Biodiversity 101

In our previous two discussions (Water 101 & Water & Us), we looked at the importance of water, the issues associated with its availability, and the small actions you can take to conserve it. But with all this environmental talk and discussions about saving the environment, what exactly does this mean? What precisely are we looking to save?

What is Biodiversity?

Biodiversity, or more specifically, biological diversity, is “the variety of life on Earth at all its levels, from genes to ecosystems, and can encompass the evolutionary, ecological, and cultural processes that sustain life.” Now, I know this definition may seem like a mouthful to process and understand; however, it’s all-encompassing of the depth that comes with the true meaning of “biodiversity.”

Let’s break this down:

1. “The variety of life of Earth at all its levels”: This phrase can refer to one of many ways we see the environment in “levels,” and most likely refers to the trophic levels. Trophic levels are like the “hierarchy” of living things, often represented as a “food chain.” Energy flows from one trophic level to the next through food. The energy begins with plants converting the sun’s energy into the food they need to survive.

Here we see the “hierarchy” of the trophic levels. At the bottom are “producers,” or plants or organisms that can perform photosynthesis (using the sun to make food from carbon dioxide and oxygen). Above the producers, there are “primary consumers,” simply animals that eat plants or photosynthetic organisms. All herbivores (animals that only eat plants) are primary consumers. All the levels above “primary consumers” are carnivores (they consume other animals). However, they are carnivores that have different predation pressures.

Consequently, secondary consumers are more likely to be prey than tertiary consumers. We can assume the same pattern with tertiary and quaternary consumers. For example, a lizard is a secondary consumer. The lizard is more likely to be prey than the eagle that preys on it. Most quaternary consumers are what we call apex predators. They often do not have predators other than humans.

2. “from genes to ecosystems”: This phrase refers to the aspects of life encompassing biological diversity. These components can be as small as the “genes” or as large as “ecosystems.” Both either make up life or hold life.

We’ve probably seen the super intense scenes in criminal shows where they reveal the blood sample matches the suspect’s DNA, and then the case is solved. These criminal shows give us a basic understanding of DNA; it makes us unique or different from our fellow humans. Although this is not entirely the case, the general idea is accurate (there continues to be a scientific discussion on what regions of DNA make us unique, but this topic is different from the purpose of this blog). This idea of DNA becomes very important when we look at genes because DNA is a string of genes. Genes, along with DNA, are what makeup life.

For this reason, even the most minor aspect of life, such as genes, is considered when looking at biodiversity. Genes, DNA, and other genetic components are units of life that make living things unique; it is the primary reason there is such diversity among ecosystems. While we’ve come to understand what makes up life, we need to recognize what holds life. Ecosystems are the bigger picture when looking at biological diversity. An ecosystem includes a collection of organisms (living things), whether plants, animals, or even microorganisms (such as bacteria), that interact with one another and their physical environment. Recall the above discussion about trophic levels. The different organisms at each level interacting with one another are what form an ecosystem. The more genetically diverse these organisms are, the more stable the ecosystem.

3. “and can encompass the evolutionary, ecological, and cultural processes that sustain life”: At long last, we’ve come to the final section of our definition. Here we are looking at the different processes that help “sustain life”: the evolutionary, ecological, and cultural processes.

– The evolutionary process examines how organisms have changed over time. We can explore evolution in different ways, but what’s important here is that we can discuss these “changes.” Looking at the changes allows us to understand better how our environment differs from the past.

– The ecological process includes various things that occur in the environment. These occurrences include the water cycle, the carbon cycle, photosynthesis by plants, etc. These processes, in combination, form the interactions between non-living (such as water) and living things (animals, humans, plants). The interplay between living and nonliving is crucial in maintaining a healthy ecosystem.

– The cultural process considers humans’ interaction with their environment. As surprising as it may seem, humans are a component of biological diversity. Interactions, such as water usage, agriculture, and deforestation (cutting down trees for the use of its wood) impact the environment. These interactions are a part of human culture and directly link to customs and commerce. The cultural aspect of the processes mentioned above emphasizes how humans interact with their environment.

Now that we understand biodiversity or biological diversity, we’ve come to learn what we are trying to conserve. However, we still need to know why.