BBC Focus - 03.2020

Q&A

GET T Y

IMAGES

X3,

NIGEL

SWALES

ILLUSTRATIONS: DAN BRIGHT

JIMMYPHILLIPS,BRISTOL

WHAT’STHETALLEST MOUNTAIN IN

THE SOLAR SYSTEM?

YOUCANCUREYOUR

HICCUPSBYDRINKING

FROMTHEWRONG

SIDE OF A GLASS

OLDWIVES’

TALES...

Hiccupsareinvoluntarycontractionsof
thediaphragm.Thesecontractionscause
a suddeninrushofair,slammingshutthe
leaf-shapedflapofcartilageinyourthroat
knownasthe‘epiglottis’(thisis what
causesthe‘hic’sound).
Thedocumentedcuresforhiccups
generallyfallintothreecategories–
raisingthelevelofCO 2 inyour
bloodstream(holdingyourbreath),
stimulatingthevagusnerve(sticking your
fingerinyourear– oranus!),and
distraction(asuddenfright).The
techniqueofdrinkingfromthewrongside
oftheglassmaybea combinationofthe
lasttwo:it requiresyoutoconcentrateon
thetask,andcolddrinksstimulatethe
vagusnervethroughthestomachwall.If
youdrinka largeglasswithoutstopping,
youmayeveninterruptyourbreathing
forlongenoughtoaffectyourbloodCO 2
levelstoo.
However,noneofthefolkcuresfor
hiccupshavegoodscientificresearchto
backthemup,andscientistsdon’t
understandthemechanismsthatmight
beatwork.Moststudiesareanecdotal
reportsofcuresforpatientswith
persistentboutsof‘intractablehiccups’
thathavegoneonformonthsoreven
years,andit’spossiblethatthesehavea
differentunderlyingcause.Formore
ordinaryepisodesofhiccups,thereseems
tobea largeplaceboeffectatwork– soas
longasyoubelieveinthe cure, it will
probablywork.LV

Leavingasidetheobviousanswerthathumans

oftendeliberatelyintroducefishtolakesand

ponds,wecandrawa comparisonwiththe

populationofisolatedislands.Justasanisland

mayoncehavebeenconnectedbya land

bridge,solakesmayoriginallyhavebeenpart

ofriversystemsthatdriedup.Ora rivermay

have flooded long ago and briefly flowed into

low-lyinglandtocreatea populatedlake.

Somelakeresidentsareevendescendedfrom

ancestorsthatcrossedfromonelaketo

another.Whilemostfishcan’ttravelveryfar

overtheland,theireggswillsurviveforseveral

hoursoutofwater.Whenwaterbirdscometo

lakestofeed,fisheggsmightgetstucktotheir

feathers, hitching a ride to a new home.LV

OlympusMons,anextinctvolcanoonMars,is

oftenquotedasthehighestmountaininthe

SolarSystem,ata heightof21.9km(twoanda

halftimestheheightofEverest).However,the

mountain peak in the centre of the Rheasilvia

craterontheasteroidVesta,atabout22.5km,

appearstobemarginallytaller.Wedon’t

knowforsurebecauseofdifficultiesin

definingthemountains’‘base’heights,and

uncertainties in measurements.AGu

AMY-GRACEENZER

HOWDOFISHENDUPIN ISOLATED BODIES OF

WATER LIKE LAKES?

OlympusMons,

illustratedhere,is

an extinctvolcano

on Mars