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Showing posts with label Ticker. Show all posts
Showing posts with label Ticker. Show all posts

Friday, April 21, 2017


The most comprehensive study on the bones of Homo floresiensis, a species of tiny human discovered on the Indonesian island of Flores in 2003, has found that they most likely evolved from an ancestor in Africa and not from Homo erectus as has been widely believed.

Indonesian ‘hobbits’ not related to Homo erectus
Artist's impression of Homo floresiensis [Credit: Katrina Kenny, SA Museum]
The study by The Australian National University (ANU) found Homo floresiensis, dubbed "the hobbits" due to their small stature, were most likely a sister species of Homo habilis -- one of the earliest known species of human found in Africa 1.75 million years ago.

Data from the study concluded there was no evidence for the popular theory that Homo floresiensis evolved from the much larger Homo erectus, the only other early hominid known to have lived in the region with fossils discovered on the Indonesian mainland of Java.

Study leader Dr Debbie Argue of the ANU School of Archaeology & Anthropology, said the results should help put to rest a debate that has been hotly contested ever since Homo floresiensis was discovered.

"The analyses show that on the family tree, Homo floresiensis was likely a sister species of Homo habilis. It means these two shared a common ancestor," Dr Argue said.

"It's possible that Homo floresiensis evolved in Africa and migrated, or the common ancestor moved from Africa then evolved into Homo floresiensis somewhere."

Indonesian ‘hobbits’ not related to Homo erectus
A reconstructed skull of Homo floresiensis [Credit: Stuart Hay, ANU]
Homo floresiensis is known to have lived on Flores until as recently as 54,000 years ago.

The study was the result of an Australian Research Council grant in 2010 that enabled the researchers to explore where the newly-found species fits in the human evolutionary tree.

Where previous research had focused mostly on the skull and lower jaw, this study used 133 data points ranging across the skull, jaws, teeth, arms, legs and shoulders.

Dr Argue said none of the data supported the theory that Homo floresiensis evolved from Homo erectus.

"We looked at whether Homo floresiensis could be descended from Homo erectus," she said.

"We found that if you try and link them on the family tree, you get a very unsupported result. All the tests say it doesn't fit -- it's just not a viable theory."


Dr Argue said this was supported by the fact that in many features, such as the structure of the jaw, Homo floresiensis was more primitive than Homo erectus.

"Logically, it would be hard to understand how you could have that regression -- why would the jaw of Homo erectus evolve back to the primitive condition we see in Homo floresiensis?"

Dr Argue said the analyses could also support the theory that Homo floresiensis could have branched off earlier in the timeline, more than 1.75 million years ago.

"If this was the case Homo floresiensis would have evolved before the earliest Homo habilis, which would make it very archaic indeed," she said.

Professor Mike Lee of Flinders University and the South Australian Museum, used statistical modeling to analyse the data.

"When we did the analysis there was really clear support for the relationship with Homo habilis. Homo floresiensis occupied a very primitive position on the human evolutionary tree," Professor Lee said.

"We can be 99 per cent sure it's not related to Homo erectus and nearly 100 per cent chance it isn't a malformed Homo sapiens," Professor Lee said.

Source: Australian National University [April 21, 2017]

Indonesian ‘hobbits’ not related to Homo erectus

The most comprehensive study on the bones of Homo floresiensis, a species of tiny human discovered on the Indonesian island of Flores in 200...

Thursday, April 20, 2017


Our earliest mammalian ancestors likely skulked through the dark, using their powerful night-time vision to find food and avoid reptilian predators that hunted by day. This conclusion, published by Stanford researchers in Scientific Reports, used genetic data to support existing fossil evidence suggesting that our distant relatives may have adapted to life in the dark.

Genetic evidence suggests early mammals were nocturnal
Many modern mammals, like this wood rat, are nocturnal, thanks to evolutionary developments such as night vision 
in their distant ancestors, Stanford researchers say [Credit: Damian Kuzdak/Getty Images]
The team, led by Liz Hadly, professor of biology and senior author on the paper, examined genes involved in night vision in animals throughout the evolutionary tree, looking for places where those genes became enhanced.

"This method is like using the genome as a fossil record, and with it we've shown when genes involved in night vision appear," Hadly said. "It's a very powerful way of corroborating a story that has been, up to now, only hypothesized."

Mammals versus reptiles

Mammals and reptiles share a common ancestor, with the earliest mammal-like animals appearing in the Late Triassic (about 200 million years ago). Fossil evidence suggests that early mammals had excellent hearing and sense of smell and were likely also warm-blooded. All of these features are common in their descendants, the living mammals, most of whom are nocturnal. Therefore, experts have hypothesized that early mammals were also nocturnal. This study offers direct, genetic evidence for that hypothesis.

To trace the evolution of nocturnality, the researchers studied genes that the lead author, visiting scholar Yonghua Wu, had previously found associated with night vision in certain birds, such as owls. The team members examined those night-vision genes in many mammals and reptiles, including snakes, alligators, mice, platypuses and humans. Using what they know about how those animals are related, they figured out when in their evolutionary histories, if ever, the function of these genes was enhanced.

