Introduction to Ecology

Together on this channel we have begun to learn a lot about living organisms. We learned about

tiny microorganisms in the microbiology series. We learned about plants in the botany series,

mushrooms in the mycology series, and animals in the zoology series. We’ve begun to learn

about the Earth itself in the geology series. But what if we wish to consider all of these

things at once? Then we would be studying ecology. Ecology is a science that describes

how the organisms that populate this planet interact with each other and their physical

environments. These environments vary, depending on where we are – from the oceans to the forests,

and from the deserts to the mountains. The scientists who study these relationships between

organisms and their environments are called ecologists, and ecology itself is considered

a branch of biology. This field is incredibly broad in scale, as ecologists can choose to

study the individual organism itself, populations or communities of organisms, large ecosystems,

or even the entire biosphere as a whole, which is a word that refers to the regions of the planet

occupied by living organisms. They can specialize even further, focusing on genetics, plant and

animal physiology, biodiversity, or conservation. As we are beginning to understand, the Earth can

be broken down into distinct “spheres”, such as the atmosphere, lithosphere, cryosphere, and

biosphere. We define the atmosphere as an envelope of gases surrounding the planet, making it

habitable for life. The lithosphere is the rigid outer part of the earth consisting of the crust

and upper mantle. Over geologic time scales, the lithosphere determines how much land is available

for living organisms to inhabit and where that land is located geographically. The cryosphere

is the part of Earth’s surface characterized by frozen water. Its expanse changes over time

and this is an important factor in maintaining a habitable climate. And then the biosphere we

described a moment ago. These spheres are dynamic and can influence one another, so the better

we understand interactions within individual spheres, the more equipped we are to understand

how they all work together, as an entire system. But let’s zoom back in for a moment. Within any

given physical environment, ecologists seek to study both the types of organisms present

and their abundance. By monitoring these factors over time, ecologists can track

the general trends and well-being of the ecosystem. For example, as climate changes,

the numbers and types of organisms may change too, in order to adapt to changing conditions.

This might result in a positive or negative change depending on the species, and as a whole,

the ecosystem could be accordingly fortified or placed in jeopardy. The more we know and

understand about interactions between organisms and their environments, the better we will be

able to address any consequences that arise. Ecology does not encompass only the outdoors, as

many might assume. What about mold in your kitchen or shower? Or, if you’re an athlete, the dreaded

athlete’s foot fungus that you can pick up in a locker room? These are also examples of ecology in

action. Factors that can affect the distribution of organisms can be biotic or abiotic in nature.

Biotic refers to the living factors, which can include animals, plants, bacteria and fungi – like

the athlete’s foot fungus. The fungus is living, but how did it grow in the first place? Water!

Availability of water is abiotic, or a non-living factor. These are physical or chemical in nature,

and they also impact an ecosystem. A few other examples include air, soil, and sunlight.