Animals that Swim
Chapter Six: Aquatic Animals on Shalimar
Shalimar's oceans provided a comfortable environment for the
development of the Eaters (animal life forms). Stable temperatures
and plenty of Cookers (plants) made life easy for organisms that
could not make their own food.
The unicellular life forms that did not acquire chloroplasts
needed to find sources of energy so that they could continue their
life processes. Many of them would engulf protein molecules and
other life forms if they could. Some, like the amoebae on earth,
were able to change their shapes to surround and capture their
food.
Exactly how these organisms learned to
organize themselves as true multicellular animals is not known,
but some small colonies of cooperating but undifferentiated cells
exist in Shalimar's oceans today. We assume that these are intermediate
forms. We have tentatively sorted the animals that we have found
into three phyla, Trappers, who have hard outer shells and who
actively capture their food, Worms, who have segmented bodies
shaped like a piece of rope, and Acceptors, who are rooted and
who capture food as it drifts down to them.
The
reproductive process in Shalimar's animals seems chaotic to visitors
from earth. During reproduction, cells sometimes duplicate the
normal chromosomes and then do not divide, leading to cells with
double the number of chromosomes. Sometimes these cells do not
work and die, but sometimes they live. We believe that one characteristic
of Shalimar's life forms, i.e., repeated modules of identical
structures, is a result of this chromosomal duplication. Detailed information may be found
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© Elizabeth Anne Viau, 1996. This material
may be used freely for instructional purposes but not sold for
a price beyond the cost of reproduction. Please e-mail me at eviau@earthlink.net if you
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