species, a fugitive-like species, as compared to the superior species. The inferior
species is able to recover more quickly from their sudden “extinction” from certain
patches and, thus, may “evade the bulldozers” more easily whereas the chances that
the superior species will get caught in a patch that is being destroyed is greater
because of their slower movement.
Matthias use this graph instead of the previous one: As habitable space is
decreased in the example we show above, the superior population declines and
the inferior species declines. When the space has been preempted down to the level
E/CS or below, the superior species disappears and the population begins to decline
from its maximum steady-state level. When the habitable space is reduced to the
level E/CI, both species disappear from the landscape.
Still another interesting possibility exists. Let the extinction coefficient E be the
same for both species. Under a special range of choice of CS, E, and CN, only the
superior species exists at the steady state, until the fractional level of habitat has
been reduced below E * CN/(CS)^2, in the cases where this term is less than one. Our
model indicates a subtle nuance [2]: under those conditions where the fractional
level of the habitat stands between 1 and E * Cn/(Cs), only repeated disturbance can
possibly keep the inferior species in existence on this patch. Then those disturbances must not be too severe or they may speed the demise of the inferior species.
The range of frequency and severity of the disturbance are critical as one can
apparently only learn by experiment with numerical analysis. Try to show this
“window” by selecting new values for these coefficients.
A true field of science has its own unique principles. Ecology has few and the
concept of a limiting territorial size may be one of those unique principles.
Fig. 34.5
34.1 Basic Colonization Model
287
species is able to recover more quickly from their sudden “extinction” from certain
patches and, thus, may “evade the bulldozers” more easily whereas the chances that
the superior species will get caught in a patch that is being destroyed is greater
because of their slower movement.
Matthias use this graph instead of the previous one: As habitable space is
decreased in the example we show above, the superior population declines and
the inferior species declines. When the space has been preempted down to the level
E/CS or below, the superior species disappears and the population begins to decline
from its maximum steady-state level. When the habitable space is reduced to the
level E/CI, both species disappear from the landscape.
Still another interesting possibility exists. Let the extinction coefficient E be the
same for both species. Under a special range of choice of CS, E, and CN, only the
superior species exists at the steady state, until the fractional level of habitat has
been reduced below E * CN/(CS)^2, in the cases where this term is less than one. Our
model indicates a subtle nuance [2]: under those conditions where the fractional
level of the habitat stands between 1 and E * Cn/(Cs), only repeated disturbance can
possibly keep the inferior species in existence on this patch. Then those disturbances must not be too severe or they may speed the demise of the inferior species.
The range of frequency and severity of the disturbance are critical as one can
apparently only learn by experiment with numerical analysis. Try to show this
“window” by selecting new values for these coefficients.
A true field of science has its own unique principles. Ecology has few and the
concept of a limiting territorial size may be one of those unique principles.
Fig. 34.5
34.1 Basic Colonization Model
287