Plastome Phylogenomics and Historical Biogeography of Aquatic Plant Genus Hydrocharis (Hydrocharitaceae)

Abstract Background Hydrocharis L. and Limnobium Rich. are small aquatic genera, including three and two species, respectively. The taxonomic status, phylogenetic relationships and biogeographical history of these genera have remained unclear, owing to the lack of Central African endemic H. chevalieri from all previous studies. We sequenced and assembled plastomes of all three Hydrocharis species and Limnobium laevigatum to explore the phylogenetic and biogeographical history of these aquatic plants. Results All four newly generated plastomes were conserved in genome structure, gene content, and gene order. However, they differed in size, the number of repeat sequences, and inverted repeat borders. Our phylogenomic analyses recovered non-monophyletic Hydrocharis. African species H. chevalieri was fully supported as sister to the rest of the species, and L. laevigatum was nested in Hydrocharis as a sister to H. dubia. Hydrocharis-Limnobium initially diverged from the remaining genera at ca. 53.3 Ma, then began to diversify at ca. 30.9 Ma. The biogeographic analysis suggested that Hydrocharis probably originated in Europe and Central Africa. Conclusion Based on the phylogenetic results, morphological similarity and small size of the genera, the most reasonable taxonomic solution to the non-monophyly of Hydrocharis is to treat Limnobium as its synonym. The African endemic H. chevalieri is fully supported as a sister to the remaining species. Hydrocharis mainly diversified in the Miocene, during which rapid climate change may have contributed to the speciation and extinctions. The American species of former Limnobium probably dispersed to America through the Bering Land Bridge during the Miocene.

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Plastome Phylogenomic and Biogeographical Study on Thuja (Cupressaceae)

BioMed Research International ◽

10.1155/2020/8426287 ◽

2020 ◽

Vol 2020 ◽

pp. 1-13

Author(s):

Kole F. Adelalu ◽

Xu Zhang ◽

Xiaojian Qu ◽

Jacob B. Landis ◽

Jun Shen ◽

...

Keyword(s):

North America ◽

East Asia ◽

Potential Effect ◽

Molecular Dating ◽

Disjunct Distribution ◽

Land Bridge ◽

Biogeographic History ◽

Extant Species ◽

History Of ◽

Phylogenomic Analyses

Investigating the biogeographical disjunction of East Asian and North American flora is key to understanding the formation and dynamics of biodiversity in the Northern Hemisphere. The small Cupressaceae genus Thuja, comprising five species, exhibits a typical disjunct distribution in East Asia and North America. Owing to obscure relationships, the biogeographical history of the genus remains controversial. Here, complete plastomes were employed to investigate the plastome evolution, phylogenetic relationships, and biogeographic history of Thuja. All plastomes of Thuja share the same gene content arranged in the same order. The loss of an IR was evident in all Thuja plastomes, and the B-arrangement as previously recognized was detected. Phylogenomic analyses resolved two sister pairs, T. standishii-T. koraiensis and T. occidentalis-T. sutchuenensis, with T. plicata sister to T. occidentalis-T. sutchuenensis. Molecular dating and biogeographic results suggest the diversification of Thuja occurred in the Middle Miocene, and the ancestral area of extant species was located in northern East Asia. Incorporating the fossil record, we inferred that Thuja likely originated from the high-latitude areas of North America in the Paleocene with a second diversification center in northern East Asia. The current geographical distribution of Thuja was likely shaped by dispersal events attributed to the Bering Land Bridge in the Miocene and subsequent vicariance events accompanying climate cooling. The potential effect of extinction may have profound influence on the biogeographical history of Thuja.

