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Phylogeographic Investigations of the Widespread, Arid-Adapted Antlion Brachynemurus sackeni Hagen (Neuroptera: Myrmeleontidae)  [PDF]
Joseph S. Wilson,Kevin A. Williams,Clayton F. Gunnell,James P. Pitts
Psyche , 2010, DOI: 10.1155/2010/804709
Abstract: Several recent studies investigating patterns of diversification in widespread desert-adapted vertebrates have associated major periods of genetic differentiation to late Neogene mountain-building events; yet few projects have addressed these patterns in widespread invertebrates. We examine phylogeographic patterns in the widespread antlion species Brachynemurus sackeni Hagen (Neuroptera: Myrmeleontidae) using a region of the mitochondrial gene cytochrome oxidase I (COI). We then use a molecular clock to estimate divergence dates for the major lineages. Our analyses resulted in a phylogeny that shows two distinct lineages, both of which are likely distinct species. This reveals the first cryptic species-complex in Myrmeleontidae. The genetic split between lineages dates to about 3.8–4.7 million years ago and may be associated with Neogene mountain building. The phylogeographic pattern does not match patterns found in other taxa. Future analyses within this species-complex may uncover a unique evolutionary history in this group. 1. Introduction Phylogeographic analyses investigate the relationship between genealogies and their geographic distribution [1]. Many recent studies have investigated the historical biogeography of the Nearctic arid lands through the phylogeographic analyses of wide-ranging, desert-adapted taxa [2–7]. These studies often associated major genetic divergences with mountain-building events that took place in the late Neogene. As a result of these late Neogene events, deeply divergent clades were found to be restricted to the eastern (Chihuahuan) and western (Mojave and Sonoran) deserts. While the various hypotheses detailing the causes of the diversification of the Nearctic’s arid-adapted biota approach a generalized model [8], little work has been done on wide-ranging, arid-adapted arthropods [7]. Phylogeographic analyses of these organisms will aid in the development of a generalized model detailing diversification in the deserts. In addition to the importance of phylogeographic analyses to historical biogeography, these analyses often uncover the existence of cryptic species [9–13]. Recognition of these complexes is an essential aspect of documenting biodiversity and can be beneficial in the development of conservation strategies [14, 15]. While some phylogeographic investigations have been done on arid-adapted arthropods, like beetles [16, 17], velvet ants [7, 18], and spiders [2, 19], several diverse arthropod groups remain unexplored. One such group are the antlions (Neuroptera: Myrmeleontidae). Antlions in the tribe
The Invertebrate Life of New Zealand: A Phylogeographic Approach  [PDF]
Steven A. Trewick,Graham P. Wallis,Mary Morgan-Richards
Insects , 2011, DOI: 10.3390/insects2030297
Abstract: Phylogeography contributes to our knowledge of regional biotas by integrating spatial and genetic information. In New Zealand, comprising two main islands and hundreds of smaller ones, phylogeography has transformed the way we view our biology and allowed comparison with other parts of the world. Here we review studies on New Zealand terrestrial and freshwater invertebrates. We find little evidence of congruence among studies of different taxa; instead there are signatures of partitioning in many different regions and expansion in different directions. A number of studies have revealed unusually high genetic distances within putative species, and in those where other data confirm this taxonomy, the revealed phylogeographic structure contrasts with northern hemisphere continental systems. Some taxa show a signature indicative of Pliocene tectonic events encompassing land extension and mountain building, whereas others are consistent with range expansion following the last glacial maximum (LGM) of the Pleistocene. There is some indication that montane taxa are more partitioned than lowland ones, but this observation is obscured by a broad range of patterns within the sample of lowland/forest taxa. We note that several geophysical processes make similar phylogeographic predictions for the same landscape, rendering confirmation of the drivers of partitioning difficult. Future multi-gene analyses where applied to testable alternative hypotheses may help resolve further the rich evolutionary history of New Zealand’s invertebrates.

Fu Zhi-jun,Gao Jun-li,

植物生态学报 , 1994,
Abstract: Betula albo-sinensis forest is an important type of forest vegetation of the Taibai Mountain region, distributed From 1950 to 2650m on the south slope and from 2200 to 2750m above sea level on the north slope.Using clustering analysis(UPGMA),twenty plots of Betula albo-sinensis forest were classified into seven types:i) B. albo-sinensi Quercus liaotung-ensis forest; ii) B. albo-sinensis Q.liaotungensis Pinus armandii forest;iii)B. albo-sinensis P. armandii forest; iv) B. albo-sincensis forest;v)B. albo-sinensis P armandii B. utilis fargesis forest;vi) B. albo-sinensis B. utilis Abies jargesii forest;vii) B albo- sinensis B. utilis forest.Seven types of B,albo- sinensis forests were regularly distributed in this order along the altitudinalgradient, but B. albo-sinensis forest always dominates and the forest structureis relatively stable.The analysis of the Bctula albo-sinensis population structure,dynamicsand natural regeneration indicated the Betula albo-sincntis forest was in a de-grading stage.Betula albo-sinensis forests are mature or over-mature at present,artificialregeneration should be strengthened.

