Earth science

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Synopsis: Earth sciences: Earth science:

Over the past century, humans have been transforming the planet so profoundly that we are pushing it into a new geological era, the Anthropocene (the Age of man.

Or will something happen to push us off this trajectory oe perhaps back into Holocene-like conditions?

or Age of man, will be marked by a rapid decline in biodiversity as animals and plants disappear from the planet forever.

Ten thousand years ago, at the beginning of the Holocene geological epoch, the weight of humans and domesticated animals was just 0. 1%of the total.

In the Anthropocene (the Age of man), we have shifted this balance by releasing more carbon dioxide than plants can absorb.

Enriching the world's soilone of the biggest drivers of the Anthropocene-the age of man-is muck.

"Ten years from now, this is going to be like radiocarbon dating, Â says Fisher, referring to a standard technique now used by all archaeologists to date finds."

Some 10,000 years ago, at the beginning of the Holocene geological age, there were only around five million of us on the planet.

if humanity is to remain in the"safe operating space  of Holocene-like conditions,

Our population soared from around 10,000 individuals at the start of the Holocene, 10,000 years ago to 7 billion today.

Human scientists say Earth has entered the Anthropocene epoch oe the Age of man oe because we have become the dominant geological force on our planet.

Southern California Long Overdue for A major Earthquake A trench at the Bidart Fan sector of the San andreas fault. Researchers find major quakes on the southern section, on average,

Southern California is long overdue for a major earthquake along the San andreas fault, according to a landmark study of historic seismic activity released August 20, 2010.

found that earthquakes along the San andreas fault have occurred far more often than previously believed. For years, scientists have said major earthquakes occurred every 250 to 450 years along this part of the San Andreas. The new study found big temblors on the fault every 88 years, on average.

Other seismic experts described the revelation as a major change in the way they think about earthquake risks along the southern San andreas fault. Thomas Jordan,

They used carbon dating and sophisticated imaging technology known as lidar to find signs of earth movements.

The San andreas fault is considered one of the most dangerous in Southern California, partly because it is so long that its southern section is capable of producing a temblor as large as magnitude 8. 1. By contrast,

agricultural education is slimming down quite rapidly at tertiary level and physical infrastructure is being invested under,

or late Jurassic, said Michael Donoghue of Yale university. oemost molecular divergence times have shown that they might be older than that,

added Yale biologist Jeremy Beaulieu. oebut we actually find that they might be Triassic in origin,

The oldest algae crusts contained 646 years of layers confirmed by carbon dating the researchers said.

Peering back into the lineages of the bees the scientists noticed something unusual with all four groups beginning roughly 65 million years ago at the boundary between the Cretaceous and Paleogene periods.

The 10 Weirdest Animal Discoveries The end of the Cretaceous period corresponding to the beginning of the Paleogene Period was known already to be a dynamic time in history.

About 10 million years ago during a time period known as the Miocene epoch the east African climate became dryer

and piecing them together with radiocarbon dating and stratigraphic work would help piece together the chapters of the story Connor said.

The Evidence oehighest trees nowadays in Thailand are almost 60 meters (200 feet) Â wrote Philippe in response to my email query about his new paper coming out in the April issue of the journal Quaternary Science Reviews.

These well-preserved fossils discovered in two core samples drilled in northern Switzerland are about 245 million years old dating back to the earliest known dinosaur in the middle Triassic period.

However back in the middle Triassic both areas were located in the subtropics and the region that is now Switzerland was much drier than the Barents sea region suggesting the flowering plants spanned a broad range of environments.

Radiocarbon dating of the fossils gave researchers a 10000-year history of the past location of the ice.

#Cenozoic era: Facts About Climate, Animals & Plants The Cenozoic era which began about 65 million years ago

and continues into the present is documented the third era in the history of Earth. The current locations of the continents and their modern-day inhabitants including humans can be traced to this period.

The era began on a big down note catching the tail end of the Cretaceous-Paleogene extinction event at the close of the Cretaceous period that wiped out the remaining non-avian dinosaurs.

The term Cenozoic first spelled Kainozoic was used originally in an 1840 entry in the Penny Cyclopedia encyclopedia in an article written by British geologist John Phillips. The name is derived from the Greek phrase meaning oerecent life.

The Cenozoic era is divided into three periods: The global climate of the early portion of the Cenozoic Period was much warmer than it is today

and the overall climate of the Earth was much more consistent regardless of proximity to the equator.

