Venezuelan opossums and the origin of species


This video, in Spanish, from Venezuela about a mouse opossum is called Marmosa robinsoni.

From Wildlife Extra:

New study could change the traditional view of how species come about

A team of researchers from the City University of New York working on the Península de Paraguaná in Venezuela have made a discovery that could revolutionise our understanding of how the origin of a new species takes place.

Up to now it has been accepted that the primary drivers in a species becoming isolated, and consequently developing sufficiently separate characteristics to become genetically distinct, are physical in nature – the uplift of mountains, the formation of islands, the change in the course of a river, creating barriers.

The findings of the study of two species of mouse opossums, Marmosa xerophila and Marmosa robinsoni, have now added interactions among species as another way that populations can become geographically isolated, which could promote the formation of new species.

In their paper the authors, Eliécer E Gutiérrez, Robert A Boria and Robert P Anderson, say that these interactions might include, ‘the presence of particularly effective predators or strong competitors, or the absence of important prey or essential mutualistic species.’

This new theory has come about as a result of observations on the Paraguaná peninsula, which is separated from the mainland only by a spit of sand, in which the researchers found that M. robinsoni has become separated from populations of the same species found on the mainland, not because the habitat in between is unsuitable, but because it is mostly occupied by M. xerophila.

The inability of individuals of that population of M. robinsoni to mate with individuals of mainland populations could, in time, lead to their genetic differentiation and the origin of a new species.

To read more about the study go to www.ecography.org/content/august-2014.

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.