نتایج جستجو برای: plant fossils

تعداد نتایج: 407293  

2010
Jian Han Shin Kubota Hiro-omi Uchida George D. Stanley Xiaoyong Yao Degan Shu Yong Li Kinya Yasui

BACKGROUND Abundant fossils from the Ediacaran and Cambrian showing cnidarian grade grossly suggest that cnidarian diversification occurred earlier than that of other eumetazoans. However, fossils of possible soft-bodied polyps are scanty and modern corals are dated back only to the Middle Triassic, although molecular phylogenetic results support the idea that anthozoans represent the first maj...

Journal: :Current Biology 2014
David M. Martill

Pterosaur fossils are among the rarest and their eggs are even rarer. How then can we get an insight into the lifestyle of these flying reptiles? A wealth of new pterosaur fossils, including eggs, from China now provides exactly that.

2017
Nathan A Jud Maria A Gandolfo Ari Iglesias Peter Wilf

Southern-Hemisphere terrestrial communities from the early Paleocene are poorly known, but recent work on Danian plant fossils from the Salamanca Formation in Chubut Province, Argentina are providing critical data on earliest Paleocene floras. The fossils described here come from a site in the Salamanca Formation dating to ca. 1 million years or less after the end-Cretaceous extinction event; t...

Journal: :Journal of human evolution 2008
Andrew R Millard

The chronometric dating evidence for all hominid fossils from Africa and the Near East that have previously been dated to 500-50 ka is critically assessed using the concept of chronometric hygiene, and these dates are revised using Bayesian statistical analyses where possible. Sixteen relevant hominid sites lacking chronometric evidence are briefly discussed. Chronometric evidence from 37 sites...

2011
Peter N. Reinthal Andrew S. Cohen David L. Dettman

a r t i c l e i n f o Numerous biological and chemical paleorecords have been used to infer paleoclimate, lake level fluctuation and faunal composition from the drill cores obtained from Lake Malawi, Africa. However, fish fossils have never been used to examine changes in African Great Lake vertebrate aquatic communities nor as indicators of changing paleolimnological conditions. Here we presen...

2013
V. Lila Koumandou Bill Wickstead Michael L. Ginger Mark van der Giezen Joel B. Dacks Mark C. Field

Eukaryogenesis, the origin of the eukaryotic cell, represents one of the fundamental evolutionary transitions in the history of life on earth. This event, which is estimated to have occurred over one billion years ago, remains rather poorly understood. While some well-validated examples of fossil microbial eukaryotes for this time frame have been described, these can provide only basic morpholo...

Journal: :Brazilian Journal of Geology 2021

The Aptian Crato Formation is world renowned for its well-preserved fossils in microbially-induced laminated limestones, which are regarded as one of the main Cretaceous Konservat-Lagerstätte geological record. Detailed stratigraphic investigation and mapping up to 90-m-thick at eastern border Araripe Plateau allowed recognition a regionally persistent fossil-bearing muddy interval, herein defi...

Journal: :American journal of botany 2016
Brad R Ruhfel Claudia P Bove C Thomas Philbrick Charles C Davis

PREMISE OF THE STUDY The clusioid clade (Malpighiales) has an ancient fossil record (∼90 Ma) and extant representatives exhibit a pantropical distribution represented on all former Gondwanan landmasses (Africa, Australia, India, Madagascar, and South America) except Antarctica. Several biogeographers have hypothesized that the clusioid distribution is an example of Gondwanan vicariance. Our aim...

2013
Natalia Rybczynski John C. Gosse C. Richard Harington Roy A. Wogelius Alan J. Hidy Mike Buckley

The mid-Pliocene was a global warm period, preceding the onset of Quaternary glaciations. Here we use cosmogenic nuclide dating to show that a fossiliferous terrestrial deposit that includes subfossil trees and the northern-most evidence of Pliocene ice wedge casts in Canada's High Arctic (Ellesmere Island, Nunavut) was deposited during the mid-Pliocene warm period. The age estimates correspond...

Journal: :Photonics 2022

Fossilized plant remains have been studied simultaneously by laser induced fluorescence and Raman spectroscopies, to reveal the prospective methods for onsite or/and remote sensing in future extraterrestrial missions. A multiwavelength instrument, capable of measurements, has utilized study isolated fossils, as well fossils associated with sedimentary rocks. Laser-induced spectroscopy revealed ...

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