll leave y’all with a related joke:

kilogram

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Sources/Further reading:

The international system of units: en.wikipedia.org/wiki/International_System_of_Units

The new kilogram was in the news: www.nytimes.com/2018/11/16/science/kilogram-physics-measurement.html and www.theregister.co.uk/2018/11/17/amp_kelvin_kilogram/

Comic from xkcd.com

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* Avocado’s number, however, states that 6.02214076 × 10^23 guacas make up one guacamole. (I knooooow, I already made this joke).

** I have to be honest and say that I have no idea what this all means

Bubbles!

Let’s talk bubbles…

bubbles.gif
Calm down there, buddy.

Over the summer, I have tapped quite a few beers. Some of those beers were Guinness. The first few times I went through the Guinness-tapping-process (who am I kidding, all the times), I would marvel at the fact that the bubbles were going down.

So, Guinness is an easy but slightly time-consuming beer to tap. First, you need to fill the glass about 4/5ths and let the bubbles settle. When you get that nice black/white beer/foam divide, you top it off by pushing on the tap (which is a slower flow). So that all takes a while. But that means you can stare at these sinking bubbles for quite some time.

giphy-5.gif
Guinness bubbles going down down down.

But wait. Bubbles aren’t supposed to sink? Aren’t bubbles gaseous and therefore lighter than liquid? Hence, shouldn’t they rise as bubbles do in normal bubbly beverages? What’s going on?

From a uni class some time ago, I remembered that Guinness bubbles sink, so at least I wasn’t hallucinating. But why I forgot why exactly. (Com’on, the class was years ago and who remembers anything anyway. There’s the internet for that.)

Of course, there is science about this. I mean. Scientists are basically fueled by coffee and beer. And Guinness is sort of both.

It seems that there are a few factors that contribute to the sinking bubbles: the type of bubbles, the size of the bubbles, and the shape of a Guinness glass.

First of all, not all bubbles in Guinness sink, just the ones you can see. When the beer starts to settle, larger bubbles start to rise (as bubbles do). Because of the shape of the glass, you can’t really see this happening: the bubbles originate in the bottom of the glass, which is narrower than the top, and they form a central column of rising bubbles. This causes an upward liquid movement. As a result (because the liquid doesn’t magiacally fountain out of the glass), a downwards liquid flow occurs along the walls of the glass. If all the Guinness bubbles were large (> 50 µm), as it is with lighter beers, the buyancy would counteract the liquid flow (they’d be superlight and not care about what the liquid is doing) and rise. However, Guinness has teeny tiny bubbles (< 50 µm) that just get dragged along with the flow. And therefore, along the walls of the glass, they appear to be sinking.

Flow pathlines in a glass of Guinness. Image c/o Fluent Inc.
Psychadellic flow lines in a Guinness glass. (Image © Fluent Inc.)

So the second factor is the small bubbles. Guinness taps have fine holes that cause these small bubbles to form*. Moreover, Guinness bubbles are nitrogen and not carbon dioxide, which is more easily dissolvable in liquid. Most bubbly beverages, including lager beers and soft drinks, contain carbon dioxide to create the fizz. In these cases, gas bubbles appear from tiny defects in the glass surface and continue to grow as more carbon dioxide undissolves**. But nitrogen gas doesn’t dissolve in liquid as well as carbon dioxide, so the bubbles that do appear don’t grow in size. In other words, bubbles stay small enough to be dragged along with the downward liquid flow.

Finally, add the fact that Guinness is very dark, causing a high contrast with the light coloured bubbles, and you see these nice sinking bubbles.

Now, if you are in a place where the drinking time is acceptable (pm), go get yourself a Guinness. Otherwise, just stick to coffee.

ezgif.com-reverse.gif
Reverse yellow bubble fish looks even more insane.

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* In a can of Guinness can there is a small ball that, as far as I can tell, serves the same purpose. Edit: it’s confirmed that this small ball – also called a “widget” (thanks to my uncle Tim for this factoid) – indeed causes the slow release of nitrogen after the can is open.

