The 
food be. fin. of the young^Arelic terns is usually in the hunch peture 
bvit if they are very eager to get theffish they may aao t wh at i Cell 
the i*'.rect Foog begging posture with the neck stretched upwards but 
otherwise like the Hunohec food begging; A b,rd «* may adopt the 
erect food begging on first seeing its perent or mete but as the two 
come closer together the atxsc neck becomes mor e and more withdrawn 
until the hunche4 postur- e is assu- med, The erect t oi. the food 
begging seems to be assigned- to make the beggingv birds as conspicuous 
as pos ible, which it would often not be ifi thehunch posture where 
ther~- was vegetation* From the observe Lions We inrdeon A herring gulls 
a black headed which we res ret. fiom hatching.Jua we got the 
fmpres ion that there was the same sort of effect in the erect and 
hunch, phases in the begging oi these > ■ ^ that instead of 
e 1 shift f to m the erect phase to the hunch, 
th^ two phases alternate but the hunch becomes more ai.d more preaominent 
the cl-oser the chick gets to its •parent'', bertainly we got the 
impression, and X think that Uli and kita agree , the top phase often m 
makes the chick conspicuous in places where it would be hidden irom 
view if it atiKXKsfc be ;,ge d only in the hunch* Wh&t they don’ t cxltogether 
agree with yet, though they haven’t specially lookeo. , is that the 
top phase becomes less and less^wlie closer the parent coaxes to the 
chick. if we are right on this point it would seem probable that 
the erect base of the terns 1 s food oegging is ^mologp s ^ith 
of the gul s' • 1 have carei lly avoid ei or i ing 
into the argument beet use i understand s that? their 
rather different f om that of the chicks. .However 
it might perhaps be possible to incorporate this too. Ivd write 
somewhere in your thesis 1 think, that thebottom phase ox the female’s 
begging JacridantiEKl i.e. the bottom of tne *1bob r , is 
the hun&. Where does the top of the bob come from, 
alert posture or even a resting posture Y Ur coulu a 
_ a. 
the erect phase 
the adult gulls 
food begging is 
iuentical v 
Is it merely and 
part oi it have 
been developed specially zo make the female conspicuous. From what 
1 recall oi the black has dec film the female plague* tne m< lx enough 
by her presence without ht v ing to m< xe nex’sexi more cout;picuou.'. than 
she is. It may also be significant that the female isn’t having\to 
compete with other females to get the mt.lis xood as are the youn^ 
gulls and for that matter both youn t . ana adult ^mole terns. \ 
This interpretation ol^MfiS^Sp p^f so of food begging is supported 
by the kittiweke since in th^si species food begging is in the hunch 
end there is no long neck phase. Almost all feeding takes piece on , 
the nest in this sp so that there is no neea for the f emi: le or chick 
to make itself co nspicuous. 
absence oi' Bergman, Go ©the and 
Bsth 
r^s t? Iks were the 
in — ■. , 
only ones oJpo\xt gulls. Baerends hr d decided there was no poino in 
discuss in^fjouilding wh ich his people have been forking on in view 
of the fact that 11 i and Zah&vi, who had been working on it ©t Ravengless 
this summer were neither able to st£ y for thegull conference. Ana in 
any case the nest building is not really part oi Lh comperttiye stuaies 
wnich the corifei’ence concentrated on in the brief two days it lastea. 
