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Abstract Behavior is shaped by genes, environment, and evolutionary history in different ways. Nest architecture is an extended phenotype that results from the interaction between the behavior of animals and their environment. Nests built by ants are extended phenotypes that differ in structure among species and among colonies within a species, but the source of these differences remains an open question. To investigate the impact of colony identity (genetics), evolutionary history (species), and the environment on nest architecture, we compared how two species of harvester ants, Pogonomyrmex californicus and Veromessor andrei, construct their nests under different environmental conditions. For each species, we allowed workers from four colonies to excavate nests in environments that differed in temperature and humidity for seven days. We then created casts of each nest to compare nest structures among colonies, between species, and across environmental conditions. We found differences in nest structure among colonies of the same species and between species. Interestingly, however, environmental conditions did not have a strong influence on nest structure in either species. Our results suggest that extended phenotypes are shaped more strongly by internal factors, such as genes and evolutionary history, and are less plastic in response to the abiotic environment, like many physical and physiological phenotypes.
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Small Mammal Exclosure Study (SMES) Ant Data from Chihuahuan Desert Grassland and Shrubland at the Sevilleta National Wildlife Refuge, New Mexico (1995-2005)
Animal consumers have important roles in ecosystems, determining plant species composition and structure, regulating rates of plant production and nutrients, and altering soil structure and chemistry. This is data for numbers and species of seed harvester ant nests mapped from each of the SMES study plots. Seed harvester ant nests were mapped on each of the study plots once each year in the autumn. Ant nest maps were drawn on to pre-designed plot diagrams. Each nest was located on the diagram in reference to one of the 36 vegetation quadrat marker posts. The distance from the post, direction from the post, and species name were plotted on the map diagram. Data such as total numbers of nests of each ant species, and spatial arrangement of nests, were then taken from the diagram maps. The following question was asked: Do small mammals interact with other herbivore and granivore consumers enough to affect the species composition and abundances of other consumers such as ants?
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- Award ID(s):
- 1655499
- PAR ID:
- 10424187
- Publisher / Repository:
- Environmental Data Initiative
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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