Descent of Man [ 1871]

* Dr. W. Lauder Lindsay has treated this subject at some length in
the Journal of Mental Science, July, 1871: and in the Edinburgh
Veterinary Review, July, 1858.
*(2) A reviewer has criticised (British Quarterly Review, Oct. 1,
1871, p. 472) what I have here said with much severity and contempt:
but as I do not use the term identity, I cannot see that I am
greatly in error. There appears to me a strong analogy between the
same infection or contagion producing the same result, or one
closely similar, in two distinct animals, and the testing of two
distinct fluids by the same chemical reagent.
*(3) Naturgeschichte der Saugethiere von Paraguay, 1830, s. 50.
*(4) The same tests are common to some animals much lower in the
scale. Mr. A. Nicols informs me that he kept in Queensland, in
Australia, three individuals of the Phaseolarctus cinereus, and
that, without having been taught in any way, they acquired a strong
taste for rum, and for smoking tobacco.
*(5) Brehm, Illustriertes Thierleben, B. i., 1864, 75, 86. On the
Ateles, s. 105. For other analogous statements, see ss. 25, 107.

Man is infested with internal parasites, sometimes causing fatal
effects; and is plagued by external parasites, all of which belong
to the same genera or families as those infesting other mammals, and
in the case of scabies to the same species.* Man is subject, like
other mammals, birds, and even insects,*(2) to that mysterious law,
which causes certain normal processes, such as gestation, as well as
the maturation and duration of various diseases, to follow lunar
periods. His wounds are repaired by the same process of healing; and
the stumps left after the amputation of his limbs, especially during
an early embryonic period, occasionally possess some power of
regeneration, as in the lowest animals.*(3)

* Dr. W. Lauder Lindsay, Edinburgh Veterinary Review, July, 1858, p.
13.
*(2) With respect to insects see Dr. Laycock, "On a General Law of
Vital Periodicity," British Association, 1842. Dr. Macculloch,
Silliman's North American Journal of Science, vol. xvii., p. 305,
has seen a dog suffering from tertian ague. Hereafter I shall return
to this subject.
*(3) I have given the evidence on this head in my Variation of
Animals and Plants under Domestication, vol. ii., p. 15, and more
could be added.

The whole process of that most important function, the
reproduction of the species, is strikingly the same in all mammals,
from the first act of courtship by the male,* to the birth and
nurturing of the young. Monkeys are born in almost as helpless a
condition as our own infants; and in certain genera the young differ
fully as much in appearance from the adults, as do our children from
their full-grown parents.*(2) It has been urged by some writers, as an
important distinction, that with man the young arrive at maturity at a
much later age than with any other animal: but if we look to the races
of mankind which inhabit tropical countries the difference is not
great, for the orang is believed not to be adult till the age of
from ten to fifteen years.*(3) Man differs from woman in size,
bodily strength, hairiness, &c., as well as in mind, in the same
manner as do the two sexes of many mammals. So that the correspondence
in general structure, in the minute structure of the tissues, in
chemical composition and in constitution, between man and the higher
animals, especially the anthropomorphous apes, is extremely close.

* Mares e diversis generibus Quadrumanorum sine dubio dignoscunt
feminas humanas a maribus. Primum, credo, odoratu, postea aspectu. Mr.
Youatt, qui diu in Hortis Zoologicis (Bestiariis) medicus animalium
erat, vir in rebus observandis cautus et sagax, hoc mihi certissime
probavit, et curatores ejusdem loci et alii e ministirs
confirmaverunt. Sir Andrew Smith et Brehm notabant idem in
Cynocephalo. Illustrissimus Cuvier etiam narrat multa de hac re, qua
ut opinor, nihil turpius potest indicari inter omnia hominibus et
Quadrumanis communia. Narrat enim Cynocephalum quendam in furorem
incidere aspectu feminarum aliquarem, sed nequaquam accendi tanto
furore ab omnibus. Semper eligebat juniores, et dignoscebat in
turba, et advocabat voce gestuque.
*(2) This remark is made with respect to Cynocephalus and the
anthropomorphous apes by Geoffroy Saint-Hilaire and F. Cuvier,
Histoire Nat. des Mammiferes, tom. i., 1824.
*(3) Huxley, Man's Place in Nature, 1863, p. 34.