Kate Buchanan* and Mylene Mariette* have studied incubation calling by the
iconic Australian song bird, the zebra finch.
Calls can be heard by the
embryo in the last 5 days before hatching.
Microphones placed in the
nest revealed a special call only made when the temperature was 26
degrees or higher.
Mylene Mariette devised an experiment where eggs were
placed in an artificial incubator, with parents absent.
Some eggs heard
recordings of the special call. Other eggs were deprived of the special
call.
Those chicks which heard the special calls showed clear
differences in their vocalisation when they beg. They also displayed
different growth rates. They gained less weight. This showed a clear pre
natal response to stimuli.
This is the first time incubation calling
has been shown to alter the growth and development of a bird.
In
addition, when these birds bred, they chose warmer places.
*Kate Buchanan, ARC Future Fellow, Faculty of Science, Engineering and the Built Environment, Deakin University, Geelong VIC *Mylene Mariette, Postdoctoral Research Fellow, Faculty of Science, Engineering and the Built Environment, Deakin University, Geelong VIC Links
Scientists have long worried whether animals can respond to the
planet’s changing climate.
Now, a new study reports that at least one
species of songbird—and likely many more—already knows how to prep its
chicks for a warming world.
They do so by emitting special calls to the
embryos inside their eggs, which can hear and learn external sounds.
This is the first time scientists have found animals using sound to
affect the growth, development, behavior, and reproductive success of
their offspring, and adds to a growing body of research revealing that birds can “doctor” their eggs.
“The study is novel, surprising, and fascinating, and is sure to lead
to much more work on parent-embryo communication,” says Robert Magrath,
a behavioral ecologist at the Australian National University in
Canberra who was not involved in the study.
The idea that the zebra finch (Taeniopygia guttata) parents
were “talking to their eggs” occurred to Mylene Mariette, a behavioral
ecologist at Deakin University in Waurn Ponds, Australia, while
recording the birds’ sounds at an outdoor aviary.
She noticed that
sometimes when a parent was alone, it would make a rapid, high-pitched
series of calls while sitting on the eggs.
Mariette and her co-author,
Katherine Buchanan, recorded the incubation calls of 61 female and 61
male finches inside the aviary.
They found that parents of both sexes
uttered these calls only during the end of the incubation period and
when the maximum daily temperature rose above 26°C (78.8°F).
To find out whether the calls somehow prepared the chicks for higher
temperatures, the scientists artificially incubated 166 eggs at a
standard temperature of 37.7°C (99.9°F).
During the last 5 days of
incubation, they exposed the eggs to either recorded incubation calls or
the parents’ normal contact calls.
When the chicks hatched, those that had listened to the incubation
calls were more vocal than the control nestlings.
What’s more, the
chicks that had been exposed to the incubation calls weighed less than the controls, they report online today in Science.
That could be an advantageous adaptation in a hot environment, the
scientists argue. “With a smaller body size, they’re better at losing
heat,” Mariette says.
She and Buchanan suggest that their lower body
mass might also reduce oxidative damage, the harmful buildup of unstable
molecules in proteins, fats, and DNA that can adversely affect
reproduction.
They clinched their results with data on the success of the chicks:
When kept in hot conditions, the lower weight chicks did indeed go on to
produce more fledglings in their first breeding season than did the
control birds.
But the control birds were more successful in cooler
conditions. And the incubation calls may have other lasting effects.
For
two breeding seasons, the males that heard these sounds preferred
nesting boxes that were hot, whereas the control males chose cooler
homes.
“It’s interesting and surprising that vocal communication at such an
early stage of development could have such persistent effects,” says
Renee Duckworth, an evolutionary ecologist at the University of Arizona
in Tucson.
Incubation calls were first found in superb fairy wrens (Malurus cyaneus),
another Australian songbird in a different family.
Unlike the finches,
the fairy wrens’ calls teach their embryos a special “password” to
elicit food from their parents after hatching.
Mariette and others now
suspect that the calls may be widespread and used in various ways to
program chicks for future challenges.
