Lasting signature of forest fragmentation
A universal truth of ecology is that field experiments never unanimously support theory. This is not (always) because ecological theory is poorly developed or experiments poorly executed, but because ecology is a complex science dealing with variation at every biological level from individuals to biomes. When exceptions are the rule, explaining variation in responses among taxa and locations becomes the goal, particularly for theory that informs conservation. On page 1236 of this issue, Betts et al. (1) contribute to a particularly important debate: why the biological effects of forest fragmentation are so variable among species and places. They present evidence that historical deforestation (from glaciation, fires, hurricanes, or anthropogenic clearing) yielded communities that are more robust to modern forest fragmentation (from logging, burning, or development).
| Anna Hargreaves |
6 dec, 2019 |
Habitat fragmentation caused by human activities has consequences for the distribution and movement of organisms. Betts et al. present a global analysis of how exposure to habitat fragmentation affects the composition of ecological communities (see the Perspective by Hargreaves). In a dataset consisting of 4489 animal species, regions that historically experienced little disturbance tended to harbor a higher proportion of species vulnerable to fragmentation. Species in more frequently disturbed regions were more resilient. High-latitude areas historically experienced more disturbance and harbor more resilient species, which suggests that extinction has removed fragmentation-sensitive species. Thus, conservation efforts to limit fragmentation are particularly important in the tropics.
| By Robert J. Fletcher, et al. |
Dec 6th, 2019 |
