1.1: Introduction to Ecology

Have you ever hiked through a forest and noticed the incredible diversity of organisms living together, from ferns to trees to mushrooms the size of dinner plates? Or taken a road trip and watched the landscape change outside the window, shifting from oak forest to tall stands of pine to grassy plains? If so, you’ve gotten a classic taste of ecology, the branch of biology that examines how organisms interact with each other and with their physical environment.

Ecology isn't just about species-rich forests, pristine wilderness, or scenic vistas, though. Have you, for instance, ever found cockroaches living under your bed, mold growing in your shower, or even fungus creeping in between your toes? If so, then you’ve seen equally valid examples of ecology in action.

Definition: Ecology

Ecology is the study of the relationships between living organisms, including humans, and ther physical environment.

Some of the phenomena that ecologists study include adaptations of organisms to the physical environment, changes in populations over time, interactions between organisms (such as a predator and its prey), the flow of energy and recycling of matter, and the biodiversity of different ecosystems.

Ecology requires the integration of scientific disciplines inside and outside of biology, such as biochemistry, physiology, evolution, biodiversity, molecular biology, geology, and climatology. Some ecological research also applies aspects of chemistry and physics, and it frequently uses mathematical models. It is important to note that ecology is not synonymous with environment, environmentalism, natural history, or environmental science. It is also different from, though closely related to, the studies of evolutionary biology, genetics, and ethology.

Figure \(\PageIndex{1}\): Images illustrating interactions among organisms and between organisms and their physical environment. Upper left: mushrooms growing on a mossy log. Image by Upper right: rolling green hills covered with wildflowers, grasses, and occasional trees. Lower left: rolling fields of dry, yellow grass with scrub-covered hills and snowy mountains in the distance. Lower right: cockroach on floorboards. Image credit: upper left, Forest by Jens Hellermann, public domain; upper right, Konza Prairie Preserve by Kgwo1972, public domain; lower left, San Raphael Grasslands by Dominic Sherony, CC BY-SA 2.0; lower right, Cockroach closeup by 邰秉宥, CC BY-SA 2.0

Biotic and Abiotic Factors

One core goal of ecology is to understand the distribution and abundance of living things in the environment. For instance, your backyard or neighborhood park probably has a very different set of plants, animals, and fungi than the backyard of another student on the opposite side of the globe. These patterns in nature are driven by interactions among organisms as well as between organisms and their physical environment. Thus, the distribution and abundance of organisms is driven by both living and nonliving factors. Biotic factors are living aspects of the environment. They consist of other organisms, including members of the same and different species. Abiotic factors are the nonliving aspects of the environment. They include factors such as sunlight, water, temperature, and nutrients.

As an example, let's go back to our shower mold. Mold is more likely to appear in your shower than, say, your sock drawer. Why might this be the case?

• Maybe the mold needs a certain amount of water to grow, and this amount of water is found only in the shower. Water availability is an example of an abiotic, or nonliving, factor that can affect distribution of organisms.
• Maybe mold feeds off of dead skin cells found in the shower, but not in the dresser. Availability of nutrients provided by other organisms is an example of a biotic, living-organism-related, factor that can influence distribution.

Why it Matters

The science of Ecology is diverse and has produced an immense body of knowledge about the world around us. It has yielded fascinating insights about the environment, our dependence upon it, and the impacts caused by human activities. There are many practical applications of ecology in conservation biology, wetland management, natural resource management (agriculture, forestry, fisheries), city planning (urban ecology), community health, economics, basic and applied science, and human social interaction (human ecology).

Organisms and resources comprise ecosystems which, in turn, maintain biophysical feedback mechanisms that moderate processes acting on living and nonliving components of the planet. Ecosystems sustain life-supporting functions and produce natural capital, such as biomass production (food, fuel, fiber and medicine), the regulation of climate, global biogeochemical cycles, water filtration, soil formation, erosion control, flood protection, and many other natural features of scientific, historical, economic, or intrinsic value. Ecology enriches our world and is crucial for human wellbeing and prosperity.

Attribution:

This article is a modified derivative of:

• "The scope of ecology." by OpenStax College, Biology, CC BY 3.0
• Why It Matters: Ecology of Living Things. Authored by: Shelli Carter and Lumen Learning. Provided by: Lumen Learning. License: CC BY