Zoology
Zoology(Gr.
zoon , logos, to study) is the study of animals. It is one of the broadest fields
in all of science because of the immense variety of animals and the complexity
of the processes occurring within animals. There are, for example, over 20,000
described species of bony fishes and over 300,000 described (and many more un
described ) species of beetles! It is no wonder that zoologists usually
specialize in one or more of the sub disciplines of zoology. They may study particular
functional, structural, or
ecological aspects of
one or more
animal groups (table 1.1), or
they may choose to specialize in a particular group of animals (table 1.2).
Ichthyology, for example,
is the study
of fishes, and
ichthyologists work to understand the structure, function,
ecology, and evolution of fishes. These studies have uncovered an amazing
diversity of fishes. One large group, the cichlids, is found in Africa (1,000
species), Central and South America (300 species), India (3 species) and North
America (1 species). Members of this group have an enormous variety of color
patterns (figure 1.1), habitats,
and body forms.
Ichthyologists have described
a wide variety
of feeding habits in cichlids. These fish include algae scrapers, like
Eretmodu , that nip algae with chisel-like teeth; insect pickers, like Tang
anicodus; and scale eaters, like Perissodus. All cichlids have two pairs of
jaws. The mouth jaws are used for scraping or nipping food, and the throat jaws
are used for crushing or macerating food before it is swallowed .Many cichlids
mouth brood their young. A female takes eggs into her mouth after the eggs are
spawned. She then inhales sperm released by the male, and fertilization and
development take place within the female’s mouth! Even after the eggs hatch,
young are taken back into the mouth of the female if danger threatens (figure
1.2). Hundreds of variations in color pattern, body form, and behavior in this
family of fishes illustrate the remarkable diversity present in one relatively
small branch of the animal kingdom. Zoologists are working around the world to
understand and preserve the enormous diversity.
Reference:
Miller−Harley:
Zoology, Fifth Edition.
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