Videos of men removing their eyelashes, by trimming or shaving, have been circulating on social media in recent weeks. This trend is based on the idea short eyelashes look more masculine.

Hair can tell us a lot about our social and cultural values. As the Canadian sociologist Anthony Synnott says, it can represent embedded ideas about biological sex, such as “opposite sexes have opposite hair” and “head hair and body hair are opposite”.

But do sex differences have any basis in biology? And what about the health risks of tampering with your lashes?

If the idea of a buzzing razor coming near your eyes makes you nervous, there’s good reason.

Does sex determine eyelash length?

Most warm-blooded animals have eyelashes. Human eyelashes begin to develop in the womb at around seven weeks and by six months they are fully formed.

Typically, we have 100 to 150 lashes on the upper eyelid that grow in two or three rows. There are half as many eyelashes on the lower lid.

Eyelash length is usually around one-third of the eye’s width. Lower lashes are shorter (6–8 millimetres) compared to the upper lashes (8–12mm).

The density, length, thickness and curl of eyelashes are determined by your genetics. But there is no evidence these anatomical differences are linked to sex.

This means the idea men “naturally” have short eyelashes – and women’s are longer, darker and thicker – is based in culture, not biology.

Regardless of your sex or gender, eyelashes serve several important functions.

What are eyelashes for?

Protection

Eyelashes provide a barrier against dust, debris, bugs, bacteria and chemicals (such as hairspray and deodorants), stopping them from entering the eyes.

Tears form a fluid film that covers the eye to keep it lubricated. Eyelashes also prevent air drying out this film.

From an aerodynamic point of view, medium-length lashes (8mm) are ideal for stopping the eye’s surface from drying out. Very short lashes can expose the surface to air, while very long lashes can channel more air flow towards it.

Eyelashes also shield our eyes from glare, reducing how much light enters the eye by up to 24%.

Sensation

Eyelashes are highly sensitive, so touching the eyelashes triggers a blink reflex that makes the eye shut. This protects it from unwanted materials.

Blinking also activates the release of tears and distributes them across the eyes’ surface.

Social interaction

Eyelashes help us communicate. Blinking slowly can signal attentiveness or flirtation – and eyelashes make this more appealing.

Wearing mascara or fake eyelashes emphasises the eyelashes and can make the eyes look larger and more expressive.

So, what if you don’t have eyelashes?

People can lose their eyelashes for various reasons.

For example, chemotherapy for cancer often results in hair loss – including eyelashes – as does alopecia, an autoimmune condition which causes the body to attack its own hair follicles.

Some people also pull out their eyelashes when they are anxious or stressed.

If you can’t stop this behaviour, and your eyelash loss is noticeable and affects day-to-day life, you may have a condition called trichotillomania.

The compulsion to cut or shave hair (rather than pull it out) is known as trichotemnomania.

If you’re worried, you should speak to your doctor to get support.

No matter how hair is lost, without eyelashes you will likely feel greater discomfort. More foreign particles can enter the eye – exposing you to greater risk of infection – and you will blink more to try to wash them away.

More air on the eyes’ surface can also make them feel dry and irritated.

Is removing eyelashes risky?

Putting sharp blades near your eyes means if you are bumped, slip, or even blink, you risk injury to the eyelid or cornea (the clear, dome-shaped covering at the front of your eyeball).

Anything that goes near your eye should be very clean. If blades aren’t sterile, bacteria can lead to blepharitis (eyelid inflammation) or conjunctivitis (“pink eye”).

Will shaved eyelashes grow back?

Yes. If eyelashes are trimmed or shaved, the hair bulb and follicle (the sac surrounding the hair) remains in the skin of the eyelid, allowing the hair to keep growing.

Eyelashes grow at an average rate of 0.12mm per day, or 3.6mm a month. It could take up to three or four months for your eyelashes to grow back to their typical length.

Shaving does not affect the length, thickness and darkness of your regrown eyelashes – these will grow back the same as before (unless there has been irreversible damage to the follicle itself).

Sex, gender, and eyelashes

Perceptions of sex and gender differences in eyelashes persist, thanks in part to social norms and media portrayals.

For example, a 2023 study from the United States surveyed 319 people (142 men and 177 women) of diverse ethnic backgrounds about eyelash length in women. Men and women of all backgrounds said images of female faces with no or short eyelashes were the least attractive, regardless of ethnicity.

Cartoon characters illustrate how deeply ingrained and socially constructed these gender differences are. Compare Minnie Mouse’s long, thick lashes with Mickey Mouse, who has none.

This is not a thing of the past, as the masculine- and feminine-presenting characters of a popular current children’s cartoon Miraculous: Tales of Ladybug & Cat Noir still demonstrate.

In reality, all bodies and features, including eyelashes, are naturally diverse.

Body autonomy means recognising that personal choices about appearance are valid and should be respected without judgement. But when altering your body, it’s important to also know the health risks.

Amanda Meyer, Senior Lecturer, Anatomy and Pathology, James Cook University and Monika Zimanyi, Associate Professor in Anatomy, James Cook University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Nicolas Cage has made a career from his highly entertaining scenery chewing. He follows a performance style he calls “Nouveau Shamanic” – an exaggerated form of method acting where he acts according to the character’s impulses. This allows for the wild, unpredictable outbursts his characters are known for.

Cage films are also usually about masculinity: its worst excesses, the parameters restricting it, and what ennobling versions of it might look like.

The Surfer, a new Australian feature film from Irish director Lorcan Finnegan, leans right into masculinity as a theme.

Our unnamed protagonist (Cage) is returning to his former Australian home from the United States. He is newly divorced, and trying to buy a beachside property to win back his family.

He takes his teenage son (Finn Little) for a surf near the property, but they are run off by an unfriendly pack of locals.

Returning alone to the beachside car park to make some calls, he is besieged there over the next several days by the same gang. They are led by a terrifying middle-aged Andrew Tate-esque influencer, Scally (Julian McMahon), who runs the beach like a combination of a frat bro party and wellness retreat.

The protagonist’s fast descent into dishevelled, dehydrated delirium as the group’s hazing escalates, fuels much of the first two acts.

Fish out of water

It is impossible to think of an actor other than Cage who could make a character like this so enjoyable to watch.

From the first moments, he seems pathetic: giving his uninterested teenage son metaphorical speeches about surfing, losing arguments on the phone with his broker and real estate agent, reeking of pomposity and desperation.

The sense of a man out of his depth is compounded by his Americanness contrasting with the particular brand of Australian masculinity the locals display. Both types are brash and entitled, but with entirely different ways of expressing it.

Cage’s distinctively American confidence has no resistance to the terrifying switches of Australian masculinity from friendly to teasing to violent.

“Don’t live here, don’t surf here,” they hiss at him on first meeting, forcing him to retreat, cowed, to the car park, where he remains for most of the rest of the film.

The wide-open and the claustrophobic

What a stroke of genius it is to use this single location.