The most significant period of global warming known as the Paleocene ocene Thermal Maximum took place of 55.8 million years ago.

Each segment of the Cenozoic experienced different climates. During the Paleogene Period most of the Earth s climate was tropical.

The Neogene Period saw a drastic cooling which continued into the Pleistocene epoch of the Quaternary period.

During the Pleistocene epoch glaciers covered central North america extending as far east as New york south to Kansas and Nebraska and west to the northern West Coast.

and the Rocky mountains were formed during the Cenozoic era. Life During the Cenozoic era The Cenozoic era is also known as the Age of mammals

because the extinction of many groups of giant mammals allowing smaller species to thrive and diversify because their predators no longer existed.

The beginning of the Paleogene Period was a time for the mammals that survived from the Cretaceous period.

Cave lions Sabre-toothed cats cave bears giant deer woolly rhinoceroses and woolly mammoths were prevailing species of the Quaternary period.

Without the dinosaurs plant life had an opportunity to flourish during the Cenozoic era. Nearly every plant living today had its roots in the Cenozoic era.

During the early part of the era forests overran most of North america. However as the climate cooled forests died off creating open land.

The Great lakes that formed in the western United states during the Eocene epoch were the perfect home for bass trout

and the one seen during the past 10000 years of geologic history called the Holocene during

what it has been during the Holocene say the study authors adding that doing so depends on the cumulative amount of emissions released into the atmosphere throughout the industrial period not just those emitted today.

In their new study Uno and his team tested the radiocarbon dating technique on the tusks of two elephants that died in 2006 and 2008 as well as elephant and hippo teeth monkey hair and oryx horn.

and Uno are also using the radiocarbon dating technique to investigate the growth rate of animals. Now that we can determine growth rates in teeth we can use them as a tape recorder of sorts Uno said.

Wasser envisioned the carbon-14 dating technique being useful in a variety of ways. For example if used in combination with other methods that use DNA to determine the geographical origin of an ivory sample the carbon-14 dating technique could help investigators determine how recently hotspots for elephant poaching have been active.

Also if the ivory in a large seizure included samples of multiple ages it might suggest that the ivory was obtained from government stockpiles

</p><p>The most recent and most familiar mass extinction is the one that finished the reign of the dinosaurs the end-Cretaceous

or Cretaceous-Tertiary extinction event often known as K-T. The only survivors among the dinosaurs are the birds.</

#Cretaceous period: Facts About Animals, Plants & Climate The Cretaceous period was the last and longest segment of the Mesozoic era.

It lasted approximately 79 million years from the minor extinction event that closed the Jurassic period about 145.5 million years ago to the Cretaceous-Paleogene (K-Pg) extinction event dated at 65.5 million years ago.

In the early Cretaceous the continents were in very different positions than they are today.

Sections of the supercontinent Pangaea were drifting apart. The Tethys Ocean still separated the northern Laurasia continent from southern Gondwana.

although the Central Atlantic had begun to open up in the late Jurassic period. By the middle of the period ocean levels were much higher most of the landmass we are familiar with was underwater.

Cretaceous period plants One of the hallmarks of the Cretaceous period was the development and radiation of the flowering plants.

Cretaceous period animals During the Cretaceous period birds replaced the Pterosaurs in the air. The origin of flight is debated by many experts.

and became widely diversified during the Cretaceous. Confuciusornis (125 to 140 million years) was sized a crow bird with a modern beak but enormous claws at the tips of the wings.

Dinosaurs That Learned To fly By the end of the Jurassic the giant Sauropods such as Apatosaurus were becoming extinct.

Evidence suggests that by the early Cretaceous they were being replaced by large herds of herbivorous Ornithischians such as Stegosaurus Iguanodon and the Ceratopsians.

Theropods including Tyrannosaurus rex continued as apex predators until the end of the Cretaceous. K-Pg extinction event About 65 million years ago nearly all large vertebrates and many tropical invertebrates became extinct in

because it marks the boundary between the Cretaceous and Paleogene periods. The event was formally known as the Cretaceous-Tertiary (K-T) event but the International Commission on Stratigraphy

which sets standards and boundaries for the geologic time scale now discourages the use of the term Tertiary.

The K is from the German word for Cretaceous Kreide. Â The Chicxulub crater in the Yucatan dates precisely to this time.

