Some great questions about ants were submitted to the AskAnt Team by student Jinho Lee from California. Here they are, with replies:
If ants were not historically small, at which point in civilization were they larger?
The first thing I would mention is that the "history" of ants is much longer (over a thousand times longer!) than that of humans. In other words, the whole history of human civilization is just a "blink of an eye" relative to ant history, so it doesn't really make sense to ask "at which point in (human) civilization?". The first ants are believed to have originated between 130- to 150-million years ago. The oldest known ant fossils are dated at about 110-million. Ant fossils are generally in the same size range as most modern ants. But, note that modern ants range greatly in size, from barely over 1 millimeter (mm.) to over 30 mm. in length. There are a few fossil ants even bigger than this, but these are relatively recent, and not ancestral, "only" about 30-million years old.
Can ants see shapes and colors?
The visual abilities of ants vary widely. Large-eyed ants such as Gigantiops & Pseudomyrmex perceive movement and shape well, but their color perception has not been carefully investigated. It is generally believed, but not well documented, that ants with good vision probably have about the same spectrum of color sensitivity as honeybees, i.e., they see ultraviolet, but not red. Many ants, such as small Acropyga & Hypoponera species have poorly developed eyes, and do not perceive visual images, only light, dark, and possibly motion.
What type of bug did the ant descend from?
Ants and wasps both belong to the insect order Hymenoptera (wasps, bees, sawflies and relatives) and all are descended from a common wasp-like ancestor. Based on the predominant appearance of fossil and modern Hymenoptera, it seems likely the common ancestor was more like what we would think of as a wasp than an ant.
What age are ants when they first start to contribute to the colony?
Probably the better way to ask this would be "at what stage do they start to contribute?". In one sense, they start young, as larvae, because adult ants have a very narrow esophagus and cannot eat solid food, while larvae have a larger gullet and can swallow and digest chunks of food. Many ant larvae regurgitate predigested or pre-chewed food to the workers (sort of like a mother bird feeding its young, in reverse), thus contributing to colony nutrition. As soon as ants reach the adult (typical ant) stage, they begin colony work - taking care of the young, cleaning and building the nest, and eventually foraging and defending the nest.
In your opinion, do you think that an ant colony that lives in the ground is more likely to survive than ants that live in a tree or ground level?
It depends -- Different species of ants have habits and body adaptations that help them survive in particular habitats. An arboreal ant species survives best up in the trees, but a blind, subterranean ant species would shortly die if it tried to survive up in a tree. A large variety of ant species have been successful in both environments (but different ones in each) .
How can ants tell the difference between intruder ants and ants in their own colony?
Ants have a keen sense of smell, and (like our much better known pets, dogs) can recognize individual and colony (family) odors that help them distinguish nestmates from outsiders.
Explain "aphid" and "myrmecophilous".
Aphids are plant-sap-feeding insects that have a peculiar problem; They have so much sugar in their diet that they excrete sugar water as a waste product. Many ants like sugar as an energy source, so they gather and drink this aphid "sugar-urine" (properly called honeydew) from the aphids (or from related insects with similar secretions, such as scale insects and mealy bugs). Some aphids, etc. even live inside ant nests under ground, and are moved around by the ants to fresh roots, to drink sap and make the sugary waste product for the host ants. The ants even take care of the aphids' eggs. These kinds of aphids are described as "myrmecophilous" (Greek for ant-loving).
Many other sorts of insects, mites, spiders and millipedes may be found in ant nests. When the ants' nests are the are primary habitat of these other insects, these ant "house guests" are called myrmecophiles.