If you were a honeybee, how would you choose where to find flowers? Imagine your first flight out of the hive searching for food. What would you do if you saw flower patches with one flower, or three, or twelve, or twenty?
Our new study, published in the Journal of Experimental Biology, tested honeybees on exactly this question. We wanted to understand how honeybees choose where to forage in environments like greenhouses where our food is pollinated, in local parks, or in our own backyards.
Specifically, our research looked at whether honeybees with no specific numerical training could choose a flower patch based on the quantity of flowers it had.
We found the bees could tell the difference between groups of 1 vs 4 flowers – but not between, say, 4 vs 5. Basically, they couldn’t differentiate between groups of 2 or more flowers.
A honeybee pollinating a strawberry plant flower in a greenhouse. Adrian Dyer/RMIT University
A mathematical matter of life and death
The ability to tell the difference between two quantities can mean life or death for an animal. “Quantity discrimination” can be vital for survival in tasks including:
resource comparison: choosing a larger quantity of food
aggressive interactions: choosing to avoid conflicts with larger groups of individuals, and
avoiding predators: choosing to stay with a larger group of animals of the same species to reduce your chance of being eaten.
We are gaining a better understanding of quantity discrimination across the animal kingdom. Primates and other mammals, amphibians, reptiles, birds and fish all display some form of quantity discrimination in day-to-day tasks. For example, fish use quantity discrimination to stay in larger groups to reduce the chance of being eaten by a predator.
However, little is known about spontaneous number choices by insects.
Honeybees assess the available flowers based on several factors, including scent, colour, shape and size.
Backyard flowers; which patch to choose if you were a bee? Adrian Dyer/RMIT University
Honeybees typically visit around 150 individual flowers per flight from the hive to collect resources such as nectar or pollen. For a honeybee, a high quantity of flowers in a single area would mean less energy exertion than having to fly to many flower patches with less flowers.
Using different numbers of artificial flowers, we wanted to test whether individual honeybees could discriminate between a range of quantities, and how they might determine the quality of a flower patch.
Our honeybees were shown pairs of flower quantities ranging from easier number comparisons (such as 1 flower vs 12 flowers) to more challenging scenarios (such as 4 flowers vs 5 flowers).
The experimental set-up (left) and the quantity comparisons (right). Honeybees succeeded at spontaneously discriminating between 1 vs 12, 1 vs 4, and 1 vs 3 flowers, but no other comparisons. The honeybees were trained to associate single yellow dots with sugar water before being shown quantity comparisons. Scarlett Howard
Interestingly, despite previous findings that trained honeybees can discriminate between challenging quantities and can also learn to add and subtract, the bees performed poorly in our spontaneous number task.
We found they were only able to discriminate between 1 vs 3, 1 vs 4, and 1 vs 12 flowers – wherein they preferred the larger quantity. When 1 flower was an option they succeeded, but confused any comparisons between groups of 2 flowers or more.
This result suggests flower patch choice based on numerical-type cues is difficult for honeybees. And this has implications for how flower displays are interpreted.
A honeybee flies towards three flowers. Scarlett Howard
With today being World Bee Day, why not take the opportunity to discover what bees are doing in gardens near you. Chances are they’re going to any flower patch with more than one flower, rather than paying much attention to absolute numbers.
The numbers of people cycling and walking in public spaces during COVID-19 has skyrocketed. Cities from Bogota to Berlin and Vancouver have expanded bike lanes and public paths to accommodate the extra cycling traffic. In Australia, the New South Wales government is encouraging councils to follow suit.
Mandatory social distancing under COVID-19 is disrupting the way we live and work, creating new lifestyle patterns. But once the crisis is over, will – and should – the picture return to normal?
That’s one of many key questions emerging as the precise effect of the pandemic on carbon emissions becomes clear.
Our research published today in Nature Climate Change shows how COVID-19 has affected global emissions in six economic sectors. We discovered a significant decline in daily global emissions – most markedly, on April 7.
The analysis is useful as we consider the deep structural change needed to shift the global economy to zero emissions.
Take, for example, our quieter streets. The fall in road traffic was a main driver of the global emissions decline. So, if we encourage cycling and working from home to continue beyond the current pandemic, our climate goals will become far more achievable.
Global daily fossil emissions of carbon dioxide in million tonnes. Dash lines represent different future scenarios in the evolution of the pandemic and confinement levels.
Crunching the numbers
At the end of each year we publish the Global Carbon Budget – a report card on global and regional carbon trends. But the unusual circumstances this year prompted us to run a preliminary analysis.
We calculated how the pandemic influenced daily carbon dioxide emissions in 69 countries covering 97% of global emissions and six economic sectors.
It required collecting new, highly detailed data in different ways, and from diverse sources.
For example, we examined surface and air transport activity using data from TomTom and Apple iPhone direction requests, highway traffic records and airport departures. We used daily data to estimate changes in electricity usage.
