Sociobiology 62(1): 88-91 (March, 2015) DOI: 10.13102/Sociobiology.V62i1.88-91
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View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Portal de Periódicos Eletrônicos da Universidade Estadual de Feira de Santana (UEFS) Sociobiology 62(1): 88-91 (March, 2015) DOI: 10.13102/sociobiology.v62i1.88-91 Sociobiology An international journal on social insects RESEARCH ARTICLE - WASPS Ambient Temperature Influences Geographic Changes in Nest and Colony Size of Polistes chinensis antennalis Pérez (Hymenoptera: Vespidae) S Hozumi1, K Kudô2, H Katakura3, S Yamane4 1 - Chigakukan secondary school, Mito 310-0914, Japan 2 - Niigata University, Niigata 950–2181, Japan 3 - Hokkaido University, Sapporo 060–0810, Japan 4 - Ibaraki University, Mito 310-8511, Japan Article History Abstract In some Polistes wasps, the foundresses build huge nests during the founding phase to Edited by improve the thermal condition of these nests. This implies that Polistes wasps change their Fernando Barbosa Noll, UNESP, Brazil Received 07 March 2014 nesting manner in relation to ambient temperature. To test the hypothesis that nest size Initial acceptance 16 May 2014 increases with latitude, colonies of Polistes chinensis were collected from 11 locations. Final acceptance 13 September 2014 Three nest parameters, the number of cells cell length and index of functional envelope, increased with latitude. The number of cells at the northernmost station was 60, which Keywords was 1.5 times more than in lower latitudes. Cell length increased by approximately 4 mm Paper wasp, Polistes chinensis, geographic from low to high latitudes, indicating that extra-building in P. chinensis is remarkable in variation, nest architecture. adding new cells. The number of first broods was not correlated with latitude, whereas Corresponding author the number of second brood increased with latitude because of the numerous cells built Satoshi Hozumi at high latitudes. Chigakukan secondary school Mito 310-0914, Japan E-Mail: [email protected] Introduction colony production and produce as many reproductive gynes as possible (reproduction period). The wasps build an exposed comb, Climate is a major physical factor that determines the in which the construction of new cells and elongation of cells are geological distributions and life histories of organisms. Some commonly related to oviposition and the development of larvae, climates generate different ecological traits among populations of respectively (Delaeurance’s law; Delaeurance, 1957). However, the same species (e.g., Angilletta, 2009). Assessing adaptations species in different climates exhibit different nest-building activities to different climatic regimes helps us to understand the and colony cycles. Yamane (1972) showed that P. chinensis major selective pressures affecting organisms and to predict foundresses that inhabit the cool northern areas of Japan (nesting their reactions to global and local climatic changes in the duration 3.5–4 months) build many empty cells just before the environment (Chown, 2001). emergence of the first adults and elongate the cells beyond the In social insects, ambient temperature is an important lengths of the pupae. In contrast, in the warm areas of Japan, P. physical factor that greatly affects insect activity (Heinrich, 1993). chinensis nesting activity is consistent with Delaeurance’s law, Differences in local ambient temperatures lead to differences in and the nesting duration is approximately 6 months. nesting activities (Fucini et al., 2014), rate of development of A few previous studies have focused on the intra-specific immature stages (Miyano, 1981), and duration of nesting periods changes in nest size, in relation to nest thermoregulation; i.e., (Yamane, 1969), and intra-specific changes have been reported in adaptation to low temperature. Yamane & Kawamichi (1975) the genus Polistes (Hymenoptera, Vespidae). Polistes paper wasps found that P. chinensis foundresses build larger nests in are independent-founding social wasps. A lone foundress builds higher latitudinal regions and concluded that numerous and an exposed nest and nurses the first brood of larvae until worker long cells function as air chambers that improve thermal individuals emerge (pre-emergence period; Reeve, 1991). After conditions in the brood-rearing area of the nest, similar to the eclosion (post-emergence period), the adult individuals increase envelope of a vespine nest (functional envelope). This means Open access journal: http://periodicos.uefs.br/ojs/index.php/sociobiology ISSN: 0361-6525 Sociobiology 62(1): 88-91 (March, 2015) 89 that foundresses build more cells for nest thermoregulation to accelerate the development of the first