In the remote Qinghai-Tibetan Plateau, a rare fungus grows inside dead caterpillars. In traditional Chinese medicine, this parasitic fungus is prized for its purported medicinal effects. Known as Ophiocordyceps sinensis – colloquially, caterpillar fungus or “Himalayan gold” – it can fetch astronomical prices on the herbal medicine market: up to US$63,000 per pound.

Ophiocordyceps sinensis fungus is a parasite that targets the caterpillar that is the larva of the ghost moth. The process begins in late summer to early fall, when fungal spores infect the caterpillars. Over time, fungal filaments called mycelia slowly spread out and consume the caterpillars from within, turning them into hardened, mummified shells by winter. When spring arrives, the fungus enters its final stage: A grasslike fruiting body sprouts from the preserved caterpillar’s head and pushes up through the soil.

While many traditional Chinese/herbal medicine consumers are drawn to the fungus for its supposed health benefits, my interest lies in a darker side of its harvest: the deadly relationship between caterpillar fungus collection and lightning strikes. As a meteorologist, I study lightning and its impacts around the world. A few factors come together to make the situation on the Qinghai-Tibetan Plateau so dangerous.

A deadly harvest

People hunt for this fungus during late spring and summer, exactly when lightning strikes are most common in these mountains. Villagers often spend weeks scouring the rugged mountains for this precious resource, sometimes up to 16,400 feet (5 kilometers) above sea level. That’s an altitude of more than 3 miles.

At these heights, the weather can change in an instant, and there’s nowhere safe to hide from storms. While this area doesn’t get as many lightning strikes as some parts of Asia, it’s still dangerous enough to be a serious threat during these crucial harvesting months.

Tragically, caterpillar fungus hunting has led to at least 31 lightning-related deaths and another 58 lightning-related injuries in the past decade, according to the yearbooks of Chinese meteorological hazards (中国气象灾害年鉴) and government websites, including the China Meteorological Administration and the National Disaster Reduction Center of China.

In May 2022, seven villagers from China, including a young child, were killed by lightning while harvesting the fungus. The following year, three people from Nepal were injured by lightning when collecting the fungus and had to be rescued by helicopter after spending days stranded in the mountains.

In our recent study, my colleague Ronald Holle and I found that the population-weighted lightning fatality rates in the fungus-collection hotspots of Yushu and Garze counties, located in the Sichuan Province of China, are staggering – 10 to 20 times higher than the already elevated rates in China overall. These numbers are on par with some of the most lightning-prone regions of Africa, where there is little lightning-safe infrastructure or safety education.

But lightning isn’t the only threat these villagers face in the mountains. They could encounter hail, heavy rains, strong winds and other severe weather. The complex terrain makes weather patterns highly dramatic and unpredictable. Making things even worse, cellphone signals and other communication options are limited or nonexistent, leaving villagers cut off from weather hazard alerts.

They could also face threats from wild animals and risky mountain slopes. In one tragic case, a collector was struck by lightning and fell to his death on steep terrain. Medical care is rarely available. When accidents occur, it may be days before help arrives.

Why take the risk?

It all comes down to the high-risk, high-reward nature of caterpillar fungus collection.

For local villagers, the potential rewards of harvesting caterpillar fungus are significant. With limited income opportunities in this remote region, many see the fungus trade as their best hope for survival. They face a tough choice: risk their lives or sink into poverty.

Improving lightning safety education and infrastructure are important but far from easy. Any real change would take a lot of investment.

While the local government does organize some lightning safety education, these mountain communities are isolated and the information is often outdated. And there’s simply no practical way to install adequate lightning protection across the vast, rugged terrain where the fungus is collected.

A fragile pursuit

The environment is suffering, too. With so many people hunting for the fungus, they’re damaging the delicate mountain soil, cutting down trees for firewood and leaving trash at their camps.

Years of overharvesting have forced collectors to spend more time in the mountains to find enough fungus, increasing their exposure to lightning and the fungus’s decline. Scientists warn that if this aggressive harvesting continues, the fungus might disappear completely in the next few decades.

