Yes, ants do molt. As members of the phylum Arthropoda, ants are among the vast number of animals that molt. In fact, ants undergo molting multiple times in their life cycle as they develop from larvae into mature adults.
In this article we’ll define molting and discuss when, why, and how ants molt.
What Is Molting?
Molting is the biological process in which an animal sheds and replaces a part of its body, typically an outer layer or covering, at specific points in its life cycle. This includes the shedding of hair, horns, skin, and many other parts.
When Do Ants Molt?
Ants exclusively molt during the larval stage of their development. During this stage, ants take the form of larvae, worm-like creatures that look nothing like the ants we know. These larvae have no eyes, limbs, and can only really do one thing, eat. They rely on workers for a constant supply of food which they gobble up to grow rapidly. As they do so, they molt several times to accommodate changes in size.
Why Do Ants Molt?
Ants molt or undergo ecdysis to grow. Unlike us humans, ants don’t have soft flexible skin but instead have hard rigid exoskeletons. These exoskeletons don’t stretch and therefore, eventually become barriers for development as they fail to support the physical changes in the larval body. Thus, as ant larvae grow, they have to molt and shed their exoskeletons otherwise, they’d get crushed and fail to develop.
As such, molting permits metamorphosis. It is through the whole molting process that larva turns into the pupa which eventually develops into the adult ant.
How Do Ants Molt?
When an ant larva grows too big, stretch receptors in the body trigger the release of hormones which subsequently trigger molting. The process then starts when epidermal cells respond to the increase in the hormone ecdysone which causes apolysis or the separation of the cuticle from the underlying epidermis.
After that, the epidermal cells then secretes molting fluid, and a special lipoprotein, the cuticulin layer, which eventually becomes part of the new exoskeleton’s epicuticle. Once this layer is formed, the molting fluid becomes activated and breaks down the old cuticle to recycle amino acids and chitin which eventually become the procuticle or inner layer of the new exoskeleton.
When the new exoskeleton is ready, the larva sheds the old exoskeleton by contracting its muscles and taking in air to cause its body to swell and to split the old exoskeleton open. When it does, the larva then breaks out with a new exoskeleton and physical features.
Larval Instars In Ants
With every molt, physical changes in the larvae manifest. In ants, these physical changes may include altered body proportions, color, hair growth, and changes in both head width and structure.
For instance, in a study published by the Entomological Society of Japan, researchers observed the harvester ant Messor aciculatus and found that it has 3 instars with each of the following distinguishing characteristics:
- Instar 1. Cranium width: 0.24-0.30mm; Very minute hairs on the head prothorax; mandibles with one acute medial toot; No recognizable spinules on the basal half of medial surface.
- Instar 2. Cranium width: 0.29-0.33mm; Short and sparse hairs on head and body; Mandibles with several spinules in addition to one medial tooth; Maxillary palp a rather wide frustum and galea a slender frustum.
- Instar 3. Cranium width: 0.33-0.37mm; Body hairs abundant on whole surface, Antenna with three sensilla; Mandibles small; One acute medial tooth; Basal half of medial surface with several long spinules; Maxillae lobose; Palps paxilliform; Galea digitiform.
In short, each instar for M. aciculatus could be distinguished through cranium width, the mandibles, and most significantly, distribution of body hairs.
Another study on the ant species Myrmelachista catharinae shows very similar results. The number of larval instars was estimated at 3 and each instar was characterized by the head capsule, mandibles, and the body.
Do Ants Go Through Complete Metamorphosis?
Yes, ants go through complete metamorphosis. Their immature forms look very different from their adult forms and their life cycle includes 4 stages: the egg, larva, pupa, and adult.
How Long Do Ants Live?
Ants can live for weeks or decades depending on the species and their status in the colony. Ants with episodic roles tend to live the shortest. Males for example only live for weeks and die shortly after they mate.
Workers on the other hand, live longer as they fulfill an important role for colony growth. That said, they don’t outlast queens which in some species may live up to decades.
Ants go through complete metamorphosis and molt multiple times during the larval stage of their development. They do so in order to continue growing as they go through the process of metamorphosis.
Should they fail to molt, then they’d most likely end up getting crushed by their hard exoskeletons and cease to develop into adult ants.