Cretaceous period climate All over North america the highest Cretaceous fossils are found directly beneath a thin layer of sediments that contain an unusual amount of iridium an element otherwise uncommon in Earth s crust.

and diversify in the new Cenozoic era e

#Crikey! Crocodiles and Alligators Snack on Fruit Crocodiles and alligators are infamous carnivores but it turns out they do not live on meat alone scientists have discovered unexpectedly that these predators occasionally snack on fruit as well.

Perhaps not but the crabs are a test case for how global warming will alter the migration of tropical species according to a Princeton university news release on the study nd Earth science is under the umbrella of NASA's mission.

To find out when this wet period took place the scientists used radiocarbon dating a technique that measures the ratio of different forms of carbon to find an object's age.

They did radiocarbon dating of shells on the lake's shoreline finding the shells'ages matched those of the other samples from formerly wet areas.

#Holocene epoch: The Age of man The Holocene epoch is the current period of geologic time. Another term that is sometimes used is the Anthropocene Epoch

because its primary characteristic is the global changes caused by human activity. This term can be misleading though;

The Holocene epoch began 12000 to 11500 years ago at the close of the Paleolithic Ice age

Holocene extinction Pressure from the human population has had far-reaching effects on the biodiversity of the planet.

Most people are familiar with the last mass extinction that closed the Cretaceous period 65 million years ago

We base our division of geologic time on evidence of changes in the life forms present On earth in different times.

We may be nearing the end of the Holocene epoch.

#Holy land Farming Began 5, 000 Years Earlier Than Thought AVDAT Israel For thousands of years different groups of people have lived in the Negev desert building stone walls

A great surprise Bruins'findings come from radiocarbon dating of bones and organic materials in various soil layers in an ancient field in southern Israel.

Carbon dating has been used to date famous objects such as the Dead sea scrolls. Gallery of Dead sea scrolls: A Glimpse of the Past I found a wonderful radiocarbon sequence of ages Bruins said.

Now investigators have found that three of these forested islands are shell middens piles of freshwater snail shells left by human settlers more than 10000 years ago according to carbon dating.

The Clovis culture Radiocarbon dating of two of the middens reveals an ancient human presence during the early Holocene period approximately 10400 years ago.

The samples enabled the scientists to peer back into the Arctic's climate history dating from 2. 2 million to 3. 6 million years ago during the middle Pliocene and early Pleistocene epochs.

Previous research suggests the proportion of carbon dioxide (CO2) in the atmosphere in the middle Pliocene and Early Pleistocene was similar to the levels that are recorded today

and attributed to man-made sources. If this is the case Earth's climate may be more sensitive to carbon dioxide than scientists previously thought Brigham-Grette said.

and levels in the Pliocene were thought to be similar to today Brigham-Grette explained. Some of the changes we see going on now sea ice melting tree lines migrating

and glaciers with tremendous ablation rate suggest that we're heading back to the Pliocene.

And a return to Pliocene-type conditions may not be too far off in the future said Gifford Miller a professor in the department of geological sciences at the University of Colorado Boulder who conducts research in the Canadian Arctic.

Rethinking the timeline The extended warm period during the middle Pliocene also raises new questions about the subsequent ice ages.

See Images of the Longhorn of Dinos Ancient micro-continent Though the region is parched now during the Cretaceous period

Fossil evidence suggests they evolved after the end-Cretaceous mass extinction event about 65 million years ago that ended the age of dinosaurs;

However genetics research suggests placental lineages were actually far older hinting their diversification was linked to the breakup of the continents before the end of the Cretaceous period.

The possible body size increase in the megalodon lineage over geologic time will need to be tested further by examining megalodon collections throughout the world

</p><p>This Cretaceous-era herbivore<i>Parasaurolophus</i>walked the Earth some 75 million years ago.

The rocks which carbon-dating of surrounding material showed to be between 4000 and 4800 years old were clustered in a tight pile.

Carbon dating suggested the area was occupied by humans from 7500 B c. to 4700 B c. roughly 5000 years prior to the erection of the first stones at Stonehenge.

#Paleozoic era: Facts & Information The Paleozoic era which ran from about 542 million years ago to 251 million years ago was a time of great change On earth.

The era began with the breakup of one supercontinent and the formation of another. Plants became widespread.

Life in the Paleozoic The Paleozoic began with the Cambrian period 53 million years best known for ushering in an explosion of life On earth.

This Cambrian explosion included the evolution of arthropods (ancestors of today's insects and crustaceans) and chordates (animals with rudimentary spinal cords.

