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Predation
During larval stages, caterpillars feed on leguminous plants of the genus Crotalia. These plants contain a large amount of toxins, particularly pyrrolizidine alkaloids (PAs), which are found in high concentrations in the seeds. Ornate Moth caterpillars sequester these toxins and use them as a deterrent for predators. PAs render them unpalatable to many of their natural enemies like coccinelid beetles, green lacewings, insectivorous hemiptera and insectivorous bats. When caterpillars metamorphose into adult moths, they carry the alkaloids with them, and these continue to protect them during the adult stage. However, some predators are immune to the chemicals. These include loggerhead shrikes and other Ornate Moth larvae.

Since PAs are an extremely valuable resource, individual larvae compete with one another to colonize an entire pod containing PA-rich seeds. Larvae that are unable to take ownership of a pod must obtain them from leaves and they will sequester a smaller amount of PAs. As a result, they are more susceptible to predation. In addition, larvae that manage to dominate a pod develop much faster than larvae feeding on leaves. This is very important because having a shorter development time also leads to reduced predation and parasitism. Another benefit from feeding inside of pods is increased physical protection from predation.

Although it is beneficial to feed on seeds, larvae do not enter the pods immediately after they hatch. During the first larval instars, caterpillars feed on leaves and it is not until the second or third instar that they enter the pods. The evolutionary benefits of this strategy are not completely understood.

Cannibalism
It has been documented that on occasion Ornate Moth caterpillars cannibalize other eggs, pupae or larvae from the same species. Since PAs are a limited resource, some caterpillars often do not reach optimal levels and recur to cannibalism. This behavior is a consequence of PA deficiency rather than hunger, since deficits in alkaloids are the main cause of mortality. Pupae cannibalism is rare because larvae normally pupate far away from the plant where they feed. Egg cannibalism is also rare because eggs provide larvae with very small quantities of PA. and eggs from the same cluster hatch synchronously. Larvae may also feed on other larvae that are laden with alkaloids. This is more common since feeding on one single larva is sufficient to compensate for any alkaloid deficiency the cannibalistic caterpillar has. One interesting fact about cannibalism in the Ornate Moth larvae is that caterpillars do not have the ability to recognize other larvae pertaining to the same kin. Studies suggest that this is due to the fact that these larvae do not experience a strong selective pressure that would favor a mechanism for kin recognition.

Mating
Ornate Moths of both sexes use very complex reproductive strategies, making this species an excellent model system for studying sexual selection. Females mate multiply over their three to four week lifespan as adults. They mate with an average of 11 males, each of whom provides her with a nuptial gift: a spermatophore, containing sperm, nutrients, and alkaloids. Adult males invest up to 11% of their body mass to create the spermatophore they provide to a female during mating. The nutrients given in the spermatophore allow the female to produce, on average, an additional 32 eggs.

Copulation lasts for up to 12 hours. It takes the male about two hours to transfer the spermatophore containing all of the sperm and nutrients he is going to offer to the female. The remaining hours of copulation are exclusively used for alkaloid transfer. These alkaloids distribute themselves evenly around the female body, even the wings, and offer her great protection against predation. Eventually, the female allocates about one third of the alkaloids she receives to her ovaries, where they will be used to confer protection to the eggs.

Female pheromonal chorusing
Ornate Moth mating behavior is exceptional in that females compete with other females to obtain more males as opposed to males competing with males, which is what is commonly seen in most sexually-reproducing organisms. In order to attract males, females release sexual pheromones that males can detect over long distances. They normally begin their sexual advertisement at dusk and continue for several hours. In most moth species, females do not interact with one another during pheromone release. Female Ornate Moths are unique in that females from the same family often engage in collective pheromone release termed “female pheromonal chorusing”.

This phenomenon arises from competition among female Ornate Moths, which is a consequence of a female-biased operational sex ratio. This means that at any given time there are more females than males seeking to copulate. The reason behind this ratio is the fact that after copulating, males lose up to 11% of the mass so they need to take the time to sequester resources to be able to deliver a spermatophore to the next female they mate with. Contrary to males, females do not need time to prepare to the next copulation. Due to unequal mating rates, males become valuable for females and female-to-female competition is very high. Engaging in pheromonal chorusing allows females to increase the attractiveness of genetic relatives and increase their indirect fitness. Females may also, but less frequently, engage in female chorusing with unrelated females. It has been suggested that chorusing is still beneficial then, because cooperation for pheromone release may increase the attractiveness of the entire group and increase each moth’s individual fitness. It has been experimentally shown that when females detect other female pheromones they increase the rate of pheromone release and call for longer periods of time. Such observations support the hypothesis that females cooperate with one another to increase mating success.

Postcopulatory sexual selection
After copulating with several males, rival sperm carried by a female do not compete in numbers for access to the eggs. Females direct a postcopulatory selective process where they choose male sperm based on the intensity of a courtship pheromone that was released prior to copulation, hydroxydanaidal (HD). The intensity of this signal is directly proportional to the amount of alkaloids sequestered by the moth during the larval stages. As a consequence, this pheromone is an indirect indicator of success during larval development. It is thought that females use it to assess the genetic qualities of the male, which will be passed on to the offspring. Females exclude sperm pertaining to the males with lower HD signals. The female reproductive system consists of many chambers and conducts that are surrounded by muscles. Females use this musculature to channel their selected sperm, normally pertaining to a single male, to their eggs.