The Wheeling daily intelligencer. [volume] (Wheeling, W. Va.) 1865-1903, 1874-05-09
GlM9etsQli9llf,lIr,lrer:
THE EVOLUTION OF PLANTS
AND ANIMALS.

AMI ANIMhL5s
An Enumeration ofthc Causes which
Induce Species TO Develop into DIFF
feront Forms Of Life i4
tRiyhGh article, showing the effect Of eneiuIEs, o
climate, aid Of general conditions upon a
kinds Of OrganlSms
Editors Of the GuellIgeneGr; r.l
Since, at no time during the period o
this worlds duration has ito condition
ever remained constant; and since the 70
l4tonB existing between all organisms
and their organic and inorganic environ
ments have been continually changing, II
follows, that no race Of plants or animals
could remain immutable and survive II
the struggle for existence. II no indivld'
uals varied 30 as 10 present some Inn
proved adaptation to their slowly chang
ing surroundings, natural selection could
not operate,-through choice Of the At
test,-to gradually bring the species into
harmony with its environment, and thus
better suited organisms would tend &c
supplant Il, causing Ii In course Of time "a
become finally extinct. Observation
shows, however, that no such species ex-
lists. ThetmembeEa Of each species are
ever slightly'varying, but, 60 long 90 the
environment remains constant, natural
selection prevents the variations from ac-
cumulating on either aide OF the advan-
tageous mean, while, when an alteration
In thesurroundings occurs, all individuals
which manifest q setticeable variation
from the eatab lished mean will tend IL
survive In the struggle TOR existence, and
producing offspring which inherit the
variation, will modify the average chRrac.
ter Of the race. 70 h
ILLUSTRATIONS OF sERvIORABLR vARIA-
T1oEs.
mo two bears have Just tho same
amount of;hAir !. no two moths have Just
the same length Of proboscis; no two
antelopes are exactly matched In feet
ness. Now, II increasing cold renders q
thicker covering useful 10 the bear, or II
the frightening of Q flower. calyx, due. to
Sslght change in the soil or quantity Of
sunlight renders d longer proboscis use
tul 70 the moth, or il the Immigration q
carniyorous animal makes 1t necessary for
RntelOpes 10 run often for their lives, then
IN each generation the thickeat- coated
bears, the longest.tOngued moths, and the
teetest antelopes willsurviVe. Every in.
dividual variation In the direction Of a
heavier coat, a longer sucker, or a struc.
ture better adapted for fleeing with, gives
Its owner an advantage in the incessant
struggle for life, and these peculiarities
Will be inherited, while individuals which
do not vary or which vary In the wrong
direction will have to migrate or die" .
TIE DIFFERENT coLoRs AND THE GAuDY
HUEs OF PLANTS AND ANIMALS MAINLY
DUE TO NATURAL SELECTION.
According 10 the theory Of the survival
OF tho dttest, each species Of plants and
animals will be characterized by the
possession Of that color which is most ad.
Vantsgeous 10 the species In the struggle
for existence. Thus bears, rabbits, and
other fur bearing animals which are
varlously hued according to the nature Of
their station, are invariably found 10 be
white when inhabiting regions Of snow,
such as the frigid zones. Their compare.
tive indistinguishability from tho sur
rounding snow would afford them great
advantage over differently coiorcd COM
petitors, in securing prey and in conceal.
ment from enemies. Now, as Mr.. A. r
Wallace observes, "concealment ia useful
to many animals, and absolutely essential
10 some. Those which have numer-
GUS enemies from which they cannot es-
cape by rapidity Of motion, find safety
In conCCGlmCnt. Those which prev
upon Others must also be go consti.
tuted as not to alarm them by their
presence or their approach, or they would
soon die OF hunger. In striking harmony
with this general principle we, find that
the great majority oil animals arc so
colored as best to escape notice, and that
animals which arc not protectively COL
ored arc animals whose habits oil life arc
such as to enable them TO dispense with
secrecy. The polar bear Is white, as the
California bear is grey and the Hindos-
tan bear black, because with o coat thus
colOred II can best escape notice and Sc
cureits prey. The polar hare has per.
mancnt coat of white, but the ALPINE
hare tho Arctic fox, and tho efmino,
which do not live among perpetual snow,
have coats which are white in the winter
only. Arctic owls; falcons, and bunt.
ings arc colorCd snowy white; and the
ptsrmigan is white In winter, while It's
summer plumnage so exactly harmoniaes
whit the lichen covered stones among
which 1t delights to alt, that person may
walk through REflOck Of them without
seeing single bird. In the sandy des-
erts Of Northern Africa, oil birds, with
out exception, all snakes and lizards, and
all the smaller mammals, are of q uni.
form sandy COLOR, Tic camel Is tinted
like the desert in which he lives, and the
Same is true Of the antelope and the
Australian kangaroo. The tawny lion
is7slypical example Of this, and must be
almost invisible when ctouched upon the
sand or among desert rocks and stones.
His brother tho tiger, is Jungle animal,
and hides himself among, TUFTS Of grass or
Of bemboos, and in these positions the
vertical stripes with which his body Is
adoraed, must so assimilate with the yer.
tlcal stems of the bamboo as, to assist
greatly in concealing him from
his approaching prey. How re-
markable tits that besides the lion and
tiger, almost all the other large cats are
arbOresl in their habits and almost, all
have ocellated or spotted skins, which
must certainly tend to blend them with
the background OF foliage; while the one
exception, the puma, has an ashy brown
ulilorm fur, and has the habit oil olinglnG
80 closely5to the limb soi a tree, while
waiting Tor his prey opsss beneath, as TO
be hardly dbtinguishable from the bark.
Such nocturnal animals as owls, goat
suckers, mice, bats, and moles are dusky
colored. In tropical forests, where the
trees arc laden with green foliage all the
year round, we find brilliant green pigeons
and parrots; while the northern snipe re-
sembles the msrshy vegetation in which
itllves, and the wood coCk5 with itsyarle.
gated browns and yeltows, Is inconspicu-
GUS among the autumn leaves. Arborcal
: y. T..