There might be some hope. Researchers are exploring ways to cultivate the fungus as a possible substitute for the wildly harvested variety. Meanwhile, governments in China, India, Nepal and Bhutan have implemented regulations to protect the sustainability of caterpillar fungus.

But any solution will need to address the underlying economic and educational inequities in this remote region, opening up new opportunities for these communities to make a living so they don’t need to risk their lives chasing “Himalayan gold.”

Daile Zhang is an assistant professor of Atmospheric Sciences, University of North Dakota. This article is republished from The Conversation.

A specimen of spiny mouse (Scolomys sp.), a species discovered on a Conservation International Rapid Assessment expedition into the Alto Mayo Landscape in Peru, is pictured, June 16, 2022.
| Photo Credit: Reuters

An “amphibious mouse” with partially webbed feet that eats aquatic insects was among 27 new species discovered during a 2022 expedition to Peru’s Amazon, according to Conservation International.

Scientists also discovered a spiny mouse, a squirrel, eight types of fish, three amphibians and 10 types of butterflies, Trond Larsen, head of Conservation International’s Rapid Assessment Program, told Reuters this week.

He added that another 48 species found by investigators were potentially new, but needed further study.

The new species were found in Alto Mayo, a protected area with several ecosystems, Indigenous territories and villages.

“Discovering so many new species of mammals and vertebrates is really incredible, especially in such a human-influenced landscape as Alto Mayo,” Larsen said.

The expedition between June and July 2022 was made up of 13 scientists plus local technicians and members of Indigenous groups.

“It was really fantastic to work so closely with the Awajun people. They have extensive traditional knowledge about the forests, animals and plants they live side-by-side with,” Larsen said.

Among the new species, Larsen highlighted the spiny mouse that has stiff fur, the amphibious mouse, and a dwarf squirrel that measures 14 cm (5.5 in).

“(The squirrel) fits so easily in the palm of your hand. Adorable and beautiful chestnut-brown color, very fast,” Larsen said. “It jumps quickly and hides in the trees.”

Another favorite discovery was the blob-headed fish, a type of armored catfish, he said.

A total of 2,046 species were recorded during the 38-day expedition using camera traps, bioacoustic sensors and DNA sampling. Among them, 49 were classified as threatened, including the yellow-tailed woolly monkey and the tree monkey.

Larsen said the discoveries reinforced the need to protect the area.

“Unless steps are taken now to safeguard these sites and help restore parts of the landscape … there’s a strong chance they won’t persist in the long term,” Larsen said.

In this photo released by the Mammoth Museum at the Russian North-Eastern Federal University on Monday, December 23, 2024, University’s Scientists show the remains of a 50,000-year-old baby mammoth uncovered by melting permafrost in Russia’s Siberia.
| Photo Credit: AP

Researchers in Siberia are conducting tests on a juvenile mammoth whose remarkably well-preserved remains were discovered in thawing permafrost after more than 50,000 years.

The creature, resembling a small elephant with a trunk, was recovered from the Batagaika crater, a huge depression more than 80 metres (260 feet) deep which is widening as a result of climate change.

The carcass, weighing more than 110 kg (240 pounds), was brought to the surface on an improvised stretcher, said Maxim Cherpasov, head of the Lazarev Mammoth Museum Laboratory in the city of Yakutsk.

He said the mammoth was probably a little over a year old when it died, but tests would enable the scientists to confirm this more accurately. The fact that its head and trunk had survived was particularly unusual.

“As a rule, the part that thaws out first, especially the trunk, is often eaten by modern predators or birds. Here, for example, even though the forelimbs have already been eaten, the head is remarkably well preserved,” Cherpasov told Reuters.

It is the latest of a series of spectacular discoveries in the Russian permafrost. Last month, scientists in the same vast northeastern region – known as Sakha or Yakutia – showed off the 32,000-year-old remains of a tiny sabre-toothed cat cub, while earlier this year a 44,000-year-old wolf carcass was uncovered.

