Experiment shows dogs are able to remember toy names for up to two years

Credit: Pixabay/CC0 Public Domain

A trio of ethologists at Eötvös Loránd University, in Hungary, has found, via experimentation, that some dogs are able to remember toy names for up to two years. In their study, published in the journal Biology Letters, Shany Dror, Ádám Miklósi and Claudia Fugazza taught toy names to several dogs and then hid the toys away for two years to learn more about the dogs' long-term memory.

Prior research has shown that dogs are capable of associating human words with a toy—when asked to retrieve "Squeaker," for example, a dog would ignore other toys in a group and fetch the one requested. Prior research has also shown that some breeds are better at making these associations, as are some individuals within breeds—such dogs are known as gifted word learner dogs.

The researchers involved in this new study wondered if such dogs retain these associations due to repeated use, or if they, like humans, are able to store associations in long-term memory. To find out, they designed and carried out an experiment involving five dogs that had previously been trained to associate human words with toys and to fetch them upon request.

Each of the dogs was taught to associate names with 12 toys they had never seen before. After making sure that the dogs had learned the names thoroughly, the researchers stored all the toys for two years. They then brought the dogs out individually, showed each one the toys and then, after mixing the test toys with others that were familiar to the dogs in another room, asked them to retrieve the test toys by calling out the associated name. Each dog was tested twice for each toy.

The researchers found that overall, the dogs were accurate in retrieving the toy specified 44% of the time, while some had an accuracy rate of up to 60%. The researchers note that the results are far better than chance, proving that the dogs had remembered the toys and the names for two years—a clear indication that they had stored them in long-term memory.

More information: Shany Dror et al, Dogs with a vocabulary of object labels retain them for at least 2 years, Biology Letters (2024). DOI: 10.1098/rsbl.2024.0208

Journal information: Biology Letters 

© 2024 Science X Network

Dogs prefer food over toys, according to study

2 dogs rescued nearly a week after deadly landslide in Alaska

Sep 4, 2024

James and Bill Montiver lost nearly everything after a massive landslide in Ketchikan, Alaska, demolished their home. Six days later, firefighters found their two dogs in the debris. David Muir shares the story of the rescue and reunion.

Animal rights groups urge Norway to probe death of 'spy' whale, saying it was shot


Regina Haug, founder of OneWhale, is seen in a photo provided to media by her organization showing the body of Hvaldimir, a celebrated beluga they allege was shot to death. Photo courtesy of OneWhale/Release

Sept. 4 (UPI) -- Two prominent animal rights organizations are calling on Norwegian authorities to launch a criminal investigation into the recent death of a celebrated beluga whale, which they say was fatally shot.

The body of the whale named Hvaldimir was recovered Saturday by Noway-based non-profit Marine Mind from waters off the coast of the Scandinavian country after it had been spotted floating on the ocean by local.

Hvaldimir -- a portmanteau on the Norwegian word "hval," or whale in English, and the first name of the Russian leader, Vladimir Putin -- is believed to have been trained as a spy by the Kremlin.

On Wednesday, OneWhale and NOAH filed a police report with the Southwestern Police District and the Norwegian National Authority urging the launch of an investigation into the whale's death and for it to be prosecuted as an economic and environmental crime.
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OneWhale is a non-profit organization that was dedicated to protect Hvaldimir and NOAH is Norways largest animal rights organization. In a joint statement, they say they have "compelling evidence" showing Hvaldimir's cause of death was intentional human-inflicted injury.

"Although the official autopsy report is still pending, preliminary findings indicate that the whale was killed by gunshot wounds," the organizations said, adding that several veterinarians, biologists, and ballistics experts have reviewed their photographic evidence, which includes close-up shots of the whale's injuries and they "strongly suggest" its death was criminal.

"The injuries on the whale are alarming and of a nature that cannot rule out a criminal act -- it is shocking. Given the suspicion of a criminal act, it is crucial that the police are involved quickly," Siri Martinsen, veterinarian and leader of NOAH, said.

Regina Haug, founder of OneWhale and who has known Hvaldimir for the past five years, said she saw the corpse and a bullet lodged inside.

"There is no question that this kind, gentle animal was senselessly murdered," Haug said.

"We will pursue justice for Hvaldimir and hope that someone comes forward with information about his killing."

Graphic photos disseminated by the organizations show the corpse of the whale with at least one small and bloody whole, a puncture that suggests a gunshot wound.

UPI has contacted local police for comment.

The results of an official autopsy are pending and Marine Mind, the organization that found Hvaldimir, is calling for calm and to refrain from speculating on the cause of death.

