Dinosaur extinction and bird evolution


This American Museum of Natural History video from the USA says about itself:

18 March 2016

This spellbinding animation from the Museum’s new exhibition “Dinosaurs Among Us” traces the evolutionary transition from dinosaurs to birds.

Based on recent scientific research that examines fossils using new technologies, the transformation story unfolds as low-polygonal silhouettes of dinosaurs morph from ground-dwelling animals into flight-capable birds. The mass extinction that erased most dinosaurs 65 million years ago left a few bird lineages unscathed. Within only 15 million years all of our familiar bird groups were flourishing. These extraordinary living dinosaurs provide a vivid link to the ancient past. The Museum’s new exhibition, “Dinosaurs Among Us,” explores the continuities between living dinosaurs—birds—and their extinct ancestors, showcasing remarkable new evidence for what scientists now call one of the best-documented evolutionary transitions in the history of life.

From Cornell University in the USA:

Dino-killing asteroid’s impact on bird evolution

September 21, 2017

Human activities could change the pace of evolution, similar to what occurred 66 million years ago when a giant asteroid wiped out the dinosaurs, leaving modern birds as their only descendants. That’s one conclusion drawn by the authors of a new study published in Systematic Biology.

Cornell University Ph.D. candidate Jacob Berv and University of Bath Prize Fellow Daniel Field suggest that the meteor-induced mass extinction (a.k.a. the K-Pg event) led to an acceleration in the rate of genetic evolution among its avian survivors. These survivors may have been much smaller than their pre-extinction relatives.

“There is good evidence that size reductions after mass extinctions may have occurred in many groups of organisms,” says Berv. “All of the new evidence we have reviewed is also consistent with a Lilliput Effect affecting birds across the K-Pg mass extinction.” Paleontologists have dubbed this phenomenon the “Lilliput Effect” — a nod to the classic tale Gulliver’s Travels.

“Smaller birds tend to have faster metabolic rates and shorter generation times,” Field explains. “Our hypothesis is that these important biological characters, which affect the rate of DNA evolution, may have been influenced by the K-Pg event.”

The researchers jumped into this line of inquiry because of the long-running “rocks and clocks” debate. Different studies often report substantial discrepancies between age estimates for groups of organisms implied by the fossil record and estimates generated by molecular clocks. Molecular clocks use the rate at which DNA sequences change to estimate how long ago new species arose, assuming a relatively steady rate of genetic evolution. But if the K-Pg extinction caused avian molecular clocks to temporarily speed up, Berv and Field say this could explain at least some of the mismatch. “Size reductions across the K-Pg extinction would be predicted to do exactly that,” says Berv.

“The bottom line is that, by speeding up avian genetic evolution, the K-Pg mass extinction may have temporarily altered the rate of the avian molecular clock,” says Field. “Similar processes may have influenced the evolution of many groups across this extinction event, like plants, mammals, and other forms of life.”

The authors suggest that human activity may even be driving a similar Lilliput-like pattern in the modern world, as more and more large animals go extinct because of hunting, habitat destruction, and climate change.

“Right now, the planet’s large animals are being decimated — the big cats, elephants, rhinos, and whales,” notes Berv. “We need to start thinking about conservation not just in terms of functional biodiversity loss, but about how our actions will affect the future of evolution itself.”

The Chicxulub asteroid impact that wiped out the dinosaurs likely released far more climate-altering sulfur gas into the atmosphere than originally thought, according to new research: here.

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Trump threatens nuclear war, reactions


This video from the USA says about itself:

Economist Jeff Sachs: Americans Who Don’t Want War with Iran Must Speak Out Now

21 September 2017

President Trump’s comments at the United Nations General Assembly urging the withdrawal from the Iran nuclear deal sounded familiar to our guest, Jeffrey Sachs. “The last time we had this kind of rhetoric was George W. Bush with the axis of evil,” Sachs said. “It was immediately followed by the Iraq War, which was the most disastrous single step of American military action and ‘diplomacy,’ or anti-diplomacy, in modern times. So this is a setup, again, for war, for conflict. And it is extraordinarily ignorant and dangerous. Iran is in compliance with the agreement that was reached.”

Fears of nuclear war grow after Trump’s threat to annihilate North Korea: here.

Just two days after using the UN General Assembly as platform for a fascistic tirade, threatening to “totally destroy” North Korea, US President Donald Trump yesterday unveiled new sanctions threatening punitive penalties on countries and companies accused of having trade-related financial relations with Pyongyang: here.

