5 Systematics and Evolution
What Is Systematics?
The extent to which progress in ecology depends upon identification and upon the
existence of sound systematic groundwork for all groups of animals cannot be too
much impressed upon the beginner in ecology. This is the essential basis of the whole
thing; without it, the ecologist is helpless, and the whole of his work may be rendered
useless.
—Charles Elton, Animal EcologyIn the previous chapter, we briefly introduced the concept of systematics. However, we
will not be able to talk about most of the fossils or animals in the rest of the book if we do not
review the basic concepts of systematics and the major breakthroughs in systematic thought
that have occurred in the past decades. Of all the topics in biology, systematics is the least
understood by the general public, yet it is one of the most essential.
Most people are vaguely aware that there is a scientific system for naming and classify-
ing organisms. This field is known as taxonomy. Most scientists who name and describe new
species of animals and plants have to be familiar with its rules and procedures. But systemat-
ics is broader than just taxonomy. Systematics is “the science of the diversity of organisms”
according to Ernst Mayr (1966:2) or “the scientific study of the kinds and diversity of organ-
isms and of any and all relationships among them” in the words of George Gaylord Simpson
(1961:7). Systematics includes not only taxonomic classification but also determining evolu-
tionary relationships (phylogeny) and determining geographic relationships (biogeography).
The systematist uses the comparative approach to the diversity of life to understand all pat-
terns and relationships that explain how life came to be the way it is. In this sense, it is one
of the most exciting fields in all of science.
Taxonomists and systematists may not be as numerous or well funded as other kinds
of biologists, but everything else in biology depends on their classifications and phylog-
enies. If the physiologist or doctor wants to study the organism most similar to humans,
taxonomists point to the chimpanzee, our closest relative. If ecologists want to study how
a particular symbiotic relationship developed, they depend on the systematist for accurate
classification of their organisms. Systematics provides the framework or scaffold on which
all the rest of biology is based. Without it, biology is just a bunch of unconnected facts and
observations.
Today, taxonomists are becoming scarce as funding dries up or goes to more glamor-
ous fields that use big expensive machines. But this starves science at its heart. The humble
systematist, collecting specimens in the field on a shoestring budget or analyzing specimens
in museum drawers and jars, may not be as famous as the behavioral ecologists, watch-
ing animals in the wild, or molecular biologists with the white lab coats and million-dollar
machines, but their work is just as essential. One of the hottest topics today, biodiversity, is the
fundamental domain of the systematist. Many people are worried about how rapidly we’re