While extinction is a natural part of the life cycle here on Earth, the rates at which species are dying is currently much higher than normal. Right now, we are experiencing one of the largest mass extinctions since the dinosaurs were wiped off the Earth. This crisis of extinction will have a ripple effect of consequences for our ecosystems as we see more and more species die. While the role of a species might not be evident, each plays in integral part in maintaining the balance of ecosystems and functions of our environment. Without them, there can be devastating impacts on our world.
While all species are important to the balance of an ecosystem, it is important to note that some are more important than others. A keystone species is one that an ecosystem largely depends on, and if it were to be removed, said ecosystem would change drastically. There are five recognized categories of keystone species: predators, modifiers, prey, mutualists, and hosts. Occasionally, a species will fit into multiple keystone categories.
Predators: control the population, keeping environments and habitats open to species
Modifiers: “ecosystem engineer” physically change their environment
Prey: act as a food source for predators
Mutualists: “link species” provide mutually beneficial interactions, usually pollinators
Hosts: typically things like plants and trees that provide shelter for other species
Loss of a Predator
The loss of a predator in an ecosystem causes what zoologist Robert Paine refers to as Trophic Cascade. This scenario changes the dynamic of the entire food chain and can directly impact ecological structures. For example, if a carnivorous predator becomes extinct, their prey (most likely herbivores) will increase in numbers as they are no longer hunted for food. In turn, this will cause a stark decrease in whatever plant-based food the herbivore eats for survival. This chain-like reaction can go on and on throughout the entire ecosystem, as everything is connected. The effects of trophic cascade can be reversed
Loss of Pollinators
Pollinators play a crucial role in creating biodiversity of plant life – a feature of an ecosystem that is at the root of the food chain. These species include, but are not limited to, birds, herbivores, and insects. The plants that these pollinators facilitate growth are important because through photosynthesis, they create the oxygen we need to survive. One pressing issue recently is the rapid decline of bees worldwide. Bees are a key pollinator species for almost three quarters of the plants humans eat to survive, contributing to not only crop levels, but to the economy as well.
The world needs a variety of species to sustain any ecosystem, from the tundras to the rainforest. It is crucial to protect these vital species from extinction in order to preserve our world as we know it now. A large reason for the mass extinction rate is human impact on climate change. There are vast ways you can stop the sixth mass extinction, from reducing your carbon footprint, to eating less meat, or being more conscious of where you buy produce. Small steps pave the way to preserving our planet and its diversity of life.