The science behind PREDICTS

PREDICTS will use a range of meta-analytical methods to quantify species- and community-level responses to a range of human pressures including agriculture, hunting, deforestation, introduction of invasive species and human population expansion.

Photo of a black caiman by Lawrence Hudson

Ecological attributes

Species do not all respond equally to human pressures such as land-use change, exploitation and the introduction of invasive species. PREDICTS will model how biodiversity responds to different anthropogenic pressures as a function not only of the intensity of environmental pressure, but also of species' ecological attributes. This will enable a more in-depth understanding of biodiversity loss, and allow more accurate projections that can inform conservation policy.

Some of our models will therefore include key ecological attributes of species (e.g., how large they are and whether they are geographically widespread or local endemics) in interaction with measures of anthropogenic pressures (e.g., type, intensity), to understand the response of biodiversity to different intensities of human threats.

Photo of a spider by Lawrence Hudson

Measures of biodiversity

PREDICTS will also investigate whether different components of terrestrial biodiversity respond differently to anthropogenic change. Biodiversity components of interest include: species richness, abundance, evenness, community biomass, spatial turnover and functional diversity.

Taxonomic groups

The project aims to include data from a wide variety of different taxonomic groups, including vertebrates, invertebrates and plants. Indicators of biodiversity declines have been heavily biased towards taxonomic groups that appeal to many naturalists, such as birds. Different taxonomic groups may respond differently to anthropogenic pressure, and it is important to include as wide a range of species when considering global changes in biodiversity in response to human impact.

Photo of a damselfly by Lawrence Hudson

Geographical characteristics and scales

PREDICTS will investigate biodiversity responses at both a global and local scale, including nation- and biome-specific responses. Certain geographical regions and biomes have been neglected in studies of biodiversity declines, but species responses to human pressures may vary between biomes. PREDICTS aims to include data from all terrestrial biomes and geographical regions in order to gain a more complete picture of human impacts on global biodiversity.

Photo of a grasshopper by Lawrence Hudson

Scientific aims

The PREDICTS framework will have the potential to separate the effects of different drivers of change, test whether different biodiversity components and taxonomic groups respond differently, and provide useful indicators at multiple geographical scales. We will use it to answer both policy-relevant and fundamental scientific questions such as:

  1. What are the biodiversity consequences of socio-political scenarios for 2050, including those being developed for the next generation of IPCC reports?
  2. How will different components of biodiversity respond to different scenarios?
  3. Does biodiversity decline steadily as threats intensify, or are there strong threshold effects?
  4. Does biodiversity that is known to directly underpin selected ecosystem services show unusual responses compared with broad-sense biodiversity?