Filmed in Yallingup, Western Australia, The Surfer beautifully captures the natural surroundings, stunning views and shimmering heat of Australian coastal summer.

At the same time, a confined, interstitial semi-urban feature like a beachside car park feels so bleak and uninviting. The only amenities are an overpriced coffee cart, ancient payphone and a dingy toilet block.

As a film setting, it is both a spectacular wide-open vista and stiflingly claustrophobic – a perfect mechanism for The Surfer’s psychological horror.

It must have been attractive in getting the script funded as well. With such an affordable location, more of the budget would have been freed up for a big name like Cage.

A modern Wake in Fright

With its oppressive setting, overexposed orange and yellow light and grade, and a sweaty spiral into madness, The Surfer invites comparisons to Wake in Fright, Ted Kotcheff’s 1971 brutal depiction of Australian men and their drinking culture.

Both take place at Christmas and feature an antagonist who enjoys confidently explaining their dubious moral worldview to everyone. However, Wake in Fright’s horror lingers because we know the culture remains even after the hero escapes it. The Surfer struggles a little more in landing the ending.

For the mean, violent, misogynistic villains to be defeated, it would be unsatisfying for Cage to stoop to their level. This means – without spoiling too much – Cage remains an oddly passive character throughout the film, while others perform the avenging actions.

The only way the protagonist’s masculinity can be resurrected as upright, ethical and empowering is for the character to literally turn his back on the vengeance we’ve been waiting for him to deliver.

It’s not that the film has an inarticulate grasp of its own politics, but more that the otherwise terrific script by Thomas Martin feels written into a difficult corner.

A blast along the way

I don’t want to imply that this ending means The Surfer isn’t an absolute blast along the way. A lot of the fun is in anticipating each dreadful humiliation – and it somehow turning out worse than you could have expected.

A spilled coffee leads to drinking recycled wastewater which leads to chewing on a dead rat, and we still haven’t reached the lowest rung on the ladder of indignities that Cage’s character suffers.

In less skilled hands this could feel nasty or gross, but the hallucinatory quality of Finnegan’s direction makes it feel almost sublime. And Cage’s pleading, groaning, sobbing and gibbering feel believable and relatable.

The pathos works – and it’s pretty funny too.

The Surfer is in cinemas from today and streaming on Stan from June 15.

Grace Russell, Lecturer, School of Media, Film and Journalism, Monash University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Think about how many things you have done online today. Paid a bill? Logged into your bank account? Used social media or spent time answering emails? Maybe you have used your phone to pay at a supermarket or train station.

We are all plugged in, and that’s not necessarily a bad thing. But with all these conveniences comes a growing risk many Australians are unprepared for: cyber crime.

According to the most recent cyber threat report by the Australian Cyber Security Centre, more than 87,000 reports of cybercrime were made in 2023-2024. That’s a report every six minutes. And that’s just what gets reported. Many people do not even realise they have been hacked or scammed until it’s too late.

Earlier this year, Scamwatch, run by the Australian Competition and Consumer Commission, revealed Australians lost nearly A$319 million to scams in 2024 alone. In a recent example, cyber criminals used stolen login details to hack several major superfunds in Australia and steal a collective A$500,000 of people’s retirement savings.

A big part of this worsening problem is poor “digital hygiene”. Here are five easy ways to improve yours.

First, what exactly is ‘digital hygiene’?

Just like brushing your teeth keeps cavities away, digital hygiene is all about keeping your online life clean, safe and protected from harm.

It is a simple idea: the better your habits when using technology, the harder it is for scammers or hackers to trick you or get access to your personal information.

It means being aware of what you are sharing, whom you are trusting, and how your devices are set up. Unfortunately, most of us are probably more hygienic in bathrooms than we are online.

How should you protect yourself?

Good news: you do not need to be a computer whizz to keep clean online. Here are five simple practical steps anyone can take:

1. Stop and think before clicking

Got an unexpected message from your bank asking you to verify your account? Or a text about a missed parcel delivery with a link? Scammers love urgency. It gets people to click before they think. Instead of rushing, pause.

Ask yourself: was I expecting this? Is the sender’s email or phone number legitimate? Do not click the link, go directly to the official website or app.

2. Use strong, unique passwords

Using your pet’s name or “123456” is not going to cut it. And if you reuse passwords across websites, a breach on one site means hackers can try the same password everywhere else. This is called a credential stuffing attack, and it is how the cyber attack on superannuation funds happened earlier this year.

The best move? Begin securing your online accounts by using a password manager and updating any reused passwords, prioritising your most sensitive accounts such as emails, banking and cloud storage first.

3. Turn on multi-factor authentication

Multi-factor authentication means you need something more than just a password to login, such as a code sent to your phone or an app such as Google Authenticator or Microsoft Authenticator.

It is a simple step that adds a powerful layer of protection. Even if someone guesses your password, they cannot log in without your second factor.

4. Update your apps and devices

Yes, those software updates are annoying, but they are important. Updates fix security holes that hackers can use. Make it automatic if you can, and do not ignore update prompts, especially for your operating systems such as Windows, iOS or Android. However, it is important to recognise that older devices often stop receiving updates because manufacturers stop supporting older models or are not developing updates for older devices as it can be costly.

Outdated software harbours known vulnerabilities that hackers actively can target. While keeping devices longer supports sustainability, there is a balance to strike. If your device no longer receives security updates, it may be safer to responsibly recycle it and invest in a newer supported model to maintain your digital safety.

5. Be mindful of what you share

Oversharing on social media makes you an easy target. Public posts that include your birthday, where you went to school, or your pet’s name can be used to guess security questions or build convincing fake messages. Think before you post – would a stranger need to know this?

What should I do if I have been hacked?

To check if your passwords have been leaked in a breach, you can use HaveIBeenPwned – a free tool trusted by security experts.

If you have been hacked, follow the tips provided by Australian Cyber Security Centre. For example, you should change all your passwords and passcodes and use software to scan for malware on your computer.

Need more help? Visit esafety.gov.au for practical guides, especially for parents, teachers and young people.

Digital hygiene is not a personal responsibility, it is a collective one. We are connected through emails, group chats, workplaces and social media. One weak link can put others at risk. Talk to your family and friends about the risk of scams and how to avoid them. The more we talk about this, the more normal and effective digital hygiene becomes.

Because just like washing your hands became second nature during the COVID-19 pandemic, keeping your online life clean should be a habit, not an afterthought.

Meena Jha, Head Technology and Pedagogy Cluster CML-NET, CQUniversity Australia

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Each year, between March and October, large amounts of brown seaweed called sargassum wash up on the shores of Caribbean islands – choking beaches, damaging marine life and threatening tourism and public health. But a number of local entrepreneurs are hoping the seaweed could create an economic opportunity.

