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Robert's son, meanwhile, was trying to cope with adolescent confusion in the form of Claire, whom he met on the school bus. Claire had quite enough to cope with, what with her spots and the dreadful embarrassment of her mother Tessa's advancing pregnancy - and at her age, too! And as though this were not enough, she was having to put up with the child from her hell, her cousin Hugh, who had come to stay while his parents were abroad.
When Robert planned to hold a new-style Carol Service and Hugh decided to introduce a little realism into the Christmas story in the shape of Tessa's pet pig, the villagers began to wonder just what was in store for them. Genre: Literary Fiction. The two genera are estimated to have diversified in the early Oligocene. The most recent common ancestor of the extant species in the kallimoid clade node 9, Fig. The basal relationships of the kallimoid clade are poorly supported Wahlberg et al. However, regardless of topology, several major lineages diverged in early to mid-Eocene. The rogue taxa as termed by Wahlberg et al.
The three genera are monotypic and thus further sampling of extant species is not possible. It is clear that these taxa have had a long period of independent evolution, and whether they are remnants of once diverse clades is a matter of speculation. Victorinini node 8, Fig. The estimated times of divergence for the genus Anartia are much older than previously calculated Blum et al. The lineage leading to Junoniini node 7, Fig. There appear to have been two periods of divergences in Junoniini, once in the early to mid-Oligocene and a second time in the early Miocene Figs.
Genera in Kallimini have diverged in a steady stream every 7 to 10 My Figs.
The Australasian Doleschallia is the first to diverge in the mid to late Eocene, then the Asian Kallima in the early Oligocene, and finally the two African genera diverged in the early Miocene. The lineage leading to Melitaeini has also had a long period of independent evolution about 10 My before the current subtribes diverged in the late Eocene and the early Oligocene Figs. The subtribes Melitaeina, Phyciodina, and the as yet formally unnamed Chlosyne -group and Gnathotriche -group see Wahlberg et al.
It appears that the unresolved relationships are due to few informative characters rather than character conflict. The subtribes Melitaeina and Phyciodina have diversified during the Miocene. As in all model-based work, it is of utmost importance to investigate the robustness of one's results to varying parameter values. In this study I have particularly investigated the effect of varying priors in a Bayesian relaxed clock analysis. I have found that for the current data set and associated fossil calibration points, the parameter that affects the results the most is the rate of molecular evolution from the ingroup node.
Priors for this parameter which were tested varied threefold and results from the fastest two priors were more similar to each other than to the slowest prior tested Table 1. This is mainly due to there being no constraint on the age of the root node, allowing the estimated age of the root to stretch further back in time when a slow prior of rate of molecular evolution is invoked in this case 0. In contrast, in this study the fossil constraints do not allow the age of the root to come too much forward in time and thus priors that invoke a molecular rate of evolution that is too fast in this case 0.
The results are not very sensitive to the other priors used, such as the variation in the rate of evolution, age of the root node, or the phylogenetic hypothesis. The effects of polytomies on results of divergence time analyses have not been investigated in detail as yet. The estimates of times of divergence are heavily dependent on the fossil constraints imposed and thus a critical look at the position of the constraints on the phylogenetic hypotheses is needed.
However, according to Wahlberg et al. Thus it is justified to assume that the fossil Vanessa represents a species that is sister to the extant Vanessa species. The two other fossils were used to constrain the age of Hypanartia. Both of these are from the Florissant formation in Colorado. Extant Hypanartia are restricted to tropical areas, mainly in South America, with one species reaching the southern border of the United States and three additional species occurring in Mexico.
The sister group of Hypanartia is still not clear as shown in this study , and therefore the distribution of the ancestor of the genus is not clear also shown in Wahlberg et al. The fossils of Prodryas and Lithopsyche do show that an ancestral species of Hypanartia was present in North America some 34 Mya. In either case, it does appear justified to use the fossils to constrain the maximum age of the genus Hypanartia.
