The sun. [volume] (New York [N.Y.]) 1833-1916, 1903-05-17
LINKS MAN AND The FISHES.
PROF. ROEIoSCHE TELLS or A
GREAT STEP ~ EVOLUTION.
HOs the GIN Brcather Became q Lung
Breather and Crawled Out on Land.
the First Real Ancestor OF Man--LiNing
Fishes That illustrate the Step Forward.

new world for the vertebrates.
Now this step is not TO be sought between
man aud the llng-breathing amphibian.
IT lies between the amphibian and the fish
There must have been an animal once that
passed from one form to the other-the
bridge between gill and lung.
The frog is a higher amphiban. We
must look to lower form. Such one is
the salamander. We must hunt for lizard
fish
Now our study of evolution leads us to
believe that from the world of the ancient
amphibians there sprang two great branches
one became land-walking form. and.
finally, man. The other became the bridge.
We know the link-form between amphibi-
ans and birds. 1t is the arch eopteryx, the
lizard bird
It's remains are fairly plentiful. We
know that it had feathers and wings, a
crocodile jaw with teeth. a long lizard tail
and lizards claws on its wing bones.
So the imagination must picture the
lizard fish as half-and-haf creature-a
thing with two lungs in it's breast and gills
on its throat
In 1885 John Natterer discovered living
creature in the Amazonian swamps that
approached these requirements. 1t had
scales and was formed like an eel. 1t had
fully developed gi!ls, and it had, also, a
fully -developed pair of lungs, and all the
other apparatus for lung breathing including
nostrils.
Scientists were still in bitter battle about
this paradox (Lepidosiren pdradorus they
called it at ast), when a similar fish was
found in Africa.
For thirty years the two creatures were
nightmares to science. Some declared
that they were fish, and the lungs belied the
finest theories Some tried to relegate
them TO the amphibans. and they upset the
whole world of amphibia.
Then came Darwin. And in ten years
the world began to accept the two creatures
as link forms
Through the fossils found then VIC learned
that in a very remote period of the worlds
story, very near to the very oldest, the only
existing representatives Of vertebrates
we're fish Then. in the carboniferous age,
millions OF years ago and yet long after
that remote fish age. the amphibiars APP
peared.
Somewhere between those two periods,
then, there must have occurred the change
of one or more Of the fishes to lung breath
ing. handwriting animals. That must
have been the great time of the lizard fish,
if the lizard fish was the link.
1t would have been fine, then, had it
been possible to discover fossil remains of
lizard fish. If one could have laid the
bones of the ancient creature alongside the
bones OF the living one, and proved their
resemblance, the world would have had
valuable, living, demonstratable proof OF
the truth of evolution,
But it seemed as if no such proof would
ever be found. None of the ancient fossil
beds showed a lizard fish.
Then. in 1869. the land Of the living link
fos,ns, Australia, produced it. And the
proof was tooth
One day Gerhart Krefft, curator Of theMu-
scum OF Sydney New South Wales received
big four-foot long carp-like fish. And this
fish had gils and scales, but also a lung
one single lung
Now as DR.. Krefft examined the mouth
of the strange monster he found. not the
ordinary fishes teeth, but only four big
teeth, with their crowns indented like the
comb Of rooster.
And such teeth had been found long
before-fossl teeth belonging to the dim
past The creature to which they had be-
longed was still unknown, but it had
always been classed with the fishes. Agassz
had christened the unknown beings Ceroto-
dus, meaning -horn breathers.'
Now DR., Krefft held in his hand freshly
captured thing tina, WAS not only lizard
fish, but actually had the teeth OF the lost
Cerdtodus
krefft did not hesitate to ma me his find
Ceratodus torsfcri. Later. when the i'm
preston OF the caudal end Of All extinct
Cerdtodus was found, and finally, when a
well-preserved skull of one was unearthed
II was proved that the most unexpected of
unexpected things had happened-a crea-
ture that had been accounted as extinct
millions Of years ago was living in the
world of to-day
Yet for twenty years the knowledge
of the living Ccrdtodus remained meagre.
We learned that the creature used his gills
TO live like fish in water during the rainy
season. while in droughts he used his lungs
to help him live amphibian-like in the
shallow pools
But no one knew about his growth from
the egg. And that was Of immense i'm
| portance for the study of evolution.
The early stages of development Of living
things in the egg are enlighlening. because
MANY creatures in this undeveloped con-
| di, ion are, so to speak, portraits of their
| ancest ors OF past epochs. Take chicken
or a canary bird ouJ Of an egg that has
only Jus, begun TO incl.nae, and we find
an object that has fI-!ike appendages and
gills.
So for years Prof Haecke! urged on the
world of science the Importance of studying
the egg Of the Cerdfodus. A, last Prof,
Richard Semon of Jena undertook the
task /, kept him away two years,
II was long fight. Floods and accidents
robbed him of the fruits of his labor time
! and again
But in tho end he succeeded in studying
| The Ceratodus stop by step. And II was
proved at last that the creature developed
not Al n fish, hut as an amphibisn passing
! through tho same stages that characterize
| frogs.
| So in the TerdiodaS We now recogni2"
! n true survivor OF the lizard-fshes. and
| thus al ancestor of mantle particular
ancestor that we have 10 thank for our
! lungs,
/ And the Cerdiodus furnishes All ilustia-
! ,on of how that lung developed from the
gills.
The African relative of the Cerdtodus