The Queensland Dragon Heath is like a creature in the mist



File 20190110 32154 1g947f3.png?ixlib=rb 1.1

The Conversation

Fanie Venter, James Cook University

Sign up to Beating Around the Bush, a series that profiles native plants: part gardening column, part dispatches from country, entirely Australian.


The Queensland Dragon Heath, or Dracophyllum sayeri, is a small, open-branched tree that grows up to 8 metres tall. It also looks decidedly as if someone has stuck pineapple plants or bromeliads on to the tips of its branches.

It has very specific habitat requirements, and is restricted to mountaintops where it receives high rainfall and misty conditions for at least 30 days of the year. The curved and pendulous leaves move in the slightest breeze, looking like they are dancing.




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Walking towards Queensland Dragon Heath plants in the mist evokes a prehistoric feeling. I’m always subconsciously looking out and listening for approaching dinosaurs. One would think that the Dragon Heath plants, with their strap-shaped leaves, would be easy to spot in the vegetation. Not really: it is part of their camouflage on par with the stripes of tigers. When you are further than about 20 metres from a tiger in the bush, it melts into the vegetation.

For this reason, it is easier to spot the stems, with their flaky bark, than the bromelioid leaves of the Dragon Heath. It is of course another story searching for Dragon heaths in New Zealand. In the land of the long white cloud, Dragon Heath species vary from flat cushions, a mere centimetre high, to trees 18m tall, reminiscent of their Queensland counterpart.

It’s rather fun doing fieldwork there looking, at Dragon Heath in the hot sun at the foot of the mountains, then a few hours later trying to take notes with teeth chattering in blizzard conditions. Studying the New Zealand Dragon Heaths is definitely not for the faint-hearted.


Queensland Dragon Heath.
The Conversation

The dragon family

The Queensland Dragon Heath belongs to the Ericaceae, a large family of 126 genera and about 4,260 species that grow everywhere from icy tundra to steamy tropical rainforests. Ericaceae includes heathers, rhododendrons, azaleas, and blueberries.

The Dragon Heath genus was first described by French biologist Jacques-Julien Houtou de Labillardière, based on a plant he collected in New Caledonia in April 1793. The leaves and stature of the plant reminded him of the dragon trees (Dracaena draco) of the Canary Islands; hence the name Dracophyllum. He described this plant in a book about his travels, aptly named Relation du voyage a la recherche de la Perouse, published in 1800.

Canary Islands dragon tree, inspiration for the Dragon Heath’s name.
Frank Vincentz/Wikimedia Commons, CC BY-SA

Dragon Heaths grow across Australia, on the sub-Antarctic islands of New Zealand and New Caledonia. In Australia, they grow from Tasmania in the south to the tropical forests of Far North Queensland, as well as on Lord Howe Island.

Dragon Heaths vary widely, from tiny cushion plants 10mm tall (such as the cushion inka, Dracophyllum muscoides) to a much-branched tree 18m tall (the mountain neinei, D. traversii). The first DNA studies done on the genus Dracophyllum showed that they originated in Australia with two subsequent dispersals at least 16.5 million years ago, one to New Zealand and the other to New Caledonia.

The seeds of Dracophyllum are extremely light, similar to the dust-like seeds of orchids. They can travel very long distances by wind, making it easy to disperse to far-off places, especially during cyclones.

D sayeri flowers Bellenden Ker.
Photo: Fanie Venter

But the Queensland Dragon Heath is far more localised than its cousins. It is only known to grow on three mountaintops in Queensland (Mt Bellenden-Ker, Mt Bartle Frere, and the eastern slopes of Mt Spurgeon), all above 1,300m elevation. The species name D. sayeri is after the naturalist W.A. Sayer, who collected the type specimen in 1886 on Mt Bellenden-Ker, the second highest peak in Queensland.

It prefers to grow in fairly open low rainforest on mountain ridges where there is lots of air movement, and it can grow in thin layers of humus-rich granitic soils. Temperatures on the mountain peaks are normally low, with a maximum of 25℃ during the day and a minimum of 15℃ in the evenings.

