MICHELLEHAYWOOD
Weird Science , a farewell
In her final piece for SCUBA , Michelle Haywood takes a look back at some of the gems she unearthed over a decade of columns
A
decade ago , BSAC decided to have its own in-house publication , and SCUBA was born . I ’ m not quite sure of the reasons why , but I was invited by the editor , Simon , to contribute a monthly column [ all explained in this issue ’ s Editor ’ s Letter ]. Initially , I wrote about the people I met and my experience running a dive charter operation . After a few years of that , Simon suggested a shift to writing something more scientific , playing on my background of being a research scientist . I ’ ll freely admit that , at first , I was reluctant . Any scientist knows that there are lots of other scientists who know more about any subject and I didn ’ t want to step on anyone ’ s toes .
I gradually realised that instead this was a brilliant opportunity to ask and answer those niggling ‘ I wonder why …?’ questions . I have a list on my phone of ‘ column ideas ’ and as I ’ m interacting with divers and teaching diving , I jot down the ‘ why ’ questions and every month pick one question to answer . The result of which is that I now know an increasing number of bizarre facts that are almost totally useless for your average pub quiz ! Looking back over the last few years , I ’ d like to share some of those facts . You too can have your memory banks filled up by diving science trivia .
Who knew that jellyfish are the most efficient swimmers of all time ? They aren ’ t fast but by taking advantage of changing the pressure inside their bell , they manage to make the most progress for the least amount of energy . Sharks have a highly conductive jelly in little pits around their snout , which allows them to sense the earth ’ s
‘ I ’ ve had a blast researching and writing these columns ’ magnetic field and navigate incredibly long distances . Octopus and cuttlefish change colour by stretching small balloons of coloured dye underneath their skin , and there are layers of different coloured balloons that can be synchronised to give rippling patterns . Comb jellies generate rainbow pulses of light due to refraction in their hair-like cilia and release eggs and sperm continuously through their mouths . The narwhal ’ s tusk is an overgrown canine tooth that can detect temperature , water pressure and salinity .
Periwinkles create a slime trail using a molecule similar to human snot which uses up to 60 % of their energy , so they will follow another trail if possible . This slime behaves oddly , so as the snail puts pressure on it , it becomes increasingly free-flowing . Limpets use the same kind of slime trail to return to their home scar where the rock is etched so that their shell is a perfect fit . Many traditional suncreams contain chemicals that stop coral larvae from moving and forming a hard skeleton and thus contribute to damaging our coral reefs . A group of chemicals called PCBs accumulate in the fat stores within marine animals and can cause neurological defects as well as impair breeding in orcas .
Lobsters turn red when cooked because heat destroys a protein called crustacyanin , so that it can ’ t mask the colour of the red Astaxanthin . That ’ s the same colour molecule we see in cooked prawns and in flamingo feathers . Sea hares use chemicals from red algae to make their purple dye which irritates by blocking their antennules , and so sea-hares can escape being eaten . Puffer fish and blue-ringed octopus contain bacteria that produce a toxin called TTX which is remarkably poisonous and stops your nerves from maintaining your body .
Sleep deprivation caused by getting up stupidly early for a dive had similar dangers to getting everyone drunk by impairing performance , which is not what you need on the drive home after a day ’ s diving . Farting in a drysuit may help you stay warmer if you produce lots of methane , but the volumes aren ’ t usually high enough to flush out the air . Humans are so closely related to seals that we still have the same arrangement of bones in our arms as they do in their forelimbs . Repeated exposure to cold water can cause the bones in your ear to grow larger and reduce the size of your ear canal .
And there you have it . A little trip through the headlines of years of strange science related to diving columns . I ’ ve had a blast researching and writing these columns , but I ’ m off to new adventures . If anyone is interested , I still have a few questions left on my list that I ’ d like to know the answers to . I hope you never stop being in awe of the wonders of the marine world and wish you all safe diving . �
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