North American bees are disappearing at a rapid rate, signaling a dire threat to the production of countless food sources. The Guardian reports that four common species of U.S. bumble bees have declined 96 percent in recent decades, and scientists allege that disease and inbreeding are responsible.

Honey bees have long been known to be in decline, suffering from the enigmatic colony collapse disorder, and the latest research on U.S. bumble bees only exacerbates concerns over future food production, as bees are responsible for pollinating 90 percent of the world's commercial plants, from fruits and vegetables to coffee and cotton.

While a correlation between the Nosema bombi fungus infection and the declining bumble bee populations was discovered, the culprit isn't clearly defined. One of the study's researchers told LiveScience that the data doesn't necessarily verify that the disease is driving the decline, and other factors -- like reduced adaptability to environmental changes as a result of inbreeding -- are likely at play.

The bees join other pollinating insects that have been suffering increasing declines since the end of the 20th century, including moths and hoverflies, and the U.S. findings mirror similar studies examining bee declines around the world, with everything from increasing city development to pesticide use suggested as contributing causes.

Unfortunately, insects aren't the only creatures suffering drastic losses to their populations. Tigers could be extinct in 12 years if efforts to protect their habitats and prevent poaching aren't increased. A recent study across three continents showed snakes to be in rapid decline due to climate change. Overfishing and changing weather patterns have left 12 of the world's 17 species of penguins experiencing steep losses in numbers. A recent World Wildlife Fund report found that all animals in the tropics have declined by 60 percent since 1970, with everything from gorillas to fish thinning out.

While the alarming drop in U.S. bumble bee populations is the latest news suggesting disastrous consequences from unpredictable climate change and environmental degradation, it is only a small portion of the bigger picture. Countless species are dying out at increasing rates, and the unforeseen effects from such losses could likely be devastating to the environment.