Category: Analysis

Source: The Conversation – UK – By Michelle Spear, Professor of Anatomy, University of Bristol

In the animal kingdom, penises can be spiked, split, corkscrewed – even detachable. They’re one of the most diverse structures in biology. The human penis is so uniform, it’s an anatomical outlier. Understanding why penises evolved, and why they differ so widely, also helps explain why humans have one at all.

Penises first evolved as a solution to one simple problem: how to achieve internal fertilisation.

The first animals lived in the sea before our ancestors started living on land half a billion years ago. Today, many aquatic animals still simply release sperm and eggs into the water. However, as organisms moved to land, a new mechanism was needed to transfer sperm into the female body – enter the penis.

But here’s the twist: not all land animals use one. Around 97% of bird species have no penis at all. Instead, they reproduce with a “cloacal kiss”. This is a brief contact between a single opening that serves the digestive, urinary and reproductive systems and through which sperm is transferred.

The cloacal kiss demands choreography. For most birds, mating success hinges on split-second timing, elaborate courtship and perfect physical alignment. Animals with penises have an anatomical shortcut. They can deliver sperm straight to the target, even if the encounter is brief or a bit clumsy.

So penises are just one solution among many. But once evolution settles on a penis, the possibilities multiply. It is a prime example of convergent evolution, where different, unrelated, lineages develop similar traits in response to similar pressures.

In some species, penis size is driven by environmental constraints and access to mates. The barnacle, a crustacean glued to a rock for life, has the longest penis relative to body size of any known animal (up to eight times its own length). This allows it to “fish” for mates in the surrounding water. For those that may be wondering, the largest penis, at 2.5-3 metres, belongs to the blue whale.

The banana slug is a hermaphrodite with a thick penis as long as its body, evolved for deep sperm placement to boost fertilisation chances. Sometimes it gets stuck during withdrawal, and the partner bites it off. But the slug normally heals and survives.

Penile structures are often adapted for sperm competition, which is when multiple males mate with the same female, and their sperm compete internally for fertilisation. In these species, the penis becomes a competitive tool.

The domestic cat, for instance, has backward-facing spines on its penis. These stimulate ovulation in the female, ensuring sperm meets a ready egg, but also discourage mating with other males by making withdrawal painful.

In bedbugs, males take it further. They use a dagger-like penis to stab through the abdominal wall and deposit sperm directly into the body cavity. This “traumatic insemination” gives the male a bypass route – but at significant cost to the female. It’s not typically deadly, but the injuries take time and energy to heal.

Nowhere is this evolutionary struggle more vivid than in ducks. Some species of male ducks have corkscrew-shaped penises that can extend in under half a second. This is a response to female ducks evolving highly convoluted vaginas with dead-end pockets and spirals that twist in the opposite direction. This is a textbook example of sexual antagonistic co-evolution, where male traits that increase fertilisation rates are countered by female traits that limit male control.

In many reptiles, evolution has solved the problem of mating posture, the physical position and alignment of the bodies during copulation, with a pair of reproductive tracts. Snakes and lizards have hemipenes – two separate organs, only one of which is used per copulation. This redundancy probably evolved for flexibility, allowing mating from either side, and may be an adaptation to maximise success in brief mating windows.

In mammals, the penis can be reinforced by a bone: the baculum. Found in species such as dogs, chimpanzees and walruses, it allows penetration without relying on blood pressure. This structural support is useful in species where mating is prolonged or where mechanical stimulation during copulation is needed to trigger ovulation, in awkward or extended couplings like those of walruses, and when female anatomy or behaviour favours longer copulation.

What do these penises tell us about humans?

Compared to this dazzling variety, the human penis seems almost conservative. But this simplicity is deceptive.

Unlike many other mammals, humans lack a baculum. Instead, erection relies on blood flow. This mechanism may reflect a shift from brief, frequent copulations typical of high-sperm-competition species, to longer, emotionally bonded pairings. In this type of pairing, a visible, hydraulically produced erection serves not only a reproductive function, but also acts as a signal of arousal and health.

Human penile shape may still reflect adaptations to sperm competition. Scientists think the slight flaring of the glans at the corona, a prominent anatomical border between the glans and the shaft, may displace rival sperm during intercourse. This is not unusual among mammals, but in humans it may be especially important because intercourse and ovulation are often not perfectly timed, giving more scope for sperm competition. Human sperm can survive in the female reproductive tract for up to five days.

The glans and the sensitive underside frenulum contain a high concentration of sensory nerve endings that make them particularly sensitive to touch. This heightened sensitivity is thought to provide not only pleasure, but also real-time feedback. It allows the penis to respond to subtle variations in movement, pressure and partner interaction. Such feedback may have played a role in enhancing mutual sexual engagement.

