Evening star. [volume] (Washington, D.C.) 1854-1972, 1929-01-27
CONTINUED From Third Page.)

creatures live suspended, swimming or
drifting more or less inertly in the
water.
What is the result of this? The re-
suit Is that the waters of the sea almost
everywhere TEEN with living things,
some large, but many very small. Thus,
whereas on land all creatures must be
able to get about in order to secure
SUFFICIENT food, the creatures in the sea
are able to get food in three, different
ways.
Many sea creatures are capable of
rapid locomotion, as the whales, most
kinds OF fish and crabs. But locomo-
ton is not really necessary for creatures
living in water teeming with smaller
living things There are two additional
ways for them-or some of them at
least--to secure sufficient food.
Very many animals of the sea fasten
themselves securely to the bottom, as
do the oysters and the corals and a
host of other types with strange and
unfamiliar names, and let the water do
the. work of bringing food to them.
Others, like certain jelly fishes, simply
float about, surrounded by their food
supply.
It is commonly remarked that life
came from the sea and that In the
sea are TO be found those primitive ami
Ald1 GypGS 4kOuI Wtl1CLl A0k1u dAIO
the active animals of the sea arose.
There seems to be no logic in this sup
position.
Distribution of Life.
About three-fourths of all the known
kinds of animals live on the land, but
this formidable array is distributed
among only few of the major types.
Less than one-fourth of all the differ
ent kinds of animals that SO far have
been described live in the sea, but these
sea animals are distributed among
about three times as many major types
as are the ANIMALS inhabiting the land.
Thus of the major types of animals,
nearly half again as many as all land
living types together, are exclusively
marine. These include such creatures
as the starf1shes, the Sea-urchinS and
various others unfamiliar to any but
biologists.
Three times as many different kinds
OF animals are found on land as are
found living in the sea. But in the sea
there are three times as many major
types of animals as are found on land
The occurrence in the sea of so very
many different types of animals having
a structure showing wide departure
from the structure of those creatures
with which we are most familiar, natu-
rally has, given, rise to the idea that in
the sea we find the reservoir of prim-
tive types of life from which all other
types arose.
But this phenomenon is capable of
another and much more logical explana-
ton. Land animals can secure their
food In only a single way-by going
after it. Sea animals secure their food
in three quite different ways. Three
times as many ways of securing food
means three times as many possibilities
of variation In the bodily form and
structure of the animals concerned.
Thus the excess of major animal types
found in the sea is simply In agreement
with the increased possibilities of secur-
ing food and implies no evolutionary
inferiority of sea animals as compared
with animals on land.
What can we learn in regard to the
major groups of animals from the fossil
record? The earliest aquatic fauna that
we know, that of the Cambrian rocks,
was in its broader aspects Singularly
similar to the aquatic fauna of the
present day. Every one of the numer-
Gus component species falls at once
within definite phylum as outlined by
the living forms, and in a definite class
within that phylum. Many of the diff
ferent kinds Of animals can be recog-
nized as members of families still exist
ing, while few may be assigned even
to. recent genera.
Life Status Unchanged.
The long list of animal types repre-
scented by the fossils in the Cambrian
and Immediately succeeding rocks and
their general agreement with the ami
mails of the present day can have only
one meaning. 1t shows conclusively
that as far back as Cambrian time the
status of the animal world was, in its
OF course it iS.quite likely, indeed it
Is most probable, that animals existed
long before the commencement of the
FOSSIL record. But in this case, Judging
from the correspondence between the
animals of the Cambrian and those of
the present day. we may safely predicate
similar correspondence between the
animals Of the Cambrian and those of
more distant past
Within each major group of animals
we see In the fossil record a very diff
ferent picture. There Is a constant
change from one horizon to another.
These successive variations are prob
ably simply indications of a direct re-
Spouse to physical alterations in en-
vlronment favoring now one type or
subtype, now another
This continuous alteration in the ele-
ments within restricted groups is per-
since THESE are the most familiar of all
animals.
Inc progressive changes in the reptiles
from the CarboniferouS to the end of
the CretaceouS and of the mammals
from the top of the basal Eocene to the
present day. or rather to the period
JUST past, the Pleistocene, forms a story
OF most absorbing interest. Here we
can trace the gradual DEVELOPMENT from
comparatively insignificant BEGINNING tn
wonderful Towering of specialization
and perfection.
But 1t Is well to emphasize the fact
that every developmentaI line has GER
tam gaps. Some have these gaps large
and broad, while in others, as for in
stance IN the horses, the gaps are rela-
Lively small. But they are always there
dney are, therefore, natural, and not
que TO deficiency in the record.
Apes and Man.
=. AS an illustration of such a gap from
the latter fossil record there NAV he
mentioned the difference between the
man-hKe apes and man. No one can
DENY that the great apes are in their
general form very much like man. Yet
there is no fossil evidence whatever
that the most ancient man was mot a
man. The very early men were quite
ou1erent from the men We see today.
But all the earliest skeletal remains
have been determined by the most
competent authorities as definitely
eitner man or ape, and in no case
intermediate.
Other gaps are found between the
monkeys and the tenure, between the
cats and dogs and bears, and between
the bats and other mammals Az W.
contemplate the animals without hack
bones as snails. insects, jelly fish AND
earth worms, we notice that the gaps
betWeen the different prn,,nc tneoxas