Kangaroos need their tails, new research


This video is called Kangaroo Walking.

From Wildlife Extra:

A fifth leg helps kangaroos walk

Red kangaroos may be one of nature’s best hoppers, able to lope along at speeds of up to 12 miles an hour on their hind legs, while their two front legs seem to dangle obsolete.

But when they are grazing or walking, which is actually most of the time, not only do they need those front legs but also their tail, which a new study has dubbed their fifth limb.

“We found that when a kangaroo is walking, it uses its tail just like a leg,” said study author Associate Professor Maxwell Donelan of Simon Fraser University in Canada.

“They use it to support, propel and power their motion. In fact, they perform as much mechanical work with their tails as we do with one of our legs.”

When grazing on grass red kangaroos, which are the largest of the kangaroo species in Australia, move both hind feet forward “paired limb” style, while working their tails and front limbs together to support and move their bodies.

“They appear to be awkward and ungainly walkers when one watches them moseying around in their mobs looking for something to eat,” said co-author Associate Professor Rodger Kram.

“But it turns out it is not really that awkward, just weird. We went into this thinking the tail was primarily used like a strut, a balancing pole, or a one-legged milking stool.

“What we didn’t expect to find was how much power the tails of the kangaroos were producing.

“It was pretty darn surprising.”

However when the roos are in their faster, hopping gait the tail returns to being a dynamic, springy counterbalance.

Echidna hatching from egg, video


This video says about itself:

The echidna is quite unique as it’s a mammal that lays eggs rather than giving birth to live young. This clip is an excerpt from our 1974 production, “Comparative biology of lactation”. A young echidna is called a puggle.

Video transcript available here.

From Smithsonian magazine in the USA:

Watch This Adorable Mammal Hatch From an Egg

A 1974 nature video shows a spiny anteater hatching

By Mary Beth Griggs

Via one of our favorite video blogs, The Kids Should See This, check out this incredible video of an echidna—also known as a spiny anteater—hatching from an egg. Echidnas live in Australia and on the island of New Guinea, and they are some of the only egg laying mammals in existence, along with the fantastically weird platypus.

Australia’s Commonwealth Scientific and Industrial Research Organization, or CSIRO, made this video in 1974. On the organization’s YouTube page, there are many more examples of wonderfully weird old example[s] of animal videos, including vintage favorites like the echidna hatching or a 1965 educational video about the birth of a red kangaroo. (That last one shows the actual birth of a live kangaroo and is not for the faint of heart.)

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Australian marsupial species discovered, killing itself by sex


This video from Australia is called Queensland: The suicidal mating routine of the male marsupial antechinus.

From Reuters:

Scientists Discover New Marsupial That Has Sex Until It Dies

02/21/2014 10:59 am EST

SYDNEY, Feb 20 – Australian scientists have discovered a new species of marsupial, about the size of a mouse, which conduct marathon mating sessions that often prove fatal for the male.

The Black-Tailed Antechinus has been found in the high-altitude, wet areas of far southeast Queensland and northeast New South Wales.

It is identifiable by a very shaggy coat and an orangey-brown coloured rump which ends with a black tail.

But it’s their strenuous mating sessions, which can last for to 14 hours, with both the males and females romping from mate to mate, that is most striking about the animals.

“It’s frenetic, there’s no courtship, the males will just grab the females and both will mate promiscuously,” Andrew Baker, head of the research team from the Queensland University of Technology who made the discovery, told Reuters.

The mating season lasts for several weeks and the males will typically die from their exertions.

Excessive stress hormones in the males that build up during the mating season degrade their body tissue, leading to death. Females have the ability to block the production of the hormone.

The species was found at the highest peak of the World-Heritage listed Gondwana Rainforests, in Springbrook National Park in Queensland, about 900 km (560 miles) north east of Sydney.

The findings about the new species have been published in the science journal Zootaxa. (Reporting by Thuy Ong; Editing by Robert Birsel)

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Kangaroo evolution and climate change in Australia


This video is called Mutant Planet- The Evolution of Marsupials.