"The Veterinary Institute has not yet released the results from its investigations," it said in a statement on Facebook.

"When we found Hvaldimir on Saturday, it was not possible to immediately determine the cause of death, and therefore it is important to refrain from speculation until the institute has completed its work. Until then, we hope people stick to the established facts."

Marine Mind said it is directly assisting where it can to determine the cause of Hvaldimir's death, but until one can be established "temporary assumptions will not be useful for anything other than publicity."

Hvaldimir was first spotted five years ago in Norwegian waters, and its friendly nature and potential use as a spy for Russia had grabbed headlines and the attention of animal conservationists.

Volvo gives up plan to sell only EVs by 2030

João da Silva
Business reporter

Getty Images
The car maker blamed changing market conditions for its decision to give up a target it had announced only three years ago


Car company Volvo has announced it has abandoned its target to produce only fully electric cars by 2030, saying it now expects it will also be selling some hybrid vehicles by that date.

The car maker blamed changing market conditions for its decision to give up a target it had announced only three years ago.

It comes as the industry faces a slowdown in demand in some major markets for electric vehicles (EVs) and uncertainty due to the imposition of trade tariffs on EVs made in China.

Volvo, which has traditionally flaunted its environmental credentials, joins other major car makers General Motors and Ford, which have also rowed back on their EV ambitions.

Volvo now expects at least 90% of its output to be made up of both electric cars and plug-in hybrids by 2030.

The Swedish company may also sell a small number of so-called mild hybrids, which are more conventional vehicles with limited electrical assistance.

"We are resolute in our belief that our future is electric," said Jim Rowan, chief executive of Volvo, in a statement.

"However, it is clear that the transition to electrification will not be linear, and customers and markets are moving at different speeds."

The company also said the business climate for EVs had changed, due to factors such as a slow rollout of charging infrastructure and the withdrawal of consumer incentives.

Volvo is majority-owned by Chinese car giant Geely and because it uses factories in China, it will also be affected by tariffs on imports of Chinese-made EVs in Europe and North America.

Palestinian girl killed in West Bank was looking out the window, her father says

Members of the Israeli military operate in what they say is the Jenin Area, in the Israeli-occupied West Bank, in this handout image released on Aug 31, 2024.
PHOTO: Israeli Army Handout via Reuters file

PUBLISHED ON September 04, 2024 

JENIN, West Bank — A 16-year-old Palestinian girl who was killed in the occupied West Bank city of Jenin this week was shot dead by an Israeli sniper as she looked out of the window of her home, her father said on Sept 4.

The Israeli military has said it is looking into reports of the death of Lujain Osama Musleh on Sept 3, during a major operation in different areas of the West Bank involving hundreds of soldiers and armoured vehicles.

Osama Musleh said troops had surrounded the house next door to his when his daughter was shot through the forehead after opening the curtain to look outside.


"She didn't go to the roof, she didn't hurl a stone, and she wasn't carrying a weapon," he said.

"She is 16 years old. The only thing she did is look from the window and the soldier saw her and shot her. One bullet that targeted her forehead."

More than 30 Palestinians have been killed and dozens of arrests have been made during the operation, which began a week ago in different areas of the West Bank. Most have been claimed as members of armed Palestinian groups like Hamas, Islamic Jihad or Fatah but some, like Lujain, have been uninvolved civilians.

The Israeli military said it launched the operation, its biggest in the West Bank for months, to thwart Iranian-backed militant groups preparing attacks on Israeli civilians.

Over the past week, troops have fought gunbattles with Palestinian fighters, damaging houses and other buildings and tearing up large stretches of roadway in what it says is a hunt for improvised explosive devices.

Food, water shortages

Kamal Abu al-Rub, the governor of Jenin, said Israeli troops had made 12 major incursions into Jenin since the start of the Gaza war almost a year ago. "This is the most severe, the most painful and oppressive," he told Reuters.

He said the operation, now in its eighth day, was causing major hardship to people in the city and the adjacent refugee camp, a densely populated area housing thousands of people whose families left their homes or were driven out during the 1948 Middle East war.

Privately organised aid trucks from other areas of the West Bank had helped alleviate some shortages of food and water and products such as baby formula but "arbitrary" controls were impeding deliveries in many areas.

"The situation of people in the besieged areas in particular is very difficult," he said.

About 4,000-5,000 people had been ordered from their homes in the refugee area and the eastern part of Jenin city and were being put up in temporary accommodation arranged by the Palestinian Authority, he said.