And we built an index showing the level and size of the population under confinement in each country, to extrapolate the available data worldwide.
The pandemic’s peak
In early April, the reduction in global activity peaked. On April 7, global emissions were 17% lower than an equivalent day in 2019.
Total daily emissions in early April were similar to those observed in 2006. The fact that the world now emits as much under “lockdown” conditions as it did under normal conditions just 14 years ago underscores the rapid emissions growth in that time.
Road traffic contributed the most to the emissions decline (43%). The next biggest contributors were the power sector (electricity and heat) and industry (manufacturing and material production such as cement and steel). These three sectors combined were responsible for 86% of the fall in daily emissions.
The peak daily fall in global aviation activity (60%) was the largest of any sector we analysed. But aviation’s contribution to the overall fall in emissions was relatively small (10%) because it makes up just 3% of global emissions.
As people stayed at home, we found a small increase in global emissions from the residential sector.
In Australia, our widespread, high-level confinement triggered an estimated fall in peak daily emissions of 28% – two-thirds larger than the global estimate of 17%.
The 2020 outlook
We assessed how the pandemic will affect carbon dioxide emissions over the rest of 2020. Obviously, this will depend on how strong the restrictions are in coming months, and how long they last.
If widespread global confinement ends in mid June, we estimate overall carbon emissions in 2020 will fall about 4% compared to 2019. If less severe restrictions remain in place for the rest of the year, the reduction would be about 7%.
If we consider the various pandemic scenarios and uncertainties in the data, the full range of emissions decline is 2% to 13%.
Now for the important context. Under the Paris climate agreement and according to the United Nations Gap report, global emissions must fall by between 3% and 7% each year between now and 2030 to limit climate change well below 2℃ and 1.5℃, respectively.
Under our projected emissions drop, the world could meet this target in 2020 – albeit for the wrong reasons.
Stabilising the global climate system will require extraordinary changes to our energy and economic systems, comparable to the disruption brought by COVID-19.
Victoria’s Yallourn coal station. COVID-19 offers a chance to restructure energy systems. Wikimedia
A fork in the road
So how could we make this byproduct of the crisis – the emissions decline in 2020 – a turning point?
A slow economic recovery might lower emissions for a few years. But if previous global economic crises are any indication, emissions will bounce back from previous lows.
But it need not be this way. The recent forced disruption offers an opportunity to change the structures underpinning our energy and economic systems. This could set us on the path to decarbonising the global economy.
Let’s consider again the extra people now walking and riding bikes. What if governments took the chance now to support such active, low-emissions travel, and make it permanent? What if we accelerate the rollout of electric cars, bikes and scooters, to both broaden transport options and save lives through cleaner city air?
Encouragingly, the NSW government recently announced a A$15 million fund to help councils create bigger public thoroughfares and extra road crossings during the crisis. If the community embraces the changes, they may become permanent.
And Paris will invest €300 million (A$500 million) into a 650km bicycle network post-lockdown, including new “pop up” cycleways established during the pandemic.
The crisis has opened the way for other structural change. People and businesses have been able to test what travel is essential, and when alternative remote communication might be equally or more efficient.
Finally, energy and material consumption dropped during COVID-19. While such forced reductions are not a long-term answer to reducing greenhouse gas emissions, lower consumption can be achieved in other ways, such as new types of energy efficiency, that allow both environmentally sustainable development and rising well-being, incomes and activity.
We can rapidly return to the old “normal”, and the emissions pathway will follow suit. But if we choose otherwise, 2020 could be the unsolicited jolt that turns the global emissions trend around.
The intricacies of climate change policy have not been front of mind for the Australian government this last half year, but the issue is now back on the agenda. Yesterday a review chaired by energy industry executive Grant King into new low-cost sources of emissions reduction was released. The government has accepted many of its recommendations.
Federal energy minister Angus Taylor says the changes create new ways to reduce emissions across the industrial, manufacturing, transport and agriculture sectors.
The package spells a broadening of existing mechanisms and may open the door to some better outcomes. But the existing climate policy patchwork remains deeply inadequate, and in practice the changes may do little more than channel government funding to industry.
Climate policy changes will funnel public money to private industry. Mick Tsikas/AAP
The role of carbon capture and storage and storage
In line with the review’s recommendation, the government’s emissions reduction fund will be extended to projects using carbon capture and storage (CCS) technology.
CCS involves capturing carbon dioxide from sources such as power stations, gas plants or cement plants and pumping it underground. It tends to be technically difficult and costly per unit of tonne of emissions saved, and usually does not capture all of the emissions.
The Emissions Reduction Fund (ERF) has been the government’s primary climate policy mechanism. It gives subsidies to projects that are deemed to reduce carbon emissions – to date, mainly in agriculture and forestry. The policy is vastly less effective and efficient than the carbon pricing mechanism it replaced in 2014.