The US corporate media has responded with what amounts to a collective yawn to the fascistic tirade by President Donald Trump at the United Nations General Assembly on Tuesday. Trump’s speech, delivered to an international body with institutional roots in the Nuremberg trials of the leaders of Germany’s Third Reich and ostensibly dedicated to eliminating the scourge of war, was that of an unabashed war criminal: here.

The bulk of the Australian political and media establishment has endorsed—either explicitly or implicitly by their silence—the fascistic rant delivered by US President Donald Trump to the UN General Assembly on Tuesday: here.

US initiates plan to blow-up Iran nuclear deal: here.

Bernie Sanders launches passionate defence of Iran Deal and attacks Trump’s threat to scrap it. ‘We must protect this agreement,’ Mr Sanders said: here.

Blue jays survive Hurricane Irma in Florida


This video from the USA says about itself:

18 September 2017

The Backyard Blue Jays survived Hurricane Irma which was a category one when it passed the Backyard. A lot of trees de-leafed and blown down in the conservation area, but the birds and squirrels know how to survive. More on that later. But that’s not to say they weren’t hungry and happy for a friendly peanut when I got back home! Good to see them again.

Irma damages Sint Maarten island wildlife: here.

Hurricane Maria, Puerto Rico and further


This video says about itself:

Hurricane Maria Leaves Puerto Rico Completely Without Power

20 September 2017

CBS Miami’s Eliott Rodriguez reports.

Maria regains strength as it pulls away from Puerto Rico, approaches Dominican Republic, Turks and Caicos: here.

By Rafael Azul:

Hurricane Maria devastates Puerto Rico

21 September 2017

Hurricane María, which hit Puerto Rico Wednesday, has left the US territory in ruins. With much of the electrical, cell phone and road system severely damaged, the full scope of the devastation, including fatalities and serious injuries, is still not known, but losses to homes, businesses and critical infrastructure are expected to be massive.

María cut a 120-mile diagonal swath across the country. The leading edge of the storm began affecting southeastern Puerto Rico Tuesday night. Its eye entered the town of Yabucoa at 6 a.m. Eastern Time, and exited at noon on the northern coast between the cities of Arecibo and Barceloneta, west of the capital city of San Juan.

Governor Ricardo Rosselló, who declared an emergency and imposed a 6pm to 6am curfew, gave an initial account of the situation at 10 a.m. Wednesday, saying there had been “severe damage to infrastructure and great devastation.” He also warned of the danger of floods and mudslides which will put “lives at risk” as the tail end of the hurricane continued to pummel Puerto Rico a few hours longer.

The governor called on US President Donald Trump to declare Puerto Rico a “disaster area,” up from “emergency area,” which would allow the allocation of unlimited federal funds for Puerto Rico, as opposed to a maximum of $5 million provided to emergency areas.

Conditions in Puerto after Hurricane Maria hit [Credit: @Jennifer2012]

This is a pittance for the island, which declared bankruptcy prior to Hurricanes Maria and Irma. Puerto Rico is saddled with a debt of $74 billion in bonds and $50 billion in supposedly unfunded pension obligations. Its electrical utility, AEE (Autoridad de Energía Eléctrica, or PREPA in English), which defaulted on its $9 billion debt in July, is also in ruin.

Initial reports said that all 3.4 million residents were without power after the hurricane, while wide swaths of the island are without clean water. Many roads are impassable. Having lost the ability to borrow, Puerto Rico is now desperately in need. Other than remittances from Puerto Ricans living in the US and elsewhere, the funds that do come in will undoubtedly include punishing financial obligations to Wall Street.

Abner Gomez, head of the Puerto Rican Emergency and Disaster Management Agency (AEMEAD) painted a bleak scene of hurricane devastation. “We are going to find that our island has been destroyed. We are receiving information that leaves no room for hope. This [storm] system has destroyed everything on its path.”

María did not spare San Juan, including working class and middle class high-rise apartment buildings that suffered broken windows and flooded rooms. Residents described to the local media torrents of water going down stairs from flooded apartments. Imy Rigaus, 53, described having to seek refuge in the hallway of her apartment. “Water cascaded down the stairs, and entered the apartments, and we are trapped in the hallways,” she said.