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Cenozoic History of the Bering Land Bridge: The seaway between the Pacific and Arctic basins has often been a land route between Siberia and Alaska

Science ◽

10.1126/science.129.3362.1519 ◽

1959 ◽

Vol 129 (3362) ◽

pp. 1519-1528 ◽

Cited By ~ 90

Author(s):

D. M. Hopkins

Keyword(s):

Land Bridge ◽

Bering Land Bridge ◽

The Pacific ◽

History Of

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The enigmatic history of the European, Asian and American plethodontid salamanders

Amphibia-Reptilia ◽

10.1163/15685381-00002893 ◽

2013 ◽

Vol 34 (3) ◽

pp. 323-336 ◽

Cited By ~ 20

Author(s):

David B. Wake

Keyword(s):

North America ◽

Close Relative ◽

Land Bridge ◽

Time Estimates ◽

Bering Land Bridge ◽

Plethodontid Salamanders ◽

New Information ◽

History Of ◽

Published Research ◽

American Clade

Recently published research addressing the question of relationships and biogeography of European plethodontid salamanders has refined time estimates for divergence from American relatives. The recently discovered Korean plethodontid Karsenia is either the sister-taxon of Hydromantes (which has members in Europe and California), or a close relative and co-member of a larger clade that originated in western North America, not eastern North America as formerly thought. The new information strengthens the biogeographical hypothesis that Hydromantes entered Eurasia via the Bering Land Bridge. Arguments are made favoring the placement of European and American relatives in a genus Hydromantes, with an American clade (subgenus Hydromantes) and a European clade (subgenera Atylodes and Speleomantes).

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Late Quaternary vegetation and climate history of the central Bering land bridge from St. Michael Island, western Alaska

Quaternary Research ◽

10.1016/s0033-5894(03)00068-1 ◽

2003 ◽

Vol 60 (1) ◽

pp. 19-32 ◽

Cited By ~ 66

Author(s):

Thomas A. Ager

Keyword(s):

Boreal Forests ◽

Vegetation Change ◽

Late Quaternary ◽

Land Bridge ◽

Climate History ◽

Middle Holocene ◽

Bering Land Bridge ◽

Dwarf Birch ◽

History Of ◽

Vegetation And Climate

AbstractPollen analysis of a sediment core from Zagoskin Lake on St. Michael Island, northeast Bering Sea, provides a history of vegetation and climate for the central Bering land bridge and adjacent western Alaska for the past ≥30,000 14C yr B.P. During the late middle Wisconsin interstadial (≥30,000–26,000 14C yr B.P.) vegetation was dominated by graminoid-herb tundra with willows (Salix) and minor dwarf birch (Betula nana) and Ericales. During the late Wisconsin glacial interval (26,000–15,000 14C yr B.P.) vegetation was graminoid-herb tundra with willows, but with fewer dwarf birch and Ericales, and more herb types associated with dry habitats and disturbed soils. Grasses (Poaceae) dominated during the peak of this glacial interval. Graminoid-herb tundra suggests that central Beringia had a cold, arid climate from ≥30,000 to 15,000 14C yr B.P. Between 15,000 and 13,000 14C yr B.P., birch shrub-Ericales-sedge-moss tundra began to spread rapidly across the land bridge and Alaska. This major vegetation change suggests moister, warmer summer climates and deeper winter snows. A brief invasion of Populus (poplar, aspen) occurred ca.11,000–9500 14C yr B.P., overlapping with the Younger Dryas interval of dry, cooler(?) climate. During the latest Wisconsin to middle Holocene the Bering land bridge was flooded by rising seas. Alder shrubs (Alnus crispa) colonized the St. Michael Island area ca. 8000 14C yr B.P. Boreal forests dominated by spruce (Picea) spread from interior Alaska into the eastern Norton Sound area in middle Holocene time, but have not spread as far west as St. Michael Island.

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Quaternary Correlations across Bering Strait: Recent Soviet and American studies cast new light on the history of the Bering land bridge

Science ◽

10.1126/science.147.3662.1107 ◽

1965 ◽

Vol 147 (3662) ◽

pp. 1107-1114 ◽

Cited By ~ 23

Author(s):

D. M. Hopkins ◽

F. S. MacNeil ◽

R. L. Merklin ◽

O. M. Petrov

Keyword(s):

American Studies ◽

Bering Strait ◽

Land Bridge ◽

Bering Land Bridge ◽

History Of

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Return to Beringia: parasites reveal cryptic biogeographic history of North American pikas

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2011.0482 ◽

2011 ◽

Vol 279 (1727) ◽

pp. 371-378 ◽

Cited By ~ 33

Author(s):

Kurt E. Galbreath ◽

Eric P. Hoberg

Keyword(s):

