World’s oldest spider dies in Australia


This video says about itself:

27 April 2018

This female trapdoor spider, named Number 16, was the world’s oldest known spider. A lifelong resident of the Australian outback, she has just died at age 43.

Scientists have gained unprecedented insight on the lives of these eight-legged creatures, revealing unique behaviours that might help them live for so long.

While some large arachnids are known to live long lives, the latest discovery surpasses other record holders by a landslide.

From the Daily Telegraph in Britain:

Farewell, No. 16: scientists left ‘miserable’ after world’s oldest spider dies aged 43

By Henry Bodkin

27 April 2018 • 5:43pm

The world’s oldest known spider has died at the age of 43, outliving its nearest rival by 15 years, Australian scientists have reported.

Affectionately known as “Number 16”, the female Giaus Villosus [villosus; a species name should not start with a capital letter] or trapdoor spider had been under observation in the wild since its birth in 1974.

The arachnid is believed to have survived for so long by sticking to one protected burrow its entire life and expending the minimum of energy.

Previously the oldest known spider was a tarantula in Mexico, which died at the age of 28.

Published [in] the Pacific Conservation Biology Journal, the research is the life’s work of Barbara York Main, now 88, who first set eyes on Number 16 shortly after its birth.

“To our knowledge this is the oldest spider ever recorded and her significant life has allowed us to further investigate the trapdoor spider’s behaviour and popular [population] dynamics”, said Leanda Mason, a student of Professor Main’s and the study’s lead author.

“Through Barbara’s detailed research, we were able to determine that the extensive life span of the trapdoor spider is due to their life-history traits, including how they live in uncleared, native bushland, their sedentary nature and low metabolisms.”

While trapdoor spiders are poisonous, it is the males, who leave their burrows to find a mate, which are usually encountered by humans.

A typical danger in Australia is homeowners finding what they believe to be dead spiders in their swimming pools, which can then rear up and attack when removed.

The trapdoor species typically take five to seven years to mature and will then invest their energies in a single burrow, with the females rarely venturing more than a few metres away from their place of birth.

Ms Mason said of the Number 16’s death: “We’re really miserable about it.

“We were hoping she could have made it to 50 years old.”

See also here.

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Australian wombat news


This video from Australia says about itself:

George the Wombat Begins New Life in the Wild | Nat Geo Wild

11 February 2018

A famous orphaned wombat will move into new home where he’ll be closer to the wild.

Monitoring wombats for behaviors such as pacing and rump biting could help conservation efforts by increasing the success of captive breeding: here.

Australian venomous spiders, new research


This 2015 video says about itself:

Australian hospitals are in desperate need of live funnel web spiders to make anti-venom. Spider expert Stacey Denovan shows the safest way to catch them.

From San Diego State University in the USA:

World’s most venomous spiders are actually cousins

Study finds the deadly Australian funnel-web spiders and mouse spiders are more closely related than previously thought

February 15, 2018

Two groups of highly venomous spiders might be seeing more of each other at family reunions. A new study led by San Diego State University biologist Marshal Hedin has found that two lineages of dangerous arachnids found in Australia — long classified as distantly related in the official taxonomy — are, in fact, relatively close evolutionary cousins. The findings could help in the development of novel antivenoms, as well as point to new forms of insecticides.

The spiders in question are those from the families Atracinae and Actinopodidae and include Australian funnel-web spiders and eastern Australian mouse spiders, respectively. One member of Atracinae, Atrax robustus, is considered by many to be the most venomous spider in the world.

“A reasonable number of people get bitten every year, but basically nobody dies from it anymore because of the wide availability of antivenom”, Hedin said.

Historically, the spiders were thought to have diverged from a common ancestor more than 200 million years ago and therefore were only distantly related. Based on their anatomy and other traits, funnel-web spiders and mouse spiders closely resemble other species of spiders known to be distantly related. Yet based on their highly similar venom — the same antivenom can treat bites from both Atricinae and Actinopodidae — many biologists suspected these spider groups might be more closely related than previously thought.

“The funnel-webs always were an uncomfortable fit in their taxonomic place”, Hedin said. “I could see the writing on the wall.”

So he and colleagues, with help from biologists in New Zealand and Argentina, collected new spiders from both branches throughout Australia, sought out museum specimens and raided Hedin’s own collection to come up with dozens of specimens representing various branches of spiders both closely and distantly related. Then the scientists sequenced large chunks of the spiders’ genomes, looking for genetic patterns that would reveal how the species are related to one another.

