Ecology: Organism-Environment Relationships & Key Concepts
What is Ecology?
Ecology is the scientific study of the relationships between organisms and their environment. The environment includes the physical and chemical conditions as well as the biological or living components of an organism’s surroundings. Relationships include interactions with the physical world as well as with members of the same and other species.
Historical Roots of Ecology
Ecology has its origins in natural history and plant geography. Over the past century, it has developed into a science with roots in disciplines as diverse as genetics and systems engineering. The study of ecology dates back to the ancient Greek scholar Theophrastus, a friend of Aristotle, who wrote about the relations between organisms and the environment. Other key figures include Friedrich Warming (plant associations, plantesamfund), Charles Darwin (evolutionary insights from the Beagle voyage), and Raymond Lindeman (The Trophic-Dynamic Aspects of Ecology).
Branches of Ecology
- Behavioral ecology: The study of the behavior of an organism in its natural habitat.
- Community ecology: The study of the living components of ecosystems; description and analysis of patterns and processes within the community.
- Conservation ecology: A synthetic field that applies principles of ecology, biogeography, population genetics, economics, sociology, and other fields to the maintenance of biological diversity. Also called conservation biology.
- Ecosystem ecology: The study of natural systems with emphasis on energy flow and nutrient cycling.
- Evolutionary ecology: Integrates the study of evolution, genetics, natural selection, and adaptations within an ecological context; provides an evolutionary interpretation of population, community, and ecosystem ecology.
- Global ecology: The study of ecological systems on a global scale.
- Landscape ecology: Study of structure, function, and change in a heterogeneous landscape composed of interacting ecosystems.
- Physiological ecology: Study of the physiological functioning of organisms in relation to their environment.
- Population ecology: Study of how populations grow, fluctuate, spread, and interact intraspecifically and interspecifically.
- Restoration ecology: Applying principles of ecosystem development and function to the restoration and management of disturbed lands.
- Systems ecology: The application of general systems theory and methods to ecology.
- Urban ecology: The study of the ecology of organisms in the context of the urban environment.
Organisms and Their Environment
The physical and chemical conditions surrounding an organism, such as ambient temperature, moisture, concentrations of oxygen and carbon dioxide, and light intensity, all influence basic physiological processes crucial to survival and growth. An organism must acquire essential resources from the surrounding environment and, in doing so, must protect itself from becoming food for other organisms. It must recognize friend from foe, differentiating between potential mates and possible predators. All of this effort is an attempt to succeed at the ultimate goal of all living organisms: to pass their genes on to successive generations.
Key Evolutionary Concepts in Ecology
- Natural selection: The differential success (survival and reproduction) of individuals within the population that results from their interaction with their environment.
- Evolution: The change in gene frequencies through time resulting from natural selection, producing cumulative changes in the characteristics of a population.
- Adaptation: A genetically determined characteristic (behavioral, morphological, or physiological) that improves an organism’s ability to survive and reproduce under prevailing environmental conditions.