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A Big Country
Anti-fracking activist spared jail after refusing to pay court £55,000
Tina Louise Rothery – part of a protest group known as the Nanas – staged a three-week occupation of a field near Blackpool
An anti-fracking campaigner has been spared jail after she refused to pay more than £55,000 of legal fees to the oil and gas firm Cuadrilla.
Tina Louise Rothery, 54, had been ordered to pay £55,342 of fees to the British company and a group of landowners, or face a 14-day prison sentence, after she sought to stop an injunction that would prevent protesters gathering on a stretch of land being considered for shale gas exploration.
Continue reading...National Geographic nature photographer of the year 2016 – in pictures
The annual National Geographic nature photographer of the year attracts thousands of entries from across the globe. Here’s a selection of the winning images
Continue reading...Nature laws victory, giraffes and Google – green news roundup
The week’s top environment news stories and green events. If you are not already receiving this roundup, sign up here to get the briefing delivered to your inbox
Continue reading...Japan tests innovative magnetic tether for slowing space junk
Indigenous land rights key to stopping deforestation in Central America
Without their traditional land managers, conservation reserves in Central America are left vulnerable to corporate interests, report finds. Climate Home reports
Conservation reserves in Central America have shut indigenous peoples off from their traditional lands and driven deforestation, community leaders have told Climate Home.
Since revolution in the region started to wind down in the 1980s, there has been an internationally celebrated trend to create large conservation areas. Hundreds of thousands of square kilometres of forest have been placed within borders designed to protect them.
Continue reading...Is Planet Earth II nature's answer to Strictly?
The week in wildlife – in pictures
A grey crane, bright red autumnal leaves and Tibetan gazelles are among this week’s pick of images from the natural world
Continue reading...ECB's quantitative easing programme investing billions in fossil fuels
EU emissions pledge could be undermined by bank’s investments in oil, gas and auto industries, new analysis shows
The European Central Bank’s (ECB) quantitative easing programme is systematically investing billions of euros in the oil, gas and auto industries, according to a new analysis
The ECB has already purchased €46bn (£39bn) of corporate bonds since last June in a bid to boost flagging eurozone growth rates, a figure that some analysts expect to rise to €125bn by next September. On Thursday the bank said it would extend the scheme until 2018.
Continue reading...100 million year old dinosaur tail is discovered
Rare tiny creatures found in loch near Kinross
Alan Finkel warns investment has stalled over climate policy uncertainty
Australia’s chief scientist vows to ‘thoroughly analyse all options’ for energy market despite row over emissions trading
Australia’s chief scientist, Alan Finkel, has tried to stay out of the fresh political row over emissions trading but says his review of the energy market will continue to analyse all the options to ensure future security of power supply and compliance with climate obligations.
Finkel’s comments follow a briefing he gave on Friday to the prime minister and state and territory leaders about his preliminary report about the state of Australia’s energy market. He warned that investment had stalled because of national policy uncertainty, and concluded current federal climate policy settings would not allow Australia to meet its emissions reduction targets under the Paris agreement.
Continue reading...Great Barrier Reef not likely to survive if warming trend continues, says report
Report projects by 2050 more than 98% of coral reefs will be afflicted by ‘bleaching-level thermal stress’ each year
The Great Barrier Reef will not survive coral bleaching if current sea temperature trends continue, according to a new report charting increases over the past three decades which blames manmade climate change for the problem.
The study found thermal stress to coral reef areas was three times more likely when its investigation finished in 2012 compared with when it began in 1985, forecasting “more frequent and more severe” bleaching through the middle of this century.
Continue reading...Black swan becomes black sheep in the mob
Langstone Harbour, Hampshire The black swan shrank back as the mute swans stomped up the mud bank towards us and jostled for a handout
The tide was out and as I approached the mill outflow I could see a black swan hunkered down on the exposed shingle. Native to Australia, black swans were introduced to Britain in 1791 as ornamental birds in captive wildfowl collections. Due to inevitable escapees and deliberate releases, sightings in the wild are widespread. Now, the number of breeding sites are increasing at such a rate that Cygnus atratus may be on the brink of establishing a self-sustaining population.
This was the fifth black swan to visit the creek in a fortnight and, as they often pair up during the winter months, it is likely that these birds were roaming in search of a mate. This swan didn’t sport the jet black velvet lustre of mature adult plumage – its sooty feathers had a charcoal grey cast and were fringed with taupe, which gave it an almost scaly appearance.
