BBC Focus 02.2020

QESTION OF THE MONTH

EMAIL YOUR [email protected] TWEET US@SCIENCEFOCUSQA

Q&A

WINNER

Lukaswinsa bundleofstunningbooks

byRachelIgnotofsky,worth£51.96.

Thebooksinclude:WomenInScience,

WomenInSports,WomenInArtandThe

WondrousWorkingsOfPlanetEarth.

Featuringbeautifulillustrations

andstacksoffascinatingstoriesand

facts,thesebooksareanabsolute

treattoread.

hacheechildrens.co.uk

LUKASHINDMARCH,NORTHSTAFFORDSHIRE

DO FISH EVER GET

BORED IN FISH TANKS?

Weknowthatthenatureofa fish’stankwillhave

anin￿uenceonitsbrainandbehaviour.When

youngtroutarerearedina boring,featureless

tanktheydevelopa smallercerebellum(partof

thebrainthatregulatesmovement)thantrout

thataregivenrocksandplantstoexplore.Cod

rearedinsimilarlyenrichedtanksbecome be￿er

atlearninghowtocatchprey,andalso

recoverquickerfromstressa￿era

simulatedpredatora￿ack.

Butwhetherfishactuallyfeel

boredina waywecanrelateto

is hardertoworkout.

Fish-keeperssometimessee

theirpets‘glasssurfing’

• swimmingrepeatedlyupand
  downtheglassofthetank.This
  couldbetheaquaticequivalentofthe
  pacingofa captivetigerthat’sbored
  froma lackofstimulation.Butthe
  fishcouldalsobestressedfroman
  overcrowded or unfamiliar tank.HS

If weaddupallthelightcomingfromgalaxies(andthestars
withinthem),andfromallthecloudsofgasanddustinthe
Universe,we’dendupwitha colourveryclosetowhite,but
actuallya lilebit‘beige’.Averagedoverthewholesky,
however,thisbeigecolouris dilutedandappearsalmost,
butnotquite,black.GiventheimmensesizeoftheUniverse,
andtheabundanceofstars,it mightbesurprisingthatthe
skyisn’tbrightwhite.Thisis becausetheUniversehasa
finiteage,andthelightfrom the furthest stars hasn’t had
time to reach us yet.AGu

JASONWEBB,TENNESSEE

WHAT COLOUR IS SPACE?

COLINROWLEY,VIAEMAIL

ARE RAZORS WITH

MORE BLADES

REALLY BETTER?

Witha multi-bladedrazor,theleadingbladelis the

hairslightlyasit cutsit.Beforethehairhasa chanceto

retract,thenextbladereachesit andcutsa lile lower

down.Thisresultsina shavethatis notjustushwith

thelevelofyourskin,butactuallyslightlybelowit.

Naturallythisis subjecttothelawofdiminishing

returns,buta razorwithmorebladesalso

distributesthepressureofthebladecartridgemore

evenly.Thereis someevidencethatthiskeepsyour

skinaersothatyougeta moreevenshaveand

lesschanceofnicksandcuts.Soit is worthgoing

fora multi-bladedrazor,butwhetheryou’re

beerowiththree,five,orevensevenblades is

goingtocomedowntowhatfeelsmost

comfortableforyou.Almostallscientific

researchinshavingtechnologyis sponsoredby

oneoftherazormanufacturers,soa truly

objectivefigurefortheoptimum number of

blades is hard to comeby.LV