A unique feature is the strap-shaped leaves that are parallel-veined, a character normally associated with monocots (lilies, grasses, sedges, and so on) rather than with dicots (plants with net-like veins).

The waxy light pink flowers are arranged in erect, loose-branching clusters. They produce ample nectar, which is popular with our feathered friends, the honeyeaters, which use their brushed-tip tongues to collect it.




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Unfortunately the Queensland Dragon Heath is difficult to grow. It is really a plant for gardens in cooler climates and the chances of growing this plant is enhanced if the soil is inoculated with micorrhiza (fungal strands that exchange nutrients between their surroundings and their host plant) and the soil is kept moist. A thick layer of leaf mulch will keep the fine roots moist and cool.

I have succeeded in growing most of the New Zealand Dracophyllum species but had limited success with the alpine species. My next challenge is to grow the Queensland Dragon Heath successfully so that we can introduce this ancient-looking gem into horticulture.The Conversation

Fanie Venter, Postdoctoral Research Fellow, James Cook University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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Murray-Darling report shows public authorities must take climate change risk seriously


Arjuna Dibley, Stanford University

The tragic recent events on the Darling River, and the political and policy furore around them, have again highlighted the severe financial and environmental consequences of mismanaging climate risks. The Murray-Darling Royal Commission demonstrates how closely boards of public sector corporate bodies can be scrutinised for their management of these risks.

Public authorities must follow private companies and factor climate risk into their board decision-making. Royal Commissioner Brett Walker has delivered a damning indictment of the Murray Darling Basin Authority’s management of climate-related risks. His report argues that the authority’s senior management and board were “negligent” and fell short of acting with “reasonable care, skill and diligence”. For its part, the authority “rejects the assertion” that it “acted improperly or unlawfully in any way”.

The Royal Commission has also drawn attention to the potentially significant legal and reputational consequences for directors and organisations whose climate risk management is deemed to have fallen short of a rising bar.




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It’s the public sector’s turn

Until recently, scrutiny of how effectively large and influential organisations are responding to climate risks has focused mostly on the private sector.

In Australia it is widely acknowledged among legal experts that private company directors’ duty of “due care and diligence” requires them to consider foreseeable climate risks that intersect with the interests of the company. Indeed, Australia’s companies regulator, ASIC, has called for directors to take a “probative and proactive” approach to these risks.

The recent focus on management of the Murray-Darling Basin again highlights the crucial role public sector corporations (or “public authorities” as we call them) also play in our overall responses to climate change – and the consequences when things go wrong.

Australia’s economy, once dominated by publicly owned enterprises, was reshaped by waves of privatisations in the late 20th century. However, hundreds of public authorities continue to play an important role in our economy. They build and maintain infrastructure, generate energy, oversee superannuation portfolios, provide insurance and manage water resources, among many other activities.

This means that, like their counterparts in the private sector, many face risks associated with climate change. Take Melbourne Water, for instance, a statutory water corporation established to manage the city’s water supply. It will have to contend with increasingly hot summers and reduced rainfall (a physical risk), and also with the risk that government policy in the future might impose stricter conditions on how water is used (a transition risk).

What duties do public authorities owe?

Our new research from the Centre for Policy Development, shows that, at the Commonwealth and Victorian level (and likely in other Australian jurisdictions), the main laws governing officials in public authorities are likely to create similar obligations to those imposed on private company directors.

For instance, a 2013 federal act requires public authority board members to carry out their duties with the degree of “due care and diligence” that a reasonable person would exercise if they were a Commonwealth official in that board position.

The concept of a “reasonable person” is crucial. There is ever-increasing certainty about the human contribution to climate change. New tools and models have been created to measure the impact of climate change on the economy. Climate risks are therefore reasonably foreseeable if you are acting carefully and diligently, and thus public authority directors should consider these risks.

