Graphics Reference
In-Depth Information
FIG 4.3
The distance between a
predator and its prey is critical. a: The
differences in swerving action of the
predator x results in the interception
with the prey y. b: The sharper
swerving action of the prey y allows
it to avoid the predator x that cannot
turn as quickly.
is higher than the speed achieved by the predator and the timing of the
maneuver is right, the prey will escape. The later a prey animal leaves
the swerving action and the closer the predator to it when the action is
executed, the more successful the prey is likely to be in the maneuver.
However, if the swerve is instigated too early in the chase, the turn is
more likely to be matched by the hunter and valuable distance between
hunter and prey may be lost. If the maneuver is executed too late, the prey
animal will be caught. Furthermore, if the swerve is made too early but the
distance between prey and predator is great enough, the swerve will be
matched by the hunter and will result in the two animals' paths converging.
Lunchtime.
Endurance and Economy of Energy
As some readers might know first-hand, running a marathon is very different
from running a sprint, placing very different demands on a body. Although
it may be possible for some animals to run great distances and on other
occasions to run at speed, most animals are more suited to either one or
the other. For some, their physical constraints make it possible to do only
one or the other well; it could be very difficult or even impossible to do
both. Some animals might be able to bring on a turn of speed if necessary,
but they might not have the potential to execute high-speed performance
to the same degree as others. For example, the cheetah is considered the
fastest land animal and can reach speeds of 29 meters a second at full stretch,
but it can maintain this speed for only a relatively short period of time. In
contrast, African hunting dogs are not capable of such speeds but are capable
of sustaining a hunt over very long distances and over considerable time;
indeed, they depend on stamina rather than acceleration for their success as
hunters. For the hunting dogs, shorter bursts of high speed are achievable but
are far more difficult to sustain.
Predators and prey are often fairly evenly matched in their performances;
if this wasn't so, prey animals would soon become extinct due to excessive