 In the Paleozoic era life flourished in the seas. After the Cambrian period came the 45-million-year Ordovician period

which is marked in the fossil record by an abundance of marine invertebrates. Perhaps the most famous of these invertebrates was the trilobite an armored arthropod that scuttled around the seafloor for about 270 million years before going extinct.

 After the Ordovician period came the Silurian period (443 million years ago to 416 million years ago)

Those developments would appear in the Devonian period the next geological period of the Paleozoic. Ferns appeared as did the first trees.

The Devonian period saw the rise of the first land-living arthropods including the earliest ancestors of spiders.

Paleozoic evolution Life continued its march in the late Paleozoic. The Carboniferous period which lasted from about 359 million years ago to 299 million years ago answered the question

Which came first the chicken or the egg? definitively. Long before birds evolved tetrapods began laying eggs on land for the first time during this period allowing them to break away from an amphibious lifestyle.

because roaches'ancient ancestor (Archimylacris eggintoni) was found all across the globe during the Carboniferous.

The last period of the Paleozoic was the Permian period which began 299 million years ago and wrapped up 251 million years ago.

the Permian extinction. Before the Permian mass extinction though the warm seas teemed with life.

Coral reefs flourished providing shelter for fish and shelled creatures such as nautiloids and ammonoids. Modern conifers and ginkgo trees evolved on land.

During the Cambrian period of the Paleozoic the continents underwent a change. They had been joined as one supercontinent Rodinia

but during the Cambrian period Rodinia fragmented into Gondwana (consisting of what would eventually become the modern continents of the Southern hemisphere)

The Cambrian was warm worldwide but would be followed by an ice age in the Ordovician which caused glaciers to form sending sea levels downward.

Gondwana moved further south during the Ordovician while the smaller continents started to move closer together.

In the Silurian period the land masses that would become North america central and Northern europe and Western europe moved even closer together.

Sea levels rose again creating shallow inland seas. In the Devonian the northern land masses continued merging and they finally joined together into the supercontinent Euramerica.

Gondwana still existed but the rest of the planet was ocean. By the last period of the Paleozoic the Permian Euramerica and Gondwana became one forming perhaps the most famous supercontinent of them all:

Pangaea. The giant ocean surrounding Pangaea was called Panthalassa. Pangaea's interior was likely very dry

#Pleistocene epoch: Facts About the Last Ice age The Pleistocene epoch is defined typically as the time period that began about 1. 8 million years ago

and lasted until about 11700 years ago. The most recent Ice age occurred then as glaciers covered huge parts of the planet Earth.

The Pleistocene epoch is the first in which Homo sapiens evolved and by the end of the epoch humans could be found in nearly every part of the planet.

The Pleistocene epoch was the first epoch in the Quaternary period and the sixth in the Cenozoic era.

It was followed by the current stage called the Holocene epoch. At the time of the Pleistocene the continents had moved to their current positions.

At one point during the Ice age sheets of ice covered all of Antarctica large parts of Europe North america and South america and small areas in Asia.

Scientists identified the Pleistocene epoch s four key stages or ages Gelasian Calabrian Ionian and Tarantian.

The name Pleistocene is the combination of two Greek words: pleistos (meaning oemost) and kainos (meaning oenew or oerecent.

In 2009 the International Union of Geological Sciences established the start of the Pleistocene epoch at 1. 806 million years before the present.

One of the richest sources of information about life in the Pleistocene epoch can be found in the La Brea Tar pits in Los Angeles where remains of everything from insects to plant life to animals were preserved including a partial skeleton of a female human and a nearly complete woolly mammoth.

Other than a few birds that were classified as dinosaurs most notably the Titanis there were no dinosaurs during the Pleistocene epoch.

They had become extinct at the end of the Cretaceous period more than 60 million years before the Pleistocene epoch began.

World's Weirdest Geological formations In addition because Bald cypress trees can live a thousand years and there are so many of them the trees could contain thousands of years of climate history for the region Harley said.

which were deposited in the Triassic period. The fish balls sized from kumquat to mandarin appeared on a return visit in March 2013.

As part of that work the university has major research partnerships with federal agencies in Earth science climate and energy research.

Photos of Exotic Food However one true tale of a Pleistocene repast comes from the University of Alaska Fairbanks. Paleontologist Dale Guthrie

Some 250 million years ago during the late Permian and early Triassic the world was a greenhouse much hotter than it is today.

Levels of CO2 haven't been that high since the Pliocene epoch between 3 million and 5 million years ago according to the Scripps Institution of Oceanography.