After this analysis, the researchers discovered that the Australian funnel-web spiders and mouse spiders were, in fact, fairly closely related, although it’s unclear exactly when they diverged from a common ancestor. In addition to solving that mystery, Hedin and colleagues discovered the existence of three entirely new taxonomic families of spiders. The researchers published their findings last month in Nature Scientific Reports.

Online taxonomy databases have already begun updating to reflect these changes, Hedin said. “We’ve convincingly resolved this relationship.”

Knowing these spiders’ ancestry could help scientists devise a kind of general-purpose antivenom to treat bites from a wide variety of related spider species, Hedin explained. In addition, funnel-web and mouse spider venom is notable for containing many different types of peptide molecules, including some that specifically target insects. Knowing more about how their venom evolved could help bioengineers to design bio-insecticides that target insects but are harmless to vertebrate animals.

Australian fire beetles avoid heat


This 13 february 2018 video is called The impact of infrared radiation in flight control in the Australian “fire beetle” Merimna atrata.

From the University of Bonn in Germany:

Australian fire beetle avoids the heat: Its infrared organs warn the insect of hot surfaces

February 15, 2018

Summary: The Australian jewel beetle Merimna atrata has several heat sensors. Originally it was thought that it uses them to detect forest fires as the insect lays its eggs in the wood of burned eucalyptus trees. Researchers were finally able to refute this hypothesis. Instead, the beetle appears to need its heat sensors for a different purpose: to not burn its feet on landing.

The Australian fire beetle is attracted to freshly burnt wood. Experts also call this pyrophilia (“love of fire”). This behavior is not very common in insects. Merimna atrata however has a good reason for this. The dead wood provides plenty of food for the larvae of the beetle, so it uses the wood for oviposition.

But how does Merimna find a freshly burned area? For some time it has been known that the fire beetle has heat sensors with which it can detect infrared radiation. In a sense, it “sees” hot places in its environment against a cooler background. It was originally believed that the insects use this ability to detect forest fires.

“However, the IR organs in Merimna atrata are relatively insensitive,” Dr. Helmut Schmitz emphasizes. Schmitz is a lecturer at the Institute of Zoology at the University of Bonn; he has investigated thermo and infrared reception in the black insects for nearly two decades. “This actually contradicts the assumption that the IR organs enable the beetle to detect fires from a greater distance.”

Beetles on a pin

Together with his colleagues, Schmitz has now been able to demonstrate for the first time that these doubts are justified. The scientists designed an ingenious experiment for this purpose. Put simply, they stuck the beetles with their backs to the end of a pin and used this to hang them up. This left the experimental animals with the ability to fly continuously, but without moving forward. “More importantly, they were able to navigate in any direction, i.e. turning right or left,” emphasizes Schmitz.

Then the scientists stimulated the flying beetles with weak infrared radiation from the side. The beetles changed their flight direction in response, but always away from the source and never towards it.

“Merimna’s IR organs are located on both sides of its abdomen; incidentally, this is unique in the animal kingdom,” explains Schmitz. “When we occluded the IR receptors with aluminum foil, the animals no longer reacted to the radiation, but always carried on flying straight ahead. As soon as we removed the foil they displayed their original behavior again.” This observation suggests another use of the heat sensors. “Presumably they help the fire beetles avoid hot spots when approaching an oviposition site such as a freshly burnt branch; these hot spots are not visible with the naked eye to humans and animals during the day,” says Schmitz.

How the animals detect forest fires remains unclear. Even visual stimuli seem to play no role in fire detection, despite Merimna atrata having good eyesight. The researchers tested this hypothesis by showing the beetles slides of large clouds of smoke rising above a forest area. But the insects were completely unimpressed and they never changed their flight direction.

Following their nose

“We therefore assume that Merimna atrata gets its information about an ongoing fire from the smell of smoke,” concludes Helmut Schmitz. This is also important for another reason. Odors can tell you exactly what is actually burning. In contrast, this information cannot be inferred from the heat development or the appearance of a smoke plume. Merimna is very picky, it only lays its eggs in burnt eucalyptus wood and avoids other trees. If the insect was to rely on its IR sense, it would risk being lured into the wrong kind of fires.

