Solomon Islands expedition seeks to conserve the extraordinary monkey-faced bat and giant rat


Ivy Shih, The Conversation and Tim Dean, The Conversation

The Australian Museum has announced a scientific expedition to the Solomon Islands to research a coconut cracking megabat and giant rat, with Professor Tim Flannery as one of the leaders of the program.

The expedition will be the most extensive survey of the oceanic archipelago since the 1990s and offers a rare opportunity to gain valuable insights about mammalian evolution in an isolated ecosystem.

The team will use a combination of DNA sampling, camera traps and traditional local knowledge to piece together information on the behaviour and distribution of the monkey-faced bat and giant rat. The results will influence the design of long term conservation efforts at the Solomon Islands.

The Galapagos of the Western Pacific

Map of the Solomon Islands
CIA The World Factbook/Wikimedia Commons

The Solomon Islands are a series of six major oceanic islands located in the Western Pacific Ocean. They are remarkable in that clusters of these islands have been largely isolated from major land masses throughout their geological history.

From an evolutionary biology standpoint, the Solomon Islands are invaluable as each island has developed a unique biodiversity independent of the others. Flannery has described them as “the Galapagos of the Western Pacific”.

“The islands are around 40 million years old and the fauna on each island in the chain are different,“ Professor Tim Flannery told The Conversation. “They have never been connected by a land bridge, so they have both been colonised separately either by water or flown there.

“It’s like the Galapagos Islands. Take a blank slate and let the species come in and populate it.”

There are five known species of monkey-faced bat (genus Pteralopex) and at least one species of giant rat (Solomys ponceleti) that are endemic to the Solomon Islands, and the expedition leaders hope to discover more species of both.

They are also the largest mammals on the Solomon Islands. However, sightings have been few and far in between, with current knowledge limited to museum specimens and anecdotes.

There is an urgent need to gain a greater understanding of the mega-fauna, with one species of monkey-faced bat (Pteralopex flanneryi, named after Tim Flannery) and one species of giant rat (Solomys ponceleti) classified as “critically endangered” by The World Conservation Union.

Basic questions about their biology, habitat and reproduction still remain a mystery. Flannery said that the expedition will answer those questions, which are crucial to starting conservation efforts.

“We need to start building from the ground up. To design an effective conservation method we’re in that crucial information gathering stage.”

Coconut cracking megabats

Specimens of the five currently known Monkey-faced bat species.
ivy Shih/ Australian Museum

What is known about the species of monkey-faced bats and giant rats found on the Solomons is that they have evolved characteristics unique to their species. In the absence of any other land based mammal, they have occupied an ecological niches no other bats or rats have ventured into before.

With a wing span of over a metre and a half, the monkey-faced bats are “megabats”, and are one of the biggest bats in the world. Their common name originates from their primate-like appearance.

“They dwarf the fruit bats around Sydney. The biggest ones are very striking, enormous black bats with big boxy heads,” said Flannery.

The monkey-faced bats in the remote Solomon Islands have evolved characteristic usually associated with monkeys. They have complex teeth and jaws so powerful it allows them able to crack green coconuts. The molars have a unusually large number of cusps and heavy incisors to break through the hard husks of the coconut. In addition the bats have a “double canine” with two big cusps.

Skull of a monkey-faced bat (left) showing the distinctive double canines of the species compared to the flying fox (right)
Ivy Shih/Australian Museum, Author provided

To Flannery’s knowledge, no other mammal has that kind of unique canine.

The Solmons giant rat weighs up to two kilograms and has reproductive behaviour unseen in other rat species. The last recorded sighting in 2006 of a female and young showed that they had only one young at a time.

However Flannery explained that in the absence of any mammalian carnivores, the monkey-faced bat and giant rat did not evolve any defence mechanisms. This proved especially disastrous for the species when feral cats were introduced.

“They’re a naive species. We’ve had accounts of people taking monkey-faced bats out of tree holes and they won’t even attempt to bite you. They are just so unaware of predation.”

The brink of a new era of discovery

In addition to locating the monkey-faced bat and giant rat, the team will also be canvassing the Solomon Islands for other undiscovered native mammals. Samples will also be sent to the Australian Museum Research Institute for molecular analysis to describe species scientifically. Local community involvement will also be an invaluable component.

“We are dealing with what are probably going to be fragmented specimens. There might be an old trophy skull hanging in a house for years or a jawbone. Fragmented DNA for analysis will be a big part of our work.”

Ornamental Comb worn by men from the Solomon Islands. Traditionally, the plant fibre wickerwork was woven using the wing bone of a bat.
Ivy Shih/Australian Museum Collection, Author provided

Designing a conservation program would also be crucial to ensure long term preservation of the Solomon Island biodiversity.

Despite the challenges, the research program could contribute much to the nature of mammalian conservation and research.