In Tulkarm, another flashpoint city in the West Bank, the military said soldiers killed two armed fighters during an exchange of fire, finding an M-16 automatic rifle beside the men. In addition, soldiers located an explosive device in a baby stroller as well as an explosives laboratory.

Thousands of Palestinians have been arrested in raids and more than 680 — fighters and civilians — have been killed in the West Bank and East Jerusalem since the war in Gaza began nearly 11 months ago, according to Palestinian health ministry figures.

At the same time, dozens of Israelis have been killed in attacks by Palestinians.

Vietnamese activist begins 50-day hunger strike

The political prisoner is protesting an unfair appeal and the political rise of To Lam.

By RFA Vietnamese
2024.09.04

Vietnamese teacher and independent journalist Le Trong Hung and his wife Do Le Na are shown in an undated photo.

 Facebook: Tu Dinh Huong

Read RFA coverage of this topic in Vietnamese

Le Trong Hung, who is serving a five-year prison sentence for “propaganda against the state” in Vietnam’s Nghe An province, began a 50-day hunger strike Wednesday.

The teacher and independent journalist wants the chance to appeal his conviction and is protesting against the promotion of former police chief To Lam, first to president, and then to general secretary of the Communist Party, Vietnam’s top job.

But Hung’s wife told Radio Free Asia she is concerned that only drinking water will have serious implications for his health.

Hung, 45, was arrested on March 27, 2021 after announcing plans to stand as a candidate for the National Assembly, or parliament, that year.

Later that year, he was sentenced to five years in prison and five years of probation.

During a family visit on July 16, Hung started to tell his wife Do Le Na about his planned hunger strike, saying it was “related to the National Assembly and To Lam … protesting him sitting in the wrong place,” before prison guards stopped him.

Then Minister of Public Security To Lam and the clip of him eating a gold-plated steak. (Tik Tok: @nusr_et/RFA edit)

To Lam was elected minister of public security in 2016. He became state president in May this year and general secretary on Aug. 3, following the death of Nguyen Phu Trong.

As police chief, he was widely criticized for talking about the need to stamp out corruption and then dining out on a US$1,900 gold-encrusted steak at a celebrity chef’s restaurant during an official trip to London. One Vietnamese activist, who mocked Lam’s lavish dinner on YouTube, was jailed for five-and-a-half years.

Prison officers warned Hung not to mention the hunger strike when he made his monthly phone call home on Aug 16. But when they weren’t paying attention, he spoke to his wife about it.

“My husband plans to go on a hunger strike, drinking only water for 50 days, but I am trying to convince him to reduce it to 30 days because October 4th this year is our 15th wedding anniversary,” Na told RFA Vietnamese on Wednesday. “However, Hung has not agreed yet.” 

She said Hung could be punished by losing privileges such as family visits and the phone calls home.

However, Na said a hunger strike was "almost the only way at this time for him to express his determination to follow the purpose and path he has chosen."

RFA Vietnamese tried to phone Nghe An’s Prison No.6 to ask about Hung’s case but the number wouldn't connect.

---

RELATED STORIES

Three Vietnamese activists given human rights awards

Vietnamese journalist serving 5-year sentence loses appeal

Vietnamese find top cop's pricey London steak hard to stomach

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Last year, Hung went on a 30-day hunger strike, also starting on Sept. 4. He said he wanted to persuade authorities to give him the chance to appeal his conviction again because he was denied a lawyer at his initial appeal and his family wasn’t told when it was taking place.

He also asked prison officers to respect prisoners' rights and requested a visit from a National Assembly representative, saying he wanted to propose the establishment of a constitutional court in Vietnam. None of his requests was met.

Hung is a former teacher at Xa Dan school for the deaf in Hanoi.

He is well-known in Vietnam after live streaming news reports on Facebook and the CHTV pro-democracy YouTube channel, criticizing government policies and denouncing corruption.

Translated by RFA Vietnamese. Edited by Mike Firn.

Agriculture accelerated human genome evolution to capture energy from starchy foods

New study finds rapid increase over last 12,000 years in genes for enzymes that digest starch

Date: September 4, 2024

Source: University of California - Berkeley

Summary:

Scientists have suspected that modern humans have more genes to digest starch than our hunter-gatherer ancestors, but the amylase locus of the genome is hard to study. Researchers have now developed new methods to isolate the multiple amylase genes and compare the locus to ancient genomes. They found that amylase gene number has increased from an average of eight to more than 11 over the past 12,000 years.


FULL STORY

Over the past 12,000 years, humans in Europe have dramatically increased their ability to digest carbohydrates, expanding