Something quite different can be seen with a close European relative; the fire beetles of the genus Melanophila. Their larvae develop in a variety of trees. Heat perception would be quite worthwhile for them. In fact, Melanophila also has infrared sensors, but they are completely different. They can presumably detect infrared radiation even from a long distance. According to measurements and theoretical calculations, Melanophila heat sensors are at least 500 times more sensitive than those of Merimna atrata.

New mammal species discoveries


This 2016 video about mammal diversity is called Marsupials, monotremes & eutherians | Australia.

From Oxford University Press USA:

There are more mammal species than we thought

February 6, 2018

A recent study published in the Journal of Mammalogy, at Oxford University Press, highlights that over 1000 new species of mammals have been described globally during the last dozen years, a finding that contradicts the notion that our mammalian relatives are well known. This rate of species discovery parallels that seen in global amphibians, and is driven by advances in DNA analysis methods and field exploration. This new listing of all living mammal species is now publicly accessible in the Mammal Diversity Database, a website funded by the American Society of Mammalogists and National Science Foundation that seeks to continue updating mammal species data to reflect newly published research.

The number of recognized mammal species has increased over time from 4,631 species in 1993 to 5,416 in 2005, and now to 6,495 species. This total includes 96 species extinct within the last 500 years, and represents nearly a 20% increase in overall mammal diversity. The updated tabulation details 1,251 new species recognitions, at least 172 unions, and multiple major, higher-level changes, including an additional 88 genera and 14 newly recognized families. The new study documents a long-term global rate of about 25 species recognized per year, with the Neotropics (Central America, the Caribbean, and South America) as the region of greatest species density, followed closely by tropical regions of Africa, Asia, and the Indo-Pacific.

Previous sporadic releases of the Mammal Species of the World series, the latest edition of which was published in 2005, have resulted in the major time gap among estimates of mammal species number. Yet the continued steady flow of taxonomic changes proposed in peer-reviewed journals and books means that changes proposed more than a decade ago have yet to be incorporated centrally, until now. The lag between the publication and synthesis of research can hamper conservation efforts, since management decisions often depend upon the precise designation of distinctive animal populations.

“A big part of what we are aiming to do is centralize known information about mammal species diversity, and thereby democratize access to studying them”, said Nathan Upham, the study’s senior author and a postdoctoral researcher at Yale University.

To update the count of global mammal species, the researchers reviewed more than 1,200 taxonomic publications appearing after the end-2003 cutoff date for Mammal Species of the World. These changes are recorded in a variety of monographs, books, and periodicals, many of which are difficult to access.

The group of researchers included two students as co-first authors, Connor Burgin of Boise State University and Jocelyn Colella of the University of New Mexico, as well as a web programmer from Berkeley, California, Philip Kahn.

“Connor started keeping a list of known mammal species when he was 16,” said Upham, who was introduced to an 18-year-old Burgin by Don Wilson, curator at the Smithsonian Natural History Museum in Washington, DC. Comparing Burgin’s list to Upham’s tally of species described from DNA data formed the basis for this new database.

Efforts on the Mammal Diversity Database now focus on digitally linking species names to their original descriptions and to geographic populations, with the goal of establishing more accessible histories of taxonomic change. The group hopes to model the database on the real-time taxonomies already online for amphibians, birds, reptiles, and fishes.

“Mammals have lagged behind other groups in their taxonomic record-keeping,” said Upham, “which is surprising given their relevance as models for disease and human origins. It’s convenient to ignore taxonomy, so many people do — but it’s the essential language for how researchers communicate through time to study biological diversity.”

Feeding kangaroos in Australia


This 5 January 2018 video says about itself:

On this episode of Breaking Trail, Coyote joins a troop of Kangaroos for FEEDING TIME! That’s right, one of many things you can do in Australia is feed the Roos! Not only are they super friendly and adorable but they will also eat right out of the palm of your hand if you can believe it! Get ready to meet some hungry Kangaroos!

Wombat in Australia


This video says about itself:

On this episode of Breaking Trail, Coyote meets Wanda the Wombat!

Wombats are marsupials and can be found throughout a wide range of Australia. However. unlike their cousins the Koala and the Kangaroo they are primarily nocturnal…

So in this special animal encounter Coyote gets to meet one sleepy Wombat who is just about to wake up from her daytime slumber. Some might say you DON’T WAKE the WOMBAT, but Coyote feels that with a few carrots and some leafy greens as a breakfast offering, he’s got the inside track to being the Wombat’s best friend! Get ready to meet Wanda!