Continue reading...Independent Review into the Future Security of the National Electricity Market - Preliminary Report
Sex lives of reptiles could leave them vulnerable to climate change
We are only just starting to appreciate the full sexual diversity of animals. What we are learning is helping us understand evolution and how animals will cope with a changing world.
In humans and other mammals, sex chromosomes (the Xs and Ys) determine physical sex. But in reptiles, sometimes sex chromosomes do not match physical sex. We call this “sex reversal”.
Environmental factors such as temperature can trigger sex reversal in reptiles. In our recent study, we investigated how common sex reversal is in reptiles. We concluded that it is widespread and a powerful evolutionary force.
This raises important questions about how reptiles will survive in a warming world.
Xs and Ys, Ws and ZsIn humans, sex chromosomes determine if an embryo’s physical sex is either male (XY) or female (XX).
Reptile sex determination is more complicated. Some species, including snakes, use sex chromosomes like humans do. But in other species, such as crocodiles and marine turtles, sex is determined by the temperature the eggs are raised in.
We’ve recently come to realise that many species use a combination of both. When the temperature sends opposite signals to the embryo’s sex chromosomes, sex reversal is the result. For these lizards, the sex chromosomes don’t match their physical appearance and reproductive function.
The central bearded dragon (Pogona vitticeps) is probably the best-known example of reptile sex reversal. Its sex chromosomes are named Z and W.
Male dragons have two Z chromosomes and females have a Z and W. Female dragons normally produce roughly equal numbers of male (ZZ) and female (ZW) offspring. But when the eggs are incubated in a hot environment (greater than 32℃), more females than males hatch. Some of these females from hot nests are sex-reversed.
Sex-reversed females are fully functional. In fact they produce twice as many eggs as females with female sex chromosomes. This suggests that sex reversal might actually be an advantage in this species.
Another fairly well-understood example from Australia is the eastern three-lined skink (Bassiana duperreyi).
In this species males are XY and females are XX. Although these chromosomes share the same name, they aren’t the same as those found in humans. They have arisen independently and use different genes to trigger male and female development.
In this skink, females (XX) can reverse to males, but at cool incubation temperatures, a phenomenon we’ve observed both in the lab and in a wild alpine population.
In both species, the sex with matching sex chromosomes (ZZ males in the dragon and XX females in the skink) is the one that reverses. In dragons it happens at high temperatures, and in the skink at low temperatures.
Why reverse sex?Sex reversal can have major effects on the behaviour of an individual. Male-to-female central bearded dragons are bolder than males and females with matching sex chromosomes. This may help them find food and mates, but at the same time exposes them to predators.
Not all lizards lay eggs. Sex reversal caused by temperature is also thought to occur in species that give birth to live young, such as Tasmania’s snow skink (Niveoscincus ocellatus). In live bearers, sex reversal is caused by the environmental temperatures that a mother experiences during pregnancy.
We believe that sex reversal is widespread in reptiles. Emerging evidence suggests that environmentally induced sex reversal may also be common in fish and amphibians, playing a role in evolution of new species and having serious implications in rapidly changing environments.
We suspect the reason no one has yet fully appreciated the role of sex reversal in reptiles is because much research has focused on mammals and birds, where sex reversal is usually caused by mutations that affect gene expression during embryonic development. This has created the false impression that sex reversal is harmful to an individual.
Another reason is that many reptile species have sex chromosomes that are very difficult to tell apart. That makes instances of sex reversal very difficult to spot.
An obvious question of deep concern is whether climate change could cause extinction by reversing the sex of entire populations. For temperature-sensitive species like the bearded dragon, crocodiles and marine turtles, is the future a warmer world without males?
The answer will be different for each species. Reptile survival under climate change depends on the answer to several questions.
Can the species control when and where they nest? How quickly are environmental conditions changing? Can the temperature at which sex reversal occurs change?
Each species will face a unique path as we experience an uncertain and changing environment. Some paths will undoubtedly lead to extinction, but others may utilise flexibility in sex-determination strategies to survive.
This research was conducted at the Australian National Wildlife Collection CSIRO, in partnership with the Institute for Applied Ecology at the University of Canberra and the University of the Sunshine Coast.
Clare Holleley receives funding from the Australian Research Council and the Commonwealth Scientific and Industrial Research Organisation (CSIRO).
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