The evolutionary significance of bimodal emergence in the butterfly, Maniola jurtina (Lepidoptera: Satyrinae) (L.).

Most temperate butterflies exhibit a tightly synchronized unimodal adult emergence to facilitate mate location. Exceptions are presumably subject to unusual selection pressure. This study examines the pattern of emergence in Maniola jurtina , which was found to exhibit both unimodal and bimodal emergence patterns at different sites in south-east England. The bimodal pattern was found on chalk grassland; elsewhere the emergence was unimodal. Adults from each emergence peak rarely meet, suggesting that there may be some degree of reproductive isolation. Morphological measurements and electrophoretic analysis of allozyme frequencies are carried out to quantify differentiation between emergence peaks. Captive stock was reared to examine differences in the immature stages. Butterflies from each emergence differ significantly in most morphological variables measured, those from the second peak tending to be smaller. The immature stages differ in morphology and longevity of the egg stage. Allozyme frequencies did not differ between peaks, suggesting that they are not reproductively isolated. Explanations for the maintenance of differences between emergence peaks despite gene flow are discussed. I propose that division of offspring between two emergence times may have evolved to avoid the risk inherent in placing all offspring in one peak which may be rendered inviable by temporal fluctuations in habitat quality.     

Spot distribution in the meadow brown butterfly, Maniola jurtina L. (Lepidoptera: Satyridae): South Welsh populations

Meadow brown butterflies, Maniola jurtina , were studied on Skokholm Island, off the Pembrokeshire coast, from 1976 to 1978 and at six other sites in south Wales from 1973 to 1977.
Daily survival of butterflies on Skokholm was estimated by capture-recapture data to be 0.70–0.84, but these values may be low because in the year of detailed study, 1976, dispersal rates between study sites were high and increased through the emergence period.
The butterflies were scored for the number and placing of the hind wing spots (Ford, 1975). Female populations in the east of our study area resembled English populations for they were unimodal at 0 spots. Spotting increased westwards until on Skokholm and the adjacent mainland the females caught were roughly equally likely to have 0, 1 or 2 spots. The Skokholm male populations had many 3-spotted individuals and so the mode of 2 in the spot-frequency distribution was less clear cut that in English populations. The trends in south Wales therefore resemble those found along the Cornish peninsula and on the Isles of Scilly. We suggest the increasingly maritime climate and the fragmentation of habitat on the coastal fringes of the species range are factors which may selectively favour butterflies with high flying and dispersal ability. Brakefield (1983) has offered evidence that more highly spotted meadow browns indeed have such an ability.     

Non-random dispersal in the butterfly Maniola jurtina: implications for metapopulation models

The dispersal patterns of animals are important in metapopulation ecology because they affect the dynamics and survival of populations. Theoretical models assume random dispersal but little is known in practice about the dispersal behaviour of individual animals or the strategy by which dispersers locate distant habitat patches. In the present study, we released individual meadow brown butterflies (Maniola jurtina) in a non-habitat and investigated their ability to return to a suitable habitat. The results provided three reasons for supposing that meadow brown butterflies do not seek habitat by means of random flight. First, when released within the range of their normal dispersal distances, the butterflies orientated towards suitable habitat at a higher rate than expected at random. Second, when released at larger distances from their habitat, they used a non-random, systematic, search strategy in which they flew in loops around the release point and returned periodically to it. Third, butterflies returned to a familiar habitat patch rather than a non-familiar one when given a choice. If dispersers actively orientate towards or search systematically for distant habitat, this may be problematic for existing metapopulation models, including models of the evolution of dispersal rates in metapopulations.     

Spot-distribution in Maniola jurtina (Lepidoptera) on small islands in southern Sweden

The Meadow Brown Butterfly, Maniola jurtina L., which is polymorphic for spotting on hind wings, was studied for five years on four small (0.15–1.0 km²) islands off the south coast of Sweden. Samples of females and males were unimodal for 0 and 2 spots, respectively. Spot-distributions remained unaltered in 1973–1974 but changed significantly in 1975 only to be restored again in 1976 and 1977. The change in 1975 was assumed to be associated with an unusually dry and warm summer and the results are discussed in terms of natural selection.     

