By Noelle Hartt | 03/03/2025
Biodiversity may not be a word you hear every day, but you don’t need to be a biologist to recognize why it matters. Biodiversity – or biological diversity – exists all around us. Like unsettled land, however, it continues to wane as human activity persists.
“The word biodiversity means ‘diversity of life.’ What we have learned is that a higher level of diversity means a higher chance of survival for all species, including humans,” says Dr. Suzanne Agan, associate professor at American Military University’s School of Science, Technology, Engineering and Math (STEM).
Genetic variation, also known as genetic diversity, also plays a role in this higher chance for survival. You might assume that biological diversity gives way to genetic variability, but scientists say the opposite is true. In fact, the National Research Council explains that genetic diversity even produces biodiversity within individual species.
How Does Genetic Diversity Contribute to a Population’s Long-Term Survival?
Studies indicate that genetically diverse populations are better suited for natural selection than their less diverse counterparts. Dr. Agan uses human health as an example to illustrate this point.
“If we were susceptible to the same illnesses due to less diversity within our own genes, most of us would have perished from one or two major disease outbreaks, such as the Spanish flu.”
Even plant species benefit from genetic diversity. “Diversity in our crops means that a disease which affects one variation may not affect others, ensuring the survival of our food sources,” says Dr. Agan.
We have visible proof of why genetic diversity is important for plant species all throughout our local grocery stores.
Perhaps the most famous example is the modern Cavendish banana. The Cavendish rose to popularity only after a fungal infection led to the near-extinction of the first commercially available banana, the Gros Michel. As Panama disease ravaged Gros Michel crops in the 1950s and ‘60s, banana growers shifted their focus toward this more disease-resistant variety.
If not for genetic diversity, there would be entire generations of people who have never tasted – or seen – a banana. This is also the case for every plant and animal we consume, since all living things are susceptible to disease.
How Does Human Activity Affect Biological Diversity?
There is an obvious incongruence between industrialization and natural ecosystems. Some even consider urbanization “a global threat to biodiversity,” according to Science Direct. Ultimately, as Earth’s human population develops more acreage, our growing carbon footprint continues to displace plant and animal species.
“Industrialized nations and developing nations each have their own unique issues concerning biodiversity,” says Dr. Agan. “Urban development and manufacturing both threaten biodiversity as they inevitably lead to habitat loss and pollution.”
Still, Dr. Agan points out, conservation initiatives are not uncommon among industrialized nations, as they often rely on natural resources for international trade. Growing concerns about climate change also inspire sustainability efforts. Nonetheless, biodiversity loss remains an issue throughout the developed world.
“Developing nations tend to have higher levels of biodiversity, but fewer means to preserve and even enhance those through conservation,” Dr. Agan observes. Worse yet, non-industrialized countries are less inclined to consider the enduring consequences of their resource management.
“These nations can fall into practices that favor short-term gains,” Dr. Agan explains. For instance, conservation and agriculture have been at odds for years now. Annual tropical deforestation has reached an estimated 4 million hectares (nearly 10 million acres), according to Our World in Data.
Brazil and Indonesia alone account for most of the destruction. Each country clears a significant portion of its rainforests each year to expand agricultural land.
“Sacrificing old-growth forests is a tragedy in itself. Moreover, deforestation costs developing nations the opportunity to promote climate resilience and cultivate healthy, productive soil,” says Dr. Agan.
Between cutting down trees and compromising soil health, humans accelerate biodiversity loss in both flora and fauna. Habitat destruction displaces animal wildlife on a large scale, while soil degradation eventually creates barren land.
What Happens to a Local Ecosystem When Non-Native Species Move in?
Climate change and other forces of nature have displaced many species – both plant and animal – throughout our planet’s history. Among the greatest contributing factors behind large-scale species migrations is the human population.
Over the course of hundreds of years of international trade, humans have introduced a number of species to new regions worldwide. For example, the Columbian Exchange brought horses, pigs, cattle, and other livestock to North and South America.
“Introducing non-native species into new areas has been happening for a long time and may not cause any harm,” says Dr. Agan. She adds that “Introducing different species to different regions could be beneficial. For instance, a foreign species could fill an empty niche and help improve overall ecosystem diversity.”
Introducing new species to a region can also provide economic advantages. “Most farmers here in the U.S. grow crops that are not native but provide valuable food resources, such as tomatoes. Non-native doesn’t necessarily mean it causes harm,” Dr. Agan notes.
Still, she explains, there are cases in which non-native species threaten entire ecosystems. We refer to these threats as invasive species.
What Is the Difference Between Non-Native Species and Invasive Species?
“An invasive species is one that is non-native and also does harm to the ecosystem,” Dr. Agan observes. “For example, you need but drive around the southern U.S. to see the large areas of vines overgrown around wet areas and streambeds. Kudzu was once used to prevent erosion and now chokes out just about anything it grows around, threatening the biodiversity in those areas.”
Now, these impacted regions depend on human intervention to preserve ecosystem diversity. Without our help, invasive kudzu would monopolize limited resources. Eventually, native tree species and all the living organisms that rely on them would face endangerment.
Similarly, invasive animal species can disrupt entire ecosystems. Humans must combat these threats to prevent endemic species – those species limited to select regions – from going extinct and potentially triggering an ecological Armageddon.
Unfortunately, protecting the physical environment can quickly become a financial burden.