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Scientists ignored animal clitorises for centuries – now we’re discovering just how varied they are

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A 2011 genetic study published in Nature found that humans lost specific DNA sequences that control the development of penile spines – small, keratinised projections on the penis that in chimpanzees and macaques help increase friction and stimulate the female during mating. These spines probably increased stimulation and shortened copulatory duration. Their loss in humans may reflect a shift from competition to cooperation.

This ties into another crucial aspect of human reproductive evolution: concealed ovulation. Unlike many mammals, human females do not advertise their fertility. In response, males evolved a strategy based on sustained sexual access, emotional connection and mate guarding.

The human penis is not just a reproductive organ, but part of a broader behavioural system tied to trust, intimacy and long-term partnership.

Michelle Spear 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 their academic appointment.

– ref. The surprising world of animal penises and what they reveal about humans – https://theconversation.com/the-surprising-world-of-animal-penises-and-what-they-reveal-about-humans-261690

Source: The Conversation – UK – By Punita Chowbey, Senior research fellow, Sheffield Hallam University

Economic abuse may not be as obvious as physical abuse, but for the millions of people it affects in the UK, economic abuse can be totally devastating.

Economic abuse, which is recognised as a form of domestic abuse in law, involves controlling a person’s (often a woman’s) ability to acquire, use and maintain economic resources.

Separating or divorcing does not mean the end of economic abuse in a marriage, particularly when children are involved. Post-separation economic abuse is often related to child maintenance or spousal support payments, which may be manipulated or withheld by abusers.

This harms mothers’ financial independence, mental health and parenting, and has consequences for children’s wellbeing.

A recent national survey found that minority ethnic women face economic abuse at twice the rate of white women (29% vs 13%). Our recently-published research explores why, through the experiences of 28 separated or divorced British south Asian Muslim women. This research is part of our continuing research on divorce and economic abuse.

Two-thirds of our participants had been financially dependent upon their husbands during their marriages, in keeping with broader statistics on the low employment rates of British Pakistani and Bangladeshi women. Further, several participants described their husbands preventing them from working.

UK-born Afsana had to work secretly as a tutor for meagre pay: “This tutoring was undercover with my dad. My working would have looked bad on [my husband].”

After separation or divorce, women were left economically vulnerable. Some struggled to find work, due to lack of recent employment experience as well as labour market discrimination.

“I worked in one school as a volunteer, but the Jobcentre said ‘that’s not enough, we need more evidence of work,’” said one woman. “I said, ‘everywhere you apply, they ask for a qualification, and experience is the main thing.’ I was not going out … how could I have undertaken any work?”

A major theme in our research was how abusers used child maintenance as a means to control women economically. In 18 cases, the father was not paying any child maintenance. Of the rest, only two mothers felt that the amount paid was fair.

Many women described child maintenance mirroring earlier patterns of economic abuse during their marriages. As UK-born Afsana put it: “He didn’t provide when he was with me, so I didn’t expect him to provide when he was not with me.”

Where women had involved the Child Maintenance Service (CMS), they felt it was unresponsive, especially those in transnational marriages involving economic assets overseas.

UK-born Kiran described her experience with CMS after her ex-husband hid assets in Pakistan: “I’ve even given the telephone numbers and addresses in the properties which are in Pakistan. [But] ‘Excuse me. We know that you’re upset. It just takes a bit of time.’ I go, ‘How long does it need?’”

Women felt disbelieved, which undermined their confidence in the system. Although the CMS may face limits in investigating finances held overseas, women felt the evidence they provided was often ignored. Many of the men were in self-employment, which may have made it difficult for the CMS to investigate.

Legal blind spots and immigration abuse

Post-separation economic abuse can also occur through institutions like courts and banks. UK-born Hora described how her husband remarried via an unregistered Islamic marriage, which allowed him to transfer money and assets to his new wife.

She told us: “My barrister said, ‘You’re not divorced from this lady yet, but you’ve remarried.’ He said, ‘Yes judge, in my religion I can have four wives.’ And this is a High Court judge, and he said, ‘Yes, quite!’”

Hora felt that this comment suggested the judge supported her husband’s use of religious justification for re-marrying before divorce, rather than recognising it as part of financial abuse.

Women with an insecure immigration status might also experience “immigration abuse”. This too can be a form of economic abuse, where, for example, an abuser uses the threat of deportation or immigration enforcement to trap women in financially dependent relationships.

Several women described struggling to open a bank account or obtain credit due to their migration status being exploited by their abusers. Pakistan-born divorcee Fauzia had never had a national insurance number, child benefit or bank account until these were arranged for her by a social worker at the women’s refuge she turned to with her children.