“The reality is that we are poised on the brink of a new era of discovery because there are so many species which have remained undetected. So there will be a new burst of activity where we will see many new species described and hopefully for the first time ever effective conservation,” said Flannery.

The Conversation

Ivy Shih, Editor, The Conversation and Tim Dean, Editor, The Conversation

This article was originally published on The Conversation. Read the original article.

Why bats don’t get get sick from the deadly diseases they carry


Michelle Baker, CSIRO

Bats are a natural host for more than 100 viruses, some of which are lethal to people. These include Middle Eastern Respiratory Syndrome (MERS), Ebola and Hendra virus. These viruses are among the most dangerous pathogens to humans and yet an infected bat does not get sick or show signs of disease from these viruses.

The recent Ebola outbreak in West Africa showed the devastating impact such diseases can have on human populations.

As treatments in the form of therapeutics or vaccines rarely exist for emerging diseases, future outbreaks of disease have the potential to result in similar outcomes.

Understanding disease emergence from wildlife and the mechanisms responsible for the control of pathogens in their natural hosts provides a chance to design new treatments for human disease.

The path to discovery

Until recently, bats were among the least studied groups of mammals, particularly in regard to their immune responses.

But even early studies of virus-infected bats provided clues that there may be differences in the immune responses of bats. It was observed that some bats were capable of clearing viral infection in the absence of an antibody response.

Antibodies are one of the hallmarks of the immune response and allow the host to respond more rapidly to subsequent infection when the same pathogen invades the body. The absence of a detectable antibody response within the bat was striking and drew our attention to the earliest stages of the immune response, called the innate immune system.

The recent sequencing of the first bat genome provided some of the first clues that the innate immune system may be key to the ability of bats to control viral infection. There is intriguing evidence for unique changes in innate immune genes associated with the evolution of flight, and bats are the only mammal capable of sustained flight.

Flight is energetically expensive and results in the production of oxygen radicals. In the research we speculated that bats have made changes to their DNA repair pathways to deal with the toxic oxygen radicals.

A number of innate immune genes intersect with the DNA repair pathways. These genes have also undergone changes, so it appears that the evolution of flight may have had inadvertent consequences for the immune system.

Bat super immunity

In humans and other vertebrates, infection with viruses triggers the induction of special proteins called interferon.

This is one of the first lines of defence following infection. It starts the induction of a variety of genes, known as interferon-stimulated genes. These genes play specific roles in restricting viral replication in infected and neighbouring cells.

Humans and other mammals have a large family of interferons, including multiple interferon-alpha genes and a single interferon-beta gene. People have 17 type I interferons, including 13 interferon-alpha genes.

Analysis published today of the interferon region of the Australian black flying fox reveals that bats have fewer interferon genes than any other mammal sequenced to date. They have only ten interferon genes, three of which are interferon-alpha genes.

This is surprising given that bats have this unique ability to control viral infections that are lethal in people and yet they can do this with a lower number of interferons.

Although interferons are essential for clearing infection, their expression is also tightly regulated. This is to avoid over-activation of the immune system, which can have negative consequences for the host.

The expression of interferon-alpha and interferon-beta proteins, which account for the majority of the antiviral response generated following viral infection, is normally undetectable in the absence of infection. It is rapidly induced following detection of a pathogen.

Yet we again see a difference in bats. The three interferon-alpha genes are continuously expressed in bat tissues and cells in the absence of any detectable pathogen. Bats appear to use fewer interferon-alpha genes to efficiently perform the functions of as many as 13 interferon-alpha genes in other species. And they have a system that is constantly ready to respond to infection.

Continual activation of the interferon response in other species can lead to over-activation of the immune response. This frequently contributes to the detrimental effects associated with viral infection, including tissue damage. In contrast, bats appear able to tolerate constant interferon activation and are continually primed for viral infection.

The bat approach in others

We are familiar with the important role bats play in the ecosystem as pollinators and insect controllers. They are now demonstrating their worth in potentially helping to protect people from infectious diseases.

The ability of bats to tolerate a constant level of interferon expression is poorly understood at the moment. But the identification of the unique expression pattern of interferons in bats is a first step in identifying new ways of controlling viruses in humans and other species.

If we can redirect other species’ immune responses to behave in a similar manner to that of bats, then the high death rate associated with diseases such as Ebola could be a thing of the past.


Peng Zhou was a co-author of this article. He’s a researcher in pathogen discovery and antiviral immunity, formerly employed at Duke–National University of Singapore Medical School and CSIRO.

The Conversation

Michelle Baker, Research scientist, CSIRO

This article was originally published on The Conversation. Read the original article.

In defence of bats: beautifully designed mammals that should be left in peace


Daniel Horton, University of Surrey

As a wildlife veterinarian, I often get asked about bats. I like bats, and I am always eager to talk about how interesting they are. Unfortunately the question is often not about biology but instead “what should I do about the ones in my roof?”.