Talking about Australia and climate change

From Murdoch University in Australia today:

Kangaroo evolution maps climate change

2 hours ago

The evolution of kangaroos has given a clear picture of Australia’s changing climate, according to a new study.

Murdoch University’s Dr Natalie Warburton and Dr Gavin Prideaux from Flinders University have analysed changes to the kangaroo skeleton over time which reflect Australia’s changing environment and climate.

Dr Warburton said in this way represent a sort of barometer for .

“This is important for our understanding of historical climate change in Australia,” she said.

“Our study represents the most comprehensive anatomical analysis of the evolution of modern and fossil kangaroos on the basis of the skull, teeth and skeleton – including some of the new fossil we recently identified from caves on the Nullarbor.”

The findings, published this month in the Zoological Journal of the Linnean Society, will be the most reliable and detailed kangaroo family tree to date.

They show how the abundance and diversity of macropods – which includes kangaroos, wallabies and tree-kangaroos – matches the spread of woodlands and grasslands in Australia as forests retreated to the coast over millions of years.

Macropods have been around for at least 30 million years, but difficulties in working out which species are related and when certain lineages evolved have hampered research for more than a century.

By comparing skeletons from 35 living and extinct macropod species, the researchers established that while early forms were adapted to the abundant soft-leaved forest plants, later macropods had to adapt to more arid conditions.

“The skull and teeth give us a good understanding of the sorts of food that was available in the environment,” Dr Warburton said.

“The , and in particular the feet, give us important clues about how far and fast the animals were moving, which in turn shows us whether the habitat was dense or open.”

The study also found that the small, endangered merrnine, or banded-hare wallaby, was much more distantly related to the other kangaroos and wallabies than previously thought.

“The merrnine is actually the sole survivor of an ancient group of kangaroos that separated from the rest of the family around 20 million years ago,” said Dr Warburton.

“It’s now only found on the islands of Shark Bay in Western Australia – this highlights that conservation for this species is a priority.”

Explore further: New DNA test on roo poo identifies species.

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New shrew-opossum species discovery in Ecuador


This video is called South American Marsupials.

From Wildlife Extra:

New species of shrew-opossum found in Ecuador

A few specimens already in Museum collections

October 2013. Until recently there were four known species of northern shrew-opossums, Caenolestes (Paucituberculata: Caenolestidae), which are restricted to the northern Andes of South America. However five specimens of a new species of Caenolestes have been collected in Ecuador’s Sangay National Park on the eastern slopes of the Andes.

A review of museum specimens revealed six more specimens of this species lying unrecognised in collections; the new species has been named Caenolestes sangay.

All five of the new specimens were collected in cloud forest habitats from between 2,050 to 3,500 m above sea level along a recently constructed highway. The new species appears to be uncommon.

There has been very little research into the new species, so little is known about its distribution, but it occurs in a region of high endemism. New roads and land conversion threaten mature habitats near the locality where it was found.

The discovery was published in the Journal of Mammalogy.

Good Australian tiger quoll news


This video from Australia is called Tiger Quolls at the Conservation Ecology Centre. It says about itself:

5 Sep 2012

A collection of videos of the resident Tiger Quolls (Spotted-tail Quolls) at the Conservation Ecology Centre on Cape Otway.

From Wildlife Extra:

First Tiger quoll spotted in Australian National Park for 141 years

Victoria‘s Grampians National Park spots Tiger quoll after 141 year absence

October 2013. Presumed locally extinct for 141 years, a Tiger Quoll has been caught on remote digital camera in Victoria’s Grampians National Park in Southern Australia. The animal was captured on cameras set up to monitor the Brush-tailed Rock-wallaby population. The Tiger Quoll, also known as the Spotted-tail Quoll, is a carnivorous marsupial native to Australia.

Parks Victoria‘s Manager of the Grampians Ark fox control program, Ben Holmes said: “I honestly couldn’t believe my eyes when the photos were sent through from our field crew. There is no mistaking the spotted body colour, which can only be a quoll.”

The sighting is the first confirmed live record of a Tiger Quoll in the Grampians National Park since 1872, after an animal was killed at the headwaters of the Glenelg River.