Our research suggests that south Asian women can face severe post-separation economic abuse due to multiple, intersecting disadvantages across the home, labour market and state institutions. Addressing these inequalities requires policies that take women seriously, while also being culturally sensitive and aware of the multiple challenges these women face.

Punita Chowbey receives funding from the NIHR, UKRI and Joseph Rowntree Foundation. Punita works closely with charities working on gender based violence.

Kaveri Qureshi receives funding from the NIHR and the ESRC. Kaveri Qureshi works closely with charities working on gender violence.

– ref. Minority ethnic women in the UK face economic abuse at twice the rate of white women. These are their experiences – https://theconversation.com/minority-ethnic-women-in-the-uk-face-economic-abuse-at-twice-the-rate-of-white-women-these-are-their-experiences-267263

Source: The Conversation – UK – By David C. Gaze, Senior Lecturer in Chemical Pathology, University of Westminster

Most of us think of orange juice as a simple breakfast habit, something you pour without much thought. Yet scientists are discovering that this everyday drink may be doing far more in the body than quenching thirst.

A recent study has shown that regular orange juice consumption can influence the activity of thousands of genes inside our immune cells. Many of these genes help control blood pressure, calm inflammation and manage the way the body processes sugar, all of which play an important role in long-term heart health.

The study followed adults who drank 500ml of pure pasteurised orange juice every day for two months. After 60 days, many genes associated with inflammation and higher blood pressure had become less active.

These included NAMPT, IL6, IL1B and NLRP3, which usually switch on when the body is under stress. Another gene known as SGK1, which affects the kidneys’ ability to hold onto sodium (salt), also became less active.

Such changes match previous findings that daily orange juice drinking can reduce blood pressure in young adults.

This is noteworthy because it offers a possible explanation for why orange juice has been linked to better heart health in several trials. The new work shows that the drink does not simply raise blood sugar. Instead, it appears to trigger small shifts in the body’s regulatory systems that reduce inflammation and help blood vessels relax.

Natural compounds in oranges, particularly hesperidin, a citrus flavonoid known for its antioxidant and anti-inflammatory effects, seem to influence processes related to high blood pressure, cholesterol balance and the way the body handles sugar.

The response also varies by body size. People carrying more weight tended to show greater changes in genes involved in fat metabolism, while leaner volunteers showed stronger effects on inflammation.

A systematic review of controlled trials involving 639 participants from 15 studies found that regular orange juice consumption lowered insulin resistance and blood cholesterol levels. Insulin resistance is a key feature of pre-diabetes, and high cholesterol is an established risk factor for heart disease.

Another analysis focusing on overweight and obese adults found small reductions in systolic blood pressure and increases in high density lipoprotein (HDL), often called the good cholesterol, after several weeks of daily orange juice consumption. Although these changes are modest, even slight improvements in blood pressure and cholesterol can make a meaningful difference when maintained over many years.

More clues come from studies that examine metabolites, the tiny molecules produced as the body processes food. A recent review found that orange juice influences pathways related to energy use, communication between cells and inflammation. It may also affect the gut microbiome, which is increasingly understood to play a role in heart health.

One study showed that drinking blood orange juice for a month increased the number of gut bacteria that produce short-chain fatty acids. These compounds help maintain healthy blood pressure and reduce inflammation. Volunteers also showed improved blood sugar control and lower levels of inflammatory markers.

People with metabolic syndrome, a cluster of risk factors that includes high blood pressure, raised blood sugar and excess body fat, may see particular benefits.

In one study, daily orange juice consumption improved the function of the lining of blood vessels, known as endothelial function, in 68 obese participants. Endothelial function describes how well blood vessels relax and widen, and better function is associated with a lower risk of heart attacks.

Not all studies report the same outcomes. A broader analysis of blood fat concentrations found that although levels of low density lipoprotein (LDL), often called the bad cholesterol, often fall, other lipid measurements such as triglycerides and HDL may not change much. Even so, people who regularly drink orange juice may still benefit.

A study of 129 workers in an orange juice factory in Brazil reported lower blood concentrations of apolipoprotein B, or apo-B, a marker that reflects the number of cholesterol-carrying particles linked to heart attack risk.

Altogether, the evidence challenges the idea that drinking citrus fruit juice is simply consuming sugar in a glass. Whole fruit remains the better choice because of its fibre, but a modest daily glass of pure orange juice appears to have effects that build up over time.

These include easing inflammation, supporting healthier blood flow and improving several blood markers linked to long-term heart health. It is a reminder that everyday foods can have more influence on the body than we might expect.

David C. Gaze 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 their academic appointment.

