A case in point is the Cambrian explosion the sudden appearance about 540 million years ago of a remarkable diversity of animal species without apparent predecessors.
but in other places it will be grassland says Charles Koven a scientist in Berkeley Lab's Earth sciences Division who conducted the research.
biofuel productionhydrogen sulfide the pungent stuff often referred to as sewer gas is a deadly substance implicated in several mass extinctions including one at the end of the Permian period 251 million years ago that wiped out more than three-quarters of all species
when sulfates in the oceans were decomposed by sulfur bacteria is believed to have played a significant role in several extinction events in particular the Great Dying at the end of the Permian period.
In the 1950s scientists tested this correlation using early radiocarbon dating but the large error range left open the validity of GMT.
United states 517-432-4412 rosejo@msu. edulinking advances in genomics research mathematics and earth sciences as well as novel engineering technologies is imperative
and coincided with the abrupt climate change that occurred during the Pliocene epoch. They also found the expansion of the micro-RNA mir2275 family may contribute to Ae.
One leading analysis based on genomic data alone predicted that a number of placental mammal lineages existed in the Late Cretaceous
and survived the Cretaceous-Paleogene extinction. It has been suggested that primates diverged from other mammals well before the extinction of the dinosaurs
and spanned the late Cretaceous when dinosaurs roamed and the early Paleogene when mammals began to diversify.
Lee professor of Earth science at Rice led the four-year study which was authored co by three Rice faculty members and additional colleagues at the University of Tokyo the University of British columbia the California Institute of technology Texas A&m University and Pomona College.
Jerry was talking about seawater in the Cretaceous and he mentioned that 93.5 million years ago there was a mass extinction of deepwater organisms that coincided with a global marine anoxic event--that is the deep oceans became starved of oxygen Lee said.
Tectonic and petrological evidence indicated that many Etna-like volcanoes existed during the Cretaceous greenhouse Lee said.
Rice co-authors include Dickens and Lenardic both professors of Earth science; Rajdeep Dasgupta assistant professor of Earth science;
Bing Shen postdoctoral research associate; Benjamin Slotnick graduate student; and Kelley Liao a graduate student who began work on the project as undergraduate.
and pollen evidence that allows us to say just how long we've seen Serengeti-type open grasslands said Sarah J. Feakins assistant professor of Earth sciences at the USC Dornsife College of Letters Arts
The types of grasses appear to be sensitive to global carbon dioxide levels said Liddy who is currently working to refine the data pertaining to the Pliocene to provide an even clearer picture of a period that experienced similar atmospheric carbon dioxide levels to present day.
Some of the radiocarbon dating work was undertaken at the Natural Environment Research Council Radiocarbon Facility (Environment.
and visualizing Earth science data from a NASA and U s. Geological Survey satellite program is resulting in for the first time the ability to tease out the small events that can cause big changes in an ecosystem.
but could not demonstrate the existence of deeper silicate magma said Dasgupta an assistant professor of Earth science at Rice.
Study co-author Brandon Dugan assistant professor of Earth science at Rice said We hypothesize that this is likely due to the presence of two flow paths for water through soil-biochar mixtures.
The fossilized leaf samples span the last 1400000 years of the Cretaceous and the first 800000 of the Paleogene.
which at the end of the Cretaceous was a lowland floodplain crisscrossed by river channels. The collection consists of more than 10000 identified plant fossils
Radiocarbon dating of ancient peach stones (pits) discovered in the Lower Yangtze river Valley indicates that the peach seems to have been diverged from its wild ancestors as early as 7500 years ago.
Scientists also found similarities to 600 million year-old Precambrian extinct life forms suggested by some to be failed early
The team also reanalyzed vein density data from the literature from the Early Cretaceous (132.5 million years ago) to the Paleocene (58 million years ago) to determine
Vein density values similar to present ones appeared about 58 million years ago indicating that the emergence of flowering plants in the canopy occurred by the Paleocene.
For more information about NASA's Earth science activities in 2014 visit: http://www. nasa. gov/earthrightnowstory Source:
For more information about NASA's Earth science activities in 2014 visit: http://www. nasa. gov/earthrightnowstory Source:
One of the warmest periods was the early Eocene epoch 50 to 53 million years ago.
The early Eocene is a time in the geological past that helps us understand how present day Canada came to have the temperate plants
The study indicates the Eocene Arctic sand tiger shark a member of the lamniform group of sharks that includes today's great white thresher
In contrast modern sand tiger sharks living today in the Atlantic ocean are very intolerant of low salinity requiring three times the saltiness of the Eocene sharks
The ancient sand tiger sharks that lived in the Arctic during the Eocene were very different than sand tiger sharks living in the Atlantic ocean today.
The new findings on Arctic ocean salinity conditions in the Eocene were calculated in part by comparing ratios of oxygen isotopes locked in ancient shark teeth found in sediments on Banks Island in the Arctic circle
The Eocene epoch which ran from about 56 to 34 million years ago was marked by wild temperature fluctuations including intense greenhouse periods
and plants that were living in the Eocene Arctic greenhouse period said Eberle. To finally get some data on the Eocene marine environment using these shark teeth will help us to begin filling in the gaps.
