Evening star. [volume] (Washington, D.C.) 1854-1972, 1886-03-06
PROF. DANA ON EVOLUTION.
Facts Which Indicate that Mans An.
ceStOrs Had Tails.

In his seventh lecture ON evolution at Yale,
last Saturday, Prof. Dana illustrated his re-
marks by charts and drawings. He said the
different continents have their unity of type
which points to a unity of descent. Geology
here aids the theorist and supplies the proof
Certain animals which exist in South America
to-day, the sloth and armadilio, are pre-
eminently the type OF animals of the past,
which were much larger than those of the pres
ent- Trees are so closely like the fossils which
exist In the same continents that some
FOSSILS are called by the same names
as the living species. Some of the fossils ex-
there are all degrees and difference, and the
subsequent changes must be regarded as due
to the change of circumstances. The geological
record Is very incomplete, but 1t has been able
to demolish the distance between the living
species and their ancestors of former years
reptie-like teeth, and we have reptiles that
walk on their hind. legs like birds. The near
est bird and the nearest reptile are very far
apart, but there are lines of resemblance which
point to the fact that they were of one species,
which gives hope to the evolution.
.ra nese have great weight and we
levers in evolution ourselves. 1t is an argu-
ment in favor OF the theory OF the common
that no offspring is exactly like its parent. 1t
Is at least an open question whether variation,
II given time, Will not originate new species:
All botanists are believers in the origin OF
species from species. Change of habits through
use or disuse, is prominent way in which
change and new species occur II the mere
ceaslng to move will cause objects to grow to-
gether, may this not have been a feature in the
originating of variations and species?
Several species of ants have slaves. One
species is dependent on its slaves for it's FOOD,
the making OF its nest and the feeding OF its own
young. When they have to migrate the slaves
carry them in their jaws. This race is evidently
a new species, tor by dsuse of members they
have become entirely dependent on others,
thus forming an entirely new race.
No recent bird has been found having teeth,
but capsules have been found in the embryonic
chick. 1t is known that birds long ago had
teeth, and these have been lost through the in
a tail exist in man may point to the TACT that
some of his ancestors had a tail. One of the
splnt bones on the side OF a horses leg grew to
large size with a hOOf On it large enough to be
shod. This is simply a development of a toe
which exists in all horses in the undevelOped
state, and we are sure it existed in the ances-
tors of the horse in its developed state.
Varieties have often been produced in some
unknown way by a change of region, and also
Butterflies OF some countries are good exam
pies OF this. On opposite coasts of the Isthmus
OF Panama One-third of the shells show that
they are Of the same Species and that they
must have migrated when the isthmus was
submerged, while two-thirds show parallel
species not identically the same. The widest
differences of island from continental species
are due to migration, and sometimes entirely
different species arise from the same cause.
Darwin observes that there are rudimentary
muscles in man which are strongly developed
in the man ape, which, he says, is an indication
that they exist in this state in some OF mans
ancestors.