Phylogeography and counter-intuitive inferences in island biogeography: evidence from morphometric markers in the mobile butterfly Maniola jurtina (Linnaeus) (Lepidoptera, Nymphalidae)

Distribution of mobile organisms on near-continent islands is mainly shaped by factors operating over ecological rather geological time. However, the phylogeography of single species has the potential to expose historical factors at work. In the present study, West Mediterranean populations of the butterfly Maniola jurtina are studied using geometric morphometrics. The distribution of the two well established lineages ( Maniola jurtina jurtina in the Atlanto–Mediterranean area and Maniola jurtina janira in the Central–Eastern-Mediterranean area) on 12 islands and the adjoining continents are compared. The south-western lineage unexpectedly occurs on islands close to shores occupied by the eastern lineage. We have modelled the distribution of the lineages using three different hypotheses: (1) a contemporary isolation model, which predicts lineage occupancy of islands is linked to relative distances from neighbouring continental areas; (2) a refugial hypothesis, which predicts one lineage to be the ancestral one for the whole region studied, and then successively replaced over part of it; (3) a changing geography hypothesis, which predicts the two lineages to have evolved in their currently occupied areas, continuously sourcing islands subsequent to the Würm maximum glaciation. Of the three models, the refugial hypothesis is most highly correlated with the observed pattern, suggesting that Mediterranean islands may function as refugia during cold periods, much as the three mainland peninsulas of Iberia, Italy and Greece are known to have done. Thereafter, hybridization on the nearest and smallest islands has occurred, with the entire process supporting the notion of the joint influence of factors in ecological and geological time.  © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 98 , 677–692.     

Interpopulation variation and selective predation in the meadow brown butterfly, Maniola jurtina (L.) (Lepidoptera: Satyridae) in the Canary Islands

Samples of the meadow brown butterfly, Maniola jurtina , were collected from all five of the Canary Islands where it occurs. The butterflies were scored for several spotting characters on both fore- and hindwings and assessed for damage from predators.
The analysis reveals considerable interisland heterogeneity for spotting characters and suggests that the populations fall into two relatively distinct, homogeneous groups, which inhabit the islands of Gran Canaria and La Gomera, on the one hand, and Tenerife, El Hierro and La Palma, on the other.
The main predators are lizards and insectivorous birds. Predator damage is non-random in the following respects: males are more damaged than females; high spot male phenotypes are more damaged than low ones early in the flight period (April-May); symmetrical damage, probably acquired while resting, is commoner in females, while asymmetrical damage is more characteristic of males. Damage generally increases in both sexes through the flight period.
Comparison of the bulked Canary Island samples with museum material from North Africa and Iberia suggests that the former area is the more likely source of the island populations. However, samples from two islands more resemble Iberian stock and it is suggested that the butterfly may have colonized the islands, either by introduction or immigration, on two occasions.     

Does bird predation influence the spot-number variation in Maniola jurtina (Lepidoptera)?

For six years samples of the satyrine butterfly Maniolajurtina L. were collected on small islands in southern Sweden and scored for beak marks, i.e. damage on wings presumably resulting from attacks by birds; in the present study area mainly Red-backed Shrike Lanius collurio L. An overall mean of 8% (5–1496 in different years) of the females and 1396 (10–2296) of the males had beak marks. Both sexes of M. jurtina show variation in spot-number on the hindwings and there is some evidence that in some years the frequencies of different spot-number phenotypes with beak marks differ significantly from randomness. Although it is not known how beak mark frequencies are related to predation pressure (reflecting rates of predation or escapes?) it is suggested that, due to behavioural differences of spot-number phenotypes, birds act as a selective factor influencing the spot-number variation. The results are discussed in relation to a recent model proposed by Brakefield attempting to account for variation in spot-number in M. jurtina.     

Geographical variability in, and temperature effects on, the phenology of Maniola jurtina and Pyronia tithonus (Lepidoptera, Satyrinae) in England and Wales

ABSTRACT. 1. Geographical variability in, and temperature effects on, the mean date of adult flight period and the SD about this date are analysed for two univoltine, grassland butterflies in England and Wales from 1976 to 1985. Data were collected on the Butterfly Monitoring Scheme for Maniola jurtina (L.) at twenty-nine sites and Pyronia tithonus (L.) at twenty sites.
2. Substantial variability for mean date and SD occurs between years and between sites. Changes in mean date between years tend to occur consistently at different sites. The species show some parallel in variation between sites, especially for mean date.
3. June maximum temperature accounts for 95% and 75% of the variation in mean date between years in M. jurtina and P. tithonus , respectively ( r =-0.97 and -0.87). Similar relationships occur for temperatures cumulated over the period of post-winter development from March to July or August.
4. Greater geographical variability in phenology, and a generally less synchronized flight period in M.jurtina may be associated with broader habitat preferences than in P. tithonus.
5. The mean date of adult flight period remains at roughly the same date at more northerly latitudes. In M.jurtina the flight period becomes more synchronized, begins later and ends earlier in the north. P. tithonus shows little or no indication of such a response to latitude. This is discussed with regard to changes in season length and factors limiting the species'range.     