“This remarkable paper helps us understand how animals could adapt to
changing climate by showing that parental care alters nestling growth,”
says Sonia Kleindorfer, a behavioral ecologist at Flinders University
in Adelaide, Australia, who was not involved in the study. “It also
shows that … embryos can learn much more than we ever imagined.”
But
Kleindorfer, who studies fairy wrens, wonders whether the calls are
really sending a specific signal about the temperature, and are not just
a natural response to the heat.
She also wonders how often finches use
the incubation calls in the wild, because fairy wrens suffer increased
predation when they make these sounds.
Mariette thinks the finches’ ability to prepare their offspring for
their future environment makes sense because they live in arid habitats
and they breed whenever conditions are good—irrespective of the season.
She adds that these finches show that some animals, at least, aren’t
just sitting ducks when it comes to climate change—they may be much
better able to adapt to a warming world than we thought.
The success or failure of certain species can be used to predict the future health of an entire ecosystem, research says
The coal miner's canary provided a warning of dangerous levels of toxic gases. Photograph: Don McPhee for the Guardian
The Earth's biodiversity is under attack. We would need to travel
back over 65 million years to find rates of species loss as high as we
are witnessing today.
Conservation often focuses on the big, enigmatic animals - tigers,
polar bears, whales. There are many reasons to want to save these
species from extinction. But what about the vast majority of life that
we barely notice? The bugs and grubs that can appear or vanish from
ecosystems without any apparent impact?
Biodiversity increases resilience: more species means each individual
species is better able to withstand impacts. Think of decreasing
biodiversity as popping out rivets from an aircraft. A few missing
rivets here or there will not cause too much harm. But continuing to
remove them threatens a collapse in ecosystem functioning. Forests give
way to desert. Coral reefs bleach and then die.
New research that I have been involved in suggests that there
biodiversity has a value that has been overlooked, but could be vitally
important if we are to manage our impacts on ecosystems. Our study, published in the journal Ecology, shows
that crucial information about the overall health or resilience of an
ecosystem may be lurking in data about supposedly inconsequential
species. In fact, the presence or absence of some of the rarest species
may be giving us important clues as to how near an ecosystem is to a
potential collapse.
Such rare species we call ecosystem canaries. Like canaries that coal
miners used to check for poisonous gasses deep underground, ecosystem
canaries are often the first species to disappear from a stressed
ecosystem. Their vanishing can be linked to changes in the functioning
of ecosystems, which can serve as a warning that a collapse is
approaching.
Our study used data collected from lakes in China that showed changes
in the abundance of species from algae (diatom) and aquatic midges
(chironomid) communities as they compete for resources under
environmental pressures. From this data it was possible to identify
three types of organism: slowly-replicating but strongly competitive
'keystone' species; weakly-competitive but fast-replicating 'weedy'
species; and slowly-replicating and weakly-competitive 'canary' species.
One of the lakes mentioned in study. Photo taken in July 2015 shows Erhai Lake in Dali, in southwest
China's Yunnan Province. Yunnan plans to spend 26.4bn yuan (US$4.1bn) to
tackle pollution in the Erhai Lake, which saw blooms of blue green
algae in 1996 and 2003. Photograph: Lin Yiguang/Xinhua/Alamy
Runoff
of fertiliser from surrounding fields has a major environmental impact
on these lake ecosystems. As the situation worsens the canary species is
the first to suffer.
With
continuing degradation affecting all species, this leads to the
eventual collapse of the keystone species as they are replaced by the
weedy species. The loss of keystones tips the ecosystem into a critical
transition – the point at which a system shifts into an alternate state
which in lakes is dominated by smothering algae and absence of many
plant and animal species. Moving a lake back to a clear water, high
biodiversity state can be extremely difficult.Better to avoid the
collapse in the first place.
Waiting to observe changes in the keystone species would not allow
any intervention because the system would already be spiralling towards
collapse. By searching for changes in the structure of populations that
includes the ratio of keystone, weedy and canary species, we were able
to detect a clear signal of an impending collapse many years, sometimes
decades before the actual event. Time enough to put in place changes to
farming and other practices.