From the coast of west Africa to the Caribbean Sea and the Gulf of Mexico, climate change is warming the temperature of the ocean. Seas are also becoming more acidic as water absorbs carbon dioxide. This all results in more intense growth of sargassum in the tropical Atlantic.

Small Caribbean nations are among the hardest hit. With 20 million tonnes of this seaweed washing up on the beaches in 2024, sargassum is fuelling an economic and public health crisis.

The piles of noxious seaweed on the Caribbean islands’ white sandy beaches are putting off visitors to these islands and probably dampening tourism revenues.

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The fishing sector is also suffering, with blooms of seaweed getting caught up in fishing nets, often ripping them due to the weight of the seaweed. This makes it hard for fishers to catch fish and make a living.

The sheer volume of sargassum left to decompose on land produces toxic fumes that have forced people on islands like Guadeloupe to leave their homes. These toxic fumes have been linked to serious health issues including respiratory infections, sleep apnoea and even preeclampsia (high blood pressure during pregnancy).

The sargassum problem is just one of many slow-onset events that are being exacerbated by climate change. But gradual changes get much less attention or resources to address the consequences than, say, alarming wildfires or flash floods.

Slow-onset events are also much harder to quantify than climate-change-induced extreme weather, such as worsening hurricanes or floods. Our team at ODI Global, a thinktank, recently published a study that estimated the cost of these at US$2,000 (£1,500) per person. Calculating the tourism lost each year due to seaweed inundation is trickier.

Despite these challenges, through small-scale, locally developed solutions, as well as government policies that support small businesses including helping them access climate finance, entrepreneurs can find sustainable solutions to help their populations thrive in an era of climate change.

Legena Henry, a lecturer at the University of the West Indies in Barbados, uses sargassum to produce a biofuel that can power cars. Johanan Dujon, the founder and chief executive of St. Lucia-based Algas Organics sells plant tonics made from sargassum and is trialling methods to convert sargassum into paper.

Meanwhile, other innovations are helping to minimise the impacts of sargassum in the region.

Andrés León, founder of SOS Carbon, a spin-off organisation from the mechanical engineering department at the Massachusetts Institute of Technology, has designed a boat-based harvester to collect sargassum at sea to stop it from beaching and causing damage onshore.

Some islands, such as Jamaica, are using early warning systems, typically used to predict hurricanes, to predict the ocean currents that might bring a bumper arrival of the seaweed to their shores. This could give fishers up to 30 days notice of just how bad the inundation will be.

Barriers to scale up

But while small businesses are emerging, turning them into larger enterprises across the region remains difficult. As usual, small island nations struggle to get funding because investors think the projects are too small and won’t make enough money.

As Legena Henry recently told us on the Small Island Big Picture podcast, spending a few million dollars (as opposed to a few hundred million dollars) can feel administratively cumbersome for funders as they often have limited administrative capacity and large sums of money to manage.

Another issue is ensuring the benefits from any sargassum solutions flow into the affected Caribbean islands to support local growth and economic development.

Several opportunities exist for small island nations to generate some income from sargassum. They could, for example, sell licences to permit companies to harvest sargassum within their exclusive economic zones, which can stretch around many islands for hundreds of nautical miles.

They can also sell licences to businesses trialling or operating new sargassum technologies within their exclusive economic zones — for example, SOS Carbon has a patent pending for technology designed to sink sargassum to the seabed to store carbon.

Will sargassum continue to be a nuisance, or could it be an important renewable natural resource? It’s not yet clear.

Ideally, as with other renewable natural resources in developing countries, small island nations that own the sargassum need to find ways to extract a fair share of the value from that ownership, as well as selling to external companies that come in, remove it and profit from it.

With tax incentives and low-cost finance for domestic innovators, small islands can manage and sell sargassum and then use the proceeds to develop climate resilience measures.

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Emily Wilkinson, Principal Research Fellow, ODI Global and Emma Tompkins, Professor of Geography, Environment & Development, University of Southampton

This article is republished from The Conversation under a Creative Commons license. Read the original article.

This year 80 people put on their waders, grabbed buckets and quadrats (square metal frames), and splashed through the clear shallow waters. Once they reached one of the many sampling locations, marked by miniature floats, they threw their quadrats into the shallow water, ready to collect all the sea life that landed inside their quadrats.

No one had any idea what they might find living on the seabed until they reached into the water. Nearby, kids peered down at the seabed using underwater scopes, grandparents chuckled as they returned for a second forage.

This citizen science project combines coastal ecology and gastronomy. Our groups returned to the sorting stations to identify, count, weigh and measure each bucket of creatures and algae. A typical bucket might contain four living Pacific oysters, nine dead, a brush-clawed shore crab, four folded sea squirts and a handful of snails.

Then, we sat down together to eat a gourmet oyster dinner, prepared by Denmark’s top chefs. Organised by a shellfish gastrotourism association called Danmarks Skaldyrshovedstad, this oyster hunt (Østerjagten 2025) is a new annual festival held at the Salling Sund Bridge in the Danish Limfjorden, a 110-mile strait of water in northern Denmark.

The invasive Pacific oysters people had collected from the seabed then went on to be shucked and cooked. They were served au gratin, with wild flavour combinations, ranging from blueberry and blue cheese to shavings of prosciutto with strawberries and lime.

Most people told us they came along because of the quirkiness of this event, and the promise of gourmet food. Less than one in five people stated their interest in marine research as their reason for joining. Nobody attended the event just for the science.

As a coastal change researcher, this result was exciting – we were reaching an audience that might not normally engage. Even after participating, many people didn’t feel like citizen scientists. But when asked what they had learnt, most recalled facts about coastal ecology, as well as new ways to cook oysters.

Eating aliens

Back to the basket sample contents. Pacific oyster, brush-clawed shore crab, folded sea squirts: none are native to the Limfjorden or Danish waters. So many people were shocked to find out that their baskets were full of invasive species – these “alien species” are non-native and can compete with the resident species for both food and space.

Despite an increase in the number of empty Pacific oysters shells we found this year compared to last (indicating more oyster deaths), temperatures are rising in this estuary system. This means that conditions are becoming more suitable for the Pacific oysters and the other invasive creatures, many of which originate in warmer waters.

All oysters provide ecosystem services; improving water quality, forming new habitats and protecting coastlines from erosion by reducing wave energy. As Pacific oysters are bigger, rougher, tougher and much faster growing than native European oysters, they can have a greater impact on the environment.

This, however, is not necessarily a good thing. As Pacific oysters take over European oyster and blue mussel beds, birds which once fed on these species are left without vital food sources. The thick shells mean they have no predators once they reach a certain size. Beach goers can also be affected as the razor-sharp shells occupy previously sandy bathing areas.

Farming of the Pacific oyster has been banned in Denmark since 1998, yet despite this measure, Pacific oyster beds are now widespread and prevalent across Denmark’s estuaries. A single oyster can release between 50 and 200 million eggs during a spawning event each year meaning it is impossible to control them.