– ref. Your daily orange juice could be helping your heart – https://theconversation.com/your-daily-orange-juice-could-be-helping-your-heart-270492

Source: The Conversation – UK – By Vikram Niranjan, Assistant Professor in Public Health, School of Medicine, University of Limerick

As a public health dentist and researcher, for years I saw the same pattern. Patients with deep root infections often had wider health problems, particularly those with diabetes. I did not yet understand why. Now, scientific studies are beginning to explain the link: treating a deep tooth infection may also help the body manage blood sugar.

A tooth infection might seem like a relatively minor health issue, but its effects can reach far beyond the mouth. Recent research found that people who had root canal treatment for long-lasting infections at the root tip experienced lower blood sugar and reduced inflammation over the following two years.

The same pattern was also seen in a longitudinal metabolomic analysis, which is a type of investigation that tracks people over time and uses detailed blood tests to measure hundreds of small molecules that show how the body is functioning. It allows scientists to see how a treatment influences overall metabolism, not just the infected tooth.

The patients in the metabolic analysis had apical periodontitis, which is a deep infection around the very tip of a tooth root. It often causes no pain, so many people do not know they have it until it shows up on an X-ray.

Blood tests before and after treatment showed improvements in long-term blood sugar and markers linked to heart and metabolic health. Simply removing the infected tissue inside the tooth seemed to benefit the body far from the site of the infection.

One reason is that these infections do not always stay local. When bacteria reach the tissues around the tooth root, the immune system responds. If the infection persists, the body produces low-grade inflammation: a constant, simmering immune response that never fully switches off.

This type of background inflammation can spread through the bloodstream. It can make it harder for the body to regulate sugar effectively because chronic inflammationinterferes with how insulin works, reducing the body’s ability to move sugar out of the blood and into cells.

To understand how this local problem can spark body-wide effects, researchers have pulled the evidence together: a narrative review summarises findings from many studies and maps the biological pathways that may link apical periodontitis to wider systemic disease.

Oral infections and diabetes

Many studies have explored this connection between oral infections and diabetes, and these findings can be summarised more simply. A review of seven studies found that people with diabetes are more likely to have persistent lesions around root-treated teeth.

In this case, it is diabetes that increases the risk of slow healing – not the other way around. High blood sugar weakens the immune response and disrupts bone repair, so lesions at the tip of the root (seen on X-rays as darker areas where bone has not healed properly) are more common.

Another review found that people with diabetes also face a higher risk of developing new apical periodontitis in root-filled teeth compared with people without diabetes. A clinical study involving hundreds of root-filled teeth reported the same trend.

Patients with diabetes had more persistent lesions than those without, reflecting poorer glycaemic control – meaning blood sugar levels remain consistently higher than recommended, something known to slow healing throughout the body, including in bone and connective tissue.

More information on this connection can be found in clinical guidelines from diabetes and oral-health organisations, and in research on wound healing and glycaemic control, which all highlight how high blood sugar impairs immune function and tissue repair.

Researchers are now studying what happens when these infections are treated successfully. One study using detailed metabolic testing found that root canal therapy not only resolved the infection but also led to better blood sugar control and reductions in inflammatory markers.

Root canal treatment removes the infected tissue and seals the space, stopping bacteria and toxins from affecting surrounding tissues. Another study confirmed that while lesions in root-treated teeth heal more slowly in people with diabetes, they do improve once the infection is managed. Even gradual healing seems to benefit the body as a whole.

These findings echo what we know about gum disease. Treating gum infections can improve blood sugar control in people with diabetes, a relationship supported by studies showing that periodontal therapy – professional treatment to remove plaque, tartar and infection from below the gumline – modestly reduces HbA1c levels.

HbA1c is a measure of average blood sugar over several weeks, so even a small reduction indicates improved long-term glucose control. Scientists suggest that reducing chronic inflammation in the mouth may help the body regulate sugar more effectively.

What makes infections at the tip of the tooth root so interesting is how easy they are to miss. Unlike gum disease, which often causes pain, swelling, or bleeding, apical infections can exist silently, while inflammation quietly spreads through the body. Reviews of apical periodontitis emphasise how often it goes unnoticed.

None of this means that root canals are a treatment for diabetes. The changes observed in studies are moderate and depend on factors such as infection severity and overall health.

And researchers are clear that causality is not yet established, so more controlled trials are needed. But the research strongly suggests that oral health has a wider role in metabolic health than most people realise.

For people with diabetes or at risk of it, this connection matters. A painful tooth, or even one that simply feels different, could be more than a local problem.

These findings also highlight a bigger issue, which is that dental care and medical care are often treated as separate worlds. The research on root canal infections shows how closely linked they can be. A properly treated tooth can save more than a smile; it may contribute to better overall health.

