Ecology is the study of the relationship between organisms and their environment
Ecology is the scientific study of the relationships between the processes behind an organism’s ability to survive, grow and reproduce, and the physical/chemical components (abiotic – temperature, moisture, oxygen concentration, light availability) and the biological/living components (biotic) of their environment. Stemming from the Greek root work “Oikos” (family household), modern-day ecology has strong roots to the plant geography and natural history movements of the 1800’s.
Patterns in ecological systems are studied by ecologists at many different spatial and temporal scales – from the individual organism all the way up to the entire planet’s systems, and each level leads to a different set of questions and approaches. The systems in which these interactions occur is known as an ecosystem.
Starting from the smallest scale at which ecologists research, we have individual organisms. Individual organisms are studied to understand how their morphology (structure), physiology, and behaviour influence their ability to survive, grow, and reproduce.

Next, we have the population. A population is a group of individuals of the same species that occupy a given area, and ecologists known as population ecologists study shifts in the number of individuals in a population, as well as how these numbers change in time and space due to factors such as birth, death, immigration, and emigration.
Populations of different species living and interacting within an ecosystem are referred to as a community. Community ecologists study the factors that influence the number and types of species in a given area.
Ecosystem ecologists study how abiotic and biotic processes interact within a system and focus on the flow of energy and nutrients through both systems.
Communities and ecosystems exist in a patchwork across a larger landscape. Landscape ecologists study the factors that lead to the way a landscape looks and what consequences these spatial patterns have on the dispersal of organisms, the exchange of energy and nutrients between adjacent ecosystems, and the propagation of disturbances such as fire and disease between ecosystems.
Moving up from communities we find the level of the biome. Biomes are regions that are dominated by similar types of ecosystems, such as tropical rainforests and deserts. Ecologists at this level study patterns of species between different biomes and ask questions such as why some regions of the world are able to support more species than others.
The final scale at which ecologists research is at the level of the biosphere. All ecosystems, both land and water-based, are linked through exchanges in materials and energy. Ecologists at this level study patterns energy and nutrient transfer between different ecosystems and other earth systems, such as the atmosphere, the hydrosphere, and the geosphere.

All ecological studies follow the scientific method – that is they start with an observation which leads to asking specific, testable, questions known as hypotheses. These hypotheses are tested through experiments done in the field (in-situ), in the lab (in-vitro), or even in a computer (in-silico). The results of these experiments – a snapshot in time and space known as a dataset – are used to create a simplified representation of the system known as a model which can then be used to make future predictions. There is a trade-off as to the type of research that is undertaken; field research tends to have a lot of outside influences on an experiment that cannot be controlled but are normally more easily applied than lab or computer-based work which are able to control for those influences but cannot consider every interaction around us.
As it deals with physical, chemical, and biological processes, ecology is an interdisciplinary science. The application of ecology to environmental problems which threaten our survival as a species (human population growth, biological diversity, sustainability, and global climate change) requires an ever-expanding framework that includes historical, social, legal, political, and ethical dimensions. We can imagine that, moving forward, the field of ecology will embrace still more disciplines outside of our traditional view of science and, just like the populations of organisms of which it studies, the science is constantly evolving.