Eberle said the Eocene Arctic ocean was isolated largely from the global oceans. Increased freshwater runoff from the land due to an intensified hydrologic cycle and a humid Arctic would have turned it more brackish pretty quickly she said.
The salinity gradient across the Eocene Arctic ocean that provided habitat for the ancient sand tiger sharks also was found to be much larger than the salinity gradient tolerated by modern sand tiger sharks living in the Atlantic ocean said Eberle.
The Eocene lamniform group of sharks had a much broader environmental window than lamniform sharks do today.
Eberle and Kim said the early-middle Eocene greenhouse period from 53 to 38 million years ago is used as a deep-time analog by climate scientists for
what could happen On earth if CO2 and other greenhouse gases in Earth's atmosphere continue to rise and
director in the NSF's Division of Earth sciences which co-funded the research with NSF's Division of Polar Programs.
The beech in Central europe is a relic of the warmer temperatures that prevailed during the Tertiary period;
Timeframes are identified through radiocarbon dating of freshwater snail shells and other organic soil matter. Thin microscopic sections of dirt samples show organization of soil grains revealing
because they are there here we have a throwback to the Pleistocene; it is still here
what the Cretaceous forests looked like with and without fire disturbance says Hans Larsson Canada Research Chair in Macroevolution at Mcgill University.
Dominating hypotheses point out Pleistocene glaciations--which took place between 2. 5 years ago and 20000 years ago--or Tertiary tectonic geological reorganizations Tertiary
and more recent evolutionary processes whereas Pleistocene climate changes had a minor influence in generating present-day diversity
Moreover most sampled localities harbour high levels of genetic diversity with lineages sharing common ancestors that predate the Pleistocene (more than 2. 5 million years ago.
and in the ocean storing carbon dioxide in a liquefied form in underground geological formations and wells increasing Earth's cloud cover and solar reflection.
which oil and coal extraction companies then pump into underground geological formations and wells and cap;
may have led to extinctionnewly analyzed tooth samples from the great apes of the Miocene indicate that the same dietary specialization that allowed the apes to move from Africa to Eurasia may have led to their extinction according to results published May 21 2014 in the open access journal
Apes expanded into Eurasia from Africa during the Miocene (14 to 7 million years ago)
and lower molars belonging to apes from five extinct taxa found in Spain from the mid-to late-Miocene (which overall comprise a time span between 12. 3â#2. 2 and 9. 7 Ma).
and Turkey suggested that the great ape's diet evolved from hard-shelled fruits and seeds to leaves but these findings only contained samples from the early-Middle and Late Miocene while lack data from the epoch of highest diversity
and seeds at the beginning of the movement of great apes to Eurasia soft and mixed fruit-eating coexisted with hard-object feeding in the Late Miocene
Some other discouraging news came from Lonnie Thompson Distinguished University Professor in the School of Earth sciences and Senior Research Scientist at BPRC:
Among these the world's oldest-known grape species Indovitis chitaleyae discovered in 2005 and described in 2013 pushed the record of the Vitaceae (grape) family into the Late Cretaceous about 66 million years ago.
Lead researcher Nerilie Abram from the ANU Research School of Earth sciences said the findings explained the mystery over why Antarctica was not warming as much as the Arctic and why Australia faces more droughts.
Currano assistant professor of geology and environmental earth science Miami University of Ohio; Conrad C. Labandeira department of paleobiology Smithsonian Institution and department of entomology University of Maryland.
Five new NASA Earth science missions are launching in 2014 to expand our understanding of Earth's changing climate and environment.
and how much of it breaks down along the way said Masiello associate professor of Earth science at Rice.
The researchers used radiocarbon dating and other techniques to examine the black carbon that was buried in seafloor sediments in the Northeast Pacific that dated to about 20000 years ago.
For more information about NASA's Earth science activities in 2014 visit: http://www. nasa. gov/earthrightnowstory Source:
#Dry future climate could reduce orchid bee habitatduring Pleistocene era climate changes neotropical orchid bees that relied on year-round warmth
By proceeding with the caveat that physiological tolerance has remained constant--species tend to be evolutionarily conservative about shifting their niches--the researchers used computer models to simulate past bee distributions based on climate conditions in the Pleistocene.
For more information about NASA's Earth science activities in 2014 visit: http://www. nasa. gov/earthrightnowstory Source:
The latest evidence for antedating the eruption was supplied by a study from Denmark that used radiocarbon dating (14c dating) to examine olive wood from the period of the eruption.
Their findings reveal that dung beetles were much more frequent in the previous interglacial period (from 132000 to 110000 years ago) compared with the early Holocene (the present interglacial period before agriculture from 10000 to 5000 years ago.
One of the surprising results is that woodland beetles were much less dominant in the previous interglacial period than in the early Holocene
Euan G. Nisbet Foundation Professor of Earth sciences at Royal Holloway maintains an Atlantic network of greenhouse gas measurements.
