Why don’t have turtles tail spikes like stegosaurs?


This 2017 music video is called Ankylosaurus | Dinosaur Songs | Pinkfong Songs for Children.

From North Carolina State University in the USA:

Why don’t turtles still have tail spikes?

Researchers explain why tail weaponry is rare

January 17, 2018

Summary: In a study covering 300 million years of evolutionary history, researchers have found four necessary components to tail weapon development: size, armor, herbivory and thoracic stiffness.

We’re all familiar with those awesome armored giants of the Jurassic and Cretaceous periods — Stegosaurus and Ankylosaurus — and their amazing, weaponized tails. But why aren’t similar weaponized tails found in animals living today? In a study covering 300 million years of evolutionary history, researchers from North Carolina State University and the North Carolina Museum of Natural Sciences found four necessary components to tail weapon development: size, armor, herbivory and thoracic stiffness.

“Weapons like tail clubs and bony spikes are found only in a few extinct animals — such as ankylosaurs, glyptodonts (large extinct armadillos) and in some ancient turtle species,” says Victoria Arbour, former postdoctoral student at NC State, current postdoctoral fellow at the Royal Ontario Museum and corresponding author of a paper describing the research. “These same weapons just don’t occur in modern-day animals, and we wanted to know why they were so rare even in the fossil record.”

Study co-author Lindsay Zanno, professor of biological sciences at NC State and head of paleontology at the NC Museum of Natural Sciences, agrees, “We kicked off this study with a simple observation: most animal weapons used for combat are located on the most critical part of the body for survival, the head, as opposed to more expendable ones such as the tail. Why, we asked, wasn’t evolution producing more animals with weaponized tails, when this would seem to be far less dangerous?”

To answer this question, Arbour and Zanno looked at a data set of 286 amniote species, both living and extinct, to see if there were patterns that pointed to the evolution of three specific types of tail weapons: bony spikes, a stiff tail or a bony knob at the tip of the tail. Amniotes refer to backboned, four-legged reptiles and mammals, as well as birds.

In the case of bony tail weaponry, the researchers found the animals had four things in common. First, they were usually large, weighing over 200 pounds (or 100 kilograms) — about the weight of the glyptodonts that used to roam South America or a living mountain goat — or were over three feet (a meter) long.

Second, armor was key. Ancient turtles, armadillos and armored dinosaurs were covered in some sort of hard carapace or bony plated armor. Thoracic stiffness — referring to a body that doesn’t bend side to side easily, perhaps so that it could easily counteract the forces needed to swing a large clubbed or spiked tail — was also important. Finally, every animal in the fossil record that developed elaborate tail weaponry was an herbivore, or vegetarian.

“It’s rare for large herbivores to have lots of bony armor to begin with,” Arbour says, “and even rarer to see armored species with elaborate head or tail ornamentation because of the energy cost to the animal. The evolution of tail weaponry in Ankylosaurus and Stegosaurus required a ‘perfect storm’ of traits that aren’t seen in living animals, and this unique combination explains why tail weaponry is rare even in the fossil record.”

Zanno continues, “This study is an elegant example of how the fossil record can be used to better understand the world around us today.”

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Elephants in Borneo, why?


This video says about itself:

Saving the Borneo Elephant (full documentary) HD

The Bornean Elephant is a subspecies of the Asian Elephant, physically and behaviourally different from the elephants of mainland Asia. Known locally and commonly as ‘Bornean Pygmy elephants’, they are about a fifth smaller than mainland Indian elephants but similar in size to populations of Sumatra and the Malaysian Peninsula. They are generally more rotund in appearance with shorter trunks and a smaller rounder face, which makes their ears appear larger. They also have a long tail, which in some individuals reaches all the way down to the ground . Only some males display tusks, which are shorter and straighter than in the mainland elephants.

From the Instituto Gulbenkian de Ciencia:

New light on the mysterious origin of Bornean elephants

January 17, 2018

How did Borneo get its elephant? This could be just another of Rudyard Kipling’s just so stories. The Bornean elephant is a subspecies of Asian Elephants that only exist in a small region of Borneo. Their presence on this southeastern Asian island has been a mystery. Now, in a study published in Scientific Reports, a research team led by Lounès Chikhi from Instituto Gulbenkian de Ciência (IGC, Portugal) and CNRS, Université Paul Sabatier (France), and Benoit Goossens, from Cardiff University (Wales), and Sabah Wildlife Department (Malaysia), found that elephants might have arrived on Borneo at a time of the last land bridge between the Sunda Islands in Southeast Asia.