Grampians National Park Ranger in Charge Dave Roberts said this was is an exciting find for all staff who had worked on conservation programs in the Grampians over the years.

“We have been undertaking extensive fire management, fox control and other conservation works for decades and this sighting adds to our knowledge and importance of our work to conserve these species,” said Mr Roberts. “Having a native predator in the system is a great sign that the park is supporting a healthy, functioning ecosystem.”

Endangered in Victoria

Tiger Quolls are endangered in Victoria, with the south-east Australian population endangered nationally and listed as ‘near threatened’ on the International Union for Conservation of Nature red list. Tiger quolls are more common in Tasmania and New South Wales, and a few still inhabit parts of Queensland too.

Parks Victoria will now refine camera monitoring techniques to hopefully build a better picture of how widespread the population is across the Grampians National Park, following several unconfirmed sightings over the years.

Parks Victoria Chief Executive Bill Jackson said: “This is an extremely exciting rediscovery after such a long time, which highlights the critical role parks play in conserving Victoria’s unique biodiversity.”

“Victoria’s parks conserve examples of over 80% of Victoria’s plants and animals and this rediscovery confirms the Grampians National Park as stronghold for biodiversity conservation.”

A comment about this article from Britain:

Congratulations Ozz

This is incontestably superb and heartening news.

I do hope that it spurs on Australians to nurture and cherish their wonderful natural heritage, even if they see fit to elect politicians who sound like they’re living in cloud cuckoo land (no names, no pack drill – oh ok, your current prime minister – in fact thinking about it, OUR prime minister is idiotically detached environmentally too ! ).

Please be rightly delighted and hugely encouraged.

Posted by: Dominic Belfield | 18 Oct 2013 15:51:35

Australian scientists plan to relocate wildlife threatened by climate change: here.

Dingoes wrongly blamed for Australian marsupial extinctions


This video is called Bite of the Tasmanian Devil.

From the University of Adelaide in Australia:

Dingo wrongly blamed for extinctions

Dingoes have been unjustly blamed for the extinctions on the Australian mainland of the Tasmanian tiger (or thylacine) and the Tasmanian devil, a University of Adelaide study has found.

In a paper published in the journal Ecology, the researchers say that despite popular belief that the Australian dingo was to blame for the demise of thylacines and devils on the mainland about 3000 years ago, in fact Aboriginal populations and a shift in climate were more likely responsible.

“Perhaps because the public perception of dingoes as ‘sheep-killers’ is so firmly entrenched, it has been commonly assumed that dingoes killed off the thylacines and devils on mainland Australia,” says researcher Dr Thomas Prowse, Research Associate in the School of Earth and Environmental Sciences and the Environment Institute.

“There was anecdotal evidence too: both thylacines and devils lasted for over 40,000 years following the arrival of humans in Australia; their mainland extinction about 3000 years ago was just after dingoes were introduced to Australia; and the fact that thylacines and devils persisted on Tasmania, which was never colonised by dingoes.

“However, and unfortunately for the dingo, most people have overlooked that about the same time as dingoes came along, the climate changed rather abruptly and Aboriginal populations were going through a major period of intensification in terms of population growth and technological advances.”

The researchers built a complex series of mathematical models to recreate the dynamic interaction between the main potential drivers of extinction (dingoes, climate and humans), the long-term response of herbivore prey, and the viability of the thylacine and devil populations.

The models included interactions and competition between predators as well as the influence of climate on vegetation and prey populations.

The simulations showed that while dingoes had some impact, growth and development in human populations, possibly intensified by climate change, was the most likely extinction driver.

“Our multi-species models showed that dingoes could reduce thylacine and devil populations through both competition and direct predation, but there was low probability that they could have been the sole extinction driver,” Dr Prowse says.

“Our results support the notion that thylacines and devils persisted on Tasmania not because the dingo was absent, but because human density remained low there and Tasmania was less affected by abrupt climate changes.”

The study ‘An ecological regime shift resulting from disrupted predator-prey interactions in Holocene Australia‘ also involved Professors Corey Bradshaw and Barry Brook from the University of Adelaide’s Environment Institute and Professor Chris Johnson from the University of Tasmania.

