How curiosity can save species from extinction


Merlin Crossley, UNSW Australia

If I had been given one wish as a child I, it would have been that the Tasmanian tiger wasn’t extinct. To me extinction was a tragedy. I expect that many people feel the same way.

But it is not easy to save dwindling populations and prevent extinctions. Sure it takes money, but it also takes knowledge. One simple story about butterflies illustrates the complexity of ecosystems and shows how important research and understanding are to preserving biodiversity.

It is the story of the European butterfly, the large blue or Phengaris arion (Maculinea arion in older literature).

In Australia we have lots of butterflies and literally countless moths; the total number is not known. In the United Kingdom, on the other hand, virtually all species have been described.

I visited England several times as a child, and at one stage I sought to see as many of the 60 different species of butterfly as possible. But I was particularly keen to see the large blue because it was rare. It was the first butterfly recorded in the British Isles in 1795 and was much prized by collectors for the very simple reason that it was so scarce.

But over the years the known populations gradually died out and it was given protected status. Britons made efforts to fence off reserves where it remained but, oddly, its numbers continued to decline. By 1979 it was declared extinct in Britain.

But why had all the steps to save this iconic species failed?

One researcher from Oxford University, Jeremy Thomas, led a team of large blue experts to investigate the ecosystem in which it existed. The first step was to try to understand the butterfly. And there was a lot to understand.

A pretty butterfly that hides a remarkable life cycle.
PJC&Co, CC BY-SA

Interdependence

It is a remarkable species. The female lays eggs on wild thyme flower buds. Each caterpillar bores into the bud and eats the growing seeds. It needs all the energy in the seeds to survive, and if more than one caterpillar is sharing the bud they will fight things out in a cannibalistic bout until only one remains. This is a taste of things to come.

After about a week eating the seeds and flower it drops to the ground and waits until it is found by a special species of ant. It excretes a substance that feeds the ant, but also influences the ant’s behaviour. The ant goes and fetches fellow ants that carry the caterpillar down into the nest.

Once inside the nest the caterpillar does a remarkable thing: it feeds on ant larvae until it finally pupates. When it is ready to emerge as a vulnerable new butterfly it begins making sounds that appear to appease the ants. It then emerges, protected by a guard of ants, and climbs up out of the nest to stretch out its wings.

The critical point is that the large blue doesn’t just depend on any old species of ant, but on very particular species. It has evolved to exude chemicals that influence red ants of the species Myrmica sabuleti or M. scabrinodis.

These ants also have very specific requirements, this time in terms of temperature and moisture. If the ground is too hot or too cold they don’t thrive and other species take over.

Ground temperature and moisture depend on the height of the grass. The grass needs to be short, so grazing is important. It turns out that fencing off reserves actually interfered with the life cycle of the butterfly because the grass grew too long, and the ground wasn’t right for the ants.

Similarly, the spread of myxomatosis and reductions in the rabbit populations also meant the grass grew too tall, again altering ground temperature and helping drive the decline in large blue populations.

Due to the careful work by Jeremy Thomas and colleagues, all this is now known. Fortunately, unlike the Tasmanian tiger, the large blue was extinct only in the British Isles, and not in mainland Europe, thus it has been possible to re-introduce it into Britain.

It has also been possible to manage the habitat to allow grazing so that the ant colonies thrive and the butterfly also seems to be doing well.

Parts of the odd life cycle of this butterfly were known as far back as 1915, but there was no understanding of the connection to the ecosystem and landscape, so the vital step of controlling the grazing was not considered.

The large blue has been successfully returned to Collard Hill in the Polden Hills in Somerset.

Curiosity

The story shows how things can be complex and inter-connected, and that only by understanding all the facets can one intercede to put things right. It also illustrates how the careful application of science can make a difference.

One can never tell when and how, or even if, new knowledge will ever be useful. Scientists collect knowledge partly because they want to improve the world, but often just out of curiosity.

Sometimes curiosity driven research is criticised as self-indulgent, and unlikely to make a real difference to our circumstances. Sometimes it is said that researchers should just go straight for the biggest problems and tackle them straight on, or that research should be aimed purely at applications. This is increasingly heard these days given the new emphasis on innovation and the commercialisation of research.

But in reality we need science most when we have tried tackling the problem and got stuck. Everything people had tried to preserve the large blue had failed. Only knowledge provided a way forward.

Curiosity driven science often provides solutions when we are stuck and without it we will sometimes remain stuck forever. In the case of the Tasmanian tiger I believe we are stuck forever, but there are many other things to preserve and careful in depth science can make a difference.

The Conversation

Merlin Crossley, Dean of Science and Professor of Molecular Biology, UNSW Australia

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

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2015, the year that was: Environment + Energy


Michael Hopkin, The Conversation

Environmental news, as a rule, doesn’t deal in triumphs. So the sight of leaders holding their arms aloft in celebration after clinching the historic Paris climate agreement will stand as a defining image of 2015 – a moment of cartharsis after more than two decades of infuriatingly sluggish climate diplomacy.

After two weeks of round-the-clock negotiations (and years of work beforehand), the Paris climate summit has delivered the first binding treaty under which all nations, rich and poor, will join the bid to limit global warming to “well under 2℃”, and possibly no more than 1.5℃.

The climate hasn’t been saved yet, despite vulnerable nations’ impressive success in lobbying for the 1.5℃ target to be included in the agreement. The emissions pledges made so far will fall well short of the goal, and will need significant strengthening under the review process enshrined in the agreement.