Until recently, two opposing theories have been under debate to explain the origin of Bornean elephants: they could have been recently introduced by humans, maybe 300 years ago, or they could have diverged from Asian elephants a long time ago. Indeed, there are historic records reporting that, in the 17th century, neighbour Sultans offered elephants as gifts to the Bornean Sultan. Current elephants would thus be non-native elephants that turned feral. On the other hand, about 15 years ago a genetic study showed that the DNA of Bornean elephants was very different from that of other Asian elephants, suggesting a very ancient separation, on the order of 300,000 years ago. However, no elephant fossils have yet been discovered in Borneo, even though fossils from other large mammals such as orang-utans have been found.

To shed light on the mystery of Bornean elephant’s origin, Chikhi and Goossens’ team used genetic data analysis and computational modelling to study the past demographic history of these animals. It is very difficult to track ancient demographic history of animals, even more when there are no fossil records to guide the work. “What we did was to create computational models for different scenarios that might have happened. Then, we compared the results from these models with the existing genetic data, and used statistical techniques to identify the scenario that best explained the current genetic diversity of the elephant population in Borneo”, explains Lounès Chikhi.

“Our results suggest that the most likely scenario to have occurred is a natural colonization of Borneo around 11,400 to 18,300 years ago. This period corresponds to a time when the sea levels were very low and elephants could migrate between the Sunda Islands, a Southeastern Asia archipelago to which Borneo belongs. We cannot exclude more complex scenarios, but a historical human introduction seems very improbable, and so does a very ancient arrival”, adds Reeta Sharma, researcher at the IGC and first co-author of the paper.

With less than 2000 individuals surviving today in an increasingly fragmented environment, and with regular news of poisoned or killed Bornean elephants, the future is grim for this endangered species. “Its very limited geographic distribution and reduced genetic diversity compromise the future of the population. Understanding their origins and past demography will be useful for the development of a long-term conservation strategy, especially at the time we, Sabah Wildlife Department, and partners are drafting a new 10-year State Action Plan for the Bornean elephant”, said Goossens. The researcher notes “in the light of the recent killings of elephants in the state for ivory trade and during conflicts, Sabahans must realise that it is their natural patrimony that is targeted, they need to stand for their wildlife and condemn those who kill those magnificent creatures. We should take pride of our wildlife, elephants are part of Sabah’s patrimony and we cannot afford losing more animals.”

How Alaskan bears help plants


This video about Alaska is called The Land of Giant Bears.

From Oregon State University in the USA:

Great scat! Bears — not birds — are the chief seed dispersers in Alaska

January 16, 2018

It’s a story of bears, birds and berries.

In southeastern Alaska, brown and black bears are plentiful because of salmon. Their abundance also means they are the primary seed dispersers of berry-producing shrubs, according to an Oregon State University study.

The OSU team used motion-triggered cameras to record bears, birds and small mammals eating red berries of devil’s club, and retrieved DNA in saliva left on berry stalks to identify the species and sex of the bears. Researchers found that bears, while foraging, can disperse through their scat about 200,000 devil’s club seeds per square kilometer per hour. Rodents then scatter and hoard those seeds, much like squirrels hoard acorns.

The study was published today in the journal Ecosphere.

In most ecosystems, birds generally are thought of as chief dispersers of seeds in berries, said Taal Levi, an ecologist in OSU’s College of Agricultural Sciences and co-author on the study. The researchers found that birds accounted for only a small fraction of seed dispersal.

This is the first instance of a temperate plant being primarily dispersed by mammals through their gut, and suggests that bears may influence plant composition in the Pacific Northwest.

It was well-known that bears were dispersing seeds through their scat, Levi said, but it was not known that they were dispersing more seeds than birds, or the relative contribution of brown and black bears to seed dispersal, or whether the two species bears were eating berries at different times of the year.

“Devil’s club is extremely abundant in northern southeast Alaska, so it didn’t seem plausible that birds were dispersing all this fruit”, Levi said. “Bears are essentially like farmers. By planting seeds everywhere, they promote a vegetation community that feeds them.”

The researchers found that in the study area along the Chilkat and Klehini rivers in southeastern Alaska, brown bears dispersed the most seeds, particularly before salmon became widely available. They also found that after the brown bears switched from eating berries to salmon later in the season, black bears moved in and took over the role as principal seed dispersers. Black bears are subordinate to brown bears and avoid them.

The fruit on a devil’s club stalk is clustered into a cone containing berries. The researchers observed through the camera recordings that brown bears can swallow an estimated 350 to 400 berries in a single mouthful. Birds, on the other hand, consumed on average 76 berries per plant that they visited.

