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.

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Australia’s climate policy is messier than a teenager’s bedroom, but is Turnbull the man to tidy it up?


Nick Rowley, University of Sydney

Much as we should remain sceptical of politicians proclaiming themselves to be decisive, no-nonsense actors on climate change, the previous prime minister, Tony Abbott, did plenty more than talk. He and his government channelled their lack of political will to address the climate problem into an enthusiastic appetite for “direct action” going well beyond the predictable abolition of the so-called “carbon tax”.

Abbott’s actions were born of an apparent ideological distaste for the whole climate agenda: he wound back the Renewable Energy Target; cut funding to the Australian Renewable Energy Agency (ARENA); and attempted to abolish and then thwart the work of the Clean Energy Finance Corporation (CEFC).

Replacing Abbott with almost anyone would be cause for celebration for anybody who believes the basic science of the global climate problem might be even half right.

But in Malcolm Turnbull we have a figure who lost the leadership of his party because of his position against Abbott on climate. He then crossed the floor of the parliament to vote for the Carbon Pollution Reduction Scheme (CPRS).

Despite having to remain wedded to the existing Abbott-Hunt policies on climate to gain the leadership, anyone who doubts Turnbull’s credentials on climate change should read his 2010 speech. His perspective on why he supported the CPRS displays a deep knowledge and conviction.

Good advice, bad outcomes

It is one of the rarely considered consequences of the sad story of Australia’s national policy response to climate change that many of our finest public servants have wasted years of effort on dutifully serving the demands of their political masters.

More than ten years ago, analysis by then Treasury Secretary Ken Henry under Peter Costello recommended a national emissions trading scheme. The advice was ignored.

In 2006 John Howard asked Peter Shergold, then head of the Department of Prime Minister and Cabinet, to examine the most effective ways to achieve the emissions reductions required. He too concluded that an emissions trading scheme was necessary. But the following year, the incoming prime minister, Kevin Rudd, ignored the advice, wanting to adopt his own approach.

Then, in 2010, Rudd’s CPRS hit the buffers of prime ministerial hubris followed by the disappointing outcome of the United Nations climate summit in Copenhagen. By then, Turnbull had already lost his job as opposition leader over his climate policy stance. With Abbott on rhetorical steroids, the debate deteriorated to resemble a talkback radio slanging match crudely dominated by toxic gesture.

Despite Julia Gillard’s noble efforts as prime minister to achieve some modicum of policy stability and continuity, her government’s initially fixed carbon pricing system was swiftly dismantled by the Abbott government, together with attempts to either abolish or thwart the efforts of new organisations such as the CEFC and ARENA, which were doing important, tangible work and investment.

Don’t look away now

It is a sad and sorry story. Much like looking into a teenager’s bedroom, the temptation is to take a quick, horrified peek and then shut the door on the whole mess.

But we can’t, largely because the issue won’t go away. The decisions taken by Australia’s major allies and trading partners will come to affect our economy whether we like it not. As Bank of England Governor Mark Carney succinctly put it in a recent speech at Lloyd’s of London, “with climate change, the more businesses invest and change with foresight, the less they will regret in hindsight”.

With his talk of “agile” government, Turnbull, the former investment banker, seems to have a similar perspective.

And what is true for businesses is also being recognised by China, India, the European Union and the United States. No longer is climate change a niche concern: it has increasingly become part of the policy and business mainstream.

Turnbull’s ascendancy to the prime ministership is potentially a vital circuit-breaker. From the moment his predecessor came to office, “climate” and “change” were two words that would rarely be heard together in the Commonwealth bureaucracy. With Abbott’s removal, those working in the central agencies, the CEFC and ARENA can breathe a collective sigh of relief and get back to the serious work of developing policy and supporting projects to reduce emissions.

Abbott’s successor has (understandably) gained power on a number of promises, including that the existing Direct Action policy will remain untouched.

But this is no great problem for Turnbull. He knows that effective climate policy must send clear, stable and continuous messages across the economy about the important and economically rational imperative of reducing emissions.

Direct action doesn’t do this. It is relevant only to the businesses that receive public money to do things that otherwise they wouldn’t. It is wasteful, and most likely so costly as to be unsustainable beyond a few years.

With the government committed to its formal UN climate pledge to cut greenhouse emissions by 26-28% below 2005 levels by 2030, Turnbull is going to need new policies to achieve this. And with countries likely to agree in Paris that their commitments should be reviewed on a five-yearly basis, it is almost unthinkable that Direct Action could be funded and sustained as Australia’s flagship climate policy over the longer term.

Assuming that the Paris summit delivers an international climate agreement in December, and that Turnbull pulls off an election victory next year, I predict that soon after we will see a renewed creativity and urgency on climate policy. Set free from the toxic pugilism of Australian climate politics, a Turnbull-led government might finally achieve the sensible national approach that has been analysed to death.

Malcolm Turnbull might just be the adult prime minister who walks into that bedroom and cleans up the climate policy mess left by his squabbling predecessors.

This is an edited and extended version of a blog post published at “Pearls and Irritations”, the blog established by John Menadue, former head of the Department of Prime Minister and Cabinet under prime ministers Whitlam and Fraser.

The Conversation

Nick Rowley, Adjunct professor, University of Sydney

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