Environmental researchers extract genetic material from a Chilean frog’s leg (Calyptocephalella gayi) in a wetland in the middle of a neighbourhood in the city of Quilpue, Chile, December 8, 2024.
| Photo Credit: Reuters

A giant frog species that hopped alongside dinosaurs and is considered a “living fossil” is now losing ground in its native Chile as climate change and human intervention damage its habitat.

The Calyptocephallela gayi, or Helmeted Water Toad, is one of the largest frogs in the world, growing up to over 30 cm (1 foot) in length and weighing up to 1 kg (2.2 lbs).

The amphibian has seen little genetic variation for millions of years, but now its future is at risk, scientists say.

“It’s sad that a species that managed to coexist with dinosaurs, that managed to resist a mass extinction, is now threatened by human beings,” said Melissa Cancino, a vetinarian and founder of Proyecto Anfibia, a group dedicated to amphibian research and education in Chile.

The Helmeted Water Toad’s environment spans from the northern region of Coquimbo to the southern island of Chiloe, but its population is suspected to have declined by at least 30% since 1990 and it is listed as “vulnerable” on the International Union for Conservation of Nature’s (IUCN) Red List.

Factors such as climate change, habitat interruption, environmental decline and pollution have all caused the Helmeted Water Toad’s numbers to dwindle, Cancino said. Poor water and waste management have also threatened the frog’s environment.

Matias Faundez, another member of Proyecto Anfibia, has seen the habitat degradation first hand.

“This estuary runs through the whole city, and has plenty of illegal run-offs,” he said as he waded through a stream outside of Valparaiso. “Even so, the frog manages to survive.”

This handout photo long exposure shot shows the flight of a flock of autonomous drones during an experiment near Budapest, Hungary, Thursday, Oct. 21, 2021.
| Photo Credit: AP

Moving in a dense cloud, like throngs of people walking across a crowded public square, 100 drones maneuver through the night sky in Hungary’s capital, the result of over a decade of research and experimentation that scientists believe could change the future of unmanned flight.

The behaviour of the swarm, made up of autonomous drones that make their own real-time decisions on collision avoidance and trajectory planning without pre-programming or centralised control, is guided by research the Hungarian scientists performed on the collective movements of creatures from the natural world.

“It’s very rare that you see some technology and you say it’s beautiful,” said Boldizsár Balázs, one of the researchers working on the project. “In its theoretical core it resembles nature. That’s why the drones themselves don’t need to be pretty, but what they do is pretty because it resembles natural swarming behavior.”

Drones have in recent years become a common sight in our skies: Companies like Amazon and FedEx have launched drone delivery services, hobbyists use them for aerial photography and groups of over 1,000 drones have been pre-programmed to deliver large-scale light shows.

But the scientists at the Eötvös Loránd University in Budapest have developed new models based on animal behavior that allow a large number of drones to travel autonomously, reacting in real time to their environment and each other as they coordinate individual routes and tasks in dense aerial traffic.

“This is the level we call decentralisation … After the drones are told what to do, we can switch off the ground control station, we can burn it or whatever, throw it away,” said Gábor Vásárhelyi, a senior researcher at the university’s Department of Biological Physics. “The drones will be able to do what they have to do just by communicating to each other.”

Using data they gathered by monitoring the behavior of pigeons in flight, the patterns of wild horses in the Great Hungarian Plain and other animal movements, they developed an algorithm that allows the drones to make on-board, autonomous decisions, safely mitigating conflicts and avoiding collisions.

While such technology has the potential to increase efficiency across many fields, some researchers have voiced concerns that certain applications of autonomous drones could pose significant dangers.

Anna Konert and Tomasz Balcerzak with the Faculty of Law and Administration at Lazarski University in Warsaw, Poland, have researched such risks, and warn that military applications could escalate arms races or be misused or hacked by malign actors such as terrorist groups.

“When drones take over lethal actions, responsibility may shift from human operators to machines, leading to uncertainty about who should be held accountable if errors occur,” they wrote in an email. “This detachment could lower the psychological barriers to initiating force, potentially making war more frequent and brutal.”