From this, they deduced that the earliest common ancestor did not have good night vision and was instead active during the day. However, soon after the split, mammals began enhancing their night vision genes, allowing them to begin to roam at night, thus avoiding the reptiles that hunted during the day.

"Early mammals coexisted with early reptiles in the Age of the Dinosaurs and somehow escaped extinction," Wu said. "This research further supports the hypothesis that diurnal reptiles, such as lizards, snakes and their relatives, competed with mammals and may have led them to better adapt to dim light conditions."

In the millions of years that have elapsed since mammals and reptiles diverged, natural selection and evolution haven't stopped. Not all mammals are still nocturnal. Some groups of mammals have reoccupied the day, adapting in various ways to daylight activity. These animals include cheetahs, pikas, camels, elephants, and, of course, humans.

"Understanding the constant pressure to get better at seeing the world at night for over 100 million years is a beautiful way of thinking about evolution," Hadly said. "We think of it as something simple -- seeing in the light or the dark -- but these genes are being constantly refined and altered by natural selection."

Filling in our history

The methods used by these researchers could be applied to different areas of the animal evolutionary tree to learn more about the evolution of vision, including how humans made the switch to bright-light vision. This study is also an example of how little information we have about the first mammals, compared to what we know about our ancient and more compelling reptile cousins, the dinosaurs.

"When people talk about the dinosaur age, even when you look at cartoons, the focus is mainly on dinosaurs," said Haifeng Wang, co-author of the paper and postdoctoral research fellow with Stanley Qi, an assistant professor of bioengineering. "This ancient period is an important piece of the story of our evolution too. We want to know better what the mammals were like then."

Author: Taylor Kubota | Source: Stanford University [April 20, 2017]

Genetic evidence suggests early mammals were nocturnal

Our earliest mammalian ancestors likely skulked through the dark, using their powerful night-time vision to find food and avoid reptilian pr...

Wednesday, April 19, 2017


The Cleveland Museum of Art and The Ministry of Cultural Heritage and Activities and Tourism of the Republic of Italy (Ministry) today announced that they have reached an agreement for the transfer of an early 1st century AD marble portrait head of Drusus Minor (Drusus Julius Caesar, 13 BC-AD 23) to the Republic of Italy.

Cleveland Museum of Art to transfer Roman sculpture of Drusus Minor to Italy
Head of Drusus Minor (13 BC-AD 23), probably after AD 23 and likely before AD 37. Roman, 1st cent. 
Marble; overall: h. 35 cm (13 3/4 in) [Credit: The Cleveland Museum of Art]
The sculpture, previously sold at a public auction in Paris in 2004, was acquired by CMA in 2012, after extensive research to confirm its ownership history. When the museum acquired the work, it was believed that the sculpture originally came from North Africa. When, more recently, CMA became aware of the fact that the sculpture may have been illicitly removed from a site near Naples towards the end of World War II, the museum promptly contacted the Ministry. Acting in cooperation with officials of the Ministry, and with the assistance of the Carabinieri for the Protection of Cultural Heritage, CMA was able to confirm the World War II events. As a result, CMA determined to transfer the sculpture to Italy

In 2008, the Cleveland Museum of Art entered into a cultural cooperation agreement with the Ministry that formed the basis for a new relationship between CMA and the Republic of Italy. That agreement also provided a framework for the museum to approach the Ministry and obtain the information necessary to allow the museum to decide to transfer the sculpture.

“We have had an excellent relationship with the Ministry for many years,” said William Griswold, CMA director. “When we became aware of facts that were inconsistent with our understanding of the provenance of the sculpture, contacting the Ministry directly was an easy decision in light of our many years of working with our Italian colleagues. We worked collaboratively with the Ministry first to determine the circumstances of the work’s removal and then to finalize the decision to transfer the work.”

"This return is the result of an important and fruitful cultural agreement and the full cooperation of CMA with the Italian authorities,” said the Minister of Cultural Heritage and Activities and of Tourism, Dario Franceschini. “Now we await the return of the work, which, once in Italy will be returned as soon as possible to Naples and its communities, from where it was removed."

Source: The Cleveland Museum of Art [April 19, 2017]

Cleveland Museum of Art to transfer Roman sculpture of Drusus Minor to Italy

The Cleveland Museum of Art and The Ministry of Cultural Heritage and Activities and Tourism of the Republic of Italy (Ministry) today annou...

Gunmen attacked security forces near St. Catherine's Monastery in Egypt's south Sinai on Tuesday, killing at least one police officer and injuring four others, the Health Ministry said, just a week after two deadly church bombings killed 45.

ISIS targets St. Catherine's Monastery in Sinai, Egypt
The Monastery of St. Catherine, near Mount Sinai in Egypt, where a policeman was killed and four others 
were wounded on Monday [Credit Pedro Costa Gomes/AFP/Getty Images]
Islamic State claimed responsibility for the attack on a police checkpoint about 800 meters from the entrance to the monastery, one of the world's most important Christian sites.

The attack comes just 10 days before Pope Francis is scheduled to visit Egypt and just over a week after two deadly suicide bombings on Christian churches, also claimed by Islamic State, plunged the country into mourning and marked one of the bloodiest days for the country's Christian minority in decades.