Vikram Niranjan 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 their academic appointment.

– ref. Root canals and blood sugar: the connection you probably haven’t heard of – https://theconversation.com/root-canals-and-blood-sugar-the-connection-you-probably-havent-heard-of-270129

Source: The Conversation – UK – By Sabine Lee, Professor in Modern History, University of Birmingham

I was in Khartoum when the conflict started. Armed soldiers of Arabs came to our house and they wanted to loot groundnuts, but my mother resisted opening the door. Immediately, one soldier shot her. I screamed but three of the soldiers surrounded me. They grabbed me and I was taken behind a building where ten soldiers raped me. Nobody came to rescue me because my mom was already shot dead and neighbours ran away. After two days, when my mom was buried, I joined others to come to South Sudan.

This girl’s story was shared with us near the Aweil border crossing between South Sudan and Sudan, and it mirrors what we heard from many others. In the sweltering heat of July 2024 – and with mud underfoot and rainwater pooling along the road – South Sudanese members of our international team asked people to share stories about experiences of women and girls making the perilous journey between the two countries. The accounts they shared were harrowing, urgent, and clear.

We spoke with nearly 700 returnees and forced migrants – women and men, girls and boys – many of whom shared similar experiences of being terrorised by soldiers and armed militias on both sides of the Sudan civil war. The war has been tearing the country apart since 2023 and has led to the deaths of more than 150,000 people.

The struggle for power between Sudan’s army and a powerful paramilitary group, the Rapid Support Forces (RSF) has led to a famine and claims of a genocide in the western Darfur region. The RSF was formed in 2013 and has its origins in the notorious Janjaweed militia that fought rebels in Darfur, where they were accused of genocide and ethnic cleansing against the region’s non-Arab population. New reports about massacres and atrocities continue to emerge.

As the crisis deepens, our research has revealed that sexual and gender-based violence is a major driver of migration to South Sudan. Over half of our participants said it was the main reason they sought sanctuary across the border, with adolescent girls, aged 13 to 17, being far more likely to state that sexual violence was the reason they had to migrate.

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The research, which was recently published in Conflict and Health , uncovered multiple harrowing accounts of gang rapes and murder, some on children as young as 12.

What is happening in South Sudan and Sudan?

Since its independence in 2011, South Sudan has remained among the most fragile states globally, plagued by chronic political instability and humanitarian crises. Following internal divisions, a devastating civil war, fought largely along ethnic lines, erupted in 2013. This conflict resulted in nearly 400,000 deaths and an estimated 2.3 million people forcibly displaced, including 800,000 to Sudan. Another two million people were internally displaced within South Sudan, severely undermining state-building efforts. The country has remained on a knife-edge with the UN stating in October that it is on the brink of returning to all-out civil war.

The outbreak of war in Sudan in 2023 further exacerbated South Sudan’s fragilities and vulnerabilities, jeopardised peace efforts and worsened the existing humanitarian crisis. The Sudan conflict triggered a massive influx, this time with over 1.2 million refugees and returnees crossing into South Sudan – placing immense pressure on already overstretched resources and services.

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Read more:
Why has Sudan descended into mass slaughter? The answer goes far beyond simple ethnic conflict

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As of 2024, over 9.3 million people in South Sudan – more than 70% of the population – required humanitarian assistance, with 7.8 million facing acute food insecurity. Over 2.3 million children were at risk of malnutrition, with some regions nearing famine conditions.

Even before 2023, South Sudan was among the highest-ranking countries for sexual and gender-based violence globally, having the second-highest rates in Sub-Saharan Africa.

The border between Sudan and South Sudan has long been a corridor of cyclical displacement, shaped by decades of war, famine, and political instability. However, the scale and complexity of the current crisis has intensified vulnerabilities, particularly for women and girls. The effects have manifested in rape, sexual abuse, trafficking, and forced prostitution – on both sides of the border.

Fleeing sexual violence and terror

We focused our study on that border and the people who were fleeing through it. We used “sensemaking” methodology (based on the principle that storytelling is an intuitive way to convey complex information and helps people make sense of their experiences) to document what happened to women on their journeys and the risks they faced in the South Sudanese settlements. We had adopted a similar approach when examining accounts of sexual exploitation by UN peacekeepers in Haiti and DRC.

The fieldwork team – three female and three male researchers from the not-for-profit STEWARDWOMEN – worked on the border of Aweil North for two weeks to collect these stories. STEWARDWOMEN is a women-led South Sudanese organisation which aims to address violence against women, including sexual violence.

Our team collected 695 stories from 671 people. The vast majority were South Sudanese returning to a country they had once fled (98%), and most were women of child-bearing age (88%). Over half of the stories were first-person accounts of their own migration, while others were shared by men about their female relatives.

