Omaha daily bee., 1915-07-24

~ inc thesis defended by the late Or EDWARD Nette-
chip Of the University OF London. in posthumous
printed IN The journal Heredy. The subject
OF marriage between blood relations he notes. IL one
upon which there has been much diversity OF opinion,
doubtless often based the experiences OF certain
single families Those who object, from individual
experience. would perhaps be surprised 10 find DR..
NetueshiD that the children OF cousins some-
times show decided Improvement upon their parents.
In short he ventures TO think that the subject is one
upon which may well seek knowledge and
greater cearness Of thought lie goes on to say OK
such marriages;
The fundamental questions are % whether the
offspring OF conssnguineous display inferior
degenerate characters in larger proportions than do
the offspring OF unrelated parents? C2 II such
an effect be shown Is the appearance of these
undesirable characters attributable TO something
duced de by the union of parents related In
blood but who themselves contain no trace Of such
characters. either manifest hidden7 Or are the de-
feets only result OF both parents being tainted but
not tainted badly enough To show?
"The second question is not merely academic. For
" consanguinty produce something bad, good,
Indifferent that has never occurred before in the
geneaogy, then cousin marriage is safe But II
s only case OF inheritance from botS parents
tainted pair who have community Of blood will,
far know. be likely to have undesirable
offspring as IL they were tainted cousins; while
cousins who free from faint will be expected TO
Yield normal children.
1t must said at once that the data for answer
Ing the first question statistical grounds do not
exist, because up to the present time has
been able TO obtain sufficiently accurate returns Of the
relative number OF consaguineous and unrelated mar
riages.
AS to the second question: Are the defects some
times observed in the offspring or consanguneous
parents due TO the consangunity such or, the
other hand. TO both parents being tainted?
I'm regard 10 the de origin OF defects in chill
dren OF cousin parentage we find Charles Darwin
stating his belief as follows after having devoted
much attention to the subject: 4 hope to show in a
future work that consangunity by Itself counts for
nothing but acts solely from related organisms hav
ing similar constitution. and having been exposed
In most TO similar conditions; and a recent
authority Prof. j. Arthur Thomson OF Aberdeen. con-
siders that the idea that there be objection
to the marriage OF two healthy cousins who happen
20 fall in love with each other is preposterous' Many
similar and also some. but think diminishing
number Of opposing opinions might be cited
what. then. is the origin of the view. or at least
the suspicion, held by many. that consanguneous
unions injurious such? Without going back to
the early history OF marriage coustoms and prohbl-
tions-R task 1 not competent to undertake--t a.
think. enough say that the early Christian church
to be chiefly responsible for the existing resi-
due OF prejudice against the marriage Of cousins The
church put Its ban upon consanguineous unions-at
first in connection with the cult Of asceticsm and
celibaoy later. because II able by the sale OF
indulgences to make money by allowing consangun-
couples TO break the canoncal rules for
sderaton That this is confirmed by the sub
sequent extension of the prohibitions various affin
ties. accidental associations between persons
not related ut all by blood
OF course other causes have been and are stl at
work In both encouraging and discouraging consan-
gulneous marriages DIR. Nettleshp thinks that the
most operative cause Of hostility to these unions IL
the confusion between Inheritance of defect from
two slightly tainted but apparently normal parents
and the supposed creation OF entirely thing
by union between those of related blood For instance
II the children OF seemingly normal cousins there
should be some born deaf and dumb. surprise need
he felt IL the cousnship such, is blamed; although
inquiry might have found cases of the malady
in aoliaf tn Qtiota furfba
DR. Nettleshlp's discussion:
THAT consanguinity OF parents repeated through
many generations is compatible with the maintenance
OF high standard Of health and vigor (mental and
| bodily is demonstrated by we'll known instances
"of course. plenty of examples TO be found
| where an excessive proportion OF diseased and de-
| generate Is found among the offspring OF cousin
psrenta But these prove more than that II such
degeneracles exist In the stock they may be trans
mtted
| That inbreedng very much closer in degree and
repeated far often than anything in modern
human society does not necessarily lead to degener-
acy but quite the contrary is shown by the history o
| modern breeds of Domestic animals For Il is OF
course admitted not only that the marvellous Inn
provements effected during the last $50 years in the
breeds OF horses oxen sheep and pigs-to name only
the important kinds of live stock-have beer
reached by careful selection OF the individuals possess
In the characters desired; but that. as we are con
| stantly told, the only way TO secure and fix such
desirable characters Is to carry out this crossing Of
relations.
| 81 think, therefore. may conclude that mar
riages between cousins are as safe from the eugen
| point OF view other marriages. provided th'
| parents and stock sound.
'The difficulty. OF both for consanguineou
ana Is to decide this vital point
for obvious reasons the family history Is NOR
likely 20 be forthcoming for pair OF cousins thar
for unrelated rsir we have here part explans
ton aversion TO cousin-marriage met with II
some families. This explanation will tell with spe
elal II the disease defect is relatively rare
for then II win be likely to occur though In
latent form In two cousins than In two strangers
But " the defect apprehended be a frequent E.
tuberculosis, the chances OF the hereditary LIABILITY
TO Il being present In both parents and intensifie
in their children may be much the same whether Oh