In yet other cases the chemical structure of a hormone may differ even in closely related species, a common situation for complex protein hormones. In contrast to general endocrinology, which emphasizes similarities, usually among mammals, comparative endocrinology has a much broader focus that includes field and environmental endocrine studies, evolutionary studies, and behavioral endocrinology in many different animal systems. Many people become interested in endocrinology by trying to answer mechanistic questions about how physiological and biochemical events are controlled in organisms. The nervous and endocrine systems together provide integrated control of all physiological events in animals. Endocrinology helps us to understand how control systems coordinate developmental and functional events in organisms so that these biological events can proceed in an orderly way.
Endocrinology provides the basic information on which much of pharmacology is based.
As understanding of endocrine disorders improves, the potential for designing good treatment options also is improved. In many cases, specific animal models are very useful for studying particular problems or disorders in the laboratory, or in serving as sources of ideas for novel treatment possibilities. Thus, common laboratory rats aren't always the best models for all medically relevant research. Comparative endocrinologists may be either field or laboratory-oriented and this determines some aspects of how they spend their time. Hormone measurements, studies of the receptors that bind hormones in the tissues, and measurements of hormone effects are all examples of laboratory assessments commonly used by endocrinologists in their research.