The ecological theory underpinning this approach should apply to many
other aquatic and terrestrial ecosystems. Given the extent and rapidity
of human impacts there should not be any shortage of ecosystems to
apply our findings to.
*James Dyke is a lecturer in sustainability science at the University of Southampton. Links
The new economic system should be based on localised forms of industry, finance and participatory democracy.
A revolution in consciousness is mandatory in order for a great shift to occur in the way the global economy works and the future we want, writes Polychroniou [Reuters]
In his Prison Notebooks, the Italian revolutionary Antonio Gramsci
wrote: "The crisis consists precisely in the fact that the old is dying
and the new cannot be born; in this interregnum a great variety of
morbid symptoms appear."
Today, it is the world economy, to be precise, that finds itself once
again in the midst of an interregnum. The post-war model of economic
growth that produced the golden age of capitalism is long gone, but a
new economic system has yet to be born.
The morbid symptoms around abound: Intense and growing inequality,
massive unemployment and extreme youth idleness in many parts of the
world, rapidly declining standards of living, dangerously high levels of
both public and corporate debt, a financial system that remains out of
whack, and ecological collapse.
UpFront - Is capitalism driving climate change?
Moreover, the world economy not only continues to rely on fossil
fuels to power growth, but is actually increasing the consumption of
primary energy sources - such as coal, oil and natural gas - in spite of
the phenomenon of global warming which threatens to destroy human
civilisation as we know it.
Indeed, the existing economic model is defunct: consider also the
fact that productivity growth in the advanced economies of the world
since the eruption of the financial crisis of 2008 has been extremely
slow in both absolute terms and relative to previous decades. But the
model remains deadly dangerous.
Why a new deal is not enough
In light of the aforementioned reasons, many economists around the world, including Thomas Piketty, have been proposing the implementation of a new global deal on growth in the mould of Franklin D Roosevelt's "New Deal" programmes during the 1930s.
The call for a New Deal has also been adopted by several political
movements in Europe, and the United States including Bernie Sanders and
many of his supporters.
Capitalism is a rather new, historical economic system that belongs
to a certain era of humanity, which means that there is nothing to
suggest that it will be around for ever.
The problem with this approach is that a new global deal is
inevitably structured towards the goal of saving the existing economic
system, not overcoming its ultimate contradictions and replacing it with
a new socioeconomic order, which is what today's world really needs.
Roosevelt's New Deal, probably the greatest experiment of active state intervention under capitalism, saved many people's lives, but did not even end the Great Depression.
What really ended the Great Depression in the US was the mobilisation of all economic resources to support the war effort.
Roosevelt's New Deal did not advocate or promote economic democracy,
nor did it seek to lay the basis for the emergence of a more rational
socioeconomic order.
Indeed, when concerns about inflation and the federal deficit became
widespread only a few years after the initiation of the New Deal
programmes, the Roosevelt administration decided in 1937 to cut back on
its economic stimulus, which caused the US economy to fall back into
recession.
We need a new economic system
Unless we are willing to accept social disintegration, increased
conflict and even wars as irreversible processes, and stand idly by
while global warming caused by the logic of a fossil fuel-based economy
destroys the planet, the existing system of neoliberal transnational
corporate capitalism needs to be replaced by an economic order that is
aligned with human interests and sustainable and balanced growth.
In actual practical terms, this means making a great shift away from
the processes of constant capital accumulation, possessive individualism
and economic globalisation.
It also means putting an end to the destructive practices of Western
industrial extractive technologies and be respectful of the natural
resources that sustain life.
Economic globalisation, which lies at the heart of the current
economic system, is promoting a monoculture economy, and has devastating
effects for the wellbeing of most communities in the global South and
the environment alike.
Putting a halt to the current dynamics and contradiction of economic
globalisation does not mean eliminating international trade. But what it
does require is doing away with the neoliberal trade treaties, which
have given global corporations and banks such immense wealth and power
that they can promote their own interests without concern for democracy,
workers' rights and sustainability.