The obligations of public authority directors may, in some cases, go beyond what is required of private company directors. The same act mentioned above requires Commonwealth officials to promote best practice in the way they carry out their duties. While there is still wide divergence in how private companies manage climate change, best practice in leading corporations is moving towards more systematic analysis and disclosure of these risks. Accordingly, a “best practice” obligation places an even higher onus on public sector directors to manage climate risk.

The specific legislation that governs certain public authorities may introduce different and more onerous requirements. For instance, the Murray-Darling Basin Authority’s governing legislation, the Water Act 2007, imposes a number of additional conditions on the authority. This includes the extent to which the minister can influence board decision-making.

Nonetheless, our laws set out a widely applicable standard for public authority directors.

Approaches to better manage public authority climate risks

While some public authorities are already carefully considering how physical and transition climate risks affect their work, our research suggests that standards vary widely.

As with the private sector, a combination of clear expectations for better climate risk management, greater scrutiny and more investment in climate-related capabilities and risk-management frameworks can all play a role in raising the bar. Our research highlights four steps that governments should consider:

  • creating a whole-of-government toolkit and implementation strategy for training and supporting directors to account for climate-risk in decision-making

  • using existing public authority accountability mechanisms – such as the public sector commissioner or auditor general’s office – to more closely scrutinise the management of climate-related financial risks

  • issuing formal ministerial statements of expectations to clarify how public authorities and their directors should manage climate-related risks and policy priorities

  • making legislative or regulatory changes to ensure consistent consideration, management and disclosure of climate risk by public sector decision-makers.




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Measures such as these would set clear expectations for more consistent, sophisticated responses to climate risks by public authorities. However, even without any changes, it should be clear that public authority directors have legal duties to consider climate risks – and that these duties must be taken seriously even when doing so is complicated, controversial or politically sensitive.The Conversation

Arjuna Dibley, Graduate Fellow, Steyer-Taylor Center for Energy Policy and Finance, Stanford University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Aboriginal voices are missing from the Murray-Darling Basin crisis


Bradley J. Moggridge, University of Canberra and Ross M Thompson, University of Canberra

The Murray-Darling crisis has led to drinking water shortages, drying rivers, and fish kills in the Darling, Macintyre and Murrumbidgee Rivers. This has been the catalyst for recommendations for a Royal Commission and creation of two independent scientific expert panels.

The federal Labor party has sought advice from an independent panel through the Australian Academy of Science, while the Coalition government has asked former Bureau of Meteorology chief Rob Vertessy to convene a second panel. Crucially, the first panel contains no Indigenous representatives, and there is little indication that the second panel will either.




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Indigenous meaning

Water for Aboriginal people is an important part of survival in the driest inhabited landscape on Earth. Protecting water is both a cultural obligation and a necessary practice in the sustainability of everyday life.

The Aboriginal peoples’ worldview sees water as inseparably connected to the land and sky, bound by traditional lore and customs in a system of sustainable management that ensures healthy water for future generations.

Without ongoing connection between these aspects, there is no culture or survival. For a people in a dry landscape, traditional knowledge of finding, re-finding and protecting water sites was integral to survival. Today this knowledge may well serve a broader vision of sustainability for all Australia.

While different Aboriginal Nations describe this in local ways and language, the underlying message is fundamentally the same: look after the water and the water will look after you.

Native title

In the current crisis in the Darling River and Menindee Lakes, the focus should be on the Barkandji people of western New South Wales. In 2015, the native title rights for 128,000 square kilometres of Barkandji land were recognised after an 18-year legal case. This legal recognition represented a significant outcome for the Barkandji People because water – and specifically the Darling River or Barka – is central to their existence.

Under the NSW Water Management Act, Native Title rights are defined as Basic Landholder Rights. However, the Barwon-Darling Water Sharing Plan provides a zero allocation for Native Title. The Barkandji confront ongoing struggles to have their common law rights recognised and accommodated by Australian water governance regimes.

The failure to involve them directly in talks convened by the Murray Darling Basin Authority and Basin States, and their exclusion from the independent panels, are further examples of these struggles.

