Article: On Ants

On Ants

The following points are made by Philip S. Ward (Current Biology 2006
16:R152):

1) Ants are one of evolution's great success stories. Arising in the
mid-Cretaceous about 120 million years ago, they now comprise a diverse
assemblage of approximately 20,000 species and have colonized most of the
world's terrestrial biomes. They impose a strong ecological footprint in
many communities in their varied roles as scavengers, predators, granivores,
and herbivores. In some tropical forests the biomass of ants exceeds that of
terrestrial vertebrates by a factor of four, and their soil-turning
activities dwarf those of earthworms. There is a word for "ant" in most
languages, reflecting their ubiquity and distinctiveness to humans. The
ecological dominance and conspicuous social behavior of ants have long
engaged the attention of natural historians. In terms of their species
diversity, relative abundance, ecological impact and social habits, ants
emerge as one of the most prominent groups of arthropods.

2) There is impressive breadth in the ecological characteristics of ants and
in the range of environments to which they have adapted. From deserts to
tropical rainforests, from grasslands to mangrove swamps, most terrestrial
habitats are tenanted by ants, and usually in moderate to high densities.
Ants are entirely absent only from polar regions and poorly insolated high
altitude locations (for example, tropical cloud forests above 2400 meters).
Nests are situated in a wide variety of sites from high in the forest canopy
to deep underground. While most ant species are rather generalized
scavengers, others have become specialized predators, seed-harvesters, and
fungus-growers. Many species avidly tend honeydew-producing hemipterans,
imbibing liquids processed through the gut of these plant-feeding insects,
and thereby acting as indirect herbivores (as well as mutualists with their
hosts).

Full text at ScienceWeek
http://scienceweek.com/2006/sw060331-4.htm

Posted by
Robert Karl Stonjek


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