While children were discovering the joy of sea squirts, other marine scientists and I could have tougher conversations with adults about climate change. We explained that warming temperatures are clearly visible in the here-and-now of local monitoring data.

The Limfjorden is made up of a series of fjords and islands in northern Denmark which link the North Sea to the Kattergat (the sea between Denmark and Sweden). This area is characterised by undisturbed coastlines and rolling hills, as well as some famous geological sites. It is a popular holiday destination for those that enjoy being in nature, some Danish hyggelig (comfort) and seafood.

But the Limfjorden is subject to numerous pressures: eutrophication (when extra nutrients in the water cause toxic algal blooms), changing climate, fishing, dumping of dredged materials and the arrival of invasive species. Its resilience to these may serve as an ecological bell weather for the rest of the world’s coasts.

Our event highlights how we’ll have to deal with environmental issues together. One feedback form still sits on my desk, the participant wrote in Danish: “Forskning er alle mands projekt og at det har effekt.” This translates to “research is everyone’s project and it has an effect”.

This edible approach offers a new way of communicating complex issues such as biodiversity and the introduction of alien species. Oyster hunt-style events such as this offer an excellent opportunity for scientists like us to provide some food for thought.

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Dominique Townsend, Visiting Researcher, School of Geography and Environmental Science, University of Southampton; Camille Saurel, Senior Researcher, Coastal Ecology, Technical University of Denmark, and Pedro Seabra Freitas, Senior Researcher in Coastal Ecology, Technical University of Denmark

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Tin was the critical mineral of the ancient world. It was essential to alloy with copper to make bronze, which for many centuries was the preferred metal for tools and weapons. Yet sources of tin are very scarce – and were especially so for the rapidly growing bronze age towns, cities and states around the eastern Mediterranean.

Though major tin deposits are found in western and central Europe and in central Asia, by far the richest and most accessible tin ores are in Cornwall and Devon in southwest Britain. Yet it has been difficult to prove that these British deposits were used as a source for people in the eastern Mediterranean. So for more than two centuries, archaeologists have debated about where bronze age societies obtained their tin.

In a new study published in the journal Antiquity, our team analysed the chemistry and different forms of particular elements in tin ores and artefacts from across Britain and Europe. These included tin ingots found at prehistoric shipwreck sites at Salcombe and Erme, southwest Britain, as well as in the Mediterranean.

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This revealed that tin ingots from three ancient shipwrecks discovered off the coast of Israel and one shipwreck found off the Mediterranean coast of France originated in southwest Britain. The shipwrecks found near Israel date to around 1300BC, while the wreck from France has been dated to around 600BC.

Small farming communities across Cornwall and Devon would have dug, washed, crushed and smelted the abundant tin ore from the alluvial deposits in the region. The heavy sand to gravel-sized tin ore is in a layer buried under soft layers of barren silt, sand and gravel.

The tin ore is eroded from hard rock mineral veins and deposited by streams and rivers. There was simply no need for any complex and difficult mining of hard rock here. The tin would then have been taken to coastal locations where it could be traded.

It’s probable that the tin was then moved by traders through France to the Mediterranean coast, where it was loaded onto ships. It would make its way through flourishing trade networks between the islands of Sardinia and Cyprus before reaching markets in the east Mediterranean. The tin’s value would have increased immensely as it progressed along this 2,485 mile (4,000km) journey.

Tin is the first commodity to have been exported across the entire European continent. It was produced and traded at a potentially vast scale, but is rarely found in archaeological sites due to corrosion. But what we do known is that by 1,300BC, virtually all of Europe and the Mediterranean had widespread and consistent access to bronze.

We know of more than 100 bronze age copper mines from Ireland to Israel and from Spain to the southern Urals in Russia. Yet these would have been just a small proportion of the copper mines active at the time.

Given that bronze was typically made from 90% copper and 10% tin, if the copper produced by each of these known mines had to be matched by 10% tin, then tens or even hundreds of tonnes of tin were being traded each year – perhaps across distances of thousands of miles.

The volume, consistency and frequency of the estimated scale in the tin trade is far larger than has been previously imagined and requires an entirely new perspective on what bronze age miners and merchants were able to achieve. It is no coincidence that it is around 1,300BC that technologies from the east, such as sophisticated systems for weighing items, as well as bronze swords, reached small farming communities living on the Atlantic coasts.

A millennium later, around 320BC, Pytheas the Greek, from Massalia (modern Marseilles), journeyed by land and sea to Britain, which was at the edge of the known world at the time. Pytheas wrote the earliest account describing the island and its inhabitants in a book which is now lost, but which has partially survived in snippets quoted by later classical authors.

Pytheas described how tin in southwest Britain was extracted and traded off a tidal island he called Ictis, before being taken across the sea and down the rivers of France to the mouth of the Rhone in only 30 days. In our research, we provide the first direct evidence for the tin trade Pytheas described. We show that tin from the Rochelongue shipwreck, off the south coast of France and dating to around 600BC, came from southwest Britain.

While we can establish the movement of tin across the seas, we know very little about the markets on land in which it was traded. We are now working with a team of archaeologists from Cornwall to excavate on the tidal island of St Michael’s Mount, which has long thought to have been the island of Ictis described by Pytheas.

A pan-continental tin trade continued in all periods after the bronze age and, in the absence of written records, our approach, using different methods of analysis, allows us to determine whether the tin came from Britain.

Historical records show that during the medieval period, tin from Cornwall and Devon enjoyed a virtual European monopoly, with production continuing until the last tin mine closed in 1998.

Today, tin is once again a critical and strategic mineral, this time for use in the electronics industry. As such it forms a vital part of the tools and weapons of the 21st century. Cornwall’s tin production is also set to soon restart, reviving a 4,000 year old industry.

Benjamin Roberts, Associate Professor in Later European Prehistory, Durham University and Alan Williams, Honorary Research Fellow, Department of Archaeology, Durham University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Looking for an example of how not to give a wedding speech? Try this. I was recently told an anecdote about guests at a wedding who became suspicious about the detached, cliched style of the groom’s speech, and the monotonous way it was read. Gathered at the reception afterwards, they asked ChatGPT to write a groom’s wedding speech. Bingo! The result was as good as identical.

Admittedly, whether you’re bride or groom, best man or chief bridesmaid, giving a wedding speech can be a scary prospect. But if you want to keep it personal and memorable, AI is not the answer.

So what is? You could do a lot worse than following the five canons of classical rhetoric, as recommended by the great practitioners of the ancient world, Cicero and Quintilian: invention, arrangement, style, memory and delivery.

1. Invention

The first canon of classical rhetoric is invention. That’s the process of discovering and developing the ideas you’ll use in your speech.

You can’t speak about everything, and no one likes a speech that drones on. Around ten minutes is all you need. That leaves you time for maybe six or seven events in the life of the person you’re talking about.

If you visualise those six or seven events, that will help you remember them. Is there a theme or characteristic that binds them together? Identify one or two, and use them to create a thread.

