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Living Fossil in Illinois Waterways: Disappeared from 1990’s Water, Fish “Alligator Gar” is back in US Rivers

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Illinois' Powerton Lake was stocked with alligator gar in 2011, to re-establish a population and offer a challenge to sport fishermen. VOA
  • The Alligator gar is considered to be the second largest freshwater fish in North America
  • The origin of the fish dates back to Early Cretaceous period, over a 100 million years ago
  • Biologist Randy Sauer believes that with the return of the Alligator gar in Illinois waterways, post a long disappearance since the 1990s, will restore the ecosystem

The Illinois Department of Natural Resources is reintroducing a living fossil into its waterways. The alligator gar is a fish so old, it’s thought to have evolved during the Early Cretaceous period, more than a 100 million years ago.

Alligator gar are the second largest freshwater fish in North America. Illinois fisheries biologist Randy Sauer says they disappeared from the state’s waterways in the 1990s, although they continued to thrive in southern U.S. rivers.

“We want to restore the ecosystem because it is important to have top predators to balance the species below them in order to keep a check on some more abundant species,” he said.

“It was pretty much extirpated out of its range because of misconceptions about it eating sport fish,” he said. “People would target it and put bounties on it.”

Everything is on the menu

The alligator gar is an opportunistic feeder, meaning it will eat whatever it encounters — from an occasional turtle or small duck to invasive species such as Asian and silver carp. Sauer hopes the re-introduction program will help the state’s efforts to control the carp.

Alligator gar fingerlings about to be released into an Illinois river.

Because gar can live up to 60 years, this program is going to take decades to fully expand.

“The (female) alligator gar does not sexually mature until 11 years, and the male not till 6 or 7 years,” Sauer said, “so at the outset of this project we’re probably going to stock more heavily than 10 or 20 years down the road when hopefully these fish will find each other and start doing the job on their own.”

The transponders scientists use to track the released gars are just a little bigger than a grain of rice.

To date, 7,000 alligator gar fingerlings have been fitted with tiny transponder tags so that they can be tracked and then released into Illinois waterways. As it rains and floods, biologists expect some of the fish to follow the rivers all the way down to join other populations in Louisiana and Texas. (VOA)

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Oldest Evidence of Life on Earth Found in Eastern Canada, Says New Research

The recent research indicates that microbial life emerged earlier than previously known and relatively soon after the Earth's formation

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Microbiologist Maria Eugenia Farias from the National Scientific and Technical Research Council measuring the temperature and salinity of a hydrothermal vent in the crater of the Galan Volcano, at over 15,400 feet above sea level in Argentina. (VOA)

Canada, September 29, 2017 : Rocky outcrops in eastern Canada contain what may be some of the oldest evidence of life on Earth, dating back about 3.95 billion years.

Scientists said on September 27 that they found earliest indirect evidence of life on Earth in the form of bits of graphite contained in sedimentary rocks from northern Labrador that they believe are remnants of primordial marine microorganisms.

The researchers carried out a geological analysis of the Labrador rocks and measured concentrations and isotope compositions of the graphite, and concluded that it was produced by a living organism.

They did not find fossils of the microorganisms that may have left behind the graphite, a form of carbon, but said they may have been bacteria.

ALSO READ Discovery of 300,000-year-old Moroccan Fossils Shake Up Understanding of Human Origins

“The organisms inhabited an open ocean,” said University of Tokyo geologist Tsuyoshi Komiya, who led the study published in the journal Science.

Earth formed about 4.5 billion years ago and the oceans appeared roughly 4.4 billion years ago. The new study and some other recent research indicate that microbial life emerged earlier than previously known and relatively soon after the Earth’s formation.

Canada has produced some of the most ancient signs of life on Earth.

Another team of scientists in March reported that microfossils between 3.77 billion and 4.28 billion years old found in northern Quebec, relatively close to the Labrador site, are similar to the bacteria that thrive today around sea floor hydrothermal vents.

Other scientists last year described 3.7 billion-year-old fossilized microbial mats, called stromatolites, from Greenland. (VOA)

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Was Human Evolution an Accidental Progression?