The evidence places the two earthquakes in 1838 and 1890 on the San andreas fault as theorized by many researchers based on written accounts about damage to Spanish-built missions in the Monterey and San francisco bay areas.
sub-fault of the San andreas fault zone. That quake which disrupted baseball's World series forced her family to camp outside their home.
High-resolution radiocarbon dating of tree-rings from the wood chips and charcoal confirm these are post European deposits
and like the 1989 event occurred on a sub zone of the San andreas fault. Conventional thinking Streig said has suggested that the San andreas fault always ruptures in a long-reaching fashion similar to the 1906 earthquake.
This study is the first to show three historic ruptures on the San andreas fault outside the special case of Parkfield Weldon said referring to a region in mountains to the south of the Santa cruz range where six magnitude 6-plus earthquakes occurred between 1857 and 1966.
but now we know the San andreas fault ruptured three times on the same piece of the fault in less than 100 years.
This research furthers our understanding of the connectivity of the various sections of California's San andreas fault
and builds on a range of the university's previous collaborative projects which span its departments of Chemistry Biology Earth sciences and the Durham Business school.**
and methane during the mid-Pliocene epoch were twice the levels observed in the preindustrial era--largely
These findings help explain why the Pliocene was two to three degrees C warmer than the preindustrial era
Climate scientists have suggested that the Pliocene epoch might provide a glimpse of the planet's future
During the Pliocene the two main factors believed to influence the climate--atmospheric CO2 concentrations
But scientists have wondered long why the Pliocene's global surface air temperatures were so much warmer than Earth's preindustrial climate.
Forest cover was vastly greater during the Pliocene a period marked not just by warmer temperatures
Using the NASA Goddard Institute for Space Studies Model-E2 global Earth system model the researchers were able to simulate the terrestrial ecosystem emissions and atmospheric chemical composition of the Pliocene and the preindustrial era.
According to their findings the increase in global vegetation was the dominant driver of emissions during the Pliocene--and the subsequent effects on climate.
The new study argues otherwise saying that the particles lingered about the same length of time--one to two weeks--in the Pliocene atmosphere compared to the preindustrial.
We grew teosinte in the conditions that it encountered 10000 years ago during the early Holocene period:
Piperno and Winter devised a scheme to essentially travel back in time by comparing plants grown in modern conditions with plants grown in the early Holocene chamber.
when in the Holocene teosinte became the plant very distinctive from maize in vegetative architecture
A study published in January 2014 in the ornithological journal The Auk provided the very first evidence of largely modern Hoatzins from the Miocene (15 million years ago) in Africa.
The fossils belong to a newly described species Protoazin parisiensis (proto-Hoatzin from Paris). The re-interpretation of these bones indicates that hoatzins lived in Europe as early as the late Eocene i e. around 34 million years ago.
Most notably Hoatzins appear to have become extinct in Europe much earlier than in Africa where the latest fossils were dated as of Miocene age (15 million years ago)
The newly discovered species were preserved in Eocene epoch fossil beds that are 49 million to 52 million years old
By the time of these flies in the Eocene however forests had diversified again but this time with many new kinds of flowering plants that are familiar to us today such as birches maples and many others.
The researchers report in the current issue of American Journal of Botany that Agathis was a dominant keystone element of the Patagonian Eocene floras alongside numerous other plant taxa that still associate with it in Australasia and Southeast asia.
Laguna del Hunco that dates to the early Eocene at about 52.2 million years ago and RÃ o Pichileufã dating to about 47.7 million years ago.
which reveals the oldest evidence of sexual reproduction in a flowering plant--a cluster of 18 tiny flowers from the Cretaceous period--with one of them in the process of making some new seeds for the next generation.
The perfectly-preserved scene in a plant now extinct is part of a portrait created in the mid-Cretaceous
During the Cretaceous new lineages of mammals and birds were beginning to appear along with the flowering plants.
shared with its predecessors, the primates of the Miocene epoch, and derived traits, which it shares exclusively with later hominids.
And as such the Athropocene the age of humans is proposed the term for our current geological time scale,
marking the end of the Holocene about 200 years ago. If technological innovation brought humans to a population of 7 billion can it also make the future planet livable?
are worried we enough about saving human civilization to make this time scale, the Anthropocene, more than a mere speck in the geologic time scale?
the Holocene, may have come to a close, and we humans where the â Å anthro â Â part of the name comes from may be largely responsible for the shift.
The Holocene got its start when the last ice age ended and we shifted from a glacial ice covering much of the northern hemisphere,
which was the end of the Pleistocene. The Holocene may have ended when James Watt invented his steam engine.
And we started pumping out CO2 by burning coal. So in addition to the climate change we have raised greenhouse gasses in the atmosphere by about 100 parts per million (ppm)
That is a huge change compared to only a third of the Earth surface was covered by ice at the end of the Pleistocene and the shift into the Holocene,
We are putting carbon that was locked away during the Cretaceous period 300 million years ago, back into the atmosphere as CO2.
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