Australia’s dingo is a unique species, not a kind of wild dog as previously believed, according to a new study that definitively classifies the country’s largest land predator: here.

Good koala news from Australia


This video from Australia says about itself:

A Thirsty Koala Returns and Sneezes

Feb 27, 2009

South Australia has had a three-year drought and as a result eucalypt leaves lose much of their moisture. Koalas normally get enough water from eating leaves but lately it’s been too hot so koalas have been coming to homes looking for water. This wild koala first came to our house during an extreme heat wave (see A Thirsty Koala). Three weeks later it got hot again and he came back looking much more lively.

From Queensland University of Technology in Australia:

World-first research will save koalas

The “holy grail” for understanding how and why koalas respond to infectious diseases has been uncovered in an Australian-led, world-first genome mapping project.

The joint undertaking between QUT (Queensland University of Technology in Brisbane, Australia) and The Australian Museum has unearthed a wealth of data, including the koala interferon gamma (IFN-g) gene – a chemical messenger that plays a key role in the iconic marsupial’s defence against cancer, viruses and intracellular bacteria.

Professor Peter Timms, from QUT’s Institue of Health and Biomedical Innovation (IHBI), said the IFN-g gene was the key to finding a cure for diseases such as Chlamydia and Koala Retrovirus (KoRV), currently threatening the vulnerable species.

“We know koalas are infected with various strains of Chlamydia, but we do not know why some animals go on to get severe clinical disease and some do not,” Professor Timms said.

“We also know that genes such as IFN-g are very important for controlling chlamydial infections in humans and other animals.

Identifying these in the koala will be a major step forward in understanding and controlling diseases in this species. “

The research team – made up of Professor Timms, Dr Adam Polkinghorne, Dr Ana Pavasovic and Dr Peter Prentis from QUT; The Australian Museum; veterinarians from Australia Zoo and the Port Macquarie Koala Hospital; and bioinformaticians from Ramaciotti Centre and UNSW – have sequenced the complete transcriptome from several koala tissues.

Dr Polkinghorne from QUT’s School of Biomedical Sciences said data sets from immune-related tissues of Birke, a koala who was euthanised following a dog attack, have revealed a wealth of information about the species’ immune system including the sequences of at least 390 immune-related genes.

“Virtually nothing is known about the immune system of the koala and the absence of information has been a major hinderance to our efforts to understand how Chlamydia and KoRV infections lead to such debilitating disease in this native species,” he said.

Since finding the ‘holy grail’ the QUT team has developed a molecular test to measure IFN-g expression in the blood of healthy and diseased koalas, which has already been applied to a small group of wild koalas taken to the Australia Zoo Wildlife Hospital suffering ocular and reproductive tract disease.

The results will allow researchers to pull apart the complex immune response to better understand how to successfully treat and immunise the vulnerable koala population.

The genes, which only represent about 1.8 per cent of the total set identified in the tissues, were involved in B cell and T cell activation and antigen presentation – key components of the adaptive immune response suggesting that koalas have the capability to protect themselves against microbial pathogens, such as Chlamydia.

Professor Timms’ team, who are currently trialling a Chlamydia vaccine for koalas in South East Queensland, said the koala transcriptome data also provided evidence that the KoRV virus’s genes were not just circulating in the blood, but were also fused to some of the animal’s own genes.

“By analysing this information we should be able to determine if KoRV is sitting harmlessly in these koalas or if it’s potentially triggering cancer or resulting in mild Chlamydia infections becoming a serious clinical disease,” Professor Timms said.

The finding will also help researchers understand why Queensland and New South Wales koala populations have been crippled by the spread of Chlamydia while Victorian populations are much less unaffected.

The project will also aid the conservation of other Australian wildlife, with the team of researchers revealing that the majority of koala sequences shared similarities to that of the Tasmanian Devil.

“While this finding alone is not that surprising, it does show that the immune genes of marsupials are fairly closely related,” Dr Polkinghorne said.

“This promises to benefit gene discovery and the development of immunological tools that will help us to fight diseases in our other threatened and endangered wildlife species.”