“That’s pretty remarkable,” Levi said. “When birds visit these shrubs, they take a few berries and fly off. They don’t eradicate the cones like a bear.”

Laurie Harrer, Levi’s co-author, swabbed devil’s club to retrieve environmental DNA from residual saliva left by animals and birds that ate the berries. Harrer, a master’s student in OSU’s Department of Fisheries and Wildlife, analyzed the samples to determine that female brown bears ate more berries than male brown bears, female black bears ate more than male black bears and brown bears ate more than black bears.

Brown bears, also known as grizzlies, are extinct in Oregon and California and are nearly extinct in Washington.

“The indirect effect of salmon is that they support abundant bear populations that then disperse a lot of fruit”, Levi said. “We’ve lost the salmon-bear ecosystem that once dominated the Pacific Coast. That has implications for the plant community. These seed dispersal pathways through brown bears are all but eliminated. The degree to which black bears can fulfill that role is not clear.”

Marsupial fossil discovery in Australia


This 2016 video is called Extinct and Extant Australian Species.

From Palaeontologia Electronica:

Miminipossum notioplanetes, a Miocene forest-dwelling phalangeridan (Marsupialia; Diprotodontia) from northern and central Australia

ABSTRACT

Miminipossum notioplanetes represents a new Early/Middle Miocene family (Miminipossumidae) of phalangeridan possums recovered from the Two Trees Local Fauna from the Riversleigh World Heritage area in northwestern Queensland and the Kutjamarpu Local Fauna of the Tirari Desert in northern South Australia. Because of widespread convergence in key features of P3 and M1 among phalangeridan families, the interfamilial relationships of Miminipossumidae are uncertain. The age of the Kutjamarpu Local Fauna has been in doubt with estimates ranging from Late Oligocene to Middle Miocene. The new taxon raises to 15 the number of taxa in the Kutjamarpu Local Fauna that are shared with both Riversleigh’s Faunal Zone B (Early Miocene) and Riversleigh’s Faunal Zone C (Middle Miocene) assemblages.

Although there is relatively little biocorrelative support for the estimate of a Late Oligocene age, doubt remains about whether the age is more likely to be Early or Middle Miocene. In terms of palaeoenvironmental implications, because both Riversleigh’s Early and Middle Mio-cene assemblages have been concluded to have accumulated in temperate, wet, species-rich lowland forests, the same or similar Early/Middle Miocene palaeoenvironments may well have extended into central Australia at the time when the Kutjamarpu assemblage was accumulating.

British Conservative defeat on fox-hunting


This is a red fox video.

By Peter Frost in Britain:

Friday, January 12, 2018 – 00:27

Wildlife: Reynard can breathe easy now – well, almost

Prime Minister Theresa May’s decision not to allow Parliament a vote on allowing fox-hunting, despite manifesto promises, is one that PETER FROST is prepared to applaud unreservedly

PRIME MINISTER Theresa May has confirmed ditching plans that would have allowed a free vote in Parliament to end the legal ban on fox-hunting.

She did this even before starting to rearrange the deckchairs for the reshuffle of her fast-sinking cabinet.

This U-turn has angered some Tory Party members and supporters in its rural heartlands.

When the Conservative Party last published its membership figures in 2013, the number recorded was 149,800. Experts reckon the membership today is nearer half that and is declining particularly fast in country villages and towns.

That is why the Tories have had to make undercover deals with pro-hunting groups like the Countryside Alliance which thought it had a contract with May, during the last general election, to get the countryside-based Tory vote out in exchange for May promising a free fox-hunting vote.

May says she has always supported legalising fox-hunting. Her 2017 manifesto promised: “We will grant a free vote, on a government Bill in government time, to give Parliament the opportunity to decide the future of the Hunting Act.” That pledge has now gone the way of so many of her promised policies.

The reason for the volte-face is that May’s advisers pointed out that, with every new poll on fox-hunting, fewer and fewer people are in favour of the bloody sport.

But there are some who still support hunting. Up to 300 hunts turned out on Boxing Day, traditionally hunting’s biggest day, at the end of last month.

As usual and despite public opinion and the law banning the hunting of foxes being over a dozen years old, posh country folk, horses and hounds gathered on the busiest day of the year for this antiquated and barbaric custom.

As at every Boxing Day since the law was passed by a Labour government in 2005, foxes were killed illegally by the hunters and their savage trained packs of killer hounds.

In many of those locations the hunts claimed they were carrying out legal trail-hunting, following an animal-based scent drag, often using fox urine.

In fact this was more often used as a cover for actual traditional blood-sport hunting. The deception fooled nobody.

