Macquarie University

Gender bending: baby turtles influence their own sex

Chinese-Australian research finds climate change good news, and solves an evolutionary mystery

Chinese Pond Turtle (Mauremys reevesii)
Image credit: Wikimedia Commons

Baby turtles influence their gender by moving around inside their eggs, research has revealed.

The idea that an embryo reptile can act in a way that affects its chances of developing as male or female has long been thought impossible, but findings by scientists from China and Australia have now provided clear proof of the process.

The research, published in the journal Current Biology, solves a long-standing evolutionary mystery – and offers hope that at least some species thought especially vulnerable to effects of climate change will prove more robust than thought.

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Aussie sharks still at risk from industrial fishing, despite protections

Macquarie University’s Professor Rob Harcourt urges Oceania-wide action to safeguard several species.

Sharks in Australian waters are well protected but are at risk as soon as they leave them, a new international study reveals.

The North Atlantic blue shark shares much of its territory with longline fishing fleets. Credit: Neil Hammerschlag

The study compiled by 150 scientists around the world – including 26 with ties to Australia – has found that even in the most remote parts of the world’s oceans migratory sharks are in severe danger from commercial fishing fleets, new research reveals.

In a paper published in the journal Nature, more than 150 scientists, including Professor Rob Harcourt from the Department of Biological Sciences at Australia’s Macquarie University, report that the sharks – which include iconic species such as the shortfin mako (Isurus oxyrinchus)  and the great white (Carcharodon carcharias) – congregate in food-rich areas that are also prime hunting grounds for commercial longline fishing fleets.

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Astronomer flies high to spy on star formation

Dr Stuart Ryder is venturing into the stratosphere on a NASA jet to study the birthplace of massive stars.

Macquarie University astronomer Dr Stuart Ryder is in New Zealand to hitch a ride on a NASA jet and take a closer look at how stars are born in one of the most active stellar nurseries ever seen.

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Baby blue-tongues are born smart

Australian research finds little lizards learn very quickly.

Young Australian eastern blue-tongue lizards (Tiliqua scincoides) are every bit as clever as adults, researchers have found.

Life is hard for baby blue-tongues. As soon as they are born, they are on their own, with neither parental support nor protection. Adults of the species can grow to 600 millimetres long and enjoy the benefits of thick scales and a powerful bite, but the young are much smaller and thus more vulnerable to predation.

And that means they have to box clever if they are to survive.

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Exiled moons may explain astronomical mysteries

Australian and South American researchers posit wandering “ploonets” as unseen actors in distant solar systems.

Moons ejected from orbits around gas giant exoplanets could explain several astronomical mysteries, an international team of astronomers suggests.

Researchers led by Mario Sucerquia, from the Universidad de Antioquia, Colombia, and Jaime Alvarado-Montes from Australia’s Macquarie University, modelled the likely behaviour of giant exomoons predicted to form around massive planets – and discovered that they would be expelled and sent packing.

Roughly 50% of these ejected moons would survive both the immediate expulsion and avoid any subsequent collision with the planet or the star, ending up as quasi-planets travelling around the host star, but in eccentric “Pluto-like” orbits.

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An island haven for frogs in a sea of extinctions

New Guinea is one of the only places in the world where frogs are safe from the species-destroying chytrid fungus. An international team of scientists has published a new paper that shows how to keep it that way, but they need help to carry out their plan.

The chytrid fungus has wiped out more than 90 frog species around the world, and it’s driving hundreds more towards extinction. New Guinea – the world’s largest tropical island, and home to 6% of all known frog species – is one of the last remaining refuges from the deadly infection.

A team of scientists led by researchers from Macquarie University and the University of New England in Australia think they know how to keep the island’s frogs safe, but they need support to establish a long-term program of monitoring and conservation.

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Earth recycles ocean floor into diamonds

Is the sparkler on your finger recycled seabed? Photo: Flickr CC/Stephen Durham

Most diamonds are made of cooked seabed.

The diamond on your finger is most likely made of recycled seabed cooked deep in the Earth.

Traces of salt trapped in many diamonds show the stones are formed from ancient seabeds that became buried deep beneath the Earth’s crust, according to new research led by Macquarie University geoscientists.

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More safe havens for native plants and animals needed in NSW’s west

The squirrel glider (Petaurus norfolcensis) is listed as a vulnerable species in New South Wales. Photo: Wikimedia CC/Brisbane City Council

Location matters for species struggling to survive under a changing climate.

A new study led by Macquarie University has found we need to provide more safe havens for wildlife and plant species to survive under climate change in New South Wales’ west.

Along the Great Dividing Range, the vulnerable spotted-tailed quoll will be forced to move into higher habitats as the climate changes, but can find sanctuary in protected areas like Kosciuszko National Park.

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It’s not just fish, plastic pollution harms the bacteria that help us breathe

Plastic pollution can harm both the micro and macro-organisms living in our oceans. Photo: Kevin Krejci

Ten per cent of the oxygen we breathe comes from just one kind of bacteria in the ocean.

Now laboratory tests have shown that these bacteria are susceptible to plastic pollution, according to a study published in Communications Biology tonight.

“We found that exposure to chemicals leaching from plastic pollution interfered with the growth, photosynthesis and oxygen production of Prochlorococcus, the ocean’s most abundant photosynthetic bacteria,” says lead author and Macquarie University researcher Dr Sasha Tetu.

“Now we’d like to explore if plastic pollution is having the same impact on these microbes in the ocean.”

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Building farms and towers at sea to feed and power the world

As partners in the $329 million Blue Economy CRC announced in Launceston

Chief investigators from Macquarie L-R: Dr Fatemeh Salehi, Professor Darren Bagnall, Dr Ming Li, Dr Rouzbeh Abbassi

Macquarie University engineers will develop new technologies for ocean infrastructure as part of the Blue Economy Cooperative Research Centre announced by Karen Andrews, the Minister for Industry, Science and Technology.

The Blue Economy CRC will drive an evolution in marine-based industries, unlocking enormous economic, environmental and technological benefits in aquaculture and renewable energy in Australia’s maritime zone.

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