Over the past two decades, Aboriginal people have been lobbying for an environmental, social, economic and cultural share in the water market, but with little success.




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The modern history of Aboriginal peoples’ water is a litany of “unfinished business”, in the words of a 2017 Productivity Commission report.

In 2010 the First Peoples Water Engagement Council was established to advise the National Water Commission, but was abolished prior to the National Water Commission’s legislative sunset in 2014.

The NSW Aboriginal Water Initiative, tasked with re-engaging NSW Aboriginal people in water management and planning, ran from 2012 until the Department of Industry water disbanded the unit in early 2017. In a 2018 progress report the Murray-Darling Basin Authority described NSW as “well behind” on water sharing plans.

Even after a damning ABC 4Corners report shed light on alleged water theft and mismanagement, the voices of the Aboriginal people of the Murray-Darling Basin were absent.

In May 2018 the federal Labor party agreed to a federal government policy package of amendments to the Basin Plan, including a cut of 70 billion litres to the water recovery target in the northern basin, and further bipartisan agreement for better water outcomes for Indigenous people of the basin.




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While the measures also included A$40 million for Aboriginal communities to invest in water entitlements, a A$20 million economic development fund to benefit Aboriginal groups most affected by the basin plan, and A$1.5 million to support Aboriginal waterway assessments, how worthwhile are they in a river with no water?

The recent crisis emphasises the perpetual sidelining of Aboriginal voices in water management in NSW and beyond. Indigenous voices need to be heard at all levels, with mechanisms that empower that involvement. Indigenous communities continue to fight for rights to water and for the protection of its spirit.The Conversation

Bradley J. Moggridge, Indigenous Water Research, University of Canberra and Ross M Thompson, Chair of Water Science and Director, University of Canberra

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Damning royal commission report leaves no doubt that we all lose if the Murray-Darling Basin Plan fails


Jamie Pittock, Australian National University

In the wake of revelations of water theft, fish kills, and towns running out of water, the South Australian Royal Commission into the Murray-Darling Basin has reported that the Basin Plan must be strengthened if there is to be any hope of saving the river system, and the communities along it, from a bleak future.

Evidence uncovered by the Royal Commission showed systemic failures in the implementation of the Murray-Darling Basin Plan. The damning report must trigger action by all governments and bodies involved in managing the basin.

The Basin Plan was adopted in 2012 to address overallocation of water to irrigated farming at the expense of the environment, river towns, Traditional Owners, and the pastoral and tourism industries.

The Commission has made 111 findings and 44 recommendations that accuse federal agencies of maladministration, and challenge key policies that were pursued in implementing the plan.




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What did the report find?

The commission found that the Basin Plan breached federal water laws by applying a “triple bottom line” trade-off of environmental and socioeconomic values, rather than prioritising environmental sustainability and then optimising socio-economic outcomes.

I and my colleagues in the Wentworth Group of Concerned Scientists provided evidence to the commission from our independent assessment of the Basin Plan in 2017, which the commission’s findings reflect.

Contrary to current government practices, the Commission recommendations include:

  • prioritising environmental sustainability
  • basing the plan on transparent science
  • acquiring more water for the environment through direct purchase from farmers
  • meeting the water needs of the Basin’s 40 Indigenous nations
  • ensuring that state governments produce competent subsidiary plans and comply with agreements to remove constraints to inundating floodplain wetlands
  • addressing the impacts of climate change
  • improving monitoring and compliance of Basin Plan implementation.

Resilience in decline

The Murray-Darling Basin is not just a food bowl. It is a living ecosystem that depends on interconnected natural resources. It also underpins the livelihoods of 2.6 million people and agricultural production worth more than A$24 billion.

The continued health of the basin and its economy depends on a healthy river – which in turns means healthy water flows. Like much of Australia, the Murray-Darling Basin is subject to periods of “droughts and flooding rains”. But over the past century the extraction of water, especially for irrigation, has reduced river flows to a point at which the natural system can no longer recover from these extremes.