As such, we need to rethink terms such as development, growth and progress.
In this case, a revolution in consciousness is mandatory in order for
a great shift to occur in the way the global economy works and the
future we want.US tribes work with scientists against climate change
Capitalism is a rather new, historical economic system that belongs
to a certain era of humanity, which means that there is nothing to
suggest that it will be around for ever.
The new economic system should be based on localised forms of
industry, finance, participatory democracy, and the use of technologies
which are congruent with community needs for the production and
distribution of food in order to eradicate poverty and hunger and
provide sustainable livelihoods.
This revolution in consciousness is already under way and it has been
embraced by millions of people throughout the developed and developing
world, particularly among urban youth, and could soon become the newest
political and social movement to emerge as the old system is dying and a
new one is struggling to be born.
*CJ Polychroniou is a political economist/political
scientist who has taught and worked for many years in universities and
research centres in Europe and the United States. Links
The COAG Energy Council was a missed opportunity to start developing a
coherent approach to the transformation to a net zero emission energy
sector.
The initiatives announced by COAG are worthy but piecemeal.
If
COAG will not take a strategic approach, it's now more important than
ever that the national government does so.
In the lead-up to the 2017
review of national climate policies the Minister urgently needs to set
in train a comprehensive investigation into how the electricity system
can deliver on security, affordability and net zero emissions before
2050.
The COAG communique notes that work on the integration of energy and
climate policy will now also include consideration of the impacts of
state and territory emission reduction policies.
This is inadequate
In considering the impact of climate and clean energy developments on
the electricity system, we need to think beyond the current 2030
emissions target to deliver a well-managed transition to zero emission
electricity.
The objectives of the Paris Agreement are to limit global temperature
rise to below 1.5-2C by reducing emissions to net zero or below.
Starting in 2018, the Agreement's framework requires countries to
progressively strengthen their targets every five years.
So the current
2030 target of 28% is the absolute least that the sector could expect.
Prudent policy-making needs to take into account the net zero objective
and the best pathway towards it.
The number of uncertainties about future energy is multiplying. But
policy uncertainty is well within governments' power to resolve.
Australia has committed internationally through the Paris Agreement to
consider a long-term emissions goal through the 2017 climate policy
review.
This is an opportunity to provide businesses who are making 30
year investment decisions with clear signals on future policy direction.
One other certainty is that Australia's highest-carbon generators, our
ageing coal burning power stations, will need to exit over the next
15-20 years if we are to deliver on our commitments.
As we saw in South
Australia, disorderly, unplanned closures can have bad consequences for
the local community, energy users, and the stability of the market as a
whole.
An orderly transition, whereby 1-2 GW of coal capacity is
withdrawn every year, with enough foresight and predictability for the
right replacement energy services to be delivered at the right time and
in the right place, is the best prospect for achieving our climate goals
and a well-managed transformation of our power supply.
We urge the national government to set up a truly comprehensive and
strategic review of the electricity system to work through these issues
and integrate this with the 2017 review.
Stephen Miles says targets harder to reach as Climate Council, WWF and Wilderness Society predict ‘panic clearing’
The Climate Council, WWF and the Wilderness Society are expecting a new
surge in clearing after the defeat of the Palaszczuk government’s bill
that attempted to restore controls on deforestation.
Photograph: Auscape/UIG via Getty Images
Australia’s prospects of meeting its climate change targets have suffered a crucial blow with the failure of land-clearing reforms in Queensland, the state’s environment minister and conservationists say.
A renewed surge in clearing is expected after Thursday’s defeat of the Palaszczuk government bill
that attempted to restore controls on deforestation. The defeat has
also dashed hopes of tackling the nation’s fastest-rising source of
carbon pollution.
However, Josh Frydenberg, the federal environment minister, insisted
Australia was “on track to meet and beat” the first hurdle of its Paris
climate pact commitments, a 5% cut in emissions by 2020.
Frydenberg’s optimism contrasts with a study released in February
showing emissions from clearing in Queensland, after the former Newman
government axed controls in 2013, had already wiped gains made under the
federal government’s emissions reductions fund.