** What, that’s not a word? What’s the opposite of dissolving then? *googles* Condensing? That doesn’t sound right?

Sources: Bubbles the fish is from Pixar and most of the info is from: https://plus.maths.org/content/probing-pint

And of course, there is more beer physics if that’s your thing (read it while drinking some beer responsibly): https://www.npr.org/sections/thesalt/2013/11/20/246390302/beer-tapping-physics-why-a-hit-to-a-bottle-makes-a-foam-volcano?t=1537774279547

I was at the Friggin’ Fringe

Almost three years ago, I mentioned – in a passing comment – the Edinburgh Fringe (“a ridiculously elaborate comedy festival that is held in Edinburgh every August, for almost a whole month”). Specifically, I talked about how much “Nerd Comedy” there was at the Fringe. This year was no different.

Well, I guess the difference was that, instead of going to the Fringe for a day or two, I was at the Fringe for a whole week. In fact, I was part of a show.

I still can barely believe it.

And of course, I was in a nerdy show.

Anyway, it was absolutely amazing. We had a total of 162 people come to our show over the course of 5 days, which was an absolute amazing turnout. We got a lot of laughs. We sometimes lost our track (or the chords) but that was just part of the charm. We made a lot of silly faces. Well, I did.

FacesFringe
Some of Valerie’s many faces (I actually look worried a lot of the time)

For me, it was mostly a lot of adrenaline. I know this barely constitutes as a proper blog post about doing a Fringe show, but I just wanted to have mentioned it. While I’m at it, let me thank Matt, Coren, and Yana for being such amazing co-stars; Valentina for the amazing organization; and MCAA for putting me on a stage.

There will be a video for those that unfortunately had to miss it, at some point in the pretty near future. So if you were like *damn, can’t believe I missed that,* there’s no need to worry!

FringeAngles
Some of Valerie’s many angles

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Note: wow, that is a lot of pictures of me, it’s quite unsetteling. I’m so sorry.

An ignobel cause

Disclaimer: if you’re a bit hungry and/or know that reading about spaghetti will make you hungry, I suggest you go eat some spaghetti before you continue reading… But if you do, keep at least a few strands uncooked, you might need it later on.

An odd article popped up on my go-to news site the other day. And then the day after that, an article on the same topic popped up in the newspaper I was reading. It was an article reporting on the science of breaking an uncooked spaghetti.

No, I’m not joking.

And apparently, the research solves a decade-old problem. I never knew spaghetti could pose a decade-old problem, except for maybe the secret spaghetti-sauce recipe of an Italian-American family but that’s a century-old problem, I would say.

So if you’d go into your kitchen now, take a strand of uncooked spaghetti, hold it at the ends, and start bending it until it snaps, you will see what this mystery is all about. Most probably, you have now ended up with three or more bits of spaghetti. If you are super bored or think snapping spaghetti is super-fun (this is what Richard Feynman apparently thought), you can try it again. And you will notice the spaghetti almost never snaps into two pieces. Or you can just take my word for it…

In 2005, some French physicists came up with a theoretical solution to why spaghetti never breaks into two, because this unsolved mystery Richard Feynman broke his head about merited some further research…

When a very thin bar (or strand of spaghetti) is being bent, this will cause the strand to break somewhere near the middle. This first break will cause a “snap-back” effect which essentially causes a vibration to travel through the rest of the strand, causing even more points of fracture, which results in three or more pieces. In other words, is very rare to end up with exactly two pieces of spaghetti.

These French researchers were rewarded with an Ig Nobel prize for their finding. An Ig Nobel prize is a prize that is rewarded “for achievements that first make people LAUGH then make them THINK” and also the reason for my best quiz achievement ever.*

crack-control-1
Experiments (above) and simulations (below) show how dry spaghetti can be broken into two or more fragments, by twisting and bending. (Image: MIT)

And now, years later, mathematicians from MIT have added to that research by coming up with a way to ensure a dry spaghetti strand does break exactly in two: by first twisting the spaghetti before bending it. The twisting part causes stresses in the spaghetti strand that counteract the snapback effect when it eventually breaks. When the spaghetti does break in to, the energy release from a “twist wave” (where the spaghetti pieces untwist themselves) ensures there is no extra stress that would cause more fracture points. So there we go: the spaghetti breaks in exactly two pieces as long as you twist it enough.

crack-control-2
Experiments (above) and simulations (below) show how dry spaghetti can be broken into two or more fragments, by twisting and bending. (Image: MIT)

Now, this theory isn’t only limited to breaking spaghetti. Understanding stress distributions and breaking cascade also have some practical applications, according to the authors: the same principles can be applied to other thin bar-like structures, such as multifibers, nanotubes, and microtubules.

