W
ithfewerpeopleoutandaboutthis
spring,ourbirdsfounda quieter,
cleanerenvironment.Speciesthatsing
louderbesidebusyroads,suchasgreat
titsandsongthrushes,couldsingmore
quietly.Ground-nestingbirdswon’thave
beenflushedbywalkersanddogsasoften,
sotheireggswillhavebeenlessat risk.
Thewinnersarelikelyto includeskylarks,
lapwingsandcurlewsonfarmland,and
beach-nestingspecies,suchaslittleterns,
oystercatchersandringedplovers.Some
rarebirds– raptorsespecially– willhave
beenmorevulnerableto illegalpersecution,
dueto lackofprotectionbyconservation
staff,butlikewisewillhavebeenhelpedby
fewerpeoplewanderingneartheirnests.
Inthelongterm,gardenbirdswillbenefit
fromtheboostto monitoring– theBTO’s
GardenBirdWatchsurveyenjoyingrecord
participationduringlockdown.EdDrewitt
Whichbirdsgained
mostfromBritain’s
lockdown?
Wouldanyanimalssurvive
anuclearexplosion?
ORNITHOLOGY
SURVIVAL LEPIDOPTERA
MARINEBIOLOGY Whythelongface?
Allthebetterfor
eatingwith.
Littleterns
enjoyquiet
beaches.
A
t theblast’sepicentre,the
vaporisingheatis likethe
centreofthesun,soit’ssafe
tosaynolifecouldwithstand
that.Furtherout,organisms
abletohideincracksand
creviceswouldnaturallybemore
protected,butthereis thenthe
penetratingpowerofradiation
todealwith.Theanimalsbest
abletohandlethisapocalypse
wouldbetinytardigrades,or
waterbears,whichareabout
1mminsize.EuropeanSpace
Agencyexperimentshaveshown
thatthesemicro-organisms
canwithstandthevacuumand
radiationofspace,andwealso
knowtheycanpracticallyrise
fromthedeadafteryearsof
desiccation.Allusefulattributes
forsurvivinga nuclearbomb.
Intermsofradiationresistance,
tardigradescomfortablybeat
thefabledcockroaches.Their
lethaldoseis 5,000grays
(theunitbywhichradiation
impactis measured),
comparedto480–680in
Germancockroachesand
a mere4–10inhumans.
EllenHusain
Whydo
seahorseslook
liketinyhorses?
R
esemblingminiaturegee-gees
makesperfectsense.Seahorses
hideamongbladesofseagrass,or
camouflagethemselvesona coral
colony,thenwaitfortheirprey–
oftenminutecrustaceanscalled
copepods.It turnsoutthathaving
a narrow,elongatedsnoutandbig
cheeksis theidealcombination
forlifeasstealthyambush
predators.Theshapeofthehead
is hydrodynamic,soit slips
throughthewater,producing
almostnoripplesthatwould
alerta copepodtothedanger
it’sin.Oncewithinstrikingrange,
a seahorseflicksitssnoutupwards,
releasingelasticenergystoredat
thebackofitshead,likea catapult.
Inundera millisecond,it sucksin
thehaplesscrustacean,puffingout
thosebig,equinecheeks.Employing
thistechnique,knownaspivot
feeding,seahorsesaretremendously
successfulhunters,witha 90per
centhitrate.HelenScales
Tardigradesseem
tobevirtually
indestructible.
Whyaresome
moths ightless?
F
lightoffersmanyadvantages,butis
hardwork.Thisis whysomebirds
andmanyinsectshavegivenit up.At
least 25 familiesofmothshaveeithersmall
wingsornoneat all.Oftenonlythefemale
mothsbecomeflightless,leadingto strikingvis al
differencesbetweenthesexes.Intemperateclime
flightlessmothsflyinwinter,sotheirflightlosscou
beanadaptationto lowtemperaturesandstrong
winds,bothofwhichmakeflyingmorechallenging.T
femalesreleasechemicalpheromonesto attractmales
andinsteadofmaintainingflightmusclescandevot
moreenergyto reproduction.Butwhybeactivein
winterat all?It couldbebecausefewerpredators
arearound.However,therearealwaysexception
Oneis thevapourermoth– theorange-brown
malesfliterraticallyaroundBritishtreetops
fromJulyto September,whilethecurious,
near-winglessfemalesstayonthetrees.
LaurieJackson
Va
female(
male(above).
Q&A
July 2020