They also write that autonomous drones reducing the human cost of military engagements could “encourage more frequent military actions, leading to faster conflict escalation since fewer immediate human consequences would weigh against the decision to engage militarily.”

But beyond military uses, the researchers in Hungary say their technology has the potential to improve people’s lives through numerous other applications.

Their digital simulations in three dimensions have them convinced that their algorithm can be scaled up to support 5,000 drones flying together autonomously, which they say could have applications in meteorology, land surveying, goods deliveries and beyond.

The researchers are also working on rolling out an agricultural application that can be used for the precision spraying of crops, and believe the technology could also play a role in decentralising air traffic control systems as more and more unmanned aircraft take to the skies.

Many cultures associate twins with health and vitality, while others see them as a philosophical reminder of the duality of life and death, good and evil. 
| Photo Credit: Tesla Monson/The Conversation

Twins have been rare in human history and for that reason can seem special. Many cultures associate twins with health and vitality, while others see them as a philosophical reminder of the duality of life and death, good and evil. Some famous twins are credited with the birth of nations, others are described as deities.

Our recent research suggests that twins were actually the norm much further back in primate evolution, rather than an unusual occurrence worthy of note. Despite the fact that almost all primates today, including people, usually give birth to just one baby, our most recent common ancestor, which roamed North America about 60 million years ago, likely gave birth to twins as the standard.

We have been researching the evolution of primate litter size – how many babies grow during each pregnancy – for the past several years. To study mammal evolution and reproductive life history, we use skeletal collections, both fossil and recently living.

In addition to being an anthropologist, one of us (Tesla) is the mother of twin girls. That’s led to a personal and not just scientific interest in this topic: When did twin pregnancies become uncommon?

Reconstructing litter size in the past

The best way we have to reconstruct the history of litter size is to map the known litter size of as many species as possible across the mammalian family tree and then use mathematical algorithms to look for patterns. But outside of rare events where entire animal families are fossilized together, it is extraordinarily difficult to assess litter size for extinct species from the skeleton alone. So we instead collect data on as many living mammals as possible.

We searched a wide variety of public databases, including AnAge: The Animal Ageing and Longevity Database, for information about how many offspring are commonly born to each species of mammal. We also noted additional data, including what the species’ average body size is at birth and at adulthood, as well as pregnancy duration.

After gathering all these data points for almost a thousand mammal species, we performed a series of statistical tests to quantify relationships between different traits. Our goal was to estimate the likely litter size of different mammalian ancestors: What were the odds of a singleton birth for each species at any given point in time?

The number of offspring a species has in a litter is phylogenetically conserved, meaning more similar in more closely related species. Deer tend to have one or two offspring, while canids and felids tend to have many more babies in each litter.

Almost all primate species give birth to just one baby, although there are exceptions. Several of the wet-nosed primates – including lemurs, lorises and galagos – and almost all of the marmosets and tamarins from South America give birth to twins.

Prior to our work, researchers thought these distinctive twin-bearing primates must be what evolutionary biologists call derived, or different, from the more common, ancestral trait. But our research flips that narrative on its head: It’s actually the singleton-bearing primates that are derived and distinctive. Further back in evolution, two babies at once was the norm. Our ancient primate ancestors gave birth to twins.

So, when did this evolutionary change in primate litter size occur?

The switch to singletons

Modern humans overwhelmingly birth just a single child – a rather large child with an even larger head. Human brain and body size is certainly connected to our ability to create and refine technologies. Paleoanthropologists have long been investigating what they call encephalization: an increase in brain size relative to body size over evolutionary time.

For primates, and especially humans, childhood learning is crucial. We propose that the switch from twins to singletons was critical for the evolution of large human babies with large brains that were capable of complex learning as infants and young children.

Based on mathematical modeling, the switch to singletons occurred early on, at least 50 million years ago. From there, many primate lineages, including ours, evolved to have increasingly larger bodies and brains.