In the Roberto Clemente stadium, which was designated as a shelter, rain cascaded through a wind-damaged roof, forcing evacuees to hide beneath the stands. “One of the guards told me that the roof is about to collapse,” said Suzette Vega, an evacuee. “I looked up and the roof was waving around like a piece of paper. I asked, ‘Is it made out of cardboard?’ ‘No,’ they told me, ‘it is cement.’”

Carmen Yulin Cruz, San Juan’s mayor, informed its citizens that electricity would be out for a long time. “The devastation is all around us,” declared Cruz, “our life as we knew it, has changed.”

The Madrid daily El País paints a picture of utter devastation, torrential rains, floods, breached dams, six-foot storm surges, trees flying through the air, and windows exploding. Hardest hit was the central region, but no place in the island, no town, no square meter, was left unaffected.

The San Juan daily El Nuevo Día gave further details. Many residential areas have been almost totally destroyed, including hospitals, where patients were sheltered in hallways, as hurricane winds of more than 160 miles per hour smashed windows. At least one of the government shelters was left “in pieces,” the web site reported.

Late arrivers to the shelters describe having to fight wind gusts that made the sheets of rain feel like “whips,” while trying to avoid all manner of flying objects.

Others described equally harrowing scenes of roofs being torn off. Half of Puerto Rico’s citizens live under the poverty line, many of them in precarious structures with zinc roofs.

Despite government evacuation orders, the majority of residents were not able to find their way to government shelters. Nydia Pérez, who lives in San Juan, told El País, “In my house a window exploded and a door was torn off. The wind and rain damaged my living room. Across the street, the entire roof blew off.”

Benjamin Morales said via Facebook, “Mobile service comes and goes; winds are still extremely strong; there is a lot of rain. All kinds of damage is being reported … electric service is dead, as had been expected. My house has security windows rated at 300 kilometers (180 miles); at times I thought that they would be ripped off. Everybody at the radio station feels that nothing like this has ever happened before.”

With wireless communications gone, together with many landlines, Puerto Ricans from Florida, Chicago, New York, and other US cities have been flooding San Juan radio stations in an attempt to connect with relatives. Many ask for help for relatives that suffer from medical conditions, such as diabetes.

The Financial Oversight Board that rules over Puerto Rico on behalf of Wall Street banks and hedge funds, has yet to pronounce itself about Hurricane María’s destruction, other than some pro forma remarks from its chairman, José Carrión, who declared that the board is “extremely concerned.”

This woman chartered a jet to save 300 animals on the Virgin Islands in the wake of Hurricane Irma.

Intense storms provide the first test of powerful new hurricane forecast tools. Instruments are slated to improve predictions of path and intensity. By Carolyn Gramling, 8:07am, September 21, 2017.

European birds update


This video from Ireland says about itself:

Common garden birds 16 05 2013

For bird lovers. Featuring European Robin, House Sparrow, Blue Tit, Great Tit, Starling and Jackdaw.

From BirdLife:

The Bird Bulletin – Vol. 13

By Gui-Xi Young

The summer is over, the kids are back in school and our Bird Bulletin is back bringing you beak-sized updates from across Europe & Central Asia.

TRIAL & ERROR – right now the battle over Białowieża is being fought in the European Court of Justice (ECJ). As Poland continues to defy the ECJ’s injunction over its illegal logging activities, the European Commission has told the court that the desecration of Europe’s last ancient forest must warrant financial penalties. BirdLife now calls on the Commission to demand fines that are severe enough to show that crime doesn’t pay.

Follow #Białowieża and #SaveBiałowieża  to watch the story unfold and sign WeMove’s Defend the Forest petition.

A ‘Tern’ for the better – a 12 mile stretch of England’s North Sea coastline has just been designated a Marine ‘Special Protection Area’ (SPA), ensuring greater protection for some 200,000 seabirds. This area of Northumberland is the most important site in the UK for Arctic, Common and Roseate terns. Read more…

PAINT IT BLACK – Iceland’s environment minister has signed a regulation banning the shooting of Black Guillemots in the country. This milestone was achieved thanks to effective cooperation between BirdLife’s Icelandic partner Fuglavernd, the Icelandic Ecological Society (Vistfræðifélag Íslands) and the Icelandic Shooting Association (Skotvís). Read more…

Migration over Malta – with thousands of birds passing through Malta on their autumn migration to Africa, birdwatchers on the islands have been sending amazing footage to BirdLife Malta. Watch the footage here…

EAT, PREY, LOVE – Help us save Europe’s magnificent vulture species from the threat of diclofenac, the veterinary drug that wiped out 99% of vultures on the Indian subcontinent in the 1990s. Support our BanVetDiclofenac campaign!