batch of larvae (first brood) during the pre-emergence period. However, the observations were performed in only 2 locations, and thus further study is needed to understand the relationships between climate and the geographic variation in nest size. In this study, we set 2 goals. The first was to verify whether nest sizes increase geographically from low to high latitudes as Yamane and Kawamichi (1975) predicted. If P. chinensis foundresses change their nesting behavior according to ambient temperature, the number and the length of cells should increase with latitude. We collected P. chinensis nests at 11 locations across Japan islands and examined the relationship between nest size and latitude. The second goal was to clarify the relationship between latitude and colony productivity. If foundresses invest more resources in nest building in higher latitudinal regions, the numbers of individuals in the first and second broods would be expected to decrease as a tradeoff. We investigated the numbers of individuals in first broods at 6 locations along a latitudinal gradient and calculated an index of functional envelope. In this study, we also discuss the difference in nesting behavior between lower and higher latitudinal areas. Fig 1. Localities where nests of P. chinensis were collected. Material and Methods Colony composition Nest parameters Colony composition was investigated at 6 locations (St4, St7, St8, St9, St10, and St11) to determine latitudinal differences In order to determine the latitudinal differences in nest among colonies. The content of each cell (egg, young larva, old size among the islands of Japan, a total of 168 nests of P. larva, pupa, or empty) was recorded for all nests immediately chinensis antennalis were collected at the 11 locations shown after nest collection. For this study, 1st to 3rd instar larvae were in Table 1 and Fig. 1. Two nest parameters, the number of classified as young larvae, and 4th and 5th instar larvae were cells and cell length, were measured for each nest. The classified as old larvae. measurement was performed as follows: number of cells, total To examine the hypothesis of Yamane and Kawamichi number of cells was counted for each nest; cell length (mm), (1975), we defined the index of functional envelope (IFE) to be maximum value of the longest cell was measured for each the nest volume per first brood, i.e., the entire nest volume per nest with a vernier calliper to the nearest 0.1 mm. total number of individuals in the first brood. Nest volume (ml) Table 1. Geographic positions and altitudes of localities where Polistes chinesis nests were collected. Station Locality Latitude Longitude Mean annual Date collected Collector temperature (˚C) St1 Fukuoka 33°34’N 130°23’E 17.0 19-21 May 2000 N. Kumano St2 Tsu 34°43’N 136°30’E 15.9 4-5 June 1997 K. Kudô St3 Toki 35˚21’N 137°11’E 15.8 7-8 June 1997 K. Kudô St4 Itako 35°56’N 140°34’E 14.5 9-10 June 1998, 10 June 1999 S. Hozumi St5 Tsurugi 36°27’N 136°37’E 14.3 16-17 June 1997 K. Kudô St6 Kanazawa 36°33’N 136°39’E 14.6 19 June and 7-8 July 1997 K. Kudô St7 Tanagura 37°01’N 140°22’E 11.5 8 June 1999 S. Hozumi St8 Mizusawa 39°08’N 141°08’E 10.7 8 June 1998, 19 June 1999 S. Hozumi St9 Shichinohe 40°41’N 141°08’E 10.4 4 July 1998, 3 July 1999 S. Hozumi St10 Kanagi 40°54’N 140°27’E 10.3 4 July 1998, 3 July 1999 S. Hozumi St11 Okushiri 42°08’N 139°29’E 9.7 21 July 1999, 18 July 2000 S. Hozumi 90 S Hozumi, K Kudô, H Katakura, S Yamane - Geographic Changes in Nest and Colony Size of Polistes chinensis was estimated as follows: all of the cells were filled with small granular glass beads (diameter 0.1 mm), and the volume of beads 0.05 0.05 was measured with a graduated cylinder to the nearest 0.1 ml (see 0.005 <0.05 =0.1381 p< p p< p< Yamane et al., 1998). This measurement was repeated 3 times, p Significance and the values were averaged. correlation Statistics rank Spearman’s ρ 1.000 0.8407 0.8986 0.9428 Spearman’s rank correlation analysis was used to quantify -0.6789 the relationship between nest and colonial parameters and latitude. All analyses were performed with EZR ver. 1.22 (Kanda, 2013) =24 (8.5) N St11 (14.0) (40.0) (10.0) (0.68) on a personal computer. 9.4 ± 6.1 8.7 ± 1.5 12.4 ± 4.7 38.5 ± 13.8 0.84 ± 0.42 Results =13 St10 (8.0) (7.2) N Nest size variation (12.0) (22.0) (0.58) 9.1 ± 6.8 7.2 ± 0.4 12.6 ± 2.3 23.1 ± 8.8 0.59 ± 0.10 colonies. Index of functional envelope (IFE) was calculated Table 2 shows the geographical variation in the number and length of cells. Both parameters significantly increased =18 St9 (6.0) (7.2) N with latitude (Spearman’s rank correlation: number of cells, (15.0) (23.5) (0.50) 4.6 ± 3.7 7.2 ± 1.1 14.2 ± 5.1 23.3 ± 7.0 ρ = 0.6272, p < 0.05; cell length, ρ = 0.7671, p < 0.01).