Poisoning Biodiversity

Biodiversity is the foundation of sustaining life in the environment. What is biodiversity? “Biodiversity reflects the number, variety and variability of living organisms. It includes diversity within a species, between species, and among ecosystems.” (greenfacts.org) Another way to explain biodiversity would be by watching this video:

Without it, species of organisms throughout the world would be susceptible to events such as disease and environmental disasters that would potentially wipe out the entire population. By having biodiversity, resistant organisms would be able to survive, and continue a population by passing on the resistant genes, eventually reaching equilibrium once more and keeping their stable niche in any ecosystem. But how are humans affecting biodiversity? Simply put, humans are affecting biodiversity in a way that could be irreversibly negative.


Humans have been on Earth for thousands of years, and have been affected by the same things as animals, like natural selection and evolution. In this modern age, humans have become immune to things that would otherwise control the ever-growing population. Unlike other organisms, we do not let the weak to fall to predators because they hinder the rest of society, but we show compassion and shelter them from dangers that nature would normally pose. As animals evolve to adapt to new environments affected by global warming, humans simply develop tools to combat their changing environments. Humans have developed methods to avoid having to be affected by nature in any way, which creates ignorance to their effect on the bigger picture. We feel as though we are separate entities from nature, not part of the web of life. The truth is that everything we do affects other organisms elsewhere, which is leading to a decline in biodiversity.


One way that humans have greatly affected biodiversity is through forestry worldwide. Through forestry, we limit the number of natural habitats available to animals. As rainforests in South America are cut down to be used as lumber and paper products, the area in which animals may live is greatly reduced. Sure, planting seedlings where trees had just been cut down may help, but not the animals that need larger trees to survive. With the long time it takes trees to grow, most animals are out of luck when it comes to forestry. With declining habitats, smaller organisms begin to become more concentrated, and become affected by limiting factors. These limiting factors cause extreme natural selection, and remove the weaker organisms from the species. By removing many of the weak at the same time, possibly important genetic information is lost forever, reducing the biodiversity of the species.


But organisms lower on the food chain are not the only ones affected by habitat loss. Organisms higher up are also affected, possibly to a greater degree. “In general the most threatened species are those that are higher up the food chain, have a low population density, live long, reproduce slowly, and live within a limited geographical area.” (greenfacts.org) As habitat is lost, and the population of smaller organisms decreases, so will the animals above it, following the concept of limiting factors. Animals that have slower reproduction cycles are given less chances of passing on genetic material to the next generation. This greatly affects the biodiversity of a species, and places the species at risk of extinction from just one disease. Ecosystems everywhere are affected by this concept of limiting factors and loss of genetic material simply because humans are determined to expand their land. While humans gain habitable space to accommodate for their growing population, animals lose their habitats and are left to nature and limits that lower their biodiversity.


Agriculture is one area that is greatly affected by biodiversity. The human race is bent on achieving productivity and effectiveness, no matter the cost. That’s why crops nowadays are being bred and genetically modified to be bigger, have a shorter growing season, and become resistant to common fungi and diseases. You might think that it’s alright, since they’re helping become resistant to certain things, but it leaves the crops to be weak to others. The domestication of plants has allowed humans to cultivate crops over many generations to determine the best one for consumption and commercial trade. Once a good subspecies is found, it’s mass-bred and cultivated, and becomes the main crop for worldwide consumption. But what does this do? It decreases the biodiversity in our crops.


One example would be the modern banana. The truth is, it’s really a Cavendish. Every banana you see in a supermarket, or that is part of the 100 billion Cavendish bananas consumed annually worldwide is exactly identical to the very first one discovered in the 1950’s. Every banana is the same; resistant to the same things, and weak to the same things. But best of all, bananas are seedless and sterile. The original one was cross-bred between two similar plants, and produced the Cavendish plant. It was continually bred through cuttings taken from the plant itself. In this way, each offspring plant is identical to the parent. But the modern banana wasn’t the same one used before. Gros Michel was the species of banana that used to be cultivated on plantations in the exact same way as the modern banana. The only difference was that the entire species was wiped out by a fungal infection called Panama disease. It sent the banana industry into an uproar. Now, the modern banana is being plagued by a more resistant strain of Panama disease, surviving through pesticides and killing previously resistant plants. In this way, the lack of biodiversity is unsafe for the well-being of any organism’s species.

But what of it? If bananas were cross-bred in the first place, and can only be reproduced by asexual means, then it was set up for destruction, right? What does that have to do with crops now? Domestication of plants and animals alike is leading to the homogenization of these species. In history, plants and animals were by natural means, to get varying offspring. Now, breeding comes down to wanted characteristics; plants that grow more fruit, cows that produce more milk, chickens that lay more eggs. Nothing is going to have the diversity of what the species did before. If any of these organisms is susceptible to a disease, chances are they are all going to be wiped out. Domesticated organisms might be facing more danger than wild ones, because of the way humans have been affecting their biodiversity.

Humans have a negative effect on biodiversity with the expansion of their land. Habitats are lost, and animals of all trophic levels are being affected through the loss of genetic material. By breeding plants and animals to fulfill the needs of humans, they are losing their biodiversity and could be facing the fate of the banana, which has as little as five years left before they’re all gone. We are causing an extreme decline in the amount of diversity and genetic material left in the world. While we’re busy finding ways to effectively clone animals, we’re not figuring out how to properly increase biodiversity. Biodiversity is a block upon which the world stands, and we’re slowly letting it erode, until the foundation is gone. Soon enough, we will all realize what we’ve done to this world and what the future will hold. We’ll have left our mark; we’ll have poisoned biodiversity.

Sources:
"Defining species: The indirect impact of humans on biodiversity"

"Scientific Facts on Biodiversity and Human Well-being"

"Loss of Biodiversity through genetic engineering"

"Can This Fruit Be Saved?"

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