Well that’s all for today’s ‘Bird Bulletin’ – tune in next week for more cheeps, chirps and chatter.

Bye bye birdies!

Some herbivorous dinosaurs really omnivorous?


This 2012 video from the USA says about itself:

Maiasaura: Learn About Dinosaurs with World Book’s Professor Nick

Maiasaura was a large plant-eating dinosaur noted for its nesting behavior. Its name means good mother lizard, though dinosaurs were not lizards. Evidence suggests that its hatchlings were completely dependent on their parents for food and protection. Maiasaura lived about 75 to 80 million years ago in the area of what is now Montana. It belonged to a group known as duckbilled dinosaurs or hadrosaurids. These dinosaurs ate plants using a beak that somewhat resembled a duck’s bill.

By Carolyn Gramling, 9:00am, September 21, 2017:

Shhhh! Some plant-eating dinos snacked on crunchy critters

Crustacean shells discovered in fossilized poop reveal diet secrets of ancient herbivores

Some dinosaurs liked to cheat on their vegetarian diet.

Based on the shape of their teeth and jaws, large plant-eating dinosaurs are generally thought to have been exclusively herbivorous. But for one group of dinosaurs, roughly 75-million-year-old poop tells another story. Their fossilized droppings, or coprolites, contained tiny fragments of mollusk and other crustacean

Mollusks and crustaceans are two different groups.

shells along with an abundance of rotten wood, researchers report September 21 in Scientific Reports. Eating the crustaceans as well as the wood might have given the dinosaurs an extra dose of nutrients during breeding season to help form eggs and nourish the embryos.

“Living herd animals do occasionally turn carnivore to fulfill a particular nutritional need,” says vertebrate paleontologist Paul Barrett of the Natural History Museum in London. “Sheep and cows are known to eat carcasses or bone when they have a deficiency in a mineral such as phosphorus or calcium, or if they’re pregnant or ill.” But the discovery that some plant-eating dinos also ate crustaceans is the first example of this behavior in an extinct herbivore, says Barrett, who was not involved in the new study.

Ten years ago, paleoecologist Karen Chin of the University of Colorado Boulder described finding large pieces of rotted wood in dino dung. The coprolites were within a layer of rock in Montana, known as the Two Medicine Formation, dating to between 80 million and 74 million years ago. That layer also contained numerous fossils of Maiasaura, a type of large, herbivorous duck-billed dinosaur, or hadrosaur (SN: 8/9/14, p. 20).

Chin wondered whether the wood itself was the dino’s real dietary target. “The coprolites in Montana were associated with the nesting grounds of the Maiasaura,” she says. “I suspected that the dinosaurs were after insects in the wood. But I never found any insects in the coprolites there.”

Her hunch wasn’t too far off. Now she’s found evidence of some kind of crustaceans in dino poop. The new evidence comes from an 860-meter-thick layer of rock in Utah known as the Kaiparowits Formation, which dates to between 76.1 million and 74 million years ago. Ten of the 15 coprolites that Chin and her team examined contained tiny fragments of shell that were scattered throughout the dung. They were too small to identify by species, and may have been crabs, insects or some other type of shelled animal, Chin says. Based on the scattering of shell fragments, the animals were certainly eaten along with the wood rather than being later visitors to the dung heap.

Since bones from hadrosaurs are especially abundant in the Kaiparowits Formation, Chin suspects those kinds of dinos deposited the dung. Other large herbivores, such as three-horned ceratopsians and armored ankylosaurs, also roamed the area (SN: 6/24/17, p. 4).

The crustacean diet cheat may have been a seasonal event, related perhaps to breeding to obtain extra nutrients, Chin and colleagues say.

But how often — or why — the dinosaurs ate the shelled critters is hard to prove from the fossil dung alone, Barrett says. Herbivore coprolites are rare in the fossil record because a diet of leaves and other green plant material doesn’t leave a lot of hard material to preserve (unlike bones in carnivore dung). Coprolites with crustaceans, on the other hand, are more likely to get fossilized — and that preferential preservation might make it appear that this behavior was more frequent than it actually was. “These kinds of things give neat snapshots of specific behaviors that those animals are doing at any one time,” he adds. “But it’s difficult to build that into a bigger picture.”