BIOLOGY AND HUMAN SOCIETY. 69
Human Society's timber resources and, what is often of even
greater consequence, preserves the natural amenities and the
climate of a region. But as with animals, so with plants intro-
duced to a region devoid of the adverse factors that preserve
the balance of Nature, inattention to the warnings of Biology
has at times caused Human Society inconvenience. Examples
familiar to biologists are the brambles of this country in New
Zealand; the briars of Europe in Australia; the lantanas of
America in Ceylon; the nopals of Mexico in Queensland; the
thistles of Spain in the Argentine.
Biology observes that the preservation of game and the
protection of forests are activities inspired by a common purpose,
the saving from extinction through over-exploitation of animals
and plants in which Human Society happens to be interested :
that the two activities are mutually helpful, since the forester
unconsciously protects wild animals that Man might otherwise
destroy as vermin, while the gamekeeper equally unconsciously
protects wild plants that Man might otherwise eradicate as
weeds: also that Human Society is equally indebted to both for
the preservation of natural amenities and climatic conditions.
Yet the attitude of Human Prejudice towards the two activities
has been as variable and as contradictory as its attitude towards
Eugenics in the case of Man as an animal.
For the moment, however, we are less interested in the
attitude of Human Prejudice towards the various methods
adopted by Human Society to protect Man as an animal against
his uneconomic tendency to indulge in the over-exploitation of
his natural resources, than we are in the evidence at our disposal
that there is no definite line of separation between the
Exploitation and the Enslavement by Man of useful animals
and plants. In the case of animals, when a deer-forest is
delimited, not only are forestry rights denied all creatures
excluded from the area: all of the creatures within its boundaries
are reduced to the condition of prisoners. This is more evident
still in the case of a park as contrasted with a forest, and is
unmistakeable when coverts are stocked with aliens like pheasants
artificially reared. The case is really the same as regards plants
when a stretch of woodland is protected against fire and over-
felling, especially when, as with us, the area may be under larch
or spruce, as truly aliens here as the pheasant is. Indeed, in