Now, if you haven’t already, go get yourself some spaghetti.

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* The question: who has one both an Ig Nobel and a Nobel prize and for what?
The whole table looked very confused and I just said very confidently “André Geim, levitating a frog and graphene” so it turns out a degree in nanotech is super useful for winning quizzes. (Actually, I’m not even sure we won and I doubt it was thanks to me answering that one question correctly, but I’m pretty sure I will never live up to that moment ever again.)

EduTourism (II)

I had just submitted my PhD thesis for review (*mini-applause for myself*) and decided that the two months I had before my PhD viva (or PhD defence) would probably drive me half-insane and maybe I needed an extended break somewhere very far away.

So I went very far away: I booked a trip to Australia. However, still being me (as in: a science communication addict?) and considering my previous experience as an edutourist, I emailed a few universities to let them know I would be around and willing to volunteer at any scicomm event they might have. One university replied. I also signed up to an Australian mailing list and answered a call for volunteers.

So, in between my actual travels, I ended up doing some public outreach slash science communication down under. And boy, it was fun.

The university that replied to my spontaneous volunteering was LaTrobe University in Melbourne, where I had the opportunity to talk to a year 9 class (which are, I’m guessing, 14-year-olds?) about my research and my experience as a PhD student. I slightly changed a previous talk of mine (mostly left out the singing; oh yes, I went to a conference and brought my ukulele once, it was marvellous) and spoke to a class of maybe 30 students about the Physics of Cancer in general, and how my research sort of fits into that field. The students seemed very interested and asked some questions about what it’s like to do a PhD and if all that travelling isn’t very tiring. As thanks, I received a gift card which was super useful because I used it to buy a raincoat. Apparently, it does rain in Australia.

IMG_20180314_141116
La Trobe Institute for Molecular Science

The other event I attended was the Science and Engineering Challenge, which is a national competition organised by the University of Newcastle that challenges teams of high school students (I’m guessing 14-year-olds?) to do a range of different tasks related to engineering and science, such as building a water turbine, a suspension bridge, a catapult, creating an encrypted code or building an earthquake-proof structure. I helped out at the Sydney event for two days.

IMG_20180321_140237
Students at the final challenge: suspension bridge. It was very suspenseful.

Apart from the fact that I wasn’t allowed to take part myself – I would have loved to build a water turbine and catapult – it was absolutely amazing. My role was to facilitate the aforementioned activities (one for each day I was there), and it was really interesting to see the creativity and competitiveness of the students. Sometimes, the more unexpected design was more efficient, sometimes the group with the most extensive and thought-out plan ran out of time and couldn’t finish their idea. It was up to me to encourage the students to think both logically and out of the box without actually really helping (or so I tried).

As with many science outreach activities, the event relied on volunteers from universities. But more unusually, there were also volunteers from the Rotary and from companies (on Thursday I was there, a bank). This made for an interesting range of ages and backgrounds, which in my opinion was a wonderful extra touch and helped bring home the message that a) one of the most important skills for STEM* is creativity, b) with a STEM degree, you don’t necessarily have to stay in STEM, you can go into a whole range of careers, and c) STEM is really awesome, considering all these people – not all them working in or studying a STEM subject – that give up their time to come help at the event.

Anyway, I went on holiday for 5 weeks all on my lonesome and having a few days of scicomming in between was really fun.


Thank you Jess from LaTrobe University for the opportunity to speak to the y9 class and the tour of the university, and Terry from Newcastle University for signing me up for the Science and Engineering Challenge.

* Science, Technology, Engineering and Mathematics

Hug a micro-bear

Water bears. Moss piglets. Those are just two examples of “cutesy” names for tardigrades (literally “slow stepper”; because they look like they do everything in slow motion), some of the most amazing animals in existence (IMO). These little animals, averaging 0.5 mm when fully grown, are almost cute with their short, plump little bodies, eight legs and looking a bit like a tiny Michelin guy.