That lack of resilience is evidenced by the current Darling River fish kills. More broadly, overextraction risks the health of the entire basin, and its capacity to sustain productive regional economies for future generations.

From the perspective of the Wentworth Group, we support the commission’s main recommendations, including increasing pressure on recalcitrant state governments to responsibly deliver their elements of the plan, and to refocus on the health of the river.

We particularly support recommendations related to the use of the best available science in decision-making, including for managing declining water availability under a changing climate.

We welcome the recommendation to reassess the sustainable levels of water extraction so as to comply with the Commonwealth Water Act. These must be constructed with a primary focus on the environment.

In line with this, the 70 billion litre reduction in environmental water from the northern basin adopted by parliament in 2018 should be immediately repealed. So should the ban on direct buyback of water from farmers for the environment.

We also recognise that the Basin Plan’s water recovery target is insufficient to restore health to the environment and prevent further damage, and would welcome an increase in the target above 3,200 billion litres.




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South Australian Premier Steven Marshall has taken a welcome first step in calling for a Council of Australian Governments meeting to discuss the commission’s findings. Our governments need to avoid the temptation to legislate away the politically inconvenient failings exposed by the commission, and instead act constructively and implement its recommendations.

This is not only a challenge for the current conservative federal government. The Labor side of politics needs to address its legacy in establishing the Murray-Darling Basin Authority and the Basin Plan, as well as the Victorian government’s role in frustrating the plan’s implementation by failing to remove constraints to environmental water flows.

Now, more than ever, we need strong leadership. If the Murray-Darling Basin Plan fails, we all lose.The Conversation

Jamie Pittock, Professor, Fenner School of Environment & Society, Australian National University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Death by 775 cuts: how conservation law is failing the black-throated finch


April Reside, The University of Queensland and James Watson, The University of Queensland

Nearly 20 years ago, Australia adopted national environmental legislation that was celebrated widely as a balanced response to Australia’s threatened species crisis. In the same year, Queensland introduced its Vegetation Management Act. Together, these laws were meant to help prevent further extinctions.

But have they worked?

A famous finch

We investigated whether these laws had successfully protected the habitat of the endangered southern black-throated finch.

Our study found that, despite being nominally protected under federal environmental law, habitat for the species has continued to be cleared. Just three out of 775 development applications that potentially impacted the endangered southern black-throated finch were knocked back, according to our new research.




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Defining exactly what is habitat for the black-throated finch is tricky – we don’t have oodles of data on their habitat use over time, and the extent of their sightings has declined substantially. But Queensland has excellent vegetation mapping, and we recorded all of the vegetation types in which the southern black-throated finch has been seen.

We then mapped the extent of this habitat in three different time periods: historically; at the advent of the environmental laws (2000); and current day.

Clear danger

We found that most of the black-throated finch’s habitat had been cleared before 2000, mainly for agriculture before the mid-1970s. The black-throated finch hasn’t been reliably seen in New South Wales since 1994 and is listed there as “presumed extinct”.

We looked at all the development proposals since 2000 that were referred to the federal government due to their potential impact on threatened species. 775 of these development proposals overlapped areas of potential habitat for the black-throated finch.

Only one of these projects – a housing development near Townsville – was refused approval because it was deemed to have a “clearly unacceptable” impact to the black-throated finch.

In addition to these projects, over half a million hectares of the cleared habitat were not even assessed under federal environmental laws.

We estimate that the species remains in just 12% of its original range. Yet despite this, our study shows that the habitat clearing is still being approved within the little that is left.

So in theory, Australia’s and Queensland’s laws protect endangered species habitat. But in practice, a lot has been lost.

Critical habitat

The highest-profile development proposal to impinge on black-throated finch habitat loss is Adani’s Carmichael coalmine and rail project. Adani has been given approval to clear or otherwise impact more than 16,000 hectares of black-throated finch habitat, a third of which Adani deemed “critical habitat” But there are four other mines in the Galilee Basin that have approved the clearing of more than 29,000 ha in total of black-throated finch habitat.