The last time Earth's atmospheric levels of CO2 reached 400 ppm was during the Pliocene epoch between 5 million and 3 million years ago according to the University of California San diego's Scripps Institution of Oceanography.

Facts, Information & Lodging Yosemite national park created in 1890 is one of the oldest nature preserves in the United states. A wonderland of geological formations

and fossilized poop or coprolites of eight Pleistocene beasts woolly mammoths rhinos bison and horses found in museums throughout the world.

This rock deposit is a natural time capsule from the Late Cretaceous period just before a mass extinction wiped out the dinosaurs.

#Permian period: Climate, Animals & Plants The Permian period was the final period of the Paleozoic era. Lasting from 299 million to 251 million years ago it followed the Carboniferous period

and preceded the Triassic period. By the early Permian the two great continents of the Paleozoic Gondwana and Euramerica had collided to form the supercontinent Pangaea.

Pangaea was shaped like a thickened letter C.#The top curve of the C# consisted of landmasses that would later become modern Europe and Asia.

North and South america formed the curved back of the C# with Africa inside the curve.

India Australia and Antarctica made up the low curve. Inside the C# was the Tethys Ocean

Because Pangaea was so immense the interior portions of the continent had a much cooler drier climate than had existed in the Carboniferous.

and spiny fishes that gave rise to the amphibians of the Carboniferous were being replaced by true bony fish.

On land the giant swamp forests of the Carboniferous began to dry out. The mossy plants that depended on spores for reproduction were being replaced by the first seed-bearing plants the gymnosperms.

Arthropods continued to diversify during the Permian period to fill the niches opened up by the more variable climate.

and sucking plant materials evolved during the Permian. Other new groups included the cicadas and beetles.

Two important groups of animals dominated the Permian landscape: Synapsids and Sauropsids. Synapsids had skulls with a single temporal opening

In the early Permian it appeared that the Synapsids were to be the dominant group of land animals.

In the late Permian Pelycosaurs were succeeded by a new lineage known as Therapsids. These animals were much closer to mammals.

At the end of the Permian the largest Synapsids became extinct leaving many ecological niches open. The second group of land animals the Sauropsid group weathered the Permian Extinction more successfully

and rapidly diversified to fill them. The Sauropsid lineage gave rise to the dinosaurs that would dominate the Mesozoic era.

The Permian period ended with the greatest mass extinction event in Earth s history. In a blink of Geologic time in as little as 100000 years the majority of living species on the planet were wiped out of existence.

Scientists estimate that more than 95 percent of marine species became extinct and more than 70 percent of land animals.

Fossil beds in the Italian Alps show that plants were hit just as hard as animal species. Fossils from the late Permian show that huge conifer forests blanketed the region.

These strata are followed by early Triassic fossils that show few signs of plants being present

but instead are filled with fossil remnants of fungi that probably proliferated on a glut of decaying trees.

Whatever the cause the Great Dying closed the Paleozoic era e

#Whoops! Amazon Green-Up Actually Satellite Error Surprising dry season growth spurts spotted in the beleaguered Amazon rainforest are fake the result of misleading satellite data a new study finds.

</p><p>This snippet of the Cretaceous ended up frozen in rock and paleontologists discovered the prints as early as 1917.

The new fossils date back about 50 million to 53 million years ago to the warm Eocene epoch

Greenwood and his colleagues found it in coal-rich rock beds in the park the site of a swampy spot in the Eocene

which started out evolutionarily the size of a mini schnauzer shrunk to housecat size during the warmest part of the early Eocene.)

which makes sense as it shows up in many forested Eocene environments Eberle said. The early Eocene was a steamy time On earth.

The breakup of the supercontinent Pangea came with no small amount of volcanic activity which released billions of tons of carbon dioxide into the atmosphere.

There are rock art drawings of hippopotamuses and rhinoceroses from the early Holocene. The tombs of Egyptian pharaohs are decorated with hunting scenes that show

The researchers found that Egypt was home to 37 large-bodied mammals (those over 8. 8 lbs. or 4 kilograms) during the Late Pleistocene and early Holocene.

However our findings show that cave art was made at opposite ends of the Pleistocene Eurasian world at about the same time suggesting these practices have deeper origins perhaps in Africa before our species left this continent and spread across the globe.

Eighty percent of the planet's species died off at the end of the Cretaceous period 65.5 million years ago including most marine life in the upper ocean as well as swimmers and drifters in lakes and rivers.

and her team concluded that the leafcutter bees lived in a low-elevation moist environment during the Late Pleistocene.

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