Ugh, I’m so fabulous! (scanning electron microscope image of  SEM image of Hypsibius dujardini)

Water bears are water-dwelling tiny animals that mostly live in mosses and lichens (top tip – get yourself a pet tardigrade by soaking some moss in water), but basically can be found anywhere (#GlobalCitizen).

And I mean everywhere. Some tardigrades live on the highest mountaintops. Others in the deepest trenches in the sea. They have been found in rainforests as well as in Antarctic regions. This is because tardigrades are so awesome. While they are not exactly extremophiles (organisms adapted to survive extreme conditions such as extreme temperature and pressure), they are able to survive extreme conditions for a certain length of time. Expose them for too long, and they will die, unfortunately. But expose them to extreme conditions, including very high or low temperatures, incredibly high or low pressure, air deprivation, dehydration or starvation for (depending on the system) a lot longer than what humans would survive, and they will bounce back! Some tardigrades have gone without water for more than 30 years, just to rehydrate and get back to living.

056a089504144ced64489af824b62b3b
Happy Space Tardigrade

I mean, tardigrades can survive space! Tardigrades have been exposed to open space and solar radiation combined for 10 days and have lived to tell the tale. This makes them the first known animal to survive in space.
Just to give you a few more examples of the extreme conditions tardigrades have survived in:
    • Tardigrades have survived extreme temperatures, such as a few minutes at 420 K (151 °C) or 1 K (-272 °C) at the other extreme. Put one in -20 °C and it could survive for 30 years.
    • As well as surviving the extremely low pressure of a vacuum, they can withstand very high pressures such as 1200 times the atmospheric pressure (or even 6000 times for some species).
    • The longest that living tardigrades have been shown to survive in a dry state is nearly 10 years.
    • Tardigrades can survive 1000 times more radiation than other animals.R8CozXH
Basically, they could survive global extinctions. In fact, they are one of the few groups that have survived Earth’s five mass extinctions.
So after the end of the world, whether human-inflicted or natural, we can at least count on these amazing little creatures to survive the apocalypse. Maybe they will even evolve to giant, sentient, space-travelling (no spaceship required) giant water-bears.
Actually, giant water bears would be terrifying. Let’s not think about that.
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Source:
Most (read: all) of this was found on wikipedia, the ultimate internet information hub that we all love to hate. I found the images at some point while browsing imgur, they’ve been on my phone waiting to be used for ages. I can’t find their original source.

Polymath (πολυμαθής)

Sometimes I feel like I was born in the wrong era.

Usually, this feeling is music-related. Now that I have renewed access to my dad’s old record collection (and a record player, #Hipster), I can’t help but feel that rock music from the ’70s and ’80s surpasses anything being made now. Comparing music from the “olden days” to music now is of course not entirely fair; what still remains has already withstood the test of time, current music hasn’t had to (yet).

Music aside, my wrong-time-feeling also applies to how I feel about science and research. Nowadays, scientific discoveries seem to always be the result of hard work of an entire team of scientists for countless years. There is so much knowledge and information out there, it seems imperative to find one’s own little niche and specialise, specialise, specialise. It is impossible to be a master of all.

However, I long for the golden old days of the polymaths and the homines universalis when academics were interested in all fields. They were allowed, or even required, to branch out, study all sciences, not to mention humanities, linguistics and arts. I’m speaking of people like Galileo Galilei and Leonardo Da Vinci. My favourite person, D’Arcy Thompson, would also be considered a polymath.

A polymath is defined as someone with “knowledge of various matters, drawn from all kinds of studies ranging freely through all the fields of the disciplines, as far as the human mind, with unwearied industry, is able to pursue them” (1). I noticed while perusing the wikipedeia page, that the examples given of Renaissance Men are indeed all men. Even if I was born in the right era to be an homo universalis, I would still have been born the wrong gender.

However, there are at least a few examples of female polymaths, and I wanted to introduce you to one of them: Dorothy Wrinch. Just in case you wanted a more nuanced example.

dorothy_maud_wrinch

Dorothy Maud Wrinch (12 September 1894 – 11 February 1976)

Dorothy Wrinch was a mathematician by training but also showed interest in physics, biochemistry and philosophy. She is someone who – even though I’ve only recently heard of her – is an excellent example of the homo universalis I wish I could be. She was also a friend of D’Arcy Thompson, though if I remember correctly, they mostly upheld a written correspondence.

