One of nature's most successful designs has to be the ant. Judging by their numbers and the number of species occupying different niches they are one of evolution's biggest success stories. It is estimated that they account for about 10 percent of the biomass in some environments and 10 percent of the carbon dioxide in the air. All ants are, to some degree, social. A nest of ants can be considered a “super organism” with the individuals functioning as individual cells. Their interactions with each other and the environment are incredibly complex and in many cases not well understood.
They are also the ultimate gangsters. I have seen praying mantises, tiger beetles and jumping spiders all defer to a single, often much smaller ant, rather than bring down the wrath of her entire pack.
Worker ants are all sterile females. About the only time you are likely to see a male is during their nuptial flight, often thousands or millions of winged males and females leave the nest intent on establishing their own colonies. Once paired, they seek a suitable site and shed their wings.
Identifying them as to species is a job for an expert with a microscope and a set of dichotomous keys, complex documents in which you are offered a series choices, progressively leading you to a final answer. A simple one to discern to which order an insect specimen might belong, can be found at www.amnh.org. The best book I have found on the critters is the Pulitzer Prize winning Ants by Bert Hölldobler and Edward O. Wilson.
In my own backyard, I can discern several species of ants. There are some partially brown ones that tend aphids for their honeydew as a dairy farmer tends a herd for milk. There are slave makers which capture the brood of a different species and use them as workers to support themselves. There is a small variety which bores into my strawberries as they ripen. Right now I am fighting a nest of carpenter ants that is trying to eat me out of house and home, literally.