All opinions are my own and do not necessarily reflect those of Novo Nordisk.
Among my personal top list of things people really should be more worried about with respect to how we’re changing the environment, the decline of bees is close to number one. On some days, like when I’m biting into a delicious Rainier cherry or a luscious peach, the decline of bees is number one. And I’m not saying this topic hasn’t gotten any press or concern. On the contrary, there’s been plenty. I just also think it should have more.
So imagine the jolt to my already heightened sense of worry when I saw the following two studies. This one, in Nature (abstract only, article behind a paywall), puts forth a theoretical model of what happens when a species goes “functionally extinct.” By this, the authors mean the point at which the number of members of a given species in an ecosystem declines to the point that other species are affected and may themselves go fully extinct. It turns out that in interconnected food webs, as a given species declines in numbers, it affects other species’ overall survival as well, and that most often the species going really and truly extinct is not the one initially declining.
I think of this situation as being kind of like playing in a massively multiplayer online role-playing game like Star Wars: The Old Republic, and you’re in a team with several others, each of whom has his or her role. Often the healer of the party gets damaged quickly in a fight, but they’re not the first one to go down. Instead, it’s the damage-dealing specialists who find themselves getting beat up and dying when the healing falters. The team, the network, relies on every member functioning fully to succeed, and reducing performance by one part of the team can have unintended consequences.
Well, that was a tortured analogy.
But the point with respect to bees is how just the decline of bee populations alone may be having cascading effects on the ecosystems in which they operate.
Another take on the importance of different species and diversity in networks comes from this study in the Proceeding of the National Academy of Sciences (USA) (abstract only, article behind a paywall). In this situation, the researchers tested the idea that plant community and insect networks are robust enough to survive the loss of individual species. They located subalpine meadow plots and carefully removed all members of a single pollinator species and asked what would happen. Network robustness theory would suggest other pollinators would take the place of the removed species, which previously served a specific niche. And this happened. However, the overall health of the plant community nevertheless appeared potentially threatened since this meant pollinators carried more types of pollen, leading to less efficiency in pollinating any given plant species.
These studies are just two of many that describe the unexpected and unintended consequences of changes in ecosystem communities. All kinds of changes. Like the decline of frogs and other amphibians, which I also worry about. My personal bias towards worrying about bees probably stems from my perception of the crucial role they play in so many functions, both for humankind in specific and ecosystems in general. The Nature paper also suggests the scary thought that we might be missing the forest for the bees, and the real impact of bee declines has already happened in the extinction of other, interconnected species which we may never know about, because they might already be gone.