Good speakers often begin with a bit of a warm-up – maybe some light-hearted comments about the venue, or something in the news, or just a good joke. Plan to single out people in the audience for a mention or a laugh. Say something nice about the new family, or friendship groups you’ve discovered through the relationship.

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2. Arrangement

History is your best friend when it comes to arranging the order of your speech. The events you’ve chosen under “invention” happened in order of time. So lean on history and organise them chronologically.

Also, remember that many of the best wedding speeches often follow an arc from light to serious. You can make fun of your subject for a while, but nothing quite beats ending with love.

3. Style

This will vary depending on your role. Best men and chief bridesmaids traditionally skirt the boundaries of politeness, or sometimes go crashing through them (the worst best-man jokes are not repeatable here, nor anywhere else, and there’s no shortage of books dedicated to them).

Mostly you’ll be talking to a mixed audience. You can be a bit risqué without offending anyone (sexist jokes are not recommended). And because you’re likely to be talking to people you know, try to be informal – the “familiar style”, as it used to be called. That also means being personal. The speech has to sound like you.

4. Memory

The prospect of remembering a speech may feel daunting or impossible. But speaking without notes makes a huge difference to how you engage your audience.

Look into their eyes and they will be drawn in. The ancient Roman educator Quintilian was one among many orators to recommend visual analogues as a memory aid – often, the ground plan of a house, where a porch leads to a hall, which leads to a dining room, and so on. You populate each room with clues. They might be verbal or visual.

Anything that helps you lift your eyes from a script will increase your chances of getting the audience on your side.

5. Delivery

Calm your nerves by visualising the scene ahead of time. Most people visit their wedding venue before the big day, so take the opportunity to get used to the space, and then run it through in your head afterwards.

Try rehearsing the speech while you’re going for a walk. When it comes to the big day and the room is full, remember that you can’t speak directly to everyone. Instead, pick out maybe three or four people to focus on, in different parts of the room.

There are novel approaches and there are disasters. The double-act approach can work brilliantly, where bride and groom take turns to deliver a single speech, but it may need scripting. If the venue has the facilities, a slide show can work well. Picking out the various groups of families and friends and getting them to wave usually works as a good warmup.

When you get a laugh, ride it – start speaking again just as the laughter is dying down. Don’t wait for silence. If you get into a panic and can’t think of anything, just say you’re so happy that you’re speechless, and raise your glass for a toast.

David Roberts, Professor of English and University Orator, Birmingham City University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

In Inconvenient Women, Jacqueline Kent shines a spotlight on some of Australia’s most radical and influential writers.

For Kent, these iconic women were “inconvenient” in many ways. They pursued careers as journalists, poets and novelists at times when many women were relegated to the private sphere. They spoke out against injustices, despite the personal cost. They lived unconventional lives, personally and professionally. And they embodied alternative forms of womanhood.

Review: Inconvenient Women: Australian Radical Writers 1900-1970 – Jacqueline Kent (NewSouth)

The limits of the “wave” metaphor to categorise periods of feminist activism are well known. Kent explicitly seeks to recentre women who were in between the “waves” – that is, she is interested in those who came after the campaigns for women’s suffrage during the so-called “first wave”, but predated the revitalisation of Western feminism in the “second wave” of the 1970s.

These women writers clearly laid some important foundations for later feminist activists, especially those who called for more radical social upheaval.

The book’s subtitle – “Australian radical writers” – clarifies its focus. Kent does not explicitly discuss the criteria for inclusion, but it becomes clear that “radical” is shorthand for the most left-leaning women writers and activists in the first two thirds of the 20th century.

Accordingly, much of the book is preoccupied with tracing their varied engagement with political ideas and organisations. As Kent clarifies in the book’s first few pages: “These were all women who used their power with words in support of their beliefs, and to question and change elements of the world they knew.”

Kent makes it clear, however, that this is a “joint biography”, not a work of history or literary criticism. Inconvenient Women focuses on how these women lived and how their literary contributions were informed – and indeed made possible – by their more unorthodox ways of being and living, rather than on the writing itself.

Kent puts it this way:

All these women were brave. Common to them all were unquenchable curiosity, fearlessness and willingness to take risks – with their lives, with their relationships, with the work they did.

Challenging norms

Written in an engaging and accessible style for a broad audience, Kent’s ambitious group biography places these formidable women at the forefront of Australia’s literary, cultural and political history. Spanning a period of 70 years, Kent maps the cultural and political shifts that enabled and constrained these women writers. Their activism took different forms across different periods, but for all of them writing was a key tool in their political arsenal.

The book’s five-part structure is chronological. Part one covers Federation, the granting of suffrage, and the first world war. It discusses a number of 20th-century writers who honed their skills in the journalistic field before publishing award-winning and often controversial novels.

Kent begins with journalist, poet and novelist Mary Gilmore. For more than two decades, from 1908 to 1931, Gilmore used the Women’s Page in the socialist magazine Worker to advocate for a mother’s allowance, support women who wished to eschew marriage, and criticise Christianity for its assumptions about women’s innate inferiority.

These ideas challenged the gender norms of the day, though in other respects, as Kent shows, Gilmore did little to disrupt prevailing ideologies. She supported the White Australia policy, for example.

In this opening section, Kent introduces several other women who return at various points in the biography, including Katharine Susannah Prichard, Miles Franklin, Marjorie Barnard and New Zealand-born novelist Jean Devanny.

Kent reflects upon the barriers encountered by these pioneering women authors. Devanny’s 1926 novel The Butcher Shop, which condemned the subservience of women in marriage, was the first book to be banned in Australia. Other lesser-known women whose work “hovered at the border of what was acceptable” included Jean Campbell, Doris Kerr and Marjorie Clark, who wrote under the pseudonym “Georgia Rivers”.

Kent’s commitment to reevaluating women writers who have not been foregrounded in literary or cultural history, such as poet Marie Pitt, is laudable. However, some of these figures – Marion Knowles and Elinor Mordaunt (the pen name of Evelyn May Clowes), for example – are only given short paragraphs. This reclamation is an important feature of the book, and I wanted to read more about these historically marginalised women.

Political dangers

Inconvenient Women is well researched and given texture through a variety of sources, including correspondence between some of these writers. Kent establishes how the subversive politics of her subjects informed their lives and their writing, and provides important insights into the communities they formed.

Many of these women supported each other across their often lengthy careers. Examining the intricate webs of connection and fruitful collaborative relationships – such as that between Marjorie Barnard and Flora Eldershaw, which produced novels, plays, short stories and essays – Kent foregrounds the intimacies of those who moved in literary and left political circles across the 20th century. This is one of the strengths of a group biography as a way of reframing histories from which women have been excluded.