MO Ming-He,CHI Sheng-Qi ZHANG Ke-Qin,

菌物学报 , 2001,
Abstract: Strains of Hirsutella sinensis Liu, Guo, Yu & Zeng were isolated from several fruits of Cordyceps sinensis (Berk.) Sacc. collected in Yunnan Deqin Bai Ma Snow Mountain by amended methods. The process of ascospores microcycle conidiation was illustrated and was taken as an evidence for determining our isolates as the anamorph of Cordyceps sinensis (Berk.) Sacc.

REN Jian-Yi,YUE Ming,REN Jian-Yi,LIN Yue,YUE Ming,

植物生态学报 , 2008,
Abstract: 红桦(Betula albo-sinensis)广布于我国太白山中高海拔地区,普遍存在着更新障碍。为了给红桦林的自然更新提供新的解释与证据,我们对2400粒红桦种子进行了去果皮观察并计数发芽率,观察了红桦种子在不同光合有效辐射(Photosynthetically active radiation,PAR)和不同光照时间(强光照:PAR为464.7μmol photons·m^-2·s^-1,12h·d^-1;中光照:PAR为233.8μmol photons·m^-2·s^-1,12h·d^-1;弱光照:PAR为233.8μmol photons·m^-2·s^-1,0.5h·d^-1)、不同昼夜温差(25/20℃、20/15℃、15/10℃)和去果皮处理下的发芽率,以及无光照处理下的发芽率。此外,还观察了种子在不同覆盖物(阔叶、针叶、针阔混合)和不同基质(土、沙)中以及在落叶(阔叶、针阔混合)中的发芽率。红桦种子成熟时,大约54.29%为饱满具活力的种子。种子在25/20℃的昼夜温差下发芽率最高,而在15/10℃的昼夜温差下极少萌发。中光照下,种子发芽率略高于其它两种光照,无光照则完全抑制了种子萌发。去果皮处理可促进其萌发,各种覆盖物会导致种子发芽率下降。不同的萌发基质对萌发无影响。以上结果暗示,自然条件下太白山红桦种子的萌发将依赖于自然的扰动。
Pneumocystis diversity as a phylogeographic tool
Derouiche, S;Deville, M;Taylor, ML;Akbar, H;Guillot, J;Carreto-Binaghi, LE;Pottier, M;Aliouat, EM;Aliouat-Denis, CM;Dei-Cas, E;Demanche, C;
Memórias do Instituto Oswaldo Cruz , 2009, DOI: 10.1590/S0074-02762009000100017
Abstract: parasites are increasingly used to complement the evolutionary and ecological adaptation history of their hosts. pneumocystis pathogenic fungi, which are transmitted from host-to-host via an airborne route, have been shown to constitute genuine host markers of evolution. these parasites can also provide valuable information about their host ecology. here, we suggest that parasites can be used as phylogeographic markers to understand the geographical distribution of intra-specific host genetic variants. to test our hypothesis, we characterised pneumocystis isolates from wild bats living in different areas. bats comprise a wide variety of species; some of them are able to migrate. thus, bat chorology and migration behaviour can be approached using pneumocystis as phylogeographic markers. in the present work, we find that the genetic polymorphisms of bat-derived pneumocystis are structured by host chorology. therefore, pneumocystis intra-specific genetic diversity may constitute a useful and relevant phylogeographic tool.
Phylogeographic analysis of human papillomavirus 58
YanYun Li,ZuoFeng Li,YiFeng He,Yu Kang,XiaoYan Zhang,MingJun Cheng,Yang Zhong,CongJian Xu
Science China Life Sciences , 2009, DOI: 10.1007/s11427-009-0149-6
Abstract: Human papillomavirus 58 (HPV58) is one type of HPV with high risk of causing cervical cancer. Unusually high prevalence of HPV58 has been reported in Asia, Africa and some other areas. However, due to the scattered distribution of global data, in addition to the lack of data of some HPV58 high-incidence nations and regions, like Mainland China, a comprehensive analysis of the global geographical distribution of HPV58 remains blank so far. In this study, HPV58 from the human cervical cancer tissue was detected in Mainland China, and 14 new HPV58-E6/L1 gene sequences were obtained. Moreover, phylogeographic analysis has been conducted combining the HPV58 sequences that have been deposited in GenBank since 1985. The study result shows that the sequences detected from the Shanghai, Jiangsu and Sichuan areas are homologous with those found in the past from Hong Kong and Xi’an, China, as well as Japan and other Southeast Asian areas. Furthermore, Western Africa is considered to be the “root” source of the HPV58 variant, while Mainland China and Southeast Asia are “transit points” and the new sources of HPV58 after receiving the isolates from the “root” source; like HPV16 and HPV18, the HPV58 might also be one of the major HPV types associated with the development and spread of cervical cancer.
Reproductive isolation between phylogeographic lineages scales with divergence  [PDF]
Sonal Singhal,Craig Moritz
Quantitative Biology , 2013,
Abstract: Phylogeographic studies frequently reveal multiple morphologically-cryptic lineages within species. What is yet unclear is whether such lineages represent nascent species or evolutionary ephemera. To address this question, we compare five contact zones, each of which occurs between eco-morphologically cryptic lineages of rainforest skinks from the rainforests of the Australian Wet Tropics. Although the contacts likely formed concurrently in response to Holocene expansion from glacial refugia, we estimate that the divergence times (t) of the lineage-pairs range from 3.1 to 11.5 Myr. Multilocus analyses of the contact zones yielded estimates of reproductive isolation that are tightly correlated with divergence time and, for longer-diverged lineages (t > 5 Myr), substantial. These results show that phylogeographic splits of increasing depth can represent stages along the speciation continuum, even in the absence of overt change in ecologically relevant morphology.