But it’s not just the mines. In 2018 the federal government approved clearing of black-throated finch habitat for a housing estate and a sugar cane farm, both near Townsville. Several solar farms have also been proposed that would clear black-throated finch habitat around Townsville.

To further complicate matters, the black-throated finch’s habitat is also threatened with degradation by cattle grazing. The finch needs year-round access to certain grass seeds, so where grazing has removed the seeding part of the grasses, made the ground too hard, or caused the proliferation of introduced grasses such as buffel, the habitat suitability can decrease until it is no longer able to support black-throated finches.

So while they are losing their high-quality habitat to development, a lot of their habitat is being degraded elsewhere.

Heavy cattle grazing degrades habitat for the southern black-throated finch by removing edible grass seeds.
April Reside

The federal government has placed conditions on approved clearing of black-throated finch habitat, often including “offsetting” of any habitat loss. But securing one part of the black-throated finch’s habitat in exchange for losing another still means there is less habitat. This is particularly problematic when the lost habitat is of very high quality, as is the case for Adani’s Carmichael coalmine lease.

Little by little

Our research suggests there is a real danger of the black-throated finch suffering extinction by a thousand cuts – or perhaps 775 cuts, in this case. Each new development approval may have a relatively modest impact in isolation, but the cumulative effect can be devastating. This may explain why a stronger environmental response has not occurred so far.




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So how can we prevent the black-throated finch from going extinct? The finch is endangered because its habitat continues to be lost. So its recovery relies upon halting the ongoing loss of habitat – and ultimately, increasing it. Achieving this would require a political willingness to prioritise endangered species protection.

Australia has already lost hundreds of its unique plants and animals forever. In just the last few years, we have seen more mammals and reptiles disappear to extinction. If we continue on our current path, the southern black-throated finch could be among the next to go.The Conversation

April Reside, Researcher, Centre for Biodiversity and Conservation Science, The University of Queensland and James Watson, Professor, The University of Queensland

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Geosiris is an early contender for Sexiest Plant of 2019



File 20190117 24610 1ntbifl.png?ixlib=rb 1.1

The Conversation/THawkes

Elizabeth Joyce, James Cook University

Sign up to Beating Around the Bush, a series that profiles native plants: part gardening column, part dispatches from country, entirely Australian.


It’s a pale rebel with a mysterious past, who doesn’t play by the family rules. You might not guess from looking at it, but Geosiris australiensis is my pick for the Sexiest Plant of 2019.

I might be biased though: my colleagues and I have just uncovered the amazing life, and evolutionary history of this mysterious herb. It was only found in Australia in 2017, so there’s plenty left to discover.

But here are five things we do know about this strange, alluring guy.




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You’re no sun of mine!

Geosiris (literally, “earth iris”) grow as small (5-12 cm high), pale, perennial herbs on the floor of the tropical rainforest. A single stem arises from an underground rhizome which produces a white or pale purple flower after every wet season.

Geosiris doesn’t photosynthesise. Most plants are autotrophic (auto = self, trophic = feeding) – that is, they make their own food using energy from the sun through photosynthesis. Plants photosynthesise by using green chlorophyll, stored in part of the cell known as a chloroplast.



The Conversation

However Geosiris is mycoheterotrophic (myco = fungus, hetero = other, trophic = feeding). Instead of photosynthesising, it steals the food from autotrophic plants and uses fungi as the middle man. That is why Geosiris isn’t green: it doesn’t photosynthesise so there is no green chlorophyll.

So how does Geosiris get away with this? It’s unclear, but our best guess is that Geosiris has found a way to cheat an already well-established system.

More than 90% of all plants have a cooperative relationship with fungi in the soil, in which the fungus offers up soil nutrients (such as phosphorus) to the plant in exchange for carbon. However, when plants evolve mycoheterotrophy, they work out a way of hijacking this system: mycoheterotrophs take nutrients from the fungus as well as the carbon it harvested from the photosynthesising plant.