The aim was to make sure people felt safe and empowered to speak openly. Josephine Chandiru Drama, a South Sudanese human rights lawyer and former director of STEWARDWOMEN, said:

By inviting women and girls to share their migration experiences in their own words, the data collectors honoured their agency and voice. This approach fostered trust, reduced retraumatisation, and yielded richer, more authentic narratives that reflect the lived realities of displacement.

‘They took the girls by force’

While violence is forcing families to flee Sudan, the risk is not shared equally. Our findings show how adolescent girls are disproportionately at the greatest risk.

Girls face acute danger that families often can’t easily prevent. Armed groups raid homes and camps, abducting girls or seizing them on roads and at checkpoints. Girls are singled out and subjected to sexual harassment and rape.

Parents may try to travel in groups, change routes, or hide their daughters, but when men with guns stop a bus or enter a village at night, their protection options are limited. These risks intensify as poverty deepens and safe transport is scarce. These conditions leave girls visible, isolated, and at risk. One woman told us how they were attacked:

… the rebel car came towards us. They took the girls by force and they raped us, the men could not do anything to protect us. What hurts is raping you in open even when the men are seeing us … what the Arabs did to women and girls was terrible and it is not only me going through it.

Another woman shared a desperately traumatic story about the rape and murder of her daughter. She said:

My 12-year-old daughter was raped by a group of soldiers and died instantly. This is a very sad story to tell but I have to talk about it so that the world can know what happened to women and girls in Sudan … The soldiers then raped all the five girls … Unfortunately, my raped little daughter died on the roadside … It was such a painful moment …

Our data confirmed this terrifying reality. When we looked at the responses by age, a statistically significant pattern emerged: adolescent girls, aged 13 to 17, were far more likely than older women to state that sexual violence was the reason they had to migrate.

We asked participants to place the experience they shared on a spectrum: was sexual violence the reason for migrating, or did it happen because of migrating? For adolescent girls, the answers clustered overwhelmingly at one end: sexual violence was the trigger, not a consequence of the journey.

It is possible that among older women sexual violence has become somewhat normalised after surviving previous conflicts in the region, compounded by the fact that younger, unmarried girls are specifically targeted for abduction and forced marriage. One girl explained what happened to her sister:

As we travelled to look for safety in our motherland of South Sudan … all the women and girls were ordered out of the car… and were raped by a group of five soldiers. As an innocent young girl, my 15-year-old sister tried to resist […] and she was beaten badly, raped by all the five soldiers and then killed … We were ordered to leave, and my sister was no more.

‘I came here … to change my life’

One young woman – barely out of her teens – reported feeling ashamed and embarrassed, as she told us about how they were attacked while fleeing to South Sudan.

… we were suddenly attacked by the militia and I was among the eight girls to be abducted. I was raped by four repeatedly for two days … The rape made me miscarry a three-month old baby and I contracted syphilis.

While violence is not unexpected in war, when we analysed the stories, a stark pattern emerged: overall 53% of participants specifically identified sexual and gender-based violence as a major reason to flee, and across every age group it was the primary driver. For many, it wasn’t simply a consequence of war – it was the final straw in the decision to leave Sudan.

The stories brought this data to life. A mother recounted the death of her child along the migration route, a direct result of the violence they were escaping. One man described how his wife and daughter were abducted along the route, leaving him to care for four other children and wondering whether they were still alive. He said:

It pains me a lot because I don’t know whether they are alive. Information circulates that most of the women and girls who were abducted were mob raped and many died. Maybe my wife and her daughter are victims.

These stories, like those of countless other women and their families, illustrate clearly that sexual violence was not a mere background noise to war – it was indeed the breaking point that sent them on the road. As one woman told us, the sexual violence she feared prompted her family to migrate to South Sudan:

My husband was taken by the Rapid Support Forces and I was stabbed when I refused to be raped by those men, I even still have the scar. I came here [to South Sudan] to change my life.

In the Aweil North temporary settlement, Kiir Adem, the team found shocking conditions. Designed as a short-term shelter, prior to resettlement by the International Organization for Migration (IOM), many people had been there for three months or longer. Some had been registered as refugees or returnees, others had not. All were struggling to survive without adequate food or shelter, and with no access to desperately needed healthcare.

Chandiru Drama said: “Due to rampant looting and robbery along the journey, countless individuals reached their destination stripped of essentials – no food, no clothing, no supplies.”

The reality after crossing

After crossing the border to relative safety in South Sudan, returnees and refugees were met with a new set of struggles: lack of infrastructure, limited access to medical care, and few humanitarian provisions.