At times, the focus turns to key male figures, such as journalist and communist activist Egon Kisch and Guido Barrachi, who was integral to the establishment of the Australian Communist Party and romantically involved with women writers such as Lesbia Harford and Betty Roland. This can distract from the book’s professed goal, though I acknowledge Kent’s introductory comment that “men figure in this story, too, both as antagonists and supporters”.

The extent to which the women’s writing overtly engaged with political issues varied, as did their positions on communism. While Prichard and Christina Stead wholeheartedly endorsed it, writer and critic Nettie Palmer appeared more ambivalent.

The second part of Inconvenient Women covers visits to the Soviet Union in the 1930s by Roland, Prichard, and Pamela Travers, the Australian-born author of Mary Poppins. Later in the decade, Palmer and Stead travelled to Spain, becoming caught up in the civil war and the protests against fascism. For Palmer, the experience cemented the importance of art as a “weapon”.

Continuing the book’s interest in women who may have been overlooked, Kent shows how Australian war correspondents, such as Women’s Weekly reporter Adele “Tilly” Shelton-Smith and Lorraine Stumm from the Daily Mail in England, played an important role during this tumultuous time.

Communism, Kent remarks, “influenced the work of some of Australia’s best women writers, whether they followed the Party or not”. This left them in vulnerable positions when war broke out in 1939. The third section of Inconvenient Woman considers how they responded to the second world war, personally and professionally. For many of them, this meant dealing with censorship, state surveillance and police raids on their homes.

To be a supporter of the left in the 1930s and 1940s, especially as a woman, could come at grave cost. Police raided Prichard’s house; Devanny was also subject to surveillance. As evidence of the oppressive political climate, Kent discusses how Dymphna Cusack, a teacher in inner-city Sydney, was transferred to Bathurst after the publication of Jungfrau (1936), her controversial novel exploring female sexuality. There were dangers in transgressing social mores.

As Kent shows, surveillance continued into the 1950s. Writers were increasingly subject to monitoring by ASIO. This included those who had received grants from the Commonwealth Literary Fund, such as Kylie Tennant, who returned the money after conservative parliamentarian Bill Wentworth publicly labelled her a communist.

The difficulties of publishing in such an environment, especially for women, are brought into sharp relief throughout the book. In the fourth section, which covers the years 1945–60, Kent addresses the difficulties experienced by women seeking to engage with the androcentric publishing industry. This is exemplified by the protracted publication journey of Come in Spinner (1951), co-written by Cusack and Florence James, which won a prize as an unpublished manuscript in 1946, only for its publication deal to be withdrawn. It eventually appeared five years later in an expurgated version.

Kent also emphasises how these women sought to ensure that writing be taken seriously as a form of labour. Many were involved in establishing and maintaining writers’ organisations. Gilmore and journalist Connie Robertson set up the Society of Women Writers in 1925, which was followed a few years later by a broader association, the Fellowship of Australian Writers, with Gilmore again at the forefront. Women were highly active, too, in the Australian Society of Authors, established in 1963 and still thriving today.

A formidable legacy

Despite living unconventional lives, Kent suggests many of these writers were not overt in their feminism. Dorothy Hewett’s social realist novel Bobbin’ Up represents a shift in this regard. Published in 1959, it is closer to the burgeoning modern women’s movement than any other literary text considered in the book.

Given certain voices have historically been privileged over others, it is unsurprising that the majority of the women in this book are white and heterosexual. A little more reflection on the conditions that made their careers possible could have further illuminated how some “inconvenient” women in Australia, as elsewhere, have always been seen as more acceptable than others.

There is, nevertheless, an important discussion of Indigenous women writers and activists, including the poet Oodgeroo Noonuccal (Kath Walker) and the activist and writer Faith Bandler, in the book’s fifth and final section.

Inconvenient Women lacks a conclusion. Its account stops before the 1970s, a turbulent time of social and political change, when “inconvenient women” became more visible than at any other time in Australian history. Some additional gesturing towards subsequent developments might have given a stronger sense of how the foundations laid by these trailblazing women were built upon by second wave writers-as-activists, such as Germaine Greer and Anne Summers.

At different points in the book, I found myself wishing for further reflection on certain figures and the reception of their work. But this is a limitation of the group biography sub-genre rather than Kent’s writing. Inconvenient Women may function as an introduction for some readers, sparking curiosity about these remarkable women and a desire to seek out their books, plays and poems. For others, it might illuminate connections between these figures, or provide a deeper understanding of their cultural and historical contexts.

Whatever the case, Kent urges us to acknowledge and reconsider the legacy of these formidable Australian women. Each of them, in their own way, models what it is to be an “inconvenient” woman – something we certainly need now, perhaps more than ever.

Anthea Taylor, Associate Professor, Gender and Cultural Studies, University of Sydney

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Last week, Meta – the parent company of Facebook, Instagram, Threads and WhatsApp – unveiled a new “personal artificial intelligence (AI)”.

Powered by the Llama 4 language model, Meta AI is designed to assist, chat and engage in natural conversation. With its polished interface and fluid interactions, Meta AI might seem like just another entrant in the race to build smarter digital assistants.

But beneath its inviting exterior lies a crucial distinction that transforms the chatbot into a sophisticated data harvesting tool.

‘Built to get to know you’

“Meta AI is built to get to know you”, the company declared in its news announcement. Contrary to the friendly promise implied by the slogan, the reality is less reassuring.

The Washington Post columnist Geoffrey A. Fowler found that by default, Meta AI “kept a copy of everything”, and it took some effort to delete the app’s memory. Meta responded that the app provides “transparency and control” throughout and is no different to their other apps.

However, while competitors like Anthropic’s Claude operate on a subscription model that reflects a more careful approach to user privacy, Meta’s business model is firmly rooted in what it has always done best: collecting and monetising your personal data.

This distinction creates a troubling paradox. Chatbots are rapidly becoming digital confidants with whom we share professional challenges, health concerns and emotional struggles.

Recent research shows we are as likely to share intimate information with a chatbot as we are with fellow humans. The personal nature of these interactions makes them a gold mine for a company whose revenue depends on knowing everything about you.

Consider this potential scenario: a recent university graduate confides in Meta AI about their struggle with anxiety during job interviews. Within days, their Instagram feed fills with advertisements for anxiety medications and self-help books – despite them having never publicly posted about these concerns.

The cross-platform integration of Meta’s ecosystem of apps means your private conversations can seamlessly flow into their advertising machine to create user profiles with unprecedented detail and accuracy.

This is not science fiction. Meta’s extensive history of data privacy scandals – from Cambridge Analytica to the revelation that Facebook tracks users across the internet without their knowledge – demonstrates the company’s consistent prioritisation of data collection over user privacy.

What makes Meta AI particularly concerning is the depth and nature of what users might reveal in conversation compared to what they post publicly.

Open to manipulation

Rather than just a passive collector of information, a chatbot like Meta AI has the capability to become an active participant in manipulation. The implications extend beyond just seeing more relevant ads.