In any case, Dorothy is known for her mathematical approaches to explaining biological structures, such as DNA and proteins. Most notably, she proposed a mathematical model for protein structure that – albeit later disproved – set the stage for biomathematical approaches to structural biology, and mathematical interpretations of X-ray crystallography.

She was a founding member of the Theoretical Biology Club, a group of scientists who believed that an interdisciplinary approach of philosophy, mathematics, physics, chemistry and biology, could lead to the understanding and investigation of living organisms.

She is described as “a brilliant and controversial figure who played a part in the beginnings of much of present research in molecular biology.  (…) I like to think of her as she was when I first knew her, gay, enthusiastic and adventurous, courageous in face of much misfortune and very kind.” (2)

Actually, come to think of it, maybe Dorothy was born in the wrong era. Nowadays, using mathematical approaches to protein structure is practically commonplace. Though I’m not quite sure how well philosophy would fit in.

Anyway, I still feel that interdisciplinary research, and having broad interests, is not the easiest path to go down. But as long as we have inspirational people to look up to, past and present, we know it is worth a try.

(Wow, went way overboard with the #Inspirational stuff towards the end there.)


(1) As defined by Wower, from Wikipedia.

(2) Dorothy Crowfoot Hodgkin (Wrinch’s obituary in 1976).

An updated version of this post was published on the Marie Curie Alumni Association blog on March 19, 2019.

Octopuses suck! (but not like that)

You might know the frustration of trying to get a suction cup to stick: cleaning the sucker and surface over and over again, pushing on the sucker for increasing amounts of time and with increasing amounts of force… But nothing helps, the basket of shower gels and shampoos, or whatever you’re trying to attach to a wall/window/door (or maybe you are trying to climb a tower) just slowly slides down – if you’re lucky – or falls to the ground – on your toes, if you’re not so lucky.

Well, there might be some hope. Researchers are looking to nature to find a solution to this everyday frustration – because I’m positive this was the incentive: minimising shower rage. There is a whole field based on nature-inspired solutions and products, mostly grouped under the name Biomimetics, because why would you try to reinvent the wheel if nature has evolved a useful means of transportation?

Back to the suckers. In June, I came across a News&Views article that made me do a double take. You see, I had a brief moment of surprise when I thought the Nature journal had taken a liking to hentai (if you don’t know what this is, please do not google it). But it was not what I thought; “How to suck like an octopus” dealt on materials science, and how to make rubber sheets that can stick to surfaces. In other words: how to make better suckers!

It turns out that octopuses use suction cups to attach to rocks and to grab things. And it turns out the special shape of their suckers enhances that adhesion. Boom, let’s try and create a material that does the same!

Inspired by Octopus vulgaris, researchers tried to recreate the ideal adhesive material that sticks well to surfaces but also is able to detach easily. Octopus vulgaris‘ trick is a dome-shaped bulge at the bottom of the suction cup (see figure). This “dome in a cup” structure – mimicked by micrometre-sized hole with a dome in it (see figure, again) – enhances adhesion to wet surfaces by providing capillary forces between the dome and the substrate. On dry surfaces, the presence of the domes does not increase adhesion but doesn’t cause any decreased adhesion either. The only difference between the octopus suckers is that octopuses have muscles in the suckers to flex, expand and contract them, increasing control of the adhesion and detachment. There are still some things to mimic then; it’s always nice to have something for the “Future Work” bit of a paper.

I think biomimetics is like super cool, though I have to admit that sometimes the applications seem unrealistic or too far-fetched; in this case, the authors suggest applications in manufacturing – transport of materials – and biomedical applications such as wound dressing. However, I still believe there is great value in biomimetic research: better understanding – the biomimetic device can teach us of the workings of the in natura equivalent (I know that’s not what in natura means) – and it’s just fun to do!

The News&Views author agrees:

“Applications aside, understanding and mimicking the fundamental science of attachment strategies used by sea creatures can just be plain fun.”

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Octupus vulgaris suckers contain dome-shaped bulges. Flexible biomimetic rubber sheets containing an array of micrometre-sized holes with a bulge in each hole.


References:
Original Letter: http://www.nature.com/nature/journal/v546/n7658/full/nature22382.html
Suction Cup Guy: https://www.youtube.com/watch?v=7XCk3AtUbvA