Evidently the major evolutionary events in Nymphalinae have happened during the Tertiary Figs. Based on fossil evidence, the Tertiary was a period of intense diversification, especially in herbivorous insects Rasnitsyn and Quicke, In Nymphalinae, diversification of lineages has happened during the Eocene, Oligocene, and especially the Miocene at the species level , in line with the observations of Labandeira et al. Geologically, the Tertiary is characterized by the final breakup of remnant Gondwana 52 to 30 Mya , the docking of the Indian subcontinent to the Asian continent and subsequent rise of the Himalayas 50 Mya , the connecting of Africa with Europe 60 Mya , the connecting of Africa with Asia 21 Mya , and the connecting of North America with South America 3 Mya Scotese et al.
There also appears to have been an island arc allowing faunistic movements between North America and South America briefly 35 to 33 Mya Iturralde-Vinent and MacPhee, These geological events have had an effect on the historical biogeography of Nymphalinae. The historical biogeography of Nymphalinae was investigated by Wahlberg et al. The most recent common ancestor of Nymphalinae was inferred to have been widespread, although for several clades single continents were found to have been important for the diversification of the subfamily.
The ancestral distribution of the tribe Nymphalini was inferred to have been South America, whereas Africa was found to have played an important role in the diversification of the kallimoid clade. The dispersal-vicariance analyses of Wahlberg et al. The age of Nymphalinae suggests that the primary breakup of Gondwana i.
This is a particularly important observation, as many of the basal divergences in the clade lead to lineages that are predominantly South American e. Because the splitting of Africa from Gondwana happened earlier than the estimated age of the basal divergences, the presence of these lineages on the two continents must be the result of dispersal events between South America and Africa.
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Which of the two continents was the origin of the dispersalists might be inferred from the distribution of the sister group of Nymphalinae. Of the possible sister groups Wahlberg et al. Thus, South America is a likely candidate for the ancestral home of Nymphalinae. The distribution of the most recent common ancestor of Nymphalinae becomes even more interesting when looking at the Bayesian topology Figs. The topology and ages of divergences suggest that ancestors of Nymphalinae genera were widespread in remnant Gondwana South America, Antarctica, and Australia in the Paleocene and Eocene.
These ancestors have subsequently evolved into present day Smyrna, Colobura, Tigridia, Hypanartia , Victorinini, Mynes, and Doleschallia the latter two genera being largely restricted to tropical Australasia. There are no known geological events that may have helped the movements of butterflies from South America to Africa some 50 to 40 Mya, and so the colonizations would have been the result of long-distance dispersal events. In Junoniini the direction of colonization appears to have been from Africa to Asia, whereas in Kallimini it is the opposite.
All these butterflies are tropical and do not occur in temperate areas. The biogeography and estimated ages of divergence in the tribe Melitaeini provide some of the strongest evidence for the accuracy of the analyses presented here. Although the place of origin of the lineage leading to Melitaeini is not clear, the most recent common ancestor of the tribe was evidently present in North America Wahlberg and Zimmermann, ; Wahlberg et al.
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South America was colonized at least twice from North America, once in the Chlosyne -group and once by the ancestor of Phyciodina and the Gnathotriche -group. The main area of distribution of the Chlosyne -group is North America and tropical Central America, and there are very few species that make it into South America Wahlberg and Zimmermann, ; Wahlberg et al.
It seems clear that South America was colonized recently by species of the Chlosyne -group, perhaps in the past 3 My, after the formation of the Panamanian isthmus. This coincides precisely with a geologically short period of time when there apparently was a connection between North and South America through a peninsula or series of islands with short gaps between them stretching from northern South America almost to the Yucatan peninsula in Central America known as GAARlandia; Iturralde-Vinent and MacPhee, Thus it would appear that the ancestral species colonized South America and then diversified into the high-altitude Andean Gnathotriche -group with 4 species and the lower altitude Phyciodina.
Hypanartia is made up of two distinct clades, one of which is entirely restricted to Andean regions of northern South America and the other is more widespread in lowlands of South America, Central America, and most importantly with an endemic species on the Greater Antilles Willmott et al. The Caribbean species is sister to the rest of the species in the latter clade. The fossils in North America and the estimated age of divergence of the two clades coincides with the possible existence of GAARlandia, although the direction of colonization is not clear.
According to the Bayesian topology Fig. According to the parsimony topology Fig.
