Species

The Species Problem Arises 201

Moreover, Lotsy proposes a genetic test:

Specific purity is indicated by the uniformity and identity of the F1 genera-

tions obtained by crossing the individuals to be tested, 

.^60

Thus, a species is for Lotsy an operationally applicable concept. The result is three

denitions of terms:

L: to replace the term species in the Linnaean sense, and to desig-

nate a group of individuals which resemble one another more than they do

any other individuals.

To establish a Linneon consequently requires careful morphological com-

parison only.

J: to replace the term species in the Jordanian sense, viz: mikro-

species [sic], elementary species etc. and to designate a group of externally

alike individuals which all propagate their kind faithfully, under conditions

excluding contamination by crossing with individuals belonging to other

groups, as far as these external characters are concerned, with the only

exception of noninheritable modifications of these characters, caused by the

influences of the surroundings in the widest sense, to which these individu-

als or those composing the progeny may be exposed.

To establish a Jordanon, morphological comparison alone consequently does

not sufce; the transmittability of the characters by which the form was dis-

tinguished, must be experimental breeders.

S: to designate a group of individuals of identical constitution, unable

to form more than one kind of gametes; all monogametic individuals of iden-

tical constitution consequently belonging to one species.^61

Lotsy rejects the idea of intraspecic variation in Darwin’s sense, and is of the view
that every homozygotic form is itself a species. It follows that every mixing of these “pure
forms” is the origination of a new species if that novelty persists. Moreover, he thinks that
species can be polyphyletic—they can arise more than once, because a species is formed
in virtue of its “constitution,” not in terms of its history.^62 Moreover, “nature primar-
ily can make nothing but individuals,”^63 and it can secondarily group those individuals
in various ways. Linneons are not natural, though—they are groupings formed by the
human mind. He gives an example using human races supposing that even if there were
four “pure races” arranged in army battalions we could divide them up in various ways,
according to tattoo marks given from parent to child so that each child has two marks.^64
If there has been no intercrossing, then although the individuals have changed, he
says, the constitution would remain the same and we could arrange the progeny into
those groups, but if crossings occurred, we could not assign them to the right armies.

(^60) Lotsy 1916, 24.
(^61) Lotsy 1916, 27.
(^62) Lotsy 1916, 45.
(^63) Lotsy 1916, 46.
(^64) Lotsy 1916, 47– 49.