Many people accuse these hunts of not obeying the law and provide video evidence showing foxes meeting a bloody death.

One group opposed to hunting are the Hunt Saboteurs, a non-violent direct action group that attempts to document and prevent the killing of animals.

Other reputable organisations, such as the International Fund for Animal Welfare, say that no genuine trail hunting was witnessed at 98 per cent of the hunts observed in 2015, with scent trails actually laid at only eight of the 478 hunts monitored.

Even the Countryside Alliance (CA), which supports hunting and lobbies for repeal of the Hunting Act, admits that at least 27 convictions in relation to registered hunts have been recorded since 2005.

It claims the majority of hunts use an ethically sourced, animal-based scent, but Freedom of Information Act requests made to the Animal and Plant Health Agency revealed they have issued just one import authorisation licence for fox urine or any other related animal by-product since 2014.

This is simply nowhere near enough to allow the scale of trail hunting that the hunting industry claims goes on.

Although fox-hunting with hounds was supposed to have ended in 2005, the law makes the burden of proof exceptionally high and the huntsman/woman has to be judged to have deliberately killed a fox. This usually requires good video evidence for a prosecution to stand a chance of success in court.

Numerous successful prosecutions are brought each year but still the bloody so-called-sport continues.

Claims by the hunting fraternity, when they were campaigning before the law was passed, that hunts would close and be forced to put down all their dogs have come to nothing. The predicted loss of jobs by hunt servants simply never happened.

At the last election, Theresa May forced the issue of a free vote on the Hunting Act into the manifesto against the advice of senior cabinet members, telling a campaign event she has “always been in favour of fox-hunting.”

In reality the vast majority of public opinion wants to keep the ban and this includes many countryside dwellers as well as urban-based folk.

One of the more surprising groups opposed to hunting is Blue Fox, a large group of Tory MPs, mainly women, totally opposed to blood sports in the countryside. They have welcomed May’s U-turn.

Labour leader and prime minister in waiting Jeremy Corbyn has consistently branded fox-hunting a barbarity and pledged to condemn blood sports to the dustbin of history forever when he comes to power.

Corbyn, who grew up in rural Shropshire, made his first political speech at school aged just 15. He spoke in favour of banning fox, stag and otter-hunting as well as badger-baiting and hare-coursing.

Unlike May, Corbyn has never deviated from this anti-hunting position.

Sounds like Reynard and all the little foxes have a better future to look forward to than does May.

Big fossil bat discovery in New Zealand


This video says about itself:

Fossils Reveal Giant New Species of Burrowing Bat: Vulcanops jennyworthyae

11 January 2018

Paleontologists say they’ve found the fossilized remains of a new genus and species of bat that lived in New Zealand between 19 and 16 million years ago (Early Miocene epoch).

From daily The Independent in Britain:

Giant extinct burrowing bat unearthed in New Zealand by palaeontologists

Discovery highlights the diversity of life that has been lost from the island nation

Josh Gabbatiss, Science Correspondent

Thursday 11 January 2018 18:15 GMT

Palaeontologists have discovered teeth and bones belonging to an ancient species of burrowing bat.

The species, named Vulcanops jennyworthyae, inhabited New Zealand around 16 million years ago.

Burrowing bats are a unique group of mammals only found in New Zealand.

These animals not only fly, but crawl along the ground too, and are equipped with specialised claws that enable them to do so.

Vulcanops is the biggest burrowing bat ever found – although it still only weighed around 40 grams.

The finding was described in the journal Scientific Reports.

“Burrowing bats are more closely related to bats living in South America than to others in the south-west Pacific,” said Professor Sue Hand, the first author of the study describing the new species, and a palaeontologist at the University of New South Wales.

Specifically, Prof Hand said burrowing bats such as Vulcanops are related to vampire bats.

However, unlike its blood-feeding cousins, the teeth of this new species suggest it consumed plant material as well as small creatures.

The scientists said the discovery served as a reminder of the diversity of life that has been lost from New Zealand.

“These bats, along with land turtles and crocodiles, show that major groups of animals have been lost from New Zealand”, said study co-author Professor Paul Scofield, of Canterbury Museum.

“They show that the iconic survivors of this lost fauna – the tuataras, moas, kiwi, acanthisittid wrens, and leiopelmatid frogs – evolved in a far more complex community that hitherto thought.”

Many bats used to inhabit New Zealand, but climate fluctuations are thought to have led to the ultimate demise of all but two species, which still survive today.

While the nation is still home to a diverse array of bird species, the two remaining bats are the only mammals to still inhabit the island that were not introduced by humans.