Imagine mentioning to the chatbot that you are feeling tired today, only to have it respond with: “Have you tried Brand X energy drinks? I’ve heard they’re particularly effective for afternoon fatigue.” This seemingly helpful suggestion could actually be a product placement, delivered without any indication that it’s sponsored content.

Such subtle nudges represent a new frontier in advertising that blurs the line between a helpful AI assistant and a corporate salesperson.

Unlike overt ads, recommendations mentioned in conversation carry the weight of trusted advice. And that advice would come from what many users will increasingly view as a digital “friend”.

A history of not prioritising safety

Meta has demonstrated a willingness to prioritise growth over safety when releasing new technology features. Recent reports reveal internal concerns at Meta, where staff members warned that the company’s rush to popularise its chatbot had “crossed ethical lines” by allowing Meta AI to engage in explicit romantic role-play, even with test users who claimed to be underage.

Such decisions reveal a reckless corporate culture, seemingly still driven by the original motto of moving fast and breaking things.

Now, imagine those same values applied to an AI that knows your deepest insecurities, health concerns and personal challenges – all while having the ability to subtly influence your decisions through conversational manipulation.

The potential for harm extends beyond individual consumers. While there’s no evidence that Meta AI is being used for manipulation, it has such capacity.

For example, the chatbot could become a tool for pushing political content or shaping public discourse through the algorithmic amplification of certain viewpoints. Meta has played a role in propagating misinformation in the past, and recently made the decision to discontinue fact-checking across its platforms.

The risk of chatbot-driven manipulation is also increased now that AI safety regulations are being scaled back in the United States.

Lack of privacy is a choice

AI assistants are not inherently harmful. Other companies protect user privacy by choosing to generate revenue primarily through subscriptions rather than data harvesting. Responsible AI can and does exist without compromising user welfare for corporate profit.

As AI becomes increasingly integrated into our daily lives, the choices companies make about business models and data practices will have profound implications.

Meta’s decision to offer a free AI chatbot while reportedly lowering safety guardrails sets a low ethical standard. By embracing its advertising-based business model for something as intimate as an AI companion, Meta has created not just a product, but a surveillance system that can extract unprecedented levels of personal information.

Before inviting Meta AI to become your digital confidant, consider the true cost of this “free” service. In an era where data has become the most valuable commodity, the price you pay might be far higher than you realise.

As the old adage goes, if you’re not paying for the product, you are the product – and Meta’s new chatbot might be the most sophisticated product harvester yet created.

When Meta AI says it is “built to get to know you”, we should take it at its word and proceed with appropriate caution.

Uri Gal, Professor in Business Information Systems, University of Sydney

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Medieval alchemists dreamed of transmuting lead into gold. Today, we know that lead and gold are different elements, and no amount of chemistry can turn one into the other.

But our modern knowledge tells us the basic difference between an atom of lead and an atom of gold: the lead atom contains exactly three more protons. So can we create a gold atom by simply pulling three protons out of a lead atom?

As it turns out, we can. But it’s not easy.

While smashing lead atoms into each other at extremely high speeds in an effort to mimic the state of the universe just after the Big Bang, physicists working on the ALICE experiment at the Large Hadron Collider in Switzerland incidentally produced small amounts of gold. Extremely small amounts, in fact: a total of some 29 trillionths of a gram.

How to steal a proton

Protons are found in the nucleus of an atom. How can they be pulled out?

Well, protons have an electric charge, which means an electric field can pull or push them around. Placing an atomic nucleus in an electric field could do it.

However, nuclei are held together by a very strong force with a very short range, imaginatively known as the strong nuclear force. This means an extremely powerful electric field is required to pull out protons – about a million times stronger than the electric fields that create lightning bolts in the atmosphere.

The way the scientists created this field was to fire beams of lead nuclei at each other at incredibly high speeds – almost the speed of light.

The magic of a near-miss

When the lead nuclei have a head-on collision, the strong nuclear force comes into play and they end up getting completely destroyed. But more commonly the nuclei have a near miss, and only affect each other via the electromagnetic force.

The strength of an electric field drops off very quickly as you move away from an object with an electric charge (such as a proton). But at very short distances, even a tiny charge can create a very strong field.

So when one lead nucleus just grazes past another, the electric field between them is huge. The rapidly changing field between the nuclei makes them vibrate and occasionally spit out some protons. If one of them spits out exactly three protons, the lead nucleus has turned into gold.

Counting protons

So if you have turned a lead atom into gold, how do you know? In the ALICE experiment, they use special detectors called zero-degree calorimeters to count the protons stripped out of the lead nuclei.

They can’t observe the gold nuclei themselves, so they only know about them indirectly.

The ALICE scientists calculate that, while they are colliding beams of lead nuclei, they produce about 89,000 gold nuclei per second. They also observed the production of other elements: thallium, which is what you get when you take one proton from lead, as well as mercury (two protons).

An alchemical nuisance

Once a lead nucleus has transformed by losing protons, it is no longer on the perfect orbit that keeps it circulating inside the vacuum beam pipe of the Large Hadron Collider. In a matter of microseconds it will collide with the walls.

This effect makes the beam less intense over time. So for scientists, the production of gold at the collider is in fact more of a nuisance than a blessing.

However, understanding this accidental alchemy is essential for making sense of experiments – and for designing the even bigger experiments of the future.

Ulrik Egede, Professor of Physics, Monash University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

There’s a blaze of light across the sky! A fireball is seen by thousands, and mobile phone and dashcam footage soon appears on social media.

But what have people just seen? A mix of social media hashtags suggests confusion about what has streaked overhead. Was it a Soviet Venus probe? Was it one of Elon Musk’s satellites or rockets? Was it a meteor? Was it a comet?

While these objects have some similarities, there are crucial differences that can help us work out what just passed over our heads.

Shooting stars, meteors and comets

Shooting stars can often be seen on dark, clear nights in the countryside as brief flashes of light travelling across the sky. Usually, they are gone in just a second or two.

Shooting “stars” are not stars, of course. They are produced by dust and pebbles burning up high in the atmosphere, typically above 50km in altitude. Comets are often a source of this dust, and regular showers of shooting stars happen when Earth travels through comets’ orbits.

Sometimes shooting stars burn with colours that reflect their composition – including iron, magnesium and calcium.

Meteors and shooting stars are actually the same thing. But when people talk about meteors, they often mean bigger and brighter events – bolides. Bolides result from rocks and boulders plunging into Earth’s atmosphere, resulting in bright flashes of light that can outshine all the stars and planets in the night sky.

Bolides can reach the lower atmosphere and sometimes produce audible sonic booms. Occasionally pieces of the bolide – meteorites – even make it to Earth’s surface.

While bolides can survive longer than shooting stars, they also don’t last for long. As they are initially travelling at tens of kilometres per second, they don’t take long to traverse the atmosphere.

The Chelyabinsk meteor, the largest bolide known to impact Earth in over a century, shone brightly for only 20 seconds or so.