Nevertheless, getting all 196 parties to sign the deal was a diplomatic coup, six years after the disappointment and acrimony of the Copenhagen talks.

Midway through the conference we learned that global greenhouse emissions maybe, just maybe, have already peaked, but peaking is not enough – the agreement calls for the world to become effectively carbon-neutral by the second half of the century. The near-certainty that 2015 will be the hottest year on record is a reminder that global warming is well underway. Time and carbon budgets are tight.

Targets and auctions

The buildup to the climate summit dominated the agenda all year, in Australia and abroad. China, the world’s biggest greenhouse emitter, unveiled plans for a national emissions trading scheme, while Pope Francis made an influential call to action on the environment.

Come on world, sort it out.
Reuters/Tony Gentile

Domestically, Tony Abbott’s government pledged to cut emissions by 26-28% on 2005 levels by 2030 as its pre-Paris promise (a mediocre effort, according to some).

Earlier in the year it held its first reverse auction for the Emissions Reduction Fund, which will use public money to invest in emissions-reducing projects without a carbon tax. Doubts still remain over whether it is fit for purpose.

Energetic efforts

It was a torrid year for renewable energy, after the government succeeded in scaling back the Renewable Energy Target and told the Clean Energy Finance Corporation not to invest in wind farms (new Prime Minister Malcolm Turnbull has now reversed that move).

Coal, on the other hand, was still in favour. After hitting a legal roadblock over skinks and snakes (but not greenhouse emissions), Indian firm Adani’s controversial Carmichael coal mine in Queensland has now been re-approved. Not only that, but Attorney General George Brandis struck back at the “radical activists” who opposed the approval, announcing plans to restrict green groups from waging similar “lawfare” in the future.

One of the reasons green groups oppose the Carmichael mine is the fact that the coal will be shipped across the Great Barrier Reef. Australia faced the prospect of international embarrassment as the UN World Heritage Committee weighed up whether to add the Reef to its official list of world heritage in danger – an ignominy generally reserved for heritage sites in war-torn places like Iraq and the Congo.

Not officially in danger – but not safe yet.
Underwater Earth/Catlin Seaview Survey/Wikimedia Commons, CC BY-SA

In the event Australia was reprieved after persuading the UN that it now has policies in place to safeguard the Reef. Progress will be reviewed in 2019, and as our Reef threats series pointed out, the problems are many and complex.

Into hot water

Elsewhere in the Pacific Ocean, scientists have watched the unfolding El Niño, which officially arrived in May and has steadily gathered in force since. As drought threatens to return to the Murray-Darling Basin, meteorologists are uncomfortably aware that El Niño’s effects on Australia can be harsh, unpredictable, and hot.

Speaking of heat, you wouldn’t have wanted to be sitting in Volkswagen’s boardroom as the news broke about the company’s systematic gaming of vehicle emissions testing, bringing worldwide condemnation. It’s still not clear how widespread the issue will turn out to be, but Australian diesel drivers will face a rough road ahead regardless – 2016 is the year that Australia’s lax vehicle emissions standards will finally be brought into line with much of the rest of the developed world, potentially wiping out much of the financial advantage of driving a diesel.

You want extra emissions with that?
EPA/JULIAN STRATENSCHULTE

Of course you could always catch a tram – or at least you might in a few years, if the many light rail projects planned for Australia come to fruition. After two years of roads-only infrastructure policy under Abbott, Turnbull has changed course and will invest in public transport too. Along with the appointment of cities minister Jamie Briggs, it’s a sign that the Canberra government might finally be starting to understand cities, which after all is where most of us live.

Power plays

One car company whose star was definitely on the rise was Tesla, which branched out from electric sports cars to unveil an affordable power storage battery for use with home solar panels. It has been hailed as a game-changer in the bid to wean households off fossil-fuelled electricity, although it’s still early days in in figuring out how to smooth out the intermittency issues that still beset renewable energy.

The uncertainty over renewables and the growing urgency about getting away from fossil fuels are two reasons why nuclear is still getting attention, even in Australia where the prospect of nuclear power is politically unpalatable.

In March, South Australia launched a Royal Commission on nuclear power, uranium mining and nuclear waste, to the bafflement of those who thought we’ve had all these debates already.

True, Australia does eventually need somewhere to store its current stockpile of low-level nuclear waste from sources such as medical scans – and to that end the government shortlisted six sites ahead of a decision next year.

Australia’s only nuclear reactor. But sooner or later we’ll have to stash the waste somewhere.
AAP Image/Tracey Nearmy

But as The Conversation’s series on the future of nuclear around the world showed, other regions are grappling with bigger issues, from arms proliferation to the clean but still technically remote prospect of nuclear fusion power.

New year, new habits

While the politicians grapple with energy policy and emissions targets, what can you do to tread more lightly on the planet in 2016?

You might not be ready to live in a tiny house, go dumpster diving, or move to an ecovillage.

But every little helps, so you perhaps could colour-code your fridge to waste less food, heat your home more efficiently, eat less meat, or
become a cyclist (or maybe even just be nice to one).

You might also spare a thought for Australia’s animals – and on that front there has been some encouraging news amid the usual environmental concerns.
While things look grim for many species, like Leadbeater’s possum or orange-bellied parrots, this year conservationists
declared victory for Australia’s humpback whale population – more evidence that environmentalism can still conjure up the odd moment of triumph.

The Conversation

Michael Hopkin, Environment + Energy Editor, The Conversation

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