A new study says that origin of human genus could have occurred by chance and might not be directly related to climate change

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Human Evolution
Human Evolution. Pixabay
  • A new study indicates that human evolution may not have been due to the climate change
  • Andrew Barr from George Washington University says that evolution may have happened by chance
  • There is no set-in-stone rule that species evolve due to climate change, it’s not yet discovered as to what causes change in this pulse

August 07, 2017: A new study says that origin of human genus could have occurred by chance and might not be directly related to climate change, as commonly believed.

Many scientists have argued that an influx, described as a “pulse”, of new animal species appears in the African fossil record between 2.8 and 2.5 million years ago, including our own genus Homo.

Experts believe it takes a broad-scale event like global climate change to spark the origination of so many diverse new species.

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However, the new study, published in the journal Paleobiology, says it is possible the pulse of new species could have occurred by chance.

“The idea that our genus originated more than 2.5 million years ago as part of a turnover pulse in direct response to climate change has a deep history in paleoanthropology,” said Andrew Barr from George Washington University.

“My study shows that the magnitude of that pulse could be caused by random fluctuations in speciation rates. One implication is that we may need to broaden our search for why our genus arose at that time and place,” Barr said.

Also Read: The Relationship Between Cats and Humans is More Than 10,000 Years Old, Find Out More

It is generally accepted that when major environmental changes occur, some species will go extinct and others will originate, which can create a cluster or pulse of new species in the fossil record.

However, there is not a set definition of what is considered a pulse, so experts have disagreed about which clusters constitute meaningful events and which can be explained as random fluctuations.

Barr used computer simulation to model what the fossil record might look like over time in the absence of any climate change and found clusters of species originations that were of similar magnitude to the clusters observed in the fossil record.

This means random patterns are likely under-credited for their role in speciation fluctuation, he said.

The findings mean scientists may need to rethink widely-accepted ideas about why human ancestors became smarter and more sophisticated. (IANS)

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‘Century-old Indian Dinosaur Fossils yet to be Recovered and Restored,’ says a British Geologist

A major chunk of the excavated bones were shipped to the British and American museums, and subsequently returned to India and presently housed in Indian Museum and GSI, Kolkata

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Dinosaur fossil in a museum. Representational image. Youtube

Kolkata, November 11, 2016: A section of fossil records of Indian dinosaurs, described by British geologist Charles Matley in the early 20th century, are yet to be traced and some, which are housed in the Indian Museum here, have not even been restored, an expert said.

“Some of the collections which he (Matley) claimed were restored back to India are missing over the last 100 years. Some of the specimens are in a bad shape and improperly stored. The challenge is to describe the collected material and restore it.

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“It is a big challenge to restore them as they are extremely fragile,” veteran palaeontologist D.M. Mohabey said at a national workshop on applications of palaeontology in archaeology at the museum on Wednesday.

“Restore the specimens which are misplaced. Some of the specimens packed in 1932 have not been opened yet. They are in writings of Matley,” he demanded.

Narrating the history of excavations of dinosaur fossils in India, Mohabey, a former Joint Director General of the Geological Survey of India (GSI), said the period 1917-33 was the first golden age of research on Indian dinosaurs when Matley carried out excavations in two expeditions (1917-1921 and 1932-1933) in the lameta sediments at Jabalpur (in now Madhya Pradesh) and at Pisdura (now Maharashtra).

Matley’s collections were subsequently distributed in three museums across the world: British Museum of Natural History (BMNH) (now the Natural History Museum), London, the American Museum of Natural History, New York (AMNH) and Indian Museum.

A major chunk of the excavated bones were shipped to the British and American museums for preparation and description, and subsequently returned to India and presently housed in Indian Museum and GSI, Kolkata, said Mohabey, adding the foreign museums still house critical specimens from the collection.

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“But at the same time a section of the specimens that he had collected were never taken to Britain.

“They lie here only, in the galleries of the Indian Museum which the GSI maintains. Many are in the same stage in which he had excavated and packed… they are still like that. Some of the collections were never opened,” he said.

The GSI and the University of Michigan have recently embarked on a programme to recover missing fossil bones in museum collections and to collect new bones from field sites.

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Efforts at the Indian Museum and GSI repositories have resulted in the recovery of the misplaced holotypic (a single specimen used as basis for original description of species) caudal vertebra of India’s first dinosaur, Titanosaurus indicus. (IANS)