St . Catherine's, founded in the 6th century and located at the foot of Mount Sinai, is one of the oldest Christian monasteries in the world and a UNESCO world heritage site. It is part of the Eastern Orthodox church.

Egypt's Christian minority, which makes up about 10% of the country's 92 million people, has increasingly been targeted by Islamist militants, with three deadly church attacks in the span of four months.

In February, scores of Christian families and students fled North Sinai province after a spate of targeted killings.

A successful assault on St. Catherine's would be the latest challenge to President Abdel Fattah al-Sisi, who has pledged to protect the religious minority as part of his campaign against extremism.

Egypt has for years been battling an Islamist insurgency in the rugged and thinly populated northern Sinai, which gained pace after the military overthrew President Mohamed Mursi of the Muslim Brotherhood in 2013 following mass protests against his rule.

Attacks in Egypt's southern Sinai, a popular destination for tourists dotted with Red Sea resorts, are by contrast rare.

Security sources told Reuters that security had been put on high alert at tourist facilities across southern Sinai after the attack .

The attack in southern Sinai comes as Russia is expected to make a long-awaited decision on whether to restore flights to the Sharm el-Sheikh resort after a Russian airliner was downed in 2015, dealing a serious blow to the area's tourism industry, which relies heavily on Russian visitors.

Egypt's tourism industry, a crucial source of hard currency, has suffered in the years of turmoil that followed the overthrow of President Hosni Mubarak in 2011, as well as from the suspected bombing of the Russian plane, which killed all 224 on board.

Israel took the unusual step earlier this month of barring its citizens from crossing into the Sinai peninsula, saying the threat of attack s in the area inspired by Islamic State and other jihadi groups was high.

Author: Ali Abdelaty | Source: Reuters [April 19, 2017]

ISIS targets St. Catherine's Monastery in Sinai, Egypt

Gunmen attacked security forces near St. Catherine's Monastery in Egypt's south Sinai on Tuesday, killing at least one police office...

A prehistoric human skeleton, thought to be at least 5,000 years old, was uncovered during construction of a gallery for the Guar Kepah Neolithic site near Kepala Batas, on mainland Penang, on Monday.

5,000-year-old skeleton discovered in Malaysia
The prehistoric human skeleton was found at Guar Kepah Neolithic site on mainland Penang, near Kepala Batas 
[Credit: USM]
Universiti Sains Malaysia (USM) Global Archaeological Research Centre director Professor Datuk Dr Mokhtar Saidin said a skull, a femur bone and a rib cage were found beneath the floor of a house which had been recently flattened to make way for the gallery.

He said the bones were found 70cm underground as Public Works Department (PWD) backhoes were digging on Monday.

"This is an important discovery not only for us, but the state, and the nation as a whole. Digging works were immediately stopped following the discovery, and we took over to conduct the excavation.

"We have yet to conduct scientific studies, but we estimate it to be around 5,000 years old. More details, such as how the prehistoric people lived, what they ate and their burial patterns, will be released once we complete the studies," Dr Mokhtar told newsmen at Chief Minister Lim Guan Eng's office here, yesterday.

Mokhtar believes they could possibly find three skeletons at the site, but it would take them at least two weeks to excavate even the current findings.

USM's Global Archaeological Research Centre had been conducting excavation works and research at the site back in 2010, where prehistoric shells, pottery remnants, tool remnants and food remnants from the Neolithic period were found, documented and dated.

“With this latest discovery, our research is complete. We have the shells, the food, the hunting tools and now we have the skeleton. So, the gallery will be complete with all these on display,” Dr Mokhtar added.

Guar Kepah, the country's final remaining Stone Age site, features shell middens or mounds that date back more than five millennia.

According to a book by F. David Bulbeck, titled “The Perak Man and Prehistoric Skeletons of Malaysia”, a total of 37 skeletons were excavated from the site after British colonial officer G.W Earl first discovered the shell middens in 1860; dating placed the skeletons at between 4,000 and 5,000 years old.

Back in 2013, Mokhtar had said that the Neolithic period site at Guar Kepah, which is older than the ancient civilisation site of neighbouring Lembah Bujang, had the potential to be a major tourism draw.

The Neolithic era is considered to be the last period of the Stone Age, before the discovery of metal tools led humans into the Bronze Age.

He had said that the site was the only prehistoric evidence of marine adaptation by prehistoric humans living near the sea in Malaysia.

No new human remains were found beyond the 37 skeletons previously unearthed, and taken to the National Natuurhistorisch Museum in Leiden, Holland.

Meanwhile, Lim announced a RM20,000 allocation for further excavation works.

The Chief Minister also said that the state government is in talks to have the skeletons repatriated from Holland, to be placed in the new Guar Kepah gallery.

Author: Audrey Dermawan | Source: New Strait Times [April 19, 2017]

5,000 year old skeleton discovered in Malaysia

A prehistoric human skeleton, thought to be at least 5,000 years old, was uncovered during construction of a gallery for the Guar Kepah Neol...

 

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