The Awkward Age by Francesca Segal | badufyjuhi.cf: Books
The possible fossil larva of Smyrna from Dominican amber Hammond and Poinar, suggests that Smyrna was present in the Greater Antilles, although it does not occur there currently. Two species of Anartia , not sampled by Wahlberg et al. These two species are sister to each other and are the sister group to the other three species of Anartia Blum et al. Given that the age of the three Anartia species sampled in my study is much older than thought, with the split between A. Clearly the study of the historical biogeography of Nymphalinae will benefit from species-level phylogenies.
Such phylogenies will give us more understanding of the biogeography of the ancestral species, which will in turn help us refine our estimates of divergence times in these butterflies. Vane-Wright, personal communication , and that future studies would help us get more insight into how long butterflies have existed.
The results presented here cast some light on the age of butterflies, if only indirectly. If this is truly so, the age of the family Nymphalidae must be substantially older than the 70 My proposed as the age of all butterflies Vane-Wright, Other lineages may also have survived, but we have no fossil evidence of such extinct lineages. To test this hypothesis, one would have to investigate whether diversifications of the other subfamilies happened at the same relative time as the diversification of Nymphalinae. Further studies on other clades in butterflies will corroborate or reject this hypothesis.
Both of the papilionid studies suggest that the age of butterflies as a whole is much older than 70 My, which is also suggested by my study and the study on Pieridae by Braby et al. It is obvious that only a thorough study of the butterfly clade would help clear up its age. This work has been supported by grant number from the Swedish Research Council. Oxford University Press is a department of the University of Oxford. It furthers the University's objective of excellence in research, scholarship, and education by publishing worldwide. Sign In or Create an Account.
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That Awkward Age Synopsis
Volume Article Contents. Material and Methods. E-mail: niklas.
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Cite Citation. Permissions Icon Permissions. Abstract The study of the historical biogeography of butterflies has been hampered by a lack of well-resolved phylogenies and a good estimate of the temporal span over which butterflies have evolved. Bayesian relaxed clock , Lepidoptera , Nymphalidae , tertiary , timing divergences. View large Download slide.
Table 1. View Large. Table 2. Table 3. Search ADS. A molecular phylogeny of the neotropical butterfly genus Anartia Lepidoptera: Nymphalidae. Google Preview. When and where did troidine butterflies Lepidoptera: Papilionidae evolve? Phylogenetic and biogeographic evidence suggests an origin in remnant Gondwana in the Late Cretaceous.
Molecular phylogeny and systematics of the Pieridae Lepidoptera: Papilionoidea : Higher classification and biogeography. Phylogenetic relationships among the Nymphalidae Lepidoptera , inferred from partial sequences of the wingless gene. Butterflies from the middle Eocene: The earliest occurrence of fossil Papilionidae. Florissant butterflies: A guide to the fossil and present-day species of Central Colorado. Phylogeny of the Araschnia butterflies Lepidoptera: Nymphalidae and evolution of seasonal polyphenism.
Reading the entrails of chickens: Molecular timescales of evolution and the illusion of precision. Extinction and biogeography in the Caribbean: new evidence from a fossil riodinid butterfly in Dominican amber. A larval brush-footed butterfly Lepidoptera: Nymphalidae in Dominican amber, with a summary of fossil Nymphalidae. Dating nodes on molecular phylogenies: A critique of molecular biogeography. Paleogeography of the Caribbean region: Implications for Cenozoic biogeography. Performance of a divergence time estimation method under a probabilistic model of rate evolution. Phylogenetic studies of the Melitaeini Lepidoptera: Nymphalidae: Nymphalinae and a revision of the genus Chlosyne Butler.
Dating lineages: Molecular and paleontological approaches to the temporal framework of clades. The breakup history of Gondwana and its impact on pre-Cenozoic floristic provincialism. Tertiary nymphalid butterflies and some phylogenetic aspects of systematic lepidopterology. Phylogeny of Polygonia, Nymphalis and related butterflies Lepidoptera: Nymphalidae : A total-evidence analysis. Dispersal-vicariance analysis: A new approach to the quantification of historical biogeography.
A nonparametric approach to estimating divergence times in the absence of rate constancy. Estimating absolute rates of molecular evolution and divergence times: A penalized likelihood approach. Southern hemisphere biogeography inferred by event-based models: Plant versus animal patterns. Plate tectonic reconstructions of the Cretaceous and Cenozoic ocean basins. Historical biogeography and the origins of the satyrine butterflies of the Tropical Andes Insecta: Lepidoptera, Rhopalocera.