“Feral hogs have cost the U.S. economy millions of dollars in damages, and their population is still increasing, as they have no natural predators in most areas,” says Dr. Agan.
Wild felines also threaten species diversity throughout our country. “Feral cats have decimated bird populations across the U.S. and caused the extinctions of at least 40 species globally,” notes Dr. Agan.
Spaying and neutering pets, then, not only helps to keep cats off the streets, but also protects vulnerable bird species from endangerment.
How Is Climate Change Impacting Species Diversity Around the Planet?
Earth’s changing climate poses a threat to virtually all living organisms. The damage won’t all happen overnight, but in stages. As increasing levels of carbon dioxide contribute to climate change, plants and animals will adopt new habits in response to evolving environments.
As humans scramble to preserve global biodiversity, climate change and rising carbon emissions could also revolutionize the world of science.
Dr. Agan believes changing migratory patterns among animals will spark “an entirely new field of research.” Already, there have been massive shifts among fox populations alone.
“Red foxes are moving into more northern ecosystems and outcompeting native arctic foxes that currently inhabit those spaces. What we consider native or non-native may be very different 50 years from now,” she says.
What Is Biodiversity Going to Look Like in the Future?
Ecosystem diversity will undoubtedly fluctuate. From coral reefs to mangrove swamps and all the forests throughout the globe, humans must measure biodiversity as we work to combat climate change.
According to the United Nations (U.N.), “the risk of species extinction increases with every degree of warming.” The organization estimates climate change could eliminate as many as one million species across terrestrial, marine, and freshwater ecosystems.
What Are the Repercussions of Individual Plant and Animal Species Becoming Extinct?
Unsurprisingly, biodiversity conservation efforts focus on identifying and protecting endangered species. Due to the complexity of ecosystems, we can’t always predict the consequences of endangerment or extinction.
As Dr. Agan points out, a single species becoming endangered or extinct may not always spell catastrophe, but the threat persists, nonetheless.
“Each plant and animal, along with its environment, is part of a complex web. The loss of one will have consequences,” Dr. Agan says. If the wrong species were to disappear, the result could be “a complete collapse with a trophic cascade that wipes out many other species.”
For an example of a trophic cascade, say a species at the base of the food chain, like a native plant, goes extinct. The ultimate impact will depend on how integral the plant was to animals’ diets.
If the extinction leaves herbivores with insufficient food sources, they can quickly begin to die off. Consequently, predators higher up on the chain would have fewer resources and could then become endangered as well.
At the same time, because plants emit oxygen, the loss of vegetation further contributes to the greenhouse effect and climate change.
Consequently, biodiversity research and ongoing conservation initiatives are not only beneficial, but entirely necessary. Our physical environment is incredibly complex, with many species relying on one another for survival.
How Does Species Diversity Affect Ecosystem Services?
“Ecosystem services are the direct and indirect benefits that ecosystems provide humans,” states the U.S. Department of Agriculture’s Climate Hubs. Essentially, whenever we consume plants, animals, water, and other natural resources, we are receiving ecosystem services.
These services underscore the economic importance of our environment. Food sources in particular demonstrate just how important biodiversity conservation is. As the sustainability-focused organization FoodPrint points out, low biodiversity levels can lead to food shortages.
Fortunately, though, the opposite is also true: The more species of plants and animals we sustain, the larger our food supply will be. Accordingly, conserving biodiversity benefits both the planet and our own well-being in the long run.
What Can We Do to Conserve Biodiversity?
Conserving biodiversity is a group effort that requires participation from the entire global community. As scientists warn, plants and animals won’t be able to perform their usual roles within their respective ecosystems if populations decline too much.
Who Can Help to Prevent Biodiversity Loss?
As Dr. Agan emphasizes, we can all help preserve biological diversity to create a more stable climate. For instance, limiting the use of poisonous compounds in our day-to-day lives helps protect water, coral reefs, and other vulnerable natural resources. We can also help by:
- Removing trash from national parks, wildlife reserves, and wildlife sanctuaries
- Reducing our dependence on fossil fuels whenever possible
- Encouraging the growth of flowering plants and the trees in primary forests
Taking the time to dispose of pharmaceuticals properly is another small way we can each do our part. Researchers, wildlife managers, and politicians all play special roles as well.
Scientists must work closely with stakeholders to “access, research changes in, and protect all ecosystems,” Dr. Agan says. Wildlife managers need the best available information to understand the intricacies of complex ecosystems and make sound scientific decisions.
Scientific advisors are also invaluable to policymakers. Together, they can determine the best course of action to take for each specific location and situation, explains Dr. Agan.
“Predator conservation, for example, will look very different for red wolves in North Carolina than it will for gray wolves in Montana. Policymakers need to take a more unbiased and bipartisan approach to management.”
Environmental Science Degrees at American Military University
“The loss of biodiversity can easily be connected to our disconnect from nature,” Dr. Agan shares. To help reestablish that connection, American Military University (AMU) offers several degree programs:
- An online Bachelor of Science in Environmental Science
- An online Master of Science in Environmental Policy and Management
- An online Master of Public Policy (MPP) with a concentration in environmental policy
Faculty members are scholar-practitioners who lead students through various courses that cover topics such as ecology, our changing climate, different sciences, and the ethics and policies that help safeguard our environment. Other courses available with these programs include an introduction to sustainability and environmental management.
For more information about these degrees, visit AMU’s science degree programs page.