Species biodiversity refers to the variety of living things in an area like a biome, a country, or even the whole planet. Preserving high levels of biodiversity is crucial to protecting human health and the well-being of Earth’s land, water, plants, and animals. The planet's biodiversity gives us food and shelter, supports water and nutrient cycles, and helps maintain a stable atmosphere, to name a few examples. It is important for scientists and policymakers to monitor biodiversity threats so they can create effective conservation plans.
Ecosystem services—what humans gain from a biodiverse planet—can be classified into four groups. Provisioning services include anything that can be directly obtained from nature, like fruit, timber, or natural gas. Regulating services help keep Earth’s conditions balanced, such as pollination or waste decomposition. Cultural services relate to the educational, intellectual, and social benefits of ecosystems, and supporting services help sustain the other three. All of these ecosystem services require biodiversity to function.
Ecosystems and all their components can be viewed through two lenses: their instrumental value, which is based on how helpful they are as a means to a desired goal, and their intrinsic value, the importance nature has just because it exists. Historically, human society has focused too much on instrumental value without adhering to sustainable practices; this has damaged many aspects of ecosystem health, including biodiversity.
Scientists use the term background extinction rate to represent the speed of species extinction if human actions did not exist or had no effect. They estimate that today, global species richness, or the number of different species around the world, is declining at 1,000 to 10,000 times this natural rate due to unsustainable human activity. Without significant change, this threat will continue to worsen.
Created using data from the Half-Earth Project, this map layer shows species richness and species rarity levels as a percentile rank, with one being the lowest value and 100 the highest. The species richness levels refer to the number of known unique species within each cell, and the species rarity values show how range-restricted the species are to that area. Each value in this map layer applies to a single grid cell, or about 777 square kilometers (300 square miles). All these grid cells combined form a raster, a data set made of rows and columns of cells, that includes regularly-spaced data for all of the land area on Earth.
In this map layer, many areas in Canada, Russia, and northern Europe are shades of light blue, representing high rarity and low richness levels—there are not many unique species, but those that are there are specially adapted for these regions and are seldom found elsewhere. The orange edges of Antarctica show that there are many different species, but they can be found in a wide range of locations. The white interior of the continent has low values for both rarity and richness, where very few species are known to survive. On the other hand, the dark blues and greens around the Equator and other temperate areas suggest species there have the conditions to thrive.
When a certain area has high levels of biodiversity that is being threatened by human activity, it is designated as a biodiversity hotspot. Since 2016, there have been 36 hotspots and countless initiatives working to protect the species that inhabit them. To learn more about these unique and vulnerable ecosystems, check out the Terrestrial Biodiversity Hotspots map layer.
