Birds do it, bees do it, even West Ham supporters do it

 

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Starling murmuration – an example of metachronal wave (Image by , via wikimedia Commons, CC-BY)

The world’s most renowned TV naturalist, Sir David Attenborough,  stands in a tropical forest. It’s dark. Suddenly a pinpoint of green light flashes underneath him, in the grass. Another flash, and another until they become too numerous to count. And then a pattern emerges – instead of random light flashes, which would create a steady background, like individual drops of rain create steady rain noise, the flashing fireflies synchronise. They create a rhythm, not unlike flashing traffic lights – or a lighthouse.

The synchronising of rhythms of individual insects is not limited to the fireflies. Perhaps less surprisingly, bees, the notorious collective, do it. Not the torch-like flashing but they shimmer in response to hornet approach.  So do starlings and fish that create mesmerising collective movements.

This type of movement is called metachronal rhythm or metachronal wave.  It’s produced by the sequential action (as opposed to synchronized) of structures such as cilia, segments of worms or legs. These movements produce the appearance of a travelling wave.

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A Mexican wave in Brazil. (Image by Danilo Borges via Wikimedia Commons, CC-BY 3.0)

It’s made by reacting and repeating the movement of your neighbours be it cilia  in a single cell organism or a human.  West Ham football supporters (and all the rest of them) succumb to a metachronal rhythm during a Mexican wave.

Literature:

Restless Creatures: The Story of Life in Ten Movements by Matt Wilkinson, 
  • ASIN: B01B39IRJ2
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18th century Art on Science: Joseph Wright’s “An Experiment on a Bird in an Airpump”

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“An Experiment on a Bird in an Airpump” (1768). Joseph Wright. 

Unlike his self-explanatory “Alchemist discovering phosphorus,” another painting of Joseph Wright of Derby, “An Experiment on a Bird in an Airpump” (right) is an enigma for a 21st-century viewer. Who are people surrounding the table? Why is the parrot in a glass bowl?

What is an air pump?

I don’t think I need to convince you that air has pressure and you can remove air from a vessel leaving a vacuum – or more likely thin gas – inside. But for people in pre-scientific time air was something indivisible like other elements – fire, earth, and water.

The air pump, which can suck the air out of a vessel, was invented by Otto von Guericke in 1650. One of the lucky first possessors of the air pump was “the first modern chemist” Robert Boyle. You may remember him from Boyle’s Law. Boyle conducted experiments with the pump and published a book about it in 1660. One of the experiments describes air removal effect on a bird:

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6+ animals that defy laws of nature

 

1. Walking fish

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Shuttles hopfish and its son (Image by Alpsdake/Wikimedia Commons)

Remember that  Guinness ad where the evolution goes back: men devolve into cavemen, birds into dinosaurs? It ends with two little fish walking to water and expressing disgust at its taste. These fish do exist. The fish from the advert is close to mudskipper – an Australian fish.

2. Living on land fish

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20th Century Art on Science: Gustav Klimt on Philosophy, Medicine and Jurisprudence

 

the_kiss_-_gustav_klimt_-_google_cultural_instituteThe Kiss (on the right) is one of the most frequent pictures in student dorm rooms. Female students that is. The gold, the flowers, gently undulating figure of a red-haired and pink woman being embraced and kissed by an angular and darker man what’s not to like?

But the early 20th century Austrian painter Gustav Klimt wasn’t always a crowdpleaser. In 1899 he was commissioned three paintings for the ceiling of the University of Vienna’s Great Hall. But Philosophy, Medicine and Jurisprudence caused an uproar of university establishment and were never displayed. They were later looted by Nazis and destroyed by the fire in 1945, so we have only a fragment in colour and black-and-white reproductions of the rest.

But even from the ghost of the paintings we can see that Klimt combined his strands of his cash-cow ornate female portraits with his post-Great Hall allegorical groups, as in “award-winning” Death and Life. (If you ever in Vienna, do visit Leopold Museum for Klimt’s works if nothing else. Death and Life is mesmerizing, it’s 2m x 2m but feels like five times that.)

Why were his Great Hall paintings called ‘pornography’ and ‘perverted excess”? Not because the educated people at the end of the 19th century didn’t see nude figures on paintings. On the contrary, classical paintings of this period were full of nudes – relaxing in languorous poses, plump and pink. Klimt’s nudes are emasculated, twisted – and have visible pubic hair and genitals, hence  pornography accusation. They also don’t suffer heroically as the heroes of classical paintings do, but in despair, viscerally – “in excess”.

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Somewhere Towards the End by Diana Athill

Reading this book is like having a conversation with an intelligent, wise*, interesting, very open person. A conversation, because some of the things the author says resonate despite our differences in age, upbringing, and nationality. For example, she describes how while falling asleep she imagines herself drifting on a raft at a dark sea. For me, it is a canoe and a large, Amazon-like river at night.

But the book of an octogenarian author, who became famous in her seventies about life and death is better than a conversation because a dialogue is fleeting like a rainbow, but the book remains – to be shared. The prose is beautiful as well as befits to a long time editor.

I wish my local library had more books  by  Diana  Athill.

3 Top Electrical Goods Useful in the Lab

An electrical coffee grinder (designed specifi...

An electrical coffee grinder (designed specifically for coffee beans, but the owner uses it for chopping twigs/teatwigs and tealeaves for making teas/infusions (Photo: Wikipedia)

Following  a resounding success of the article about  10 everyday things useful in  the lab, I compiled a hit parade of household electrical equipment useful  in the lab:

3) Coffee grinder – to grind large amounts of frozen cells. Just keep topping up with liquid nitrogen, it is surprisingly effective.

2) Hair drier – to assist with defrosting the glaciers in the lab freezer. Although I prefer plastic boxes with tap hot water: they don’t use electricity and working electrical equipment near water is always a bad idea.

1) Microwave is that piece of technology, which is indistinguishable from magic: an empty box that heats and boils whatever you put in it and even starts fireworks, if you place a piece of foil into it (I hope we are all adults here, please don’t do it).

In the lab you can use a microwave to:

* quickly heat up a small amount of water/TE/elution buffer to improve elution yields from spin columns;

*reduce antigen masking as part of immunohistochemistry protocol by microwaving slides for 5 minutes;

* melt agarose for gels for separating DNA and even proteins;

* melt autoclaved and solidified agar-containing media to pour plates for microorganisms;

* quickly heat up a buffer containing precipitated due to low temperature SDS or salts;

* emergency pastuerize of microorganism growth medium, when you decide to transform E.coli at  7 p.m. and there is no plates or autoclaved media and your lab autoclave has a notice “do not use” for the last 4 weeks.

Do you think my hit-parade missed something or know more microwave uses? Please, comment.