Our new research also shows that the switch from birthing twins to birthing singletons happened multiple times in the primate lineage – a telltale signal that it was advantageous for primates to develop only one fetus per pregnancy. Because multifetal gestation requires more energy from the mother, and because the babies are born smaller, and often earlier, early primate ancestors who gave birth to just one large offspring may have been at a survival advantage.

Our findings don’t mean that having twins today is a disadvantage – although, as a mother of multiples, Tesla can certainly say it’s not easy. But having twins today is quite a different experience from our tiny primate ancestors birthing in the trees 60 million years ago.

Twinning today

Rates of twins have almost doubled in the U.S. over the past 50 years, due in part to advances in assistive reproductive technologies. Today, about 3% of live births are twins, although recent trends suggest a downturn in rates. The fact that women in the U.S. are routinely having kids in their 30s compounds this even further, since women in the later stages of fertility – that’s anyone over the age of 35 – are more likely to have twins.

But having twins can be dangerous for both the mother and babies. More than half of all twins in the U.S. are born prematurely. Many of them spend time in the neonatal intensive care unit.

Despite these risks, our research shows that twins are a critical part of our genetic history.

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

In this Sept. 2, 2019 photo, a silverback mountain gorilla named Segasira walks in the Volcanoes National Park, Rwanda. The Spanish government has announced plans to ban harmful experiments on great apes as part of a wider initiative to give them increased rights closer to the ones humans enjoy.
| Photo Credit: AP

The Spanish government has announced plans to ban harmful experiments on great apes as part of a wider initiative to give them increased rights closer to the ones humans enjoy.

These plans are forward thinking compared with most of the rest of the world but the move is a double edged one. Bestowing human rights on great apes because of their similarity to us creates a new criteria – other animals can only be free of pain and suffering if researchers can prove they are human-like.

Great apes are the subset of non-human primates which include orangutans, gorillas, bonobos and chimpanzees. Over 16 years ago Spain first tried to grant great apes personhood. The cross party resolution was discussed but was never brought into law.

Currently, “unnecessary” experimentation is banned on great apes in 29 countries including the UK, the EU and New Zealand. This includes vivisection (surgery on a live body) or torture, depending on your attitude to the moral rights of great apes).

This may sound progressive. The problem is that “necessary” is defined in different ways. It usually focuses on crisis situations such as pandemics and epidemics, and in brain related research (primarily Alzheimer’s and brain trauma research) where many scientists argue the similarity of the great ape brain to humans makes it the only equivalent model. In 1999, New Zealand proposed bestowing human rights on great apes, but stopped short of doing so, instead banning all invasive experimentation on great apes.

The Balearic islands followed in 2008, and Austria is the only country in the world to have banned all live surgery on non-human primates, great and lesser (also known as gibbons, which include marmosets and baboons).

The Great Ape Project founded by moral philosophers Peter Singer and Paola Cavalieri, campaigns for the end of great ape experimentation. On its homepage are reminders of chimpanzees still incarcerated in laboratories, many of whom have spent their entire lives undergoing experimental procedures, such as the Alamogordo 26 in New Mexico. These 26 chimpanzees are still held at a laboratory, despite not being used in medical research for over two decades.

The question of human rights for great apes raises a number of issues, especially the way humans understand the natural world in a hierarchical structure. Humans are at the apex of this structure, and control the other levels of the hierarchy. This is known as speciesism. Who decides what is ethical for other species? Humans are one species, yet it is our perception which legislates the fate of all nonhuman animals.

Many animal rights activists refer to 18th century English philosopher Jeremy Bentham’s quote: “The question is not, ‘can they reason? nor, can they talk? But, Can they suffer?‘”. But this isn’t the main paradox when it comes to modern animal experimentation. Instead, it is the belief that the more similar to humans a nonhuman animal is, the more useful they are to research that affects humans. This would also mean their pain and suffering is more similar.

Great apes are good enough to act as models for human physiology, but don’t seem to be good enough to count as sentient, suffering beings. This is just as applicable to less human-looking animals. For example, labs patent strains of mice with DNA that reflects human cancers. This also makes them more likely to suffer as if they were human. So do we accept that mice are so similar they can model us in experiments but not so similar that their pain matters?