North America ◽

North American ◽

Land Bridge ◽

Biogeographic History ◽

Staging Area ◽

Ochotona Collaris ◽

Bering Land Bridge ◽

History Of ◽

Host Parasite

Traditional concepts of the Bering Land Bridge as a zone of predominantly eastward expansion from Eurasia and a staging area for subsequent colonization of lower latitudes in North America led to early inferences regarding biogeographic histories of North American faunas, many of which remain untested. Here we apply a host–parasite comparative phylogeographical (HPCP) approach to evaluate one such history, by testing competing biogeographic hypotheses for five lineages of host-specific parasites shared by the collared pika ( Ochotona collaris ) and American pika ( Ochotona princeps ) of North America. We determine whether the southern host species ( O. princeps ) was descended from a northern ancestor or vice versa. Three parasite phylogenies revealed patterns consistent with the hypothesis of a southern origin, which is corroborated by four additional parasite lineages restricted to O. princeps . This finding reverses the traditional narrative for the origins of North American pikas and highlights the role of dispersal from temperate North America into Beringia in structuring northern diversity considerably prior to the Holocene. By evaluating multiple parasite lineages simultaneously, the study demonstrates the power of HPCP for resolving complex biogeographic histories that are not revealed by characteristics of the host alone.

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A history of botanical collections in the Luangwa Valley, Zambia

Archives of Natural History ◽

10.3366/anh.1998.25.2.283 ◽

1998 ◽

Vol 25 (2) ◽

pp. 283-291

Author(s):

P.S.M. PHIRI ◽

D.M. MOORE

Keyword(s):

Eighteenth Century ◽

Environmental Impact ◽

Impact Assessment ◽

Vascular Plants ◽

Central Africa ◽

Peak Activity ◽

Historical Account ◽

History Of ◽

The 1960S ◽

Made In

Central Africa remained botanically unknown to the outside world up to the end of the eighteenth century. This paper provides a historical account of plant explorations in the Luangwa Valley. The first plant specimens were collected in 1897 and the last serious botanical explorations were made in 1993. During this period there have been 58 plant collectors in the Luangwa Valley with peak activity recorded in the 1960s. In 1989 1,348 species of vascular plants were described in the Luangwa Valley. More botanical collecting is needed with a view to finding new plant taxa, and also to provide a satisfactory basis for applied disciplines such as ecology, phytogeography, conservation and environmental impact assessment.

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From Stonehenge to Samarkand

10.1093/oso/9780195160918.001.0001 ◽

2006 ◽

Author(s):

Brian Fagan

Keyword(s):

Gustave Flaubert ◽

Central Africa ◽

British Museum ◽

Holy Land ◽

Cruise Ship ◽

Modern Times ◽

Ancient Civilization ◽

Machu Picchu ◽

History Of ◽

The Silk Road

Ever since Roman tourists scratched graffiti on the pyramids and temples of Egypt over two thousand years ago, people have traveled far and wide seeking the great wonders of antiquity. In From Stonehenge to Samarkand, noted archaeologist and popular writer Brian Fagan offers an engaging historical account of our enduring love of ancient architecture--the irresistible impulse to visit strange lands in search of lost cities and forgotten monuments. Here is a marvelous history of archaeological tourism, with generous excerpts from the writings of the tourists themselves. Readers will find Herodotus describing the construction of Babylon; Edward Gibbon receiving inspiration for his seminal work while wandering through the ruins of the Forum in Rome; Gustave Flaubert watching the sunrise from atop the Pyramid of Cheops. We visit Easter Island with Pierre Loti, Machu Picchu with Hiram Bingham, Central Africa with David Livingstone. Fagan describes the early antiquarians, consumed with a passionate and omnivorous curiosity, pondering the mysteries of Stonehenge, but he also considers some of the less reputable figures, such as the Earl of Elgin, who sold large parts of the Parthenon to the British Museum. Finally, he discusses the changing nature of archaeological tourism, from the early romantic wanderings of the solitary figure, communing with the departed spirits of Druids or Mayans, to the cruise-ship excursions of modern times, where masses of tourists are hustled through ruins, barely aware of their surroundings. From the Holy Land to the Silk Road, the Yucatán to Angkor Wat, Fagan follows in the footsteps of the great archaeological travelers to retrieve their first written impressions in a book that will delight anyone fascinated with the landmarks of ancient civilization.

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