The Climate Council, WWF and the Wilderness Society all predict
further bouts of “panic clearing” by graziers before the Palaszczuk
government’s bid to pass controls in its next term if re-elected.
And a growing rate of remnant vegetation clearing is expected to
drive a rise in carbon emissions, they say, further eroding progress
towards targets pledged by the federal government in Paris last
December.
The legislative defeat has also set the Palaszczuk government on a
renewed course of lobbying Unesco not to revisit its decision to keep
the Great Barrier Reef on its world heritage list, which was made in part because of assurances that runoff from clearing would be curtailed.
The ERF – the centrepiece of the federal government’s bid to cut
emissions by 5% by 2020 and by 26-28% by 2030 – has invested mostly in
buying back clearing permits from farmers.
Previous clearing laws in Queensland were instrumental to the former Howard government meeting carbon cut targets under the Kyoto protocol.
But
their axing has led to a doubling in clearing rates to almost 300,000
hectares a year, suggesting the creation of 108m tonnes of carbon over
the last three years, including 35.8m tonnes in 2014-15.
The ERF to date has allocated $1.7b to purchase 143m tonnes of
carbon, 98m tonnes of which relates to “vegetation projects” – mostly
buybacks of clearing permits from landholders.
Steven Miles, the Queensland environment minister, said unabated
clearing in the state made national climate change targets “that much
harder” with deeper cuts required in other sectors.
“Given it more than wipes out the ERF, it leaves the commonwealth
without a tool to achieve their targets,” he told Guardian Australia.
“If you assume that billions of dollars of ERF money just get wiped
out from land clearing, how are you achieving the cuts that they need
and they’ve committed to across the economy?
“When you’re clearing at this rate, you’re behind the eight ball when
you start doing the economic transition [to a low-carbon economy].
Drone footage shows significant land clearing in Queensland
“It’s running in the wrong direction. When your last resort for
emissions that you can’t minimise is to offset them primarily by
planting trees, they cut against each other, don’t they?”
However, Frydenberg said the ERF was “working effectively to achieve low-cost abatement”.
“Australia remains on track to meet and beat its 2020 emissions
reduction target,” he said. “The latest estimate by the Department of
Environment shows we are on track to exceed the target by 78m tonnes.”
Lyndon Schneiders, the national director of the Wilderness
Society, said emissions from clearing in Queensland would now worsen and
further eclipse ERF gains.
“I just think every bulldozer in Queensland will be out knocking down
bush at accelerated rates because that’s what happens,” he said. “The
only thing that’s keeping that 5% target [by 2020] even in the show has
been that the economy’s tanked.
“The only place where emissions have been going through the roof is around land clearing.
“I’m sure the national government does not want to just throw $2b
down the toilet in buying back emissions but they seem to be almost
powerless to do anything about what’s happening at the state level.”
Martin Taylor, a scientist for WWF, said there had already been
“massive amounts of panic clearing” in the lead up to the state
government’s ill-fated push for controls.
Tayor said WWF researchers using satellite data had identified “two
huge episodes” of 5,000 hectares and almost 7,000 hectares of remnant
forest in central Queensland cleared since the last state land and tree
cover survey.
“They’re running bulldozers through, tearing down everything except
leaving a few sticks behind and calling it ‘thinning’,” Taylor said.
“We’re discovering now that that is the main way that the Newman
government axed the ban on broadscale clearing.”
This was separate to high-value agriculture permits issued by the
former LNP government, some of which have since been frozen by the
commonwealth for assessment under the Environmental Protection and
Biodiversity Conservation Act.
Commonwealth intervention under those laws has been applauded as a
hopeful sign by conservation groups but criticised by Queensland
Coalition senators such as Ian MacDonald.
Miles
said the commonwealth intervention could help arrest the rate of some
inappropriate large-scale clearing. But their scope for cracking down
was limited to piecemeal individual cases under the EPBC laws and did
not relate to their implications for emissions.