Unlike in better established reception centres along the border, Kiir Adem had little in the way of support. The nearest health centre was over two hours away by car, an often impossible journey for exhausted, injured women and girls who had been robbed of any money or supplies they had carried. One woman told us:

It took me six days to reach South Sudan border. At the border, I reported the rape case but no treatment was given to me. The IOM officials referred me to health facilities in Gok Marchar which is about 50km but it was very far that I couldn’t travel and I didn’t have money for transport.

It is crucial for survivors of rape to receive prophylactic treatments and other emergency sexual and reproductive healthcare as soon as possible post-assault. Some participants detailed devastating physical injuries resulting from sexual violence, and still others were pregnant when raped or became pregnant as a result of rape. In these cases, the lack of medical care may result in dire outcomes.

Returnees were left, in many cases, to piece together their own makeshift shelters and to forage for food in the forests. The area was prone to flooding, with researchers having to wade through water to get to people. One woman said:

I travelled to South Sudan in April 2024 with two children. I am now stranded with my children because my husband ran away when the Arabs were rampantly sexually assaulting women … I never know whether he is alive or not. There were two girls who were also abducted during the migration to South Sudan. I am now in the returnees camp sleeping in grass thatched huts, a lot of rain, no tents, no food.

When asked how often they struggle to make ends meet, over 80% of women and girls responded, “all the time or most of the time”. Informal settlements, like the one where we collected data, have been developed along the length of the Sudan-South Sudan border.

The porousness of the border, regular movement across the border in times of relative peace, and the difficulties accessing formal crossing points make it near-impossible to effectively channel displaced peoples through formal crossing points and into comparatively well-serviced settlements. Improved services, including transports to official settlements and for medical care, are urgently needed in the border region to meet the high needs of returnees wherever they are located.

Urgent response needed

There must now be a shift in humanitarian response – from reactive service provision to proactive, survivor-centred protection strategies. For example, NGOs should increase activities along known migration routes and along the border and humanitarian aid funding must be increased by donor governments. The UN peacekeeping mission could also increase protection of civilian activities in South Sudanese border regions, in partnership with South Sudanese civil society organisations.

Sexual violence is not simply collateral damage of the war in Sudan. For many girls and their families, it is the primary catalyst for flight. The pervasive threat of abduction and rape is a key driver of migration, shaping who flees, when they flee, and compelling women and girls to take the unimaginable risks for a chance of safety in South Sudan.

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Read more:
‘People who spent years saving lives are now struggling to survive’ – how we witnessed Trump’s USAID cuts devastate health programmes in Kenya

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Since our data collection in the summer of 2024, the situation in Sudan has not improved and the security context in South Sudan has worsened. On the southern side of the border, increased conflict between ethnically-based armed groups and an uptick in political tensions between President Salva Kiir and first Vice-President Riek Machar, including the house arrest and subsequent treason trial against Machar, have stoked fears of a possible return to war in South Sudan.

Combined with increased economic pressures and spillover effects from the war in Sudan, South Sudan’s political and security status is increasingly precarious. The risk of South Sudan returning to war increases the urgency with which returnees must be resettled and their immediate needs met. The risks of increased conflict and violence will disproportionately impact those who are already displaced and vulnerable. Legally trained NGO personnel could help here by advancing criminal investigations which in turn could inform service provision.

International law has also been very slow to react. It was only in October this year that judges at the International Criminal Court advanced the first conviction for war crimes and crimes against humanity committed in Darfur in 2003 and 2004. Victims and survivors of the current war should not have to wait more than 20 years for trials.

The international community should work with women’s organisations, Sudanese and South Sudanese lawyers and human rights defenders to advance justice now, in whatever way is possible.

This could include survivor-centred investigations and evidence gathering, community justice initiatives, and safe spaces for survivors to begin their healing.

Women-led civil society organisations are well placed to support the immediate needs of women and girls, but they need support. Funding cuts have hit these organisations hard around the world, with many at risk of shutting down.

Chandiru Drama added: “If civil society organisations are to continue performing their lifesaving work, they must be funded at scale. This is not just a funding issue – it’s a justice issue … Because in the face of unimaginable violence, these groups are not just service providers – they are lifelines.”

The women and girls we met were clear: sexual violence forced their decision to run. If they are to stop running, an urgent response is needed: resettlement, humanitarian support, and justice must be prioritised.

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Sabine Lee received funding from the XCEPT Cross-Border Research and the Cross-Border Conflict Evidence, Policy and Trends (XCEPT) research programme, which funded the research detailed herein.

Heather Tasker receives funding from the Social Science and Humanities Research Council (SSHRC), International Development Research Council (IDRC), and the XCEPT Cross-Border Research and the Cross-Border Conflict Evidence, Policy and Trends (XCEPT) research programme. XCEPT funded the research detailed herein.

