Oxford Democrat. [volume] (Paris, Me.) 1833-1933, 1897-11-30
Why oaoops DIFFER I'M SIZE.

WHY UHOOOS DIFFER IN SIZE.
None Of the sea-blrds d In the habit
Of laying more than one egg, ~ oil
breed on such remote and Inaccessible
rocks, often In holes, that harm can rare
~ happen to their young, and therefore
very high percentage comes 70 matuf-
ity. Many Of those breed 10 companies,
and are 20 unAcquainted with danger
that they make no attempt to hide their
eggs or 20 leave the nest when the place
70 visited by some wandering naturalist
or egging party.
The habit Of the king penguin deserves
Z note for itself. This big antarctic bird
guards lts one white egg from harm BY
carrying Il, somewhat as marsuplAl
does its young, 10 . pouch formed by q
fold oil the akin OF the belly between the
thighs. Both sexes are provided with
this continuance during the breeding
season, and relieve each other Of the
burden Ut Intervals.
The gull tribe, however, are far more
exposed to accident and enemies, both
In adult life and - TO their eggs and
young, than are the penguins, petrels,
etc., mentioned above; aud here the rule
II from two (skuas) to four (gulls and
terns) eggs In nest. When we come to
the shore and marsh birds-the plovers,
snipes, sandpipers, jacanas, all OF which
nestle on the ground, usually near the
shore Of the sea or lakes-we judge them
to be exposed to about the average OF
dangers, since their nest complement Il
from four TO six; but their large tropical
b. e.uA htfsarna sartovn
and trumpet.r-birds. which reside in
trees or bushes, and can well defend
themselves, need lay only one or at most
two eggs n season 10 msintsin their full
census.
An odd feature In the notification OF
some Of the rctic-breeding owls, where
the nesting must take place at an unsea-
souably early and cold date In order Ia
give the Aedglings time to reach mature
strength before the succeeding winter
assails them, Is that these birds deposit
their eggs at intervals OF a week or ten
days. Ia this way the mother can en-
vclop 10 her plumage and keep thor
oughly warm one egg and callow
flsdgling at a time, and IA assisted, In
respect to the later eggs and iledglinxs,
by the warmth OF the Older young In the
nest.
have gone Into this matter somewhat
at length, though by no means exhaust
lively, because am not aware that the
matter has ever been exploited, and be-
cause 1t embodies general Law or prin-
ciple thst the nest complement Of eggs q
any bird is in eraa proportion 10 the
acreage danger 90 ,rhieh that species Is err
posed. believe that this ffctor Is fairly
constant for species or tribes OF similar
habits, and that exceptions indicate
peculiarities OF circumstances, which Ia
many cases We can easily perceive, be-
cause l believe that nature IL strictly
economical Of energy, allowing no more
eggs to be- laid, and consequently young
TO he produced, than the conditions jus
tify In each case. Thus the uniformity
OF svine population--the balance OF bird
life-is maintained.
Another derlvivate generalization IL,
that although BY ingenuity Ia ncst-build.
Ing or other requirement an individual OF
species may seem to benefit itself, this
benefit does not accrue To the total en-
hsncement OF that species or race (in r.
spec, To numbers, at least, because rs
ture countcracts the Effort towards nu-
mericsl Improvement by reducing pro-
portionateiy the fecundity or repro
ductive ability In that group.-from "a
Birds Egg" by Ernest ingersoll In Har-
per's Magazine.