With some unique talents and remarkable sex lives, bats are actually one of the most interesting, diverse and misunderstood groups of animals. Contrary to popular belief, they are beautiful creatures. Not necessarily in the cuddly, human-like sense – although some fruit bats with doey brown eyes and button noses could be considered so – but they are beautifully designed.

This couldn’t be illustrated better than by the discovery of the oldest known complete bat fossil, more than 53 million-years-old yet with a similar wing design to those flying around today. To put it in perspective, 50m years ago our ancestors were still swinging from the trees and would certainly not be recognised as human. But even then bats already had the combination of thin, long forearms and fingers covered by an extremely thin, strong membrane, which allowed them to master the art of powered, agile flight.

A flying fox shows off its 50 million-year-old wing design.
Duncan PJ, CC BY-SA

Soon afterwards, fossils record another game-changing adaptation in the evolution of most bats, and that is the ability to accurately locate prey using sound (what we call echolocation). These two adaptations early in their history gave bats an evolutionary edge compared to some other mammals, and allowed them to diversify into almost all habitats, on every continent except Antarctica.

Some bats are tiny.
Gillles San Martin, CC BY-SA

There are now more than 1,300 different species, divided among 26 different families (compared to fewer than 500 primate species). Indonesia alone has 219 different bat species.

It is not just a quantity though – the variety is astonishing. The thumb-sized bumblebee bat of Thailand is the smallest species, weighing just two grammes. And like other insectivorous bats, it can eat its own body weight in insects every night. At the other end of the scale, some large flying foxes have wingspans of well over a metre and, having lost the ability to echolocate, eat fruit and nectar.

The eerily pale ‘ghost bat’ roosts in the back of caves and will even eat other smaller bats.
quollism, CC BY

Everyone knows that some bats feed on blood, but despite the “vampire” myth, only three species actually feed on blood. And these haematophagous bats are only found in parts of South America. They also definitely don’t get tangled in your hair. Bats are far too good at flying.

If thus far I haven’t persuaded you to like bats, you must admit that they are useful. Bats defecate while regularly flying very long distances (up to 350km in one night), making them extremely effective at dispersing seeds. Add to that the fact that some fruit bats live in colonies up to 1m strong, and you can start to imagine their impact. So much so, they have been proven key in reforestation.

Another unappreciated and major role is as pest controllers. The sheer volume of insects that some bats species can eat makes them very effective at suppressing pest insects. Bats reduce the nuisance and disease threat of mosquitoes, and it has been estimated they save the US economy at least $3.7 billion every year through increased crop productivity and reduction of pesticide usage.

A Mauritian Tomb Bat with her pup
Frank.Vassen/flickr, CC BY

Despite their ancient design, they show some remarkable talents. One of these is shared only by several select animals. Bats are vocal learners – able to learn and then imitate sounds even in adulthood. This is likely important for the development of the complex social organisation seen in many bat species. Most surprising of all is the recent revelation that they are also members of an even more exclusive and less salubrious club: animals known to partake in fellatio during copulation.

Bats have had some bad press recently due to their association with infectious diseases, from rabies to Ebola. And they appear able to tolerate some viruses fatal to other species. If anything, that illustrates again why they should be respected, especially as various bat species are also endangered and therefore protected by law in many regions.

So my response to those interested in what to do about the bats in their roof? Leave them alone.

The Conversation

Daniel Horton, Lecturer in Veterinary Virology, University of Surrey

This article was originally published on The Conversation. Read the original article.

Papua New Guinea: New Guinea Big-Eared Bat Rediscovered


The link below is to an article that looks at the rediscovery of the New Guinea Big-Eared Bat.

For more visit:
http://theconversation.com/lost-bat-species-rediscovered-after-120-years-in-the-wilderness-26062

Australia: NSW – Eastern Horseshoe Bats in Ourimbah State Forest


The link below is to an article reporting on the largest known colony of Eastern Horseshoe Bats in Australia located in the Ourimbah State Forest in New South Wales.

For more visit:
http://www.dpi.nsw.gov.au/aboutus/news/all/2013/monitoring-eastern-horseshoe-bats

Article & Video: Tube-Lipped Nectar Bat


The link below is to an article with an embedded video showing the rare Tube-Lipped Nectar Bat, which was first discovered in Ecuador in 2005.

For more visit:
Super-tongue Bat Caught on Camera (With Video)

Article: Wildlife – The Christmas Island Pipistrelle


Tiny Native Bat Now Feared Extinct

The following link is to an article reporting on the feared extinction of the Christmas Island Pipistrelle.

For more visit:
http://news.mongabay.com/2012/0523-hance-christmas-island-pipistrelle.html

North America: Bats – White Nose Syndrome


A fungus is sweeping across North America killing millions of bats. The mortality rate for affected bat populations can be as high as 100%, meaning that bat populations in the USA and Canada are in serious trouble.

For More Visit:
http://www.huffingtonpost.com/2012/01/19/white-nose-syndrome-bat-fungus_n_1216954.html