The second issue is that great apes reflect in their faces and their actions an elicitation of empathy, but not always for lesser apes. In February 2024 charity Animal Aid published the results of a Freedom of Information request about the experiments carried out at the University of Cambridge on lesser apes. In 2022, 68 experiments at the university involved primates, for example drilling holes into marmosets’ skulls and injecting a substance into their brains.

The UK also hosts a large beagle breeding facility, in Cambridgeshire, where the dogs may be force fed toxic chemicals to study the effects. Beagles are often used for animal experimentation due to their placid nature.

The lesser ape is not the human-faced great ape, but many of their actions and responses are human-like. For instance, female gibbons dance to attract a mate.

The idea of a beagle, a potential family pet, being bred for experimentation highlights the speciesism inherent in how we decide what or whom to become incensed about.

Because make no mistake, every animal is a who, not a what.

It may sound outrageous to make such a statement. How can a mouse be a who, you might ask. Mice are the most common species used in experiments, and are bred with genetic illnesses and deformities especially for the purpose. Isn’t the squeak of the mouse or the shriek of the monkey their own form of expression? Some experiments on rodents have been designed to “recapitulate the human pain condition”. The problem comes from human perception of the natural world and different species as existing only in relation to ourselves.

Animal activists often say “if slaughterhouses had glass walls the world would be vegan”. How would we feel if vivisection labs had glass walls?

Some scientists argue animal testing harms humans because of unreliable results. With alternatives available, from stem cell modelling to using AI in experiments and trials, as well as charities and research centres focused on animal free studies, maybe the onus should be on humans.

We should be asking, if humans are so technologically adept and progressive, why are our scientific methods so archaic, unreliable and unethical?

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

Many large mammals have lost genetic diversity, often thanks to the actions of people shrinking their populations. The implications can be severe because without genetic diversity, a population does not have a “genetic database” to fall back on to adapt to environmental change.

The Iberian lynx (Lynx pardinus) is no stranger to this reduction in diversity. Human activity has driven populations to dangerously low numbers, leaving them with a shrinking genetic pool. This loss threatens the lynx’s ability to adapt to changing environments, putting their survival at risk.

Our team’s research reveals how the Iberian lynx interbred with its cousin, the Eurasian lynx (Lynx lynx) over the past few thousand years. This mingling may have boosted the Iberian lynx’s genetic diversity. This is a crucial factor for its survival, especially as the species faces such an uncertain future.

Low genetic diversity can lead to “inbreeding depression”, where closely related animals breed and produce offspring that are less fit for survival. In extreme cases, this can push entire populations, or even species, to the brink of extinction.

To boost the genetic diversity of populations on the brink, conservationists sometimes turn to “genetic rescue”. This involves introducing individuals from different populations in the hope that they will breed with the local animals, reducing inbreeding and enhancing genetic diversity.

While this strategy can be effective, it’s not without risks. Introducing animals that are too genetically different can disrupt or dilute beneficial traits, potentially harming the population’s ability to survive and reproduce. It’s a phenomenon known as “outbreeding depression”. Despite these risks, genetic rescue remains a valuable tool in conservation, though it’s often approached with caution.

One of the most severe cases of reduced genetic diversity is the Iberian lynx, once the world’s most threatened cat species. It’s mostly found in parts of Spain and Portugal.

Rescue and recovery

Today, the Iberian lynx is recovering from near extinction. More than 400 reproductive females were reported in the 2023 census. This is a massive increase from just 25 in 2002. This turnaround is largely thanks to an ambitious conservation programme over the past two decades, involving coordinated breeding programmes and reintroductions.

Part of this success is due to the “genetic rescue” effect, where mixing the two remaining genetically distinct populations helped boost the species’ genetic diversity. Despite this progress, the Iberian lynx still faces significant challenges. The population is far from reaching the minimum of 1,100 reproductive females needed to be considered genetically viable. So, its genetic diversity remains one of the lowest ever recorded.

