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Wildlife on your doorstep: share your September photos
As the seasons begin to change in most places, we would like to see and hear about the wildlife you’ve discovered in your area
Wherever you are in the world and however professional or amateur your photography set up, we would like to see your images of the wildlife living near you.
If you’re short of inspiration, have a look at some of the amazing images shared by readers around the world last month via GuardianWitness here. We regularly print readers’ best images in the Guardian newspaper and will let you know if your image should feature.
Carbon tax could wipe out polluters' profits in pursuit of Paris targets
To achieve climate agreement’s limit of 2C rise, pricing will have to increase to more than $100 a tonne, says Schroders
More than $1.5tn (£1.2tn) in company profits worldwide could be erased by taxes required to meet the Paris climate agreement, according to analysis by Schroders.
In a stark warning to investors to back more sustainable companies, the fund management group said total earnings of 12,500 global companies could fall by 20% were the world to limit itself to the 2C temperature rise target agreed in Paris through higher taxes. Schroders found prices in emissions trading would need to rise to “well over” $100 a tonne of CO2e from current levels, about $5, to encourage the move away from fossil fuels on the scale that was needed.
Continue reading...'We'd rather die than lose': villagers in Indonesia fight for a land rights revolution
A small community on the island of Sumatra is at the heart of a battle for traditional territories that could finally resolve the muddled and exploitative system of laws governing land ownership in Indonesia
It is cold and late on the Indonesian island of Sumatra. Huddled around a map, a group of elders are planning their battle strategy. In a milestone victory last year, they were promised rights to the land their village has controlled for generations, but today they have had bad news. The local inspector wants to slice off a piece of the forest where they harvest benzoin – a substance like frankincense – and give it to a large pulp company. They see this as a betrayal.
The elders debate in a mix of languages – Batak and bahasa Indonesia – while sipping tea and planning how they will resume the fight the next day. For years now, almost every day has involved this kind of planning.
Continue reading...Know your NEM: Baseload and reliability to take centre stage
Electricity bill relief package welcome news for households doing it tough
Renewable Energy Market Report: Connection worries force prices up
How Tesla’s big battery can smash Australia’s energy cartel
New “ethical” debt fund targets renewables “merchant” market
Will wind and solar be penalised by baseload hysteria?
Sparrowhawks play hard to get
Ecclesall Wood, Sheffield A close-up look at these birds – which have evolved to be invisible in domains such as this – was proving elusive
A new noise stopped me dead in my tracks; a sort of pulse-quickening, primitive shriek, more banshee wail than bird call. Through the still-bare March treetops I saw the source of the sound barrel straight overhead – my first thrilling glimpse of sparrowhawk in this neck of Ecclesall Wood, near my home.
In the long light of a clear May evening came a second sighting, not far from the first; a revelatory 10 minutes of spectacular aerobatics in the full view of Ecclesall Road South, the bird’s fluidity of movement spellbinding.
Continue reading...Powering North Queensland: renewables in coal country
Hydro Tasmania to run combined cycle gas turbine for “commercial reasons”
Energy upgrades lead to big savings for businesses in Victoria
The marbled frogmouth makes a comeback and making crunchy coconut chips
Draft ERF method: Measurement of soil carbon sequestration in agricultural systems
Draft ERF method: Measurement of soil carbon sequestration in agricultural systems
Australia-led tidal energy project sets new production records
100 years ago: woolly bear caterpillars obey the law
Originally published in the Manchester Guardian on 4 September 1917
September 3
“Woolly bears,” in a fearful hurry, race across the road; they look as if they meant business or feared the wheel of passing vehicle or heedless boot. But the caterpillar knows nothing of danger, but merely acts as heredity has taught it; it must obey laws or go under in the struggle. Most insects need a wide distribution, for too restricted a feeding area may bring famine or degeneration; in one or other of their stages insects must get to a distance from congested districts or from ravaged food-plants. Naturally this distribution or migration takes place with many insects when, in their perfect stage, they are provided with wings, but some moths are slow-flying and lethargic, too busy with nectar-sipping and egg-laying to travel far, and in these the caterpillars make the journeys, getting over as much ground as they can before they find it necessary to spin cocoons.
Related: Why gardeners should protect caterpillars
Continue reading...I have always wondered: why are some fruits poisonous?
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This is an article from I Have Always Wondered, a new series where readers send in questions they’d like an expert to answer. Send your question to alwayswondered@theconversation.edu.au
Why are some fruits poisonous when the objective of fruit is, presumably, to be eaten so that the seeds can be widely distributed with nutritive manure? – Sev Clarke, Mt Macedon
Poison fruit has captured our imaginations for centuries. Snow White’s death sleep was induced by the evil queen’s gift of a poison-laced apple. It is rumoured that deadly nightshade, a plant with naturally occurring fruit toxins, was used to kill a Roman emperor and halt an invasion of Scotland. A deadly dose of ricin from castor beans was administered to a Bulgarian dissident via the tip of an umbrella.
