Tracing the rise of ants - out of the ground

PLoS One. 2013 Dec 26;8(12):e84012. doi: 10.1371/journal.pone.0084012. eCollection 2013.

Abstract

The evolution of ants (Hymenoptera: Formicidae) is increasingly well-understood due to recent phylogenetic analyses, along with estimates of divergence times and diversification rates. Yet, leading hypotheses regarding the ancestral habitat of ants conflict with new findings that early ant lineages are cryptic and subterranean. Where the ants evolved, in respect to habitat, and how habitat shifts took place over time have not been formally tested. Here, we reconstruct the habitat transitions of crown-group ants through time, focusing on where they nest and forage (in the canopy, litter, or soil). Based on ancestral character reconstructions, we show that in contrast to the current consensus based on verbal arguments that ants evolved in tropical leaf litter, the soil is supported as the ancestral stratum of all ants. We also find subsequent movements up into the litter and, in some cases, into the canopy. Given the global importance of ants, because of their diversity, ecological influence and status as the most successful eusocial lineage on Earth, understanding the early evolution of this lineage provides insight into the factors that made this group so successful today.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Ants*
  • Ecosystem*
  • Evolution, Molecular
  • Hot Temperature
  • Phylogeny
  • Plant Leaves
  • Soil*
  • Statistics as Topic

Substances

  • Soil

Grants and funding

AL was supported by NSF-CAREER grant 0953390; RRD was supported by the following grants: DOE-PER DE-FG02-08ER64510, NASA NNX09AK22G, NSF-CAREER 0953390. (websites: www.nsf.gov, www.doe.gov.) The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.