Further genetic rescue could be a solution to enhance diversity. But there’s a catch – no other Iberian lynx populations exist in the world that could serve as a source of new genetic material.

Ancient DNA can be extracted from historical remains or subfossil (animals that are not ancient enough to be considered true fossils but are not considered modern either) samples. By studying these, scientists can gain valuable insights into the genetic past of species, offering a stark comparison with their present day counterparts.

In 2015, our colleague Maria Lucena-Perez first visited the lab of another of our colleagues, Michael Hofreiter, in Germany to generate the very first whole genome data from ancient Iberian lynx bones. Extracting ancient DNA from bones is a highly specialised process that requires dedicated cleanroom facilities to prevent contamination from modern DNA.

Working together, our team successfully extracted nuclear DNA from three ancient Iberian lynx specimens. Two of these were approximately 2,500 years old. The third dated back more than 4,000 years. This marked the first time nuclear DNA had ever been retrieved from ancient Iberian lynx. Maria’s achievement has significantly advanced our understanding of how the genetic makeup of the Iberian lynx has evolved over thousands of years.

Our team analysed and compared the DNA with that of modern Iberian lynx. To our surprise, the ancient lynx showed even lower genetic diversity than their modern descendants. Given the sharp decline in their populations over the past few centuries, this finding was both unexpected and puzzling.

Species interbreeding

The missing piece of the puzzle came with the discovery that modern Iberian lynx populations share more genetic variants with the closely related Eurasian lynx than their ancient counterparts did. This suggests that the two species successfully interbred within the past 2,500 years, boosting the genetic diversity of today’s Iberian lynx.

These findings align with extensive genomic evidence of ancient gene flow from Eurasian lynx into the Iberian lynx genome. While the two species don’t share the same habitats today, they once coexisted in the Iberian Peninsula, and possibly in southern France and northern Italy. This situation would have provided plenty of opportunities for interbreeding.

The potential for these two species to naturally meet and breed is growing once more as their ranges continue to expand. This could open up new possibilities for genetic diversity in the future.

The advent of whole nuclear genome analysis over the past 30 years has revealed numerous cases of cross-species interbreeding, such as between polar bears and brown bears. This suggests that the case of the lynx is not so unusual. But the Iberian lynx stands out as the first documented example where interspecies breeding significantly increased species-wide genetic diversity.

We still don’t fully understand the exact effect of this genetic boost, particularly whether it improved the population’s fitness and survival. One intriguing possibility is that the Iberian lynx has managed to persist despite its extremely low genetic diversity, thanks to recurrent genetic rescues by the Eurasian lynx.

While there’s more to learn, our research offers an unexpected but important case study for the broader discussion on genetic rescue. If we can better predict the chances of inbreeding and outbreeding depression when interbreeding happens, we could use genetic rescue more effectively as a conservation tool in the ongoing biodiversity crisis.

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

A new study lifts the veil on what happens when octopuses and fish hunt together. As it turns out, this cross-species relationship is more complex than anyone expected.
| Photo Credit: The Hindu

A new study published in Nature Ecology & Evolution lifts the veil on what happens when octopuses and fish hunt together. As it turns out, this cross-species relationship is more complex than anyone expected.

Animals of the same species often cooperate – work together to reach some kind of goal. But it’s relatively rare to find cooperation between individuals from different species.

A classic example you’ll be familiar with is the close relationship between dogs and humans, whether in the context of herding sheep or hunting. In these situations, the dog and the human work together to achieve a goal.

That’s mammals. But underwater species also sometimes cooperate. A nice example is the joint hunting behaviour of moray eels and grouper. The grouper approaches the moray and signals that it wishes to hunt. The eel responds in kind, and off they go.

During these hunting forays, the grouper uses signals to indicate where prey may be hidden in the coral matrix. It’s a synergy made in heaven: the eel can scare the prey fish from hiding places among the coral, while the grouper patrols over the top. There is literally no place for prey to hide.

For the eels and grouper, the chances of catching their dinner are greatly improved when hunting together compared to hunting on their own.

Who’s in charge here?

