Ant Larvae: In the Spotlight

Ant larvae are generally not a hot topic. Most people don’t see them because they are hidden within the ant nest. When noticed, the young ants seem to be legless grubs passively laying around and waiting to be tended by the adult worker ants. Or are they? Let’s take a closer look at ant larvae.


Ant larvae vary in shape depending on the species of ant, but in general they are legless, plump and resemble a comma or crochet hook in shape. They have a distinct head capsule. Some are sleek,


whereas others have numerous hairs.

Larval movement:
Ant larvae are not completely inactive; they are capable of movement.

Some species of ant larvae have been shown to sway to attract the attention of passing workers in a behavior that has been described as begging.

Other species can even raise themselves off the ground. Take a look at Mark Moffett’s photograph of bulldog ant larvae begging.

If you disturb an ant colony under a rock, you can observe ant larvae alternately straightening and curling, which looks like they are throwing their heads back. Presumably they are trying to attract the attention of worker ants.

This clip is a series of photographs showing ant larvae throwing their heads back. Try to follow the larvae towards the center from slide to slide as they curl and straighten.

(Let me know if you can’t follow it and I’ll put up the stills.)

Ant larvae as child laborers:

Ant larvae do make active contributions to the colony. The weaver ants, for example, use their larvae to produce the silk needed to tie leaves together to form the nest structure.

Probably the most surprising aspect of ant larvae is that not only do worker ants bring them food, but the larvae are often sources of food themselves.

Having ultra-thin waists (petioles) makes it impossible for adult ants to move solids into their food-processing centers in the hind section of their bodies (gasters). Adult ants can only consume liquids.

Scientists have long known that the worker ants feed all solids to the larvae first for processing. The larvae were thought to chew up, swallow and pre-digest the food, and then regurgitate it back to the workers to distribute throughout the colony.

Recently, however, researchers have shown that in one species of bigheaded ants the workers actually place the food on the surface of the belly of the larvae in a special groove (larvae lay on their backs). The larvae spit out enzymes onto the food, basically drooling on themselves. After a few hours, the workers come back and pick up the slime that results, feeding some of it to the larvae and taking some for themselves. According to videos of the larvae processing bits of fruit fly, the larvae very rarely sip any of the gooey liquid while the food is dissolving; they wait patiently until the food is done and let the worker ants feed them.

Other species of ants resort to feeding on the larvae in various ways. Certain species of ant larvae have special structures that allow the workers to access the internal body fluids (hemolymph), a sort of pump or “tap.”

The so-called Dracula ants take things a step further. These rare ants get their name from the fact that they cut holes in the sides of the larvae and suck out hemolymph. Although this sounds pretty gruesome, the larvae survive having holes bitten into them and later become workers themselves.

Another odd behavior of this group is that the workers carry the larvae to their food and place them on it, rather than carrying the food to the larvae, as most other ants do. For example, instead of cutting up a caterpillar into chunks and carrying it into the nest to feed the larvae, Dracula ants carry the larvae out to the caterpillar. Once they have fed, the larvae become food themselves.

Given the evidence, you can’t help but to conclude that ant larvae are important members of the ant colony and not just passive babies waiting to become workers.



Bruno Gobin (2005) Larval begging for food enhances reproductive options in the ponerine ant Gnamptogenys striatula. Animal Behaviour vol 69: 293-299

Keiichi Masuko (1986). Larval Hemolymph Feeding: A Nondestructive Parental Cannibalism in the Primitive Ant Amblyopone silvestrii Wheeler (Hymenoptera: Formicidae). Behavioral Ecology and Sociobiology, Vol. 19, No. 4: 249-255

Keiichi Masuko (1989). Larval Hemolymph Feeding in the Ant Leptanilla japonica by Use of a Specialized Duct Organ, the “Larval Hemolymph Tap” (Hymenoptera: Formicidae). Behavioral Ecology and Sociobiology, Vol. 24, No. 2: 127-132

Keiichi Masuko (2008). Larval stenocephaly related to specialized feeding in the ant genera Amblyopone, Leptanilla and Myrmecina (Hymenoptera: Formicidae). Arthropod Structure & Development Volume 37, Issue 2: 109-117

See more about Dracula ants at Myrmecos Blog

Young Ants in the Kitchen -Science News for Kids Summary based on D. L. Cassill, J. Butler, S. B. Vinson and D. E. Wheeler (2005). Cooperation during prey digestion between workers and larvae in the ant, Pheidole spadonia. Insectes Sociaux Volume 52, Number 4: 339-343.


Ants and Salt

When my very good friend Deb Sparrow sent me this photograph of a harvester ant collecting a piece of a blue corn chip that had fallen from her lunch, I immediately took it at face value. A harvester ant carrying a corn chip seems like an obvious combination. After some research, however, I am beginning to wonder whether the ant was also interested in another, not so obvious, aspect of the corn chip.

Photograph by Deb Sparrow (near the Hassayampa River in Arizona)

Recent research has shown that certain ants collect salt (sodium chloride). Michael Kaspari, Stephen P. Yanoviak, and Robert Dudley presented different species of ants baits with varying concentrations of salt (NaCl) versus two concentrations of the standard bait attractant, sucrose solution in water.

The scientists found the ants responded to the salt solutions depending on their distance from the ocean. Ants near the ocean presumably would have more salt available, carried to the land by wind and storms. In general, the further from the shore, the more the salt solution attracted ants and the steeper the dose response.

One interesting exception, however, were ants that generally are thought of as carnivorous, for example fire ants of the genus Solenopsis. The idea is that carnivorous ants get their salt through their prey, whereas vegetarian species, like the harvester ant above, would need to supplement their diet. The researchers also found that ants of the genus Pheidole did not respond to salt. The diets of many Pheidole are not well-studied, but at least a portion are also seed harvesters.

Guess I’ll be paying more attention to ants and salt from now on. I have to say that here in Arizona our water, and thus irrigated soil, is full of salts. In fact one of our main rivers, the Salt River, is named for the natural salt springs that feed it. Maybe our natural abundance of salt is one of the reasons why we have such a variety of ants.

What do you think of ants and salt?


On the biogeography of salt limitation: A study of ant communities by
Michael Kaspari, Stephen P. Yanoviak, and Robert Dudley.
Proc Natl Acad Sci U S A. 2008 November 18; 105(46): 17848–17851.

Ants More Attracted to Salt Than to Sugar by James Parker for The Daily Californian

The biogeography of sodium limitation by Dr. Michael E. Kaspari at The AntLab. Also see link to pdfs of his papers.

Inland Ants Crave Salt, and Hurricanes May Help by John Roach for National Geographic News

Edit:  The Circus of the Spineless is now up at Greg Laden’s Blog