Succession

Definition

The directional, sequential change in species composition and community structure of an ecosystem over time following a disturbance or on newly available substrate. Primary succession occurs on bare, lifeless surfaces (volcanic rock, glacial till); secondary succession follows disturbances that leave soil and propagules intact (fire, logging, abandoned agriculture). In arthropod communities, early successional stages are typically dominated by r-selected colonizers—mobile, generalist insects and arachnids with high dispersal capacity—while later stages accumulate K-selected specialists, predators, and species dependent on complex habitat structure.

Etymology

From Latin successio, meaning 'a following after' or 'sequence'

Example

Following wildfire in a ponderosa pine forest, ground beetles (Carabidae) and wolf spiders (Lycosidae) dominate the early successional herbaceous stage; as shrubs and saplings establish, canopy-associated spiders (Tetragnathidae) and litter-dwelling staphylinid beetles increase in abundance and diversity, reflecting the gradual recovery of vertical habitat structure.

Synonyms

• Ecological succession
• community succession

Related Terms

• climax community
• pioneer species
• disturbance
• r/K selection
• habitat heterogeneity
• chronosequence

Usage Notes

Distinguished from seasonal or stochastic fluctuations by its directional, predictable trajectory toward increased biomass, nutrient retention, and species richness until limited by disturbance regime or regional constraints. 'Succession' without modifier usually implies ecological succession; avoid confusion with taxonomic succession (replacement of one taxon by another in the fossil record) or legal/business meanings. Specialists increasingly emphasize that 'climax' is an idealization—most communities exist in states of arrested or cyclic succession shaped by disturbance frequency.