This relationship is thought to be very specialised, with specific mycoheterotroph, autotroph and fungus species involved in each interaction. We think this is what Geosiris does, but much more research is needed into how it gets away with such a scandal, what’s in it for the fungus, and what species of fungus is involved.

The sun feeds most plants, and Geosiris steals from them using fungal associations.
Author provided

They’re the family rebel…

Mycoheterotrophy is surprisingly common in plants. Occurring in more than 500 species of flowering plants, this stealthy feeding strategy has evolved at least 47 separate times in 36 plant families, one species of liverwort, and (possibly) one conifer.

However, Geosiris earns its rebel status by being the only mycoheterotrophic genus in its family, Iridaceae, which contains many popular garden genera such as Iris, Gladiolus, Freesia and Dietes.




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Geosiris split off from its autotrophic ancestors about 53 million years ago. During this time away from the family, Geosiris did away with photosynthesis and became mycoheterotrophic.

…with a sexy, slimmed-down genome

This loss of photosynthesis was accompanied by a major change in the genes of Geosiris. Genes responsible for photosynthesis are found in the chloroplast genome. The chloroplast genome mostly contains genes responsible for photosynthesis, however also contains a few genes important for processes like energy production.

Over the past 53 million years, the number of functional genes in the Geosiris chloroplast genome has roughly halved compared with its autotrophic relative Iris missouriensis. This reduction in number of genes is not random though. The genes lost were those responsible for photosynthesis, while the genes retained have vital functions like energy production that Geosiris still needs.

Think of it like a Fitbit. You buy one with the intention of seeing your New Year fitness resolutions through, but come March your exercise regime falls by the wayside. In the meantime your Fitbit stops working but you don’t mind: you’re not using it anymore so there is no need to get it fixed. Eventually that Fitbit ends up in the bottom of your drawer, lost forever along with sundry cables, batteries and the SoFresh Greatest Hits of 2010.

In the case of Geosiris, over time photosynthetic genes become mutated but the cell doesn’t bother to fix the mutated genes because they aren’t needed. These gene mutations are passed on to offspring, and over generations the genes are eventually lost forever.

They’re rare…

For more than 100 years, there was only one species of Geosiris known to science: Geosiris aphylla from the rainforests of Madagascar. It wasn’t until 2010 that a second species was discovered in the Comoro Islands, just north of Madagascar. But then, in 2017 botanists on an expedition discovered a new species_ – Geosiris australiensis – in the Daintree Rainforest of Queensland, Australia.


Author provided

So how did such a small, mycoheterotrophic herb find its way across the vast Indian Ocean?

…and glamorous globe-trotters

The Iridaceae family originated in Australia (back when Australia was still connected to Antarctica), but around 53 million years ago the ancestor of Geosiris travelled across the Indian Ocean to Madagascar. Then, around 30 million years ago, a lineage of Geosiris managed to travel back to Australia, splitting off into the newly discovered species Geosiris australiensis.

There are a few explanations as to how the ancestors of Geosiris did so much travelling in a time before Qantas frequent flyer points. One is that they did, literally, jump across the Indian Ocean, with seeds carried by wind between Madagascar and Australia. Geosiris has minuscule “dust seeds”, only about 0.2 millimetres wide. They’re so small they can be carried by wind for long distances. Records show that similar dust seeds from orchids have been carried thousands of kilometres by wind dispersal.

A second, more likely explanation, is that Geosiris travelled overland along the perimeter of the Indian Ocean. Geosiris jumped continents during periods when the global climate was especially hot and humid. During these times tropical rain forests extended from Africa, around the coast of the Indian Ocean, all the way to Southeast Asia.




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As a result, there was a lovely tract of suitable habitat for Geosiris to inhabit and travel through. If this is the case, perhaps there are even more species of the inconspicuous and mysterious Geosiris waiting to be discovered in the rainforests of Southeast Asia.