While researchers have described these behaviours before, one question remains unanswered. Who, exactly, is in charge of these cross-species interactions?

Who decides what they are going to do, where and when? Are the different players “democratic”, in that they come to some form of compromise, or does one species take the lead and the other simply follows (that is, they are “despotic”)?

In an international collaboration, biologist Eduardo Sampaio and colleagues have investigated cross-species interactions between the usually solitary day octopus (Octopus cyanea) and several fish species, such as goatfish and groupers.

The fish and the octopus share a common goal – to increase their hunting efficiency. The traditional view of octopus-fish hunting groups assumed that the octopus is the producer, and the fish simply follow along and opportunistically pick up the scraps.

With its long, flexible arms, the octopus explores all the nooks and crannies of the hunting ground, flushing out prey the fish can then take advantage of. In this scenario, the octopus would be solely in charge of decisions and the fish just follow (that is, it’s an exploitative, despotic relationship).

However, when researchers took a closer look, it appeared perhaps this relationship is not as simplistic as previously believed. But without fine-scale analysis providing hard evidence, it is difficult to work out the precise details of how this cooperation works.

What did the new study find?

Using sophisticated behavioural analyses of 3D videos captured from 120 hours of diving, Sampaio and team found that each partner in the interaction plays a specific role. There was, in fact, no true leader – they are democratic.

The fish were responsible for exploring the environment and deciding where to move, while the octopus would decide if and when to move. Interestingly, controlled experiments showed the octopuses were guided by social information provided by the fishes.

When partnered with blue goatfish, the octopus foraging tactics where more focused and efficient. When partnered with blacktip groupers, they were less so. So, the nature of the hunting relationship varied depending on who’s involved.

The researchers concluded that, overall, success rates for capturing prey were higher for the octopus when foraging with fishy partners.

The details revealed by this study suggest this relationship is far more sophisticated than other cross-species hunting associations examined to date.

Despite the huge evolutionary gap between these animals (the equivalent of about 550 million years), both fish and octopus show clear signs of social competence and advanced cognition.

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

Biologist Thayana Giao holds a Green Sea turtle during an intentional capture to monitor turtles’ health, weight and pollution level, by Universidade Federal Fluminense (UFF), in the Guanabara Bay in Rio de Janeiro, Brazil August 29, 2024.
| Photo Credit: Reuters

Sea turtles in the Guanabara Bay of Rio de Janeiro are getting healthier after struggling for years with a tumour disease that hampers their movement, sight and feeding, and ultimately leads to their death.

Scientists said it came after authorities made an effort to clean up the water of the natural harbor that shapes the identity of the region.

Research has linked fibropapillomatosis, a benign tumour in sea turtles, to both a virus and environmental factors.

Kassia Coelho, a professor of veterinary pathological anatomy at the Federal Fluminense University, said samples taken from the animals and the water pointed to a much healthier environment.

“It’s about analysing health by collecting blood and tumours from these turtles, and also biometrics of the animals, seeing their growth over the years and monitoring these animals from one year to the next,” she said.

“Many of these turtles are recaptured and we can assess whether they’ve grown, whether they’re heavier, whether they’ve lost weight, whether they have more tumours or fewer tumours.”

Surrounded by a dense urban population, Guanabara Bay was once a nursery for marine life but has over the years suffered from sewage and other garbage being dumped there.

In 2022, scientists found that three quarters of sea turtles there were carrying the tumours.

While research is still ongoing, Gustavo Baila, an oceanographer and professor at the Federal University of Rio Grande, said sea turtles have been healthier since 2023.

“These are very important species for marine conservation,” he said. “We had observed a high incidence of sea turtles with tumours, with deformities that ended up being very serious for the development of these animals.”

Brazil is home to five of the seven species of sea turtles that exist worldwide. However, their natural habitat is sometimes severely impacted by humans. Conservationists have called for stricter measures to protect these animals.

Alexandre Bianchini, a vice president at Brazilian water and sewage treatment company Aegea, said some 2 billion reais ($356.42 million) had been invested into cleaning up the water in the area. “Now, nature responds,” he said.