Genetic Diversity and Distribution Patterns of Host Insects of Caterpillar Fungus Ophiocordyceps sinensis in the Qinghai-Tibet Plateau  [PDF]
Qing-Mei Quan, Ling-Ling Chen, Xi Wang, Shan Li, Xiao-Ling Yang, Yun-Guo Zhu, Mu Wang, Zhou Cheng
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0092293
Abstract: The caterpillar fungus Ophiocordyceps sinensis is one of the most valuable medicinal fungi in the world, and it requires host insects in family Hepialidae (Lepidoptera) to complete its life cycle. However, the genetic diversity and phylogeographic structures of the host insects remain to be explored. We analyzed the genetic diversity and temporal and spatial distribution patterns of genetic variation of the host insects throughout the O. sinensis distribution. Abundant haplotype and nucleotide diversity mainly existed in the areas of Nyingchi, ShangriLa, and around the edge of the Qinghai-Tibet Plateau, where are considered as the diversity center or micro-refuges of the host insects of O. sinensis. However, there was little genetic variation among host insects from 72.1% of all populations, indicating that the host species composition might be relatively simple in large-scale O. sinensis populations. All host insects are monophyletic except for those from four O. sinensis populations around Qinghai Lake. Significant phylogeographic structure (NST>GST, P<0.05) was revealed for the monophyletic host insects, and the three major phylogenetic groups corresponded with specific geographical areas. The divergence of most host insects was estimated to have occurred at ca. 3.7 Ma, shortly before the rapid uplift of the QTP. The geographical distribution and star-like network of the haplotypes implied that most host insects were derived from the relicts of a once-widespread host that subsequently became fragmented. Neutrality tests, mismatch distribution analysis, and expansion time estimation confirmed that most host insects presented recent demographic expansions that began ca. 0.118 Ma in the late Pleistocene. Therefore, the genetic diversity and distribution of the present-day insects should be attributed to effects of the Qinghai-Tibet Plateau uplift and glacial advance/retreat cycles during the Quaternary ice age. These results provide valuable information to guide the protection and sustainable use of these host insects as well as O. sinensis.
Exploring Phylogeographic Congruence in a Continental Island System  [PDF]
Julia Goldberg,Steven A. Trewick
Insects , 2011, DOI: 10.3390/insects2030369
Abstract: A prediction in phylogeographic studies is that patterns of lineage diversity and timing will be similar within the same landscape under the assumption that these lineages have responded to past environmental changes in comparable ways. Eight invertebrate taxa from four different orders were included in this study of mainland New Zealand and Chatham Islands lineages to explore outcomes of island colonization. These comprised two orthopteran genera, one an endemic forest-dwelling genus of cave weta (Rhaphidophoridae, Talitropsis) and the other a grasshopper (Acrididae, Phaulacridum) that inhabits open grassland; four genera of Coleoptera including carabid beetles ( Mecodema), stag beetles ( Geodorcus), weevils ( Hadramphus) and clickbeetles ( Amychus); the widespread earwig genus Anisolabis (Dermaptera) that is common on beaches in New Zealand and the Chatham Islands, and an endemic and widespread cockroach genus Celatoblatta (Blattodea). Mitochondrial DNA data were used to reconstruct phylogeographic hypotheses to compare among these taxa. Strikingly, despite a maximum age of the Chathams of ~4 million years there is no concordance among these taxa, in the extent of genetic divergence and partitioning between Chatham and Mainland populations. Some Chatham lineages are represented by insular endemics and others by haplotypes shared with mainland populations. These diverse patterns suggest that combinations of intrinsic (taxon ecology) and extrinsic (extinction and dispersal) factors can result in apparently very different biogeographic outcomes.
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