If you see something blaze across the sky, it almost certainly isn’t a comet. Comets are so far away from us that their vast speeds are imperceptible to the human eye. Furthermore, while comets are sometimes depicted as fiery, their glow is more subtle.

Space junk

Maybe the bright flash you just saw was space junk? Perhaps. The number of orbital rocket launches and satellites has increased rapidly in recent years, and this has resulted in some spectacular reentries, which are often discarded rocket stages.

Like meteors, space junk travels at vast speeds as it travels through the atmosphere and it begins burning up spectacularly. Also like meteors, you can see colours indicative of the materials burning up, such as steel and aluminium. However, there are a few things that distinguish space junk from meteors.

When rockets and satellites are launched into orbit, they typically travel along paths that roughly follow Earth’s curvature. So when space junk begins to enter the atmosphere, it’s often travelling almost horizontally.

Space junk also travels at slower speeds than shooting stars and meteorites, entering Earth’s atmosphere at roughly 8km/s rather than tens of kilometres per second.

Because of these factors, space junk can take minutes to enter the atmosphere and travels hundreds of kilometres in the process. Over this time, the space junk will slow down and break up into pieces, and the more solidly constructed parts might make it down to Earth.

The slower pace of space junk fireballs gives people time to grab phones, take footage and post on social media, perhaps with a little colourful commentary added for good measure.

Rockets

While space junk can produce a light show, rockets can also put on amazing displays. If you happen to be near Cape Canaveral or Vandenberg Space Force Base in the United States, or Wairoa in Aotearoa New Zealand, then it’s not unexpected to see a rocket launch. You get smoke, flames and thundering noise.

But in other parts of the world you may get a different view of rockets.

Rockets that bring satellites into our orbit accelerate to 8km/s. As they do, they travel many hundreds of kilometres at over 100km altitude. American satellite launches often travel near the coast, passing major cities including Los Angeles.

As rockets approach orbit, they are more subtle than the flames and noise of liftoff. Rockets produce plumes of exhaust gases that rapidly and silently expand in the vacuum of space.

While these plumes are typically seen near launch sites, they can be visible elsewhere, too.

Sometimes rocket engines are ignited after reaching an initial orbit to boost satellites to higher orbits, send probes into the Solar System or slow rockets down for reentry. Rockets may also vent excess fuel into space, again producing plumes or spirals of gases. While not necessarily a common occurrence, these have been seen all over the world.

Do look up

There’s a lot to see in the night sky – the familiar Moon, stars and planets. But there’s the unexpected, too – something blazing across the sky in minutes or even mere seconds. While fireballs may be puzzling at first, they are often recognisable and we can figure out what we’ve just witnessed.

Have you had the good fortune to see a fireball for yourself? If not, pop outside on a clear dark night. Perhaps you will see something unexpected.

Michael J. I. Brown, Associate Professor in Astronomy, Monash University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Roughly 140 million to 100 million years ago, the piece of land that is modern day Australia was located much further south on Earth. In fact, what is now Victoria was once within the polar circle, up to 80 degrees south of the equator and shrouded in darkness for months at a time.

Despite these harsh conditions, dinosaurs thrived here, leaving behind evidence of their existence at various palaeontological sites.

For decades, scientists have come to these sites to study the rocks containing the bones of these ancient creatures in order to better understand them.

My new research with palynologist Barbara Wagstaff, published in Alcheringa, builds on existing knowledge by using plant fossils from bone-bearing sites in the region to explain how the forests these dinosaurs lived in evolved – and, for the first time, illustrating them in detail.

One of the warmest periods on Earth

The Early Cretaceous epoch – between roughly 140 million and 100 million years ago – represents one of the warmest periods in the last half a billion years of Earth’s history. The sustained warmth was a result of increased volcanic activity, which released large quantities of carbon dioxide levels into the atmosphere.

The sustained warmth resulted in no polar ice caps, high sea levels and flooded continents.

The geographic distribution of land masses was also very different back then. The supercontinent Gondwana, in which most of the southern continents we know today were clumped into a single landmass, had only just started to break apart. At the time, southernmost Australia was in the polar circle.

The dinosaurs that lived in this region are known as “polar dinosaurs”. They included small ornithopods (plant-eaters with beaks and cheeks full of teeth) and therapods (carnivorous and predatory dinosaurs).

Building a picture of ancient plants

For decades, palaeontologists have been studying rocks from Victorian sites. To establish the age of the recovered dinosaur bones, we’ve needed the expertise of palynologists – palaeontologists who study microscopic fossil spores and pollen produced by plants.

Palynologists identified key species that they dissolved out of rocks. They deduced the dinosaur bones ranged in age from 130 to 100 million years old.

At the same time they were carefully recording all the microscopic spores and pollen they saw in the slides to build a picture of the plants through the Early Cretaceous period.

A planet-altering transition

The transition from a world without flowers to one with flowers has fascinated scientists for centuries, most famously Charles Darwin who labelled them “an abominable mystery”. More importantly, it also forever changed our planet.

Shortly after their first appearance approximately 132 million years ago, albeit in the southern portion of the supercontinent Laurasia, we see an explosive radiation of flowering plants not only in our new record from Victoria, but also globally.

What fuelled the evolution and rapid global expansion of flowering plants that dominate the Australian landscape today?

Our new research suggests warmer conditions helped flowering plants migrate across the globe and colonise understorey habitats shortly after evolving. Increased competition also contributed to the turnover in understorey flora, with flowering plants outcompeting lycophytes in rapidly colonising braided river channels after flooding events.

The appearance of flowering plants in the landscape resulted in the extinction of numerous understorey plants (in particular ferns) with a long fossil record.

As a result, by 100 million years ago, the forests of Victoria included an open conifer-dominated forest canopy. The subcanopy beneath was made up of seed ferns and ferns. Flowering plants and ferns featured in the understorey, alongside liverworts, hornworts, lycophytes and sphagnum-like mosses.

Diversifying in a warming world

High carbon dioxide levels in the past made the planet warmer. This is consistent with what’s happening today. As a result of these warmer conditions cool-temperate forests thrived in the polar circle.

For flowering plants, the warmer conditions provided an opportunity to diversify in an increasingly warm world. However, not all plants adapted to the warming world, with many understorey floras, including ferns, becoming extinct.

The fossil record provides crucial insights into how life will respond to predicted future climate conditions because these have occurred before in Earth’s history.

Knowing this history is crucial to our response to the current climate change challenge.

Some exciting places to visit to see fossils in Australia include Eric the Red West dig site in the Otway Ranges, Inverloch’s Dinosaur Dreaming dig site in Victoria, the Dinosaur Trail along the Queensland towns of Hughenden, Richmond and Winton, and sauropod footprints in Western Australia at Gantheaume Point.

Vera Korasidis, Lecturer in Environmental Geoscience, The University of Melbourne

This article is republished from The Conversation under a Creative Commons license. Read the original article.