Vision: A Resource for Writers
Lazette Gifford, Editor
zette@sff.net

Creature Building 101:  Part 3

By Marilyn Glazar
2004, Marilyn Glazar


Part 1

Part 2

By now you know a lot about how your creature interacts with its surroundings and other creatures.  Just in the process of creating this creature you may have firmed up a lot of your ideas about how your world works and what it is like.  What you need now is a better idea of the social interaction between it and others like it, and a clear image of it.  This issue we'll work on family relationships.  After all, that's what reproduction is all about.

It's a familiar story.  Boy meets girl.  Boy and girl exchange genetic information.  Baby makes three.  When it's put that way it seems a little clinical, but that's the bare bones of human sexuality.

Of course, it doesn't explain everything.  It doesn't explain what sort of courtship rituals have to take place first or how the children are raised or what type of communication system might be set up within the species to help it do these things.  It doesn't describe the process of raising the children or how long this might take.  All of these things are part of reproduction.  All family relationships fit within this picture.  All human relationships are influenced by this picture.  When most people think about sex, they aren't thinking of these things, but in making up your creature, the mechanics of genetic exchange (the hot and sweaty stuff) are much less important than its consequences.

Still, the mechanics are a component.  In people, the genetic exchange usually requires physical contact.  In a great many fish, the exchange takes place when the male fertilizes eggs that the female has already deposited outside of her body.  In plants, the pollen is carried to the egg by the wind or an unrelated creature.  Sometimes the act of sex is intimate and involved and sometimes the partners don't even know each other. 

Most creatures who participate in sexual reproduction on this planet have two sexes, but that doesn't have to be the case for fictional creatures.  A type of creature could theoretically have three or more separate sexes.

In some animals, environmental factors influence whether the offspring will be female or male, while genetics determine this in others.  Sometimes creatures can change gender when there is an imbalance in the local population.  In some creatures the female is larger and in others smaller than the male.  Sometimes outsiders can't tell a female from a male.

In fact, genetic exchange may not take place at all.  Some creatures have only females, who produce young identical to them.  Some single-celled creatures divide to reproduce, and a few larger organisms can reproduce by pinching off small pieces of themselves.  Sometimes a type of organism is capable of exchanging genes with others but reproduces without doing so unless environmental pressures get uncomfortable.  In the social insects, only a few individuals get to reproduce while everybody else spends their time raising the young and taking care of the group.

In some simple plants, there is an alternation of generations.  Ferns, for example, produce spores through an asexual process.  These spores germinate into tiny plants that look nothing like adult ferns.  The tiny plants make sperm or eggs.  The sperm and egg of separate plants fuse and multiply to make ferns.

Whether sex is used to produce the young or not, there are two popular methods used to deal with them.  The first is to make lots of them and let them fend for themselves.  The young may be weak and inexperienced but if you produce enough of them, then one or two are bound to survive.  The second is to produce very few offspring but use a lot of resources to make sure that they get to be adults that can produce more offspring of their own.  We'll take a look at one of each type and then examine a fictional creature.

The typical garden aphid is a voracious plant predator that has specialized mouth parts designed to suck the juices out of plants.  To the gardener, it seems as if a population of these pests can spring up practically overnight.  There is a reason for that.  The typical garden aphid is a female.  She produces female offspring asexually and does so at an alarming rate because no energy is wasted in trying to find a mate.

Eventually, either the weather starts to get cold or the plant supporting the aphid population dies.  When this happens, a few males are produced.  The males mate with the females and when the resulting eggs are laid they contain a combination of genetic information from the males and the females.  All of the offspring produced by aphids are left to fend for themselves.  As aphids aren't very complex, they are born knowing everything they need to.

Ruby-throated hummingbirds are very complex by comparison.  They migrate south for the winter every year.  This species has both males and females.  In the spring the males arrive at the mating grounds earlier than the females and scout out breeding territory.  When the females arrive they choose a male to mate with.  A male may mate with several females per season.  After mating the female builds a complex nest, lays two eggs, incubates the eggs, and then forages for and feeds the defenseless hatchlings.  Only two offspring are produced and the female spends a lot of time caring for them.  When they leave the nest they are capable of fending for themselves.

For an example of a creature that spends even more time and energy raising its young than a hummingbird does, it's hard to beat a human.  A great many science fiction aliens are based on the human model with just a few slight twists.  While this does elicit some criticism, especially from those who aren't fond of science fiction, it is one way to create empathy between readers and alien characters.  For an example of reproduction in one of these types of creatures, let's look at the Newcomers from the television show Alien Nation that aired in the late '80s and early '90s.

One reason the Newcomers make a good example is that the series investigated the reproduction of these aliens quite extensively when the Fransisco family had a baby.  Often in science fiction and fantasy, an alien creature doesn't get enough attention in the story line to accommodate a close look at reproduction.

A Newcomer family consists of two parents, one of each gender, children, and grandparents.  The entire family is expected to take part in the raising of the children, which seem to age about like human children even though the aliens live a lot longer.  The female is impregnated and, before gestation is complete, the male takes over incubation, much the way male seahorses incubate their eggs in a pouch.  Both parents exhibit many of the human side effects of pregnancy at one time or another.  Everything from swollen ankles to unusual cravings was depicted in the show and lent both levity and depth to the characters' interactions.

Not every creature needs to have its sex life laid bare before the audience.  However, if this area of creature interaction isn't at least investigated by the author, then the risk is that every unusual creature will be assumed to have a personal life identical to its earthly counterparts.

Additional information:

Video:  David Attenborough's The Private Life of Plants: Putting Down Roots.  Turner Home Entertainment.

This is a great find if you can get your hands on it.  Your local library might have it.  It shows plant reproduction in a very fun and detailed way.

Web Site: http://www.backyardnature.net/animals.htm

This has some great general information about everything from amphibians to segmented worms.  It includes general reproductive information.

Web Site:  http://biology.about.com/library/weekly/aa090700a.htm

This site explains a little about asexual reproduction and includes a few pictures of creatures and links to more information.

Web Site:  http://www.rubythroat.org/RTHUReproductionMain.html

This describes hummingbird reproduction.

Web Site:  http://www.geocities.com/tellytyme/aliennation.html

Here is some general information about the TV series Alien Nation.  You can also buy a DVD or VHS of it here.