“Short of them legislating their own tree-clearing laws, like federal
Labor said they’re going to do if elected, it really comes down to
Queensland,” Miles said.
Comment was sought from Frydenberg’s office.
The Climate Council’s chief executive, Tim Flannery, said the failure
of land-clearing legislation to pass in Queensland was “going to have a
big impact” on Australia’s efforts to meet its Paris targets.
“We may yet see a spike in land clearing following this,” Flannery
said. “Whenever farmers feel something is going to change in the future,
they clear like crazy before what they see as the axe falling.
“It’s such a pity because Queensland is just such a biodiverse place
and the sort of stuff that’s being cleared, often these bottle tree
scrubs and dry rainforest communities, are particularly significant.”
Flannery separately called for the federal government to “hammer down
on the use of fossil fuels” and stop using “biological carbon”
emissions as a “smokescreen for a lack of performance” in cutting
transport and energy sector emissions.
The tree-clearing study by environmental services company CO2
Australia also suggested the federal government’s bid to meet climate
change targets could be undermined by its under-recording of emissions
from clearing.
A federal government report last December projected that emissions
from land clearing would rise 24% from 2013 levels, from an average 37m
tonnes to an average 46m tonnes a year up to 2020 and 44m tonnes a year
between 2020 and 2030.
But Queensland government data also released last year suggested a
rate that would take national land clearings emissions to 55m tonnes a
year between 2020 and 2030.
Clearing would then emit an extra 118m tonnes of carbon next decade, a
blowout of more than 10% on reductions pledged by the commonwealth in
Paris.
Humans have changed the Earth to such an extent that some scientists say we have entered a new geological epoch?
Human activity might have pushed us into the Athropocene epoch [EPA]
There is growing evidence that human activity has changed the Earth’s
system to such an extent that we are now in a new geological age.
This is according to members of the Anthropocene Working Group who
will present their findings to the 35th International Geological
Congress, which kicks off on August 27 in Cape Town, South Africa.
If they announce that a new geological era, or epoch, has begun, this
would pave the way for a formal declaration that could happen in just
two years.
This would be a major announcement, highlighting the dramatic changes that humans have caused to the Earth.
It would confirm that the changes caused by humans are as big as
those that occurred at the end of the last Ice Age nearly 12,000 years
ago.
In fact, the rate of change of gases such as carbon dioxide and methane in the atmosphere are even greater.
Climate change: Fact or fiction?
Our new geological epoch would be called the Anthropocene, a word which comes from anthropo for 'man', and cene for 'new'.
It would bring an end to the Holocene, which began at the end of the last Ice Age.
'Welcome to the Anthropocene'
A number of recent studies argue that we are already in the Anthropocene, but the definition is fairly drastic.
Earth scientists define the Anthropocene as “the very recent rupture
in Earth’s history arising from the impact of human activity on the
Earth system as a whole”.
In order to officially mark the beginning of a new epoch, changes
must be apparent in the atmosphere, the water cycle, in plants and
animals, and in rocks.
Thanks to the dramatic increase of carbon dioxide and methane in the
atmosphere, reaching some of the aforementioned criteria will be easy.
Global temperatures have increased by an average of one Celsius in a little over a century.
Glaciers have melted, the temperature of the oceans has risen and their acidity has altered.
A number of animal and plant species have become extinct, and corals have suffered a number of devastating bleaching events.
Plastic rubbish, widely used nitrogen fertilisers and smoke from the
burning of fossil fuels will remain visible within the Earth's rock
formations for millions of years.
The idea that we are now living in the Anthropocene has been gaining
ground in recent years, and soon we will discover if geologists agree
that the new epoch has truly begun.
The start of a new geological age, however, is not a time to
celebrate. As Clive Hamilton, professor of public ethics at Charles
Sturt University in Canberra, Australia, told Nature magazine:
“Some scientists even write: 'Welcome to the Anthropocene'. At first I
thought they were being ironic, but now I see they are not. And that’s
scary. The idea of the Anthropocene is not welcoming. It should frighten
us. And scientists should present it as such.”
