Graphics Reference
In-Depth Information
to locate moths in the night have become extremely sensitive, and
coats needed to insulate against intense cold have become long and
thick. It looks like nature provides the best illustration of the old design
adage that
form follows function
. Behavior is also shaped by those same
evolutionary forces that determine animals' physical aspects. Birds of
paradise demonstrate a wonderful array of displays and have developed a
particularly spectacular range of specialist feathers to enhance the effect.
Along with dancing, hopping, display flights, and swinging upside-down
from branches, the male birds have also evolved a range of distinctive calls
and songs to turn the head of any discerning female. The lyrebird has even
taken to presenting its collection of iridescent beetle-wing casings, flowers,
and seeds in its effort to attract a mate. None of this display is pointless; it
indicates in one way or another the suitability of a particular mate for the
passing on of genes.
The variety of forms these animals take is just as staggering as the variety
of life on earth. From the enormous blue whale, the largest animal ever to
have lived, to the smallest known insect,
Dicopomorpha echmepterygis
, a
parasitic wasp smaller than the head of a pin, all are subject to generational
development. They are the way they are due to an evolutionary response
to the environment they live in—their need to feed, to reproduce, and
perhaps above all else, to avoid falling prey to other animals. Nature has
provided rather elegant solutions to all these problems in a huge variety of
ways.
If you need to navigate around your environment so you know where you are
going, then eyes that provide clear color vision seem to be one of the best
options, but they're certainly not the only one. If you need to get around in a
watery medium, swimming with fins is perhaps your best bet, though even
this strategy might not be the only solution. Some insects and mammals
use limbs to row themselves through the water; the nautilus propels itself
through the oceans by jet propulsion. If you need to fly, wings would seem to
fit the bill perfectly, but once again these are not the only solution that nature
provides. Some spiders spin long, slender webs that they use to catch the
breeze, which lifts them from the ground and transports them great distances
over land or water. Admittedly, the web doesn't offer the same level of control
as a bird's wings, which means that the spider doesn't have a great deal of
choice over where it ends up, but it is undoubtedly a strategy that works. If
you need to get along on the ground, a whole range of options is open to you.
You can walk, run, slither, wriggle, hop, jump, burrow, and even swing, though
you will probably need access to a tree or two for that particular mode of
locomotion.
In considering effective and efficient modes of locomotion, size really does
matter, as with many other things in life. Because of their large body mass,
elephants do not have the ability to undertake the same scurrying action as a
rodent. Only much smaller animals are capable of such rapid movement. The
inertia inherent in the heavy legs of the elephant would demand the release