While the consortium already contains more than 12 scientists, veterinarians and bioinformaticians, Professor Timms said the team had only scratched the “tip of the iceberg”.

“The task is much larger and will require many more people to assist with analysing the data,” he said.

“Funding to date has resulted in a rich koala genetic bank, but it will fall short if we are to use this data to answer key koala survival questions.

“It is planned to expand the consortium and hold a workshop to develop the best approaches to analysing the data and hence ensure the continued survival of this iconic species.”

BirdLife Australia condemns the New South Wales (NSW) government’s decision to allow recreational hunting in the state’s national parks and reserves: here.

During the breeding season, male koalas produce ‘bellow’ vocalisations that are characterised by a continuous series of inhalation and exhalation sections, and an extremely low fundamental frequency (the main acoustic correlate of perceived pitch) [1]. Remarkably, the fundamental frequency (F0) of bellow inhalation sections averages 27.1 Hz (range: 9.8–61.5 Hz [1]), which is 20 times lower than would be expected for an animal weighing 8 kg [2] and more typical of an animal the size of an elephant (Supplemental figure S1A). Here, we demonstrate that koalas use a novel vocal organ to produce their unusually low-pitched mating calls: here.

Saving Tasmanian devils


This video from Australia is called Tasmanian Devil.

From Wildlife Extra:

Hope for threatened Tasmanian devils with scientific breakthrough

Research paves way for the development of a vaccine for the contagious cancer which is driving Tasmanian devils to the brink of extinction.

March 2013. New research paves the way for the development of a vaccine for the Tasmanian devil, currently on the brink of extinction because of a contagious cancer.

100% mortality

It has been less than two decades since scientists discovered the contagious cancer devil facial tumour disease (DFTD) which causes 100 per cent mortality in the endangered marsupials. The facial cancer, which spreads when the devils bite each other’s faces during fighting, kills its victims in a matter of months. As it has already wiped out the majority of the population with sightings of devils reduced by 85 per cent, scientists are desperate to find out more about the mysterious cancer which somehow manages to evade the devils’ immune system.

Complex problem

Until now, scientists have believed that the tumours were able to avoid detection by the immune system because the Tasmanian devils have very little genetic diversity (preventing the immune system from recognising the tumour as foreign). However, a University of Cambridge led collaboration with the Universities of Tasmania, Sydney and South Denmark has discovered that the explanation is more complex.

On the surface of nearly every mammalian cell are major histocompatibility complex (MHC) molecules. These molecules enable the immune system to determine if a cell is friend or foe, triggering an immune response if the cell is foreign and a potential threat. The new research, published in the journal PNAS, reveals that DFTD cancer cells lack these critical molecules, thereby avoiding detection by the devils’ immune system.

Professor Jim Kaufman, from the University of Cambridge’s Department of Pathology, said: “Once it was found that the cancer was escaping from the devils’ immune system, scientists needed to figure out how.”

Cure?

The researchers found that the DFTD cells have lost the expression of MHC molecules, but that the genes that code for these molecules are still intact. This means that these genes could potentially be turned back on. Indeed, the scientists showed that by introducing signalling molecules such as interferon-gamma, a protein which triggers the immune response, the DFTD cells can be forced to express MHC molecules.

Dr Hannah Siddle, lead author of the paper from the University of Cambridge, said: “Developing a vaccine based on our research could tip the balance in the favour of the devil and give them a fighting chance.”

“However, we still face some hurdles. The tumour is evolving over time and any vaccine programme would have to take this into consideration. Also, because of the difficulties of vaccinating a wild population, it may be more efficient to use a vaccine in the context of returning captive devils to the wild.”

Contagious cancer

Although the only other contagious cancer has been found in dogs (canine transmissible venereal cancer), the rapid development of DFTD highlights how quickly they can emerge.

Professor Kaufman added: “Our study has implications beyond the Tasmanian devil. Sooner or later a human strain of contagious cancer will develop, and this work gives us insight into how these diseases emerge and evolve.”

The research was funded by the Wellcome Trust.

Information courtesy of Cambridge University.