Sign up to Beating Around the Bush, a series that profiles native plants: part gardening column, part dispatches from country, entirely Australian.The Conversation

Elizabeth Joyce, PhD candidate, James Cook University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Why we don’t know if Irukandji jellyfish are moving south


Kylie Pitt, Griffith University and Dean Jerry, James Cook University

Reports that Irukandji jellyfish might be moving south may be panicking people unnecessarily. It’s almost impossible to tell where the tiny jellyfish are along our coast, but that could change with new technology that can “sweep” the ocean for traces of DNA.




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Since the Christmas period nearly twice the usual number of people have suffered the excruciating consequences of being stung by Irukandji. The stings are rarely fatal, but can require medical evacuation and hospitalisation.

These reports of southward movement are almost a yearly tradition, often sensational, and accompanied by varying expert opinions about whether climate change is driving these dangerous tropical animals south, towards the lucrative beach tourism destinations of southeast Queensland.

But simply counting the number of Irukandji found, or the number of reported stings, tells us very little about where the species can be found.

A simple question but difficult answer

“Where are Irukandji located, and is that changing?”, might seem like a straightforward question. Unfortunately, finding the answer is not easy. The only definitive way to determine where they are is to catch them – but that poses many challenges.

Irukandji are tiny (most are about 1cm in diameter) and transparent. Along beaches they are usually sampled by a person wading through shallow water towing a fine net. This is often done by lifeguards at beaches in northern Queensland to help manage risk.

Irukandji are also attracted to light, so further offshore they can be concentrated by deploying lights over the sides of boats and then scooped up in nets. The problem is they’re are often very sparsely scattered, even in places we know they regularly occur, such as Queensland’s north. As with any rare species, catching them can confirm their presence, but failure to catch them does not guarantee their absence. Collecting Irukandji in an ocean environment is truly like searching for the proverbial needle in a haystack.

Another method is to infer their presence from hospital records and media reports of Irukandji syndrome, the suite of symptoms caused by their sting, but this method has major pitfalls. There is often a delay of around 30 minutes between the initial sting, which is usually mild, and the onset of Irukandji syndrome. Hence the animal that caused the symptoms is almost never caught and we cannot verify the species responsible.

Indeed, we do not know whether Irukandji are the only marine organisms to cause Irukandji syndrome. For example, the Moreton Bay Fire Jelly, a species of jellyfish related to Irukandji only found in southeast Queensland, and even bluebottles, which in the past couple of weeks have stung more than 10,000 people along Australia’s east coast, have also been suggested to occasionally cause Irukandji-like symptoms.

eDNA to save the day

Emerging technology may be the key to properly mapping Irukandji distribution. All animals shed DNA in large quantities into their environment (for example, skin cells and hair by humans). This DNA is called environmental DNA) (or eDNA) and genetic techniques are now so powerful that they can detect even trace amounts.

In the sea, this means we can determine whether an animal has been in an area by collecting water samples and testing them for the presence of the target species’ DNA. This technology is exciting because it provides a major upgrade in our ability to detect rare species. Moreover, it is relatively simple to train people to collect and process water samples, the results can be available within hours, and the equipment needed to analyse the samples is becoming increasingly affordable.




Read more:
The blue bottles are coming, but what exactly are these creatures?


This means an eDNA monitoring program could be easily established in Southeast Queensland to monitor the occurrence and, importantly, changes in the distribution of Irukandji jellyfish. This is because Irukandji leave traces of their genetic code in the water as they swim.

Developing the eDNA technology for use with Irukandji would cost a few hundred thousand dollars – a relatively small price to pay to improve public safety, to provide stakeholders with some control over their ability to detect Irukandji, and to create some certainty around the long-term distribution of these animals.


The authors would like to acknowledge the significant contribution to this article by Professor Mike Kingsford (James Cook University).The Conversation

Kylie Pitt, Professor, Griffith University and Dean Jerry, Associate Professor of Marine Biology and Aquaculture, James Cook University

This article is republished from The Conversation under a Creative Commons license. Read the original article.