The obvious criticism is that extending government support to CCS locks in some fossil fuel use, when Australia has great opportunities to put our energy system on a zero-emissions footing using cheap renewable energy.
However, in the path to decarbonising Australia’s economy, the technology may well have a role in some industrial applications such as cement production and natural gas processing. In principle it makes sense to include any technology in a policy mechanism, as long as it is cost-competitive.
In practice, carbon capture and storage projects in Australia would require far more to be economically feasible. This is because the additional cost per tonne of carbon dioxide removed is usually far higher than in typical agriculture and forestry projects. Replacing fossil fuels with renewable energy, or saving energy through better efficiency, is typically also far cheaper than cutting emissions through CCS.
So on present settings, where all project types receive the same rate of subsidy, including CCS might be mostly just a nod to the relevant interest groups. Methodologies for establishing and monitoring projects would be established by the bureaucracy but it seems unlikely that many projects would happen.
CCS traps carbon from sources such as coal stations. Wikimedia
Energy technology support
The King review also calls for expanding the remit of the Australian Renewable Energy Agency (ARENA) and the Clean Energy Finance Corporation (CEFC) to make them “technology neutral”, so the agencies could support technologies across all sectors of the economy.
This implies expanding ARENA’s research and development activities, and the CEFC’s project finance, to the transport and industry sectors. These are the next big areas for decarbonisation after electricity, and it makes sense to channel resources into them.
A “technology neutral” approach could include carbon capture and storage. ARENA and CEFC make their own decisions about their investments within a broad mandate by government. It is important this remains so, allowing the most promising technologies to be supported, irrespective of the apparent preferences by government for fossil fuel-based technologies.
Broadening the ERF
The review recommends other changes to broaden the ERF, including to make it easier for smaller projects in agriculture and forestry to participate. This may have been prompted by the fact that the last two ERF auctions resulted in only a small number of projects and small volume of contracted emissions reductions.
This change may get extra projects over the line. But it does not fix the fundamental problem with the ERF, or its successor the Climate Solutions Fund.
The scheme pays businesses, in the form of credits, when they take steps to reduce emissions relative to a hypothetical baseline. Since it is generally impossible to know whether a company’s action to reduce emissions would have happened anyway, we can’t know to what extent claimed reductions are real. Despite elaborate estimation methodologies, the fundamental problem remains.
Under an effective and efficient climate policy framework, the ERF would either not exist or have a relatively minor role. But Australia is a long way from effective and efficient climate policy.
Australia is a long way from an effective climate policy. Sergio Perez/Reuters
Softly, softly towards carbon trading?
Under the government’s Safeguard Mechanism, a company emitting carbon emissions beyond its baseline is required to buy emissions reductions credits to cover the excess.
But in practice, the baselines are set so high that projects rarely reach them, and those that do receive exemptions.
The new recommendation, accepted by the government, is to give emissions credits to companies that stay below their baselines, if it was the result of investment in “transformative” emissions-saving measures. This would create an incentive to do better, rather than just the existing, muted incentive not to do worse than a very unambitious standard.
The question is, who would buy these credits? The review suggests the government, or companies that exceed their baselines, might buy them. The former would expand the subsidy approach to emissions cuts even further. This is quite unnecessary: private money in industry is available for relevant investments if the right incentives or regulations are in place.
But what holds promise is if companies emitting over their baselines have to buy credits from companies that operate below the baseline.
That would create a form of carbon trading. There would be a market price for emissions in industry, and companies would move towards establishing cost-effective measures to curb emissions. There would be no money flowing to or from government, as trades would be only between companies.
The safeguard mechanism was originally designed with this possibility in mind, and perhaps now the door is opening a fraction.
But to create real demand for emissions credits, and a meaningful price on emissions in industry, emissions baselines would have to be drastically lowered and no more exemptions granted. Companies running old, inefficient equipment, of which there are many in Australia, would be put on the spot.
Given the government’s deep aversion to carbon pricing, and the likely opposition by some industry players, this is perhaps more pious hope than imminent prospect.
Some industry players oppose carbon pricing. Dave Hunt/AAP
Spend, spend?
At least for now, we will probably only see a government-funded carrot given to some, and no stick. Government handouts to individual companies will continue to be the measure of Australia’s climate policy.
In these times of dramatic fiscal spending, sending a few more billion dollars of public money to businesses to subsidise new equipment may not seem a big deal. But one day, all that money needs to be recouped through taxation. It will then be obvious that industry should have been required to spend its own funds to cut emissions, and that a comprehensive market mechanism would have led to more efficient and productive investment choices.
Abolishing Australia’s carbon pricing mechanism in 2014 was a consequential failure of politics. The fine-tuning of the patchwork of policies that followed does not make up for it.
Kevin's Walk on the Wild Side 