Is the last glaciation the only relevant event for the present genetic population structure of the meadow brown butterfly Maniola jurtina (Lepidoptera: Nymphalidae)?

Phylogeographical studies are available for a considerable number of European species, but few analyses exist for temperate species with very large and fairly continuous populations that are also absent from Northern Europe. Therefore, we studied the butterfly Maniola jurtina as a model for this group. The species has two major genetic lineages (mean genetic distance between lineages: 0.033; F _CT: 0.052), most probably evolving in glacial differentiation centres in the western and eastern Mediterranean. The onset of this differentiation might have been the beginning of the last glacial stage maximum some 40 kyr bp . A hybrid zone between these two lineages exists in western Central Europe. No genetic substructures have been found within the two lineages ( F _SC: 0.017) and average genetic distances are very small. Therefore, it is highly probable that postglacial expansion was of the phalanx type. There is, at most, very limited differentiation at regional and local scales. However, the genetic diversity within populations is high (means: A : 2.68; H _E: 17.2%; P : 78%), as would be predicted for such a common species. Comparison of these results with a published allozyme analysis revealed a similar phylogeographical pattern, but lower genetic diversity in the latter. Morphological patterns of wings and genitalia show similar geographical patterns as allozyme data.   © 2005 The Linnean Society of London, Biological Journal of the Linnean Society , 2005, 85 , 419–431.     

The biogeography of the western Mediterranean: elucidating contradictory distribution patterns of differentiation in Maniola jurtina (Lepidoptera: Nymphalidae)

In the western Palaearctic, the Mediterranean zone is an important region where taxa and genes of thermophilous organisms are preserved during glacial stages and new clades are generated. This is achieved through the existence of refugia over Mediterranean Europe and North Africa, where organisms persisted and continued to evolve during the cold phases. However, it is not clear in detail how these refugia function for the maintenance of ancestral taxa, the evolution of new taxa, and as launching pads during postglacial colonizations of northern Europe. One outstanding issue is the incongruence of findings from different marker systems. For the butterfly Maniola jurtina, morphometry and allozyme data analyzed for populations scattered over Europe and North Africa show congruent patterns for Sicily and the Maghreb but produce discrepant results for the Italian mainland. This discrepancy between allozyme and morphological data can be explained by recent gene flow in the wake of postglacial range expansions and shifts. It is evident that colonization histories are far more complex than originally considered. We highlight different aspects of colonization and evolutionary history emerging from the joint use of different marker systems and advocate multiple uses of different markers in paleobiogeographic reconstructions to explore evolutionary events and colonization pathways. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 103 , 571–577.     

Fifteen new polymorphic microsatellite loci for the meadow brown butterfly,Maniola jurtina

We characterized fifteen microsatellite markers for the butterfly Maniola jurtina. For the six studied populations (96 samples) the total number of alleles per locus ranged from 3 to 55 and mean overall expected heterozygosity across all loci was 0.74. In spite of a high frequency of null alleles detected in part of the loci, a recurrent phenomenon in Lepidopteron, the estimation of pairwise F_ST seems rather insensitive to the presence of these null alleles as shown by the high correlation between F_ST calculated after correction for the presence of null alleles and non-corrected F_ST, indicating that the loci may be usable in population genetics, more specifically for the study of populations genetics structure.     

Spot variation in Maniola jurtina (L.) (Lepidoptera: Satyridae) in southern Portugal and a comparison with the Canary Islands

A sample of 2013 meadow brown butterflies, Maniola jurtina , was obtained in the Algarve, southern Portugal, on behalf of E.B. Ford, the founder of ecological genetics. Variation in the meadow brown occupied Ford's attention for more than 40 years. Ford died in 1988; most of his collection had earlier been destroyed, but the meadow browns remained and became available for analysis. The butterflies were scored for spotting characters on both fore- and hindwings. The population is homogeneous over the entire area of the Algarve and there is no conclusive evidence of a difference between the two years of collection (1986 and 1987). It is probably also homogeneous with southern Iberia in general, an area unique in the western Palaearctic range of the species as it is characterized by a high spot average in males and a low spot average in females. Algarve butterflies differ markedly from those of the Canary Islands, where there is considerable inter-island heterogeneity, supporting the view that the Canary Island populations did not originate from southern Iberia. In the Algarve, many females aestivate and by September there is an essentially all-female population. These are low-spotted and differ significantly from females active in May and June at the start of the annual (one generation) flight season.     

