Polistes dominula (often misspelled as dominulus), sometimes referred to as the European paper wasp,^[1] is one of the more common and well-known species of social wasps in Europe. It is considered an invasive species in Canada and the United States.

Life cycle

Nests are begun by overwintered founding queens or foundresses, which spend about a month in the spring constructing a nest and provisioning offspring, the first of which will become daughter workers in the growing colony. Males are produced later, and when they start to appear, a few daughters may mate and leave their nest, to become foundresses the next season. The switch from production of workers to production of future foundresses (gynes) is not utterly abrupt, as has been considered the case for other species of Polistes.

The colony disperses in the late summer, with only males and future foundresses produced instead of workers, and individuals frequently cluster in groups (called a hibernaculum) to over-winter. Hibernation does not usually take place on former nest sites.

Polistes dominula female

Dominance hierarchy system

Paper wasp with regurgitated nectar

Morphologically, foundress and subordinate reproductive members of the colony differ little. However, several studies have shown behavioural differentiation occurs,^[2][3] with the role an individual female takes being determined by social interaction within the colony. Typically, the alpha female dominates all other individuals of a colony, and this female lays the majority of eggs, and partakes in differential oophagy. The alpha female devotes much of her time to social interaction, in comparison to subordinates that are much more involved in foraging and brood care.^[4]

These behavioural divisions are not permanent; if an alpha female is removed from a nest, then another female (usually the second-most dominant, beta female) assumes the role and behavioural profile of the removed dominant. Indeed, individuals alternate between different profiles of behaviour within their own dominance rank position.

Some studies seem to indicate the dominant female, through its behaviour, suppresses the ovarian development of subordinates.^[3] Abdominal wagging is thought to serve as a dominance signal between dominant foundresses and subordinates, but studies by Roseler and Roseler (1989) showed ovariectomised dominants failed to restrict subordinate reproduction whilst still retaining dominance.

Evidently, some factors present in the interactions of females on the nest can influence which daughters become workers and which become gynes; despite some minor physiological differences (primarily in the fat body), "gyne-destined" females produced late in the colony cycle can be induced to become workers if placed on nests that are at an earlier stage of colony development, and the converse is also true. This indicates a significant degree of flexibility in the caste system of this species.

Nest-mate recognition

Dominant individuals of P. dominula have differing cuticular profiles to workers,^[5] and the frequent observations of the dominant female stroking its gasters across the nest surface, combined with its staying on the nest for longer times than subordinates, suggests the dominant individual may contribute more to the nest odour.

Distribution

P. dominula on a lily plant

The native range of P. dominula covers much of southern Europe and North Africa, and temperate parts of Asia as far east as China.^[6] It has also been introduced to Australia, New Zealand and North and South America.

This species was introduced into the United States in 1968 in the New Jersey Pine Barrens and spread throughout most of the country during the 1980s and 90s, in some cases partially replacing native species. Another introduction was discovered in the late 1970s in Cambridge, Newton and Somerville, Massachusetts. The first wave consisted of solitary-founding but socially-nesting individuals, then a wave of social founders (several females found a new nest together). In warmer regions, there have been reports of "supercolonizers" most of whom enlarge their natal nests in successive years, rather than dispersing.

In the United States, P. dominula nests earlier in the spring, in a wider variety of nest sites, and feeds on a larger variety of insects than native species, which feed almost exclusively on caterpillars.^{[citation needed]} Most entomologists consider it to be an invasive species. This wasp can be mistaken for a yellowjacket, as it is black strongly marked with yellow, in a pattern very reminiscent of a yellowjacket, and quite different from the native North American species of Polistes.

Nomenclature

P. dominula is frequently referred to as Polistes gallicus, which is a separate species. It was originally described in 1791 by Johann Ludwig Christ as Vespa dominula. The specific epithet dominula, is a noun meaning "little mistress",^[7] and following the International Code of Zoological Nomenclature, species epithets which are nouns do not change when a species is placed in a different genus. Authors unaware that dominula was a noun have misspelled the species name as dominulus for decades.

References

Further reading

• Karsai, I. & Penzes, Z. (1996). "Intra-specific variation in the comb structure of Polistes dominulus: parameters, maturation, nest size and cell arrangement". Insectes Sociaux 43 (3): 277–296. doi:10.1007/BF01242929.