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Books > Earth & environment > Earth sciences > Palaeontology > General
South America is home to some of the most distinctive mammals on
Earth—giant armadillos, tiny anteaters, the world's largest
rodent, and its smallest deer. But the continent once supported a
variety of other equally intriguing mammals that have no close
living relatives: armored mammals with tail clubs, saber-toothed
marsupials, and even a swimming sloth. We know of the existence of
these peculiar species thanks to South America's rich fossil
record, which provides many glimpses of prehistoric mammals and the
ecosystems in which they lived. Organized as a "walk through time"
and featuring species from 15 important fossil sites, this book is
the most extensive and richly illustrated volume devoted
exclusively to the Cenozoic mammals of South America. The text is
supported by 75 life reconstructions of extinct species in their
native habitats, as well as photographs of fossil specimens and the
sites highlighted in the book. An annotated bibliography is
included for those interested in delving into the scientific
literature.
This thesis encompasses a study of past precipitation patterns
based on six cave stalagmites from different parts of the Indian
Himalaya. This is the first speleothem study in the Indian Himalaya
that shows a direct relationship between past precipitation and the
collapse of civilization. The stalagmites examined were KL-3 from
Jammu and Kashmir; TCS and BR-1 from Himachal Pradesh; and DH-1,
SA-1 and CH-1 from Uttarakhand. Based on the high-resolution
palaeoclimatic reconstruction (35 U/th dates, 5 AMS dates, 1,500
samples for 18O and 13C values) obtained for the duration of the
Pleistocene-Holocene transition (16.2-9.5 ka BP) and
Mid-Holocene-Present (ca. 4.0 ka BP-Present), three major events
were identified, namely the Older Dryas (OD), Bolling-Allerod (BA)
period and Younger Dryas (YD) at ca. 14.3-13.9, 13.9-12.7 and
12.7-12.2 ka BP, respectively. The study showed a gradual reduction
in the precipitation from 4 ka BP onwards for about a millennium
with a peak arid period between 3.2 and 3.1 ka BP. According to the
findings, the LIA (Little Ice Age) covers a time span from
1622-1820 AD, during which the climate was wetter than that in the
post-LIA period (1820-1950 AD). In addition, this thesis supports
the assumption that the WDs (Western Disturbances) contribute
significantly to the total rainfall in the Himalaya region.
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