More recently, scientists have been trying to understand why some fruits are naturally poisonous. From the vain queen’s point of view it makes sense to poison an apple and feed it to the fairest in the land. But why do some plants offer poison fruit that has the potential to harm – or at least deter – fruit-eating animals?
Read more: Little shop of horrors: the Australian plants that can kill you
Fruiting plants and fruit-eating animals have “mutualistic relationships”, where each benefits from the other. Plants need to spread their seeds to colonise new territory, recolonise after disturbance, or avoid the dangers of staying at home (for example, if the parent plant harbours pests).
One way of doing this is to encase seeds in nutritious fruit pulp so that animals eat the fruit, digest the pulp, and later excrete the seeds with a helpful fertilising deposit of manure.
Animal-mediated (as opposed to wind- or water-mediated) seed dispersal can be particularly useful for getting seeds to specific locations. If you’ve ever wondered how parasitic mistletoe plants or strangler figs find their way onto branches high up in trees, fruit-eating birds are the answer. But why poison the pulp?
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First, how do plants poison the pulp? Plants produce a range of chemical compounds, some of which have no apparent function in primary life-maintaining processes and so are called secondary compounds.
Potentially poisonous secondary compounds are produced either in the course of development from seed to adult plant, or in direct response to attacks from plant-eaters.
Poisons in fruit pulp are typically produced during development. Unripe fruit is often toxic to protect immature seeds from attack or premature dispersal, but ripe fruit with mature seeds can also be poisonous.
So how do we explain fruit that remains poisonous even when it’s ripe and ready for dispersal? One theory is that a low level of poison in fruit encourages fruit-eating animals to move away from the parent plant (avoiding additional poison), therefore carrying seeds further away.
In some cases toxins cause constipation, ensuring that seeds stay longer in the gut and so increasing the distance they are carried. In other cases – think of prunes – they act as laxatives to ensure the quick passage of seeds with minimal time for seed damage during digestion.
There is some evidence for these hypotheses, but they’re not the full story.
There’s good fruit-eating and bad fruit-eatingNot everything that eats fruit is good for the plant. Toxins in fruit might specifically target animals, microbes and fungi that damage its seeds, while being non-toxic to species that are good seed dispersers. The fruit of deadly nightshade is lethal to many mammals but apparently harmless to some birds, and Mediterranean buckthorn fruits are toxic to some insect pests but not seed-dispersing birds.
![](https://cdn.theconversation.com/files/184295/width754/file-20170901-22435-19jow2w.jpg)
But poisons often discourage seed destroyers and dispersers alike, so plants face a trade-off between deterring assailants and attracting the animals that safely disperse their seeds. Research so far suggests that how plants balance this trade-off depends on how long they hold onto fruit.
Highly nutritious and attractive fruit is quickly found and eaten as soon as it’s ripe: think of a plum tree stripped by fruit bats in a night or two. These fruits face less risk of damage before they’re safely eaten by the right animals, so protective toxins are less important and are therefore produced in lower quantities.
On the other hand, plants with less nutritious fruit, rarer or unreliable seed-dispersers, or more predators need to protect their vulnerable seeds with toxic fruit.
Finally, fruit might be poisonous simply because the rest of the plant is toxic. This is another trade-off some plants make: toxins that protect leaves from herbivores can also end up in the fruit.
Recent research suggests that poison fruit may ultimately result from adaptation to a range of animals consuming different plant parts, so we need to consider the whole plant and its interactions with various organisms to understand the origin and function of poison fruit.
Understanding how and why plants produce poison, in their fruit or elsewhere, has led to discoveries that are valuable for reasons other than murder and mayhem. Naturally occurring plant poisons have been used for a range of medical purposes from painkillers to antimalarial and anti-cancer agents, and there are potentially many more useful plant poisons yet to be discovered in the wild.
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Julian MacPherson Brown does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond the academic appointment above.
Freedom for Miss Simpson, the penguin found 2,000km from home
A Snares penguin from islands south of New Zealand is found wounded on a Tasmanian beach. Nine months’ nursing later, she tastes the open sea again
Just before dawn on a still morning in autumn a crowd of people gathers on a beach in southern Tasmania. They watch in tense silence as a small animal shuffles across the sand. This animal, a penguin, has been the focus of nine months of care, liaison and cooperation to get to this moment – she is being released and sent back out into her world. I am privileged to be included in the farewell crew, and share the jubilation and anxiety of the people around me, all of us hoping that she will remember her path home.