Susan Bartels received funding from the Cross-Border Conflict Evidence, Policy and Trends (XCEPT) research programme, which funded the research presented in this article. She also receives funding from the Social Sciences and Humanities Research Council (SSHRC) and the Canadian Institutes of Health Research (CIHR).

– ref. ‘I have to talk about it so that the world can know what happened to women and girls in Sudan’ – rape and terror sparks mass migration – https://theconversation.com/i-have-to-talk-about-it-so-that-the-world-can-know-what-happened-to-women-and-girls-in-sudan-rape-and-terror-sparks-mass-migration-269456

Source: The Conversation – UK – By Edward Lavender, Postdoctoral Researcher, Aquatic Science, Swiss Federal Institute of Aquatic Science and Technology; Edinburgh Napier University

The development of miniaturised electronic tags that can be attached to animals has been one of the most spectacular developments for biology, environmental science and wildlife conservation in the 21st century.

In a new study published in the journal Science Advances, my colleagues and I unlocked new opportunities to track animals underwater, using advanced statistical techniques also adopted in military and aerospace contexts.

Animals are tracked all over the world: in deserts, grasslands, forests, rivers, lakes and oceans, from the Arctic to the Antarctic. Satellite-based tags, which transmit the locations of tagged animals, have been particularly important, providing an unprecedented “eye on life and planet”.

But reconstructing the movements of animals that live exclusively underwater without ever surfacing remains a great challenge.

Beneath the waves, satellite-based trackers don’t work because the transmissions can’t pass effectively through water. So scientists have to rely on indirect observations to study animal movements, like detections on hydrophones or animal-borne depth measurements.

In Scotland, we have spent over a decade studying the movements of the critically endangered flapper skate (Dipturus intermedius). Skates, and their close cousins the sharks, are an ancient and diverse group of animals. The flapper skate is the world’s largest skate.

Growing over two metres long and 100kg in weight, flapper skate can be found roaming in the darkness over the seabed in the north-east Atlantic. It’s thought they may live for over 40 years.

For generations, flapper skate was mislabelled as common skate. It was only in 2010 that the common skate was shown, genetically, to comprise two species: the flapper and the common blue skate. Both are thought to be critically endangered due to historical overfishing.

In 2016, the Loch Sunart to the Sound of Jura marine protected area in Scotland was established with fisheries restrictions to conserve flapper skate. It’s an inspiring place. The mountains of Scotland’s west coast rise dramatically out of the sea, which is peppered with islands and inlets. But the landscape is just as rugged underwater, where flapper skate roam in the deep.

Listening for animals underwater

Since 2016, we’ve been tracking flapper skate in Scotland using a technology called passive acoustic telemetry. It’s used in aquatic environments all over the world to track fish and other animals underwater. Animals are tagged with acoustic transmitters and networks of listening stations (hydrophones) are deployed that can detect those signals when tagged animals swim within range.

For flapper skate, we also deploy pressure sensors that record their depths. The challenge has been to integrate these different kinds of information to reconstruct individual movements, deep below the surface.

In our study, we took a step forward to solving this problem with a powerful statistical approach. It’s quite intuitive. We treat animals as “particles” that can swim around and reproduce or dwindle. Particles that move in ways that align with the data we collected are more prolific breeders and come to dominate the (digital) population. Similar techniques can be used in military tracking because the data updating step, which drives particle frequency, can happen in real time.

It’s just like building a sandcastle. We have a bunch of particles and the collection of all these particles forms a 3D map of an animal’s possible locations.

This is a great advance for conservation. By integrating information from multiple technologies into the algorithm, we can build up more detailed pictures of animal movements in the ocean. We can map their patterns of space use, work out how long they spend in particular habitats and use this information to inform conservation action.

For flapper skate, we found that they spend a remarkable amount of time in the protected area, so the fisheries restrictions there should support local recovery. We also identified specific hotspots beyond protected areas, where additional management may be beneficial. This work takes us another step towards targeted, data-driven conservation.

We’re now refining our methods and software implementations to reduce computing time. We’re also further developing our analyses to reconstruct detailed animal tracks, identify egg nurseries and build immersive virtual reality experiences of the lives of animals underwater. There is still much more to learn about animals in the deep.

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The study was funded by Eawag, using data made available via the Movement Ecology of Flapper Skate project. Data collection was funded by the Marine Directorate, NatureScot and the Marine Alliance for Science and Technology for Scotland.

– ref. Introducing a new way to track animals in the deep blue – https://theconversation.com/introducing-a-new-way-to-track-animals-in-the-deep-blue-270592