Land bridges : ancient environments, plant migrations, and New World connections / Alan Graham

Object Details

author

Graham, Alan 1934-

Contents

Introduction -- Part I. Boreal land bridges. Bering Land Bridge. Beringia. Background ; West Beringia : Siberia and Kamchatka. Siberia. Geographic setting and climate. Geology. Modern vegetation. Indigenous people ; Kamchatka. Geographic setting and climate. Modern vegetation. Indigenous people ; East Beringia : Alaska, northwestern North America, and the Aleutian connection. Geographic setting and climate. Geology. Modern vegetation. Indigenous people. Utilization of the Bering Land Bridge. Peopling of America (from the West) ; North Atlantic land bridge : northeastern North America, Greenland, Iceland, Arctic islands, northwestern Europe. Geographic setting and climate. Geology. Modern vegetation. Utilization of the North Atlantic land bridge. Modernization of the flora. Biodiversity and vegetation density. Floristic relationships between eastern Asia and eastern North America. Geofloras and the Madrean-Tethyan hypothesis. Indigenous people. Peopling of America (from the East) -- Part II. Equatorial land bridges. Antillean land bridge. Stepping stones or lost highway. Geographic setting and climate. Geology. Modern vegetation. Indigenous people. Utilization of the Antillean land bridge ; Central American land bridge. South and North of the CALB. Geographic setting and climate. Forging the final link : geology. Modern vegetation. Indigenous people. Utilization of the CALB -- Part III. Austral land bridge. Magellan land bridge : Cono del Sur and Antarctica. Cono del Sur. Geographic setting and climate. Geology. Modern vegetation. Indigenous people. Peopling of South America (from the North). Antarctica. Geographic setting and climate. Geology. Land bridges and island biogeography. Utilization of the Magellan land bridge. Cono del Sur. Antarctica ; Case studies. Ferns and allied groups. Gymnosperms. Angiosperms. Monocotyledons. Dicotyledons ; Summary and conclusions. Events, processes, and responses. Bering Land Bridge. North Atlantic land bridge. Antillean land bridge. Central American land bridge ; Magellan land bridge. Conceptual issues and future needs

Summary

"Land bridges are the causeways of biodiversity. When they form, organisms are introduced into a new patchwork of species and habitats, forever altering the ecosystems into which they flow; and when land bridges disappear or fracture, organisms are separated into reproductively isolated populations that can evolve independently. More than this, land bridges play a role in determining global climates through changes to moisture and heat transport and are also essential factors in the development of biogeographic patterns across geographically remote regions. In this book, paleobotanist Alan Graham traces the formation and disruption of key New World land bridges and describes the biotic, climatic, and biogeographic ramifications of these land masses' changing formations over time. Looking at five land bridges, he explores their present geographic setting and climate, modern vegetation, indigenous peoples (with special attention to their impact on past and present vegetation), and geologic history. From the great Panamanian isthmus to the boreal connections across the North Atlantic and North Pacific Oceans that allowed exchange of organisms between North America, Europe, and Asia, Graham's sweeping, one-hundred-million-year history offers new insight into the forces that shaped the life and land of the New World." -- From the rear cover.

2018

Type

Books

Physical description

xxiii, 310 pages : illustrations, maps ; 23 cm

Place

Western Hemisphere

Smithsonian Libraries

Topic

Natural bridges

Landforms

Biogeography

Plant diversity

Record ID

siris_sil_1104506

Metadata Usage (text)

CC0