Biogeographic history of the butterfly subtribe Euptychiina (Lepidoptera,Nymphalidae, Satyrinae)

Peña, C., Nylin, S., Freitas, A. V. L. & Wahlberg, N. (2010). Biogeographic history of the butterfly subtribe Euptychiina (Lepidoptera, Nymphalidae, Satyrinae).—Zoologica Scripta, 39, 243–258. The diverse butterfly subtribe Euptychiina was thought to be restricted to the Americas. However, there is mounting evidence for the Oriental Palaeonympha opalina being part of Euptychiina and thus a disjunct distribution between it (in eastern Asia) and its sister taxon (in eastern North America). Such a disjunct distribution in both eastern Asia and eastern North America has never been reported for any butterfly taxon. We used 4447 bp of DNA sequences from one mitochondrial gene and four nuclear genes for 102 Euptychiina taxa to obtain a phylogenetic hypothesis of the subtribe, estimate dates of origin and diversification for major clades and perform a biogeographic analysis. Euptychiina originated 31 Ma in South America. Early Euptychiina dispersed from North to South America via the temporary connection known as GAARlandia during Eocene–Oligocene times. The current disjunct distribution of the Oriental Palaeonympha opalina is the result of a northbound dispersal of a lineage from South America into eastern Asia via North America. The common ancestor of Palaeonympha and its sister taxon Megisto inhabited the continuous forest belt across North Asia and North America, which was connected by Beringia. The closure of this connection caused the split between Palaeonympha and Megisto around 13 Ma and the severe extinctions in western North America because of the climatic changes of the Late Miocene (from 13.5 Ma onwards) resulted in the classic ‘eastern Asia and eastern North America’ disjunct distribution.     

Immature stages of the butterfly Magneuptychia libye (L.) (Lepidoptera: Nymphalidae, Satyrinae)

The immature stages of the butterfly Magneuptychia libye (L.) are described, and their morphology is compared with other Neotropical Satyrinae.     

Dispersal mood revealed by shifts from routine to direct flights in the meadow brown butterfly Maniola jurtina

A comprehensive mechanistic approach to dispersal requires the translation of the whole mobility register of the target organism into movement rules that could subsequently be used to model its displacements. According to the optimality paradigm, this procedure implies a cost–benefit analysis of mobility patterns taking into account not only movements, but also their external context and the internal state of the moving individuals. Using this framework, we detected a ‘dispersal mood’ in some individuals of the meadow brown butterfly Maniola jurtina. These adopted a direct flight strategy, which was topologically different from the previously documented foray search strategy. Those individuals that used the direct flight strategy moved straighter as soon as they left the habitat and avoided heading back to their patch of origin, which is the best inter‐patch search strategy when dispersal risks and costs are high. The direct flight strategy was conditional to sex: females used it twice as much as males. We suggest that this sex bias was due to female investment in offspring, which is maximized by male avoidance and spatial bet hedging. Inter‐patch dispersal of gravid females is crucial for the persistence of M. jurtina populations in spatially and temporally unpredictable environments.     

Influence of previous residency and body mass in the territorial contests of the butterfly Hermeuptychia fallax (Lepidoptera: Satyrinae)

Although many studies have evaluated the possible rules used by males to settle territorial contests, few have simultaneously considered the possibility of mutual or self-assessment of fighting ability and the effect of prior residence on the chances of winning. Here, we experimentally investigated the influence of previous residency on the development and outcome of contests between males of the butterfly Hermeuptychia fallax. By comparing the frequency of resident victories in nonmanipulated disputes versus interactions in which both rivals were induced to behave as residents, we showed that prior residency may interact with body mass in contest resolution. In nonmanipulated disputes, resident males showed high winning probabilities, although they were similar to losers in body mass. However, when both males behaved as residents, the disputes were longer and were settled in favor of the heavier male. This indicates that, although residency is an important component of male willingness to fight, it is not the only factor influencing conflict resolution. Despite the correlation between body mass and territorial success, the weight of neither winners nor losers correlated with fighting duration. We conclude that residence asymmetry may sometimes conceal male traits important to contest resolution and that it may obscure the identification of the assessment strategy used in contests.     

Variation in number of copulations in Theclini butterfly females (Lycaenidae: Lepidoptera)

The number of spermatophores inseminated in the bursa copulatrix of females of 21 species of Theclini butterflies varied from 0 to 38, a maximum much larger than reported so far. The variation of spermatophore number observed was analyzed on a phylogenetic tree recently determined, together with variation of wing colors and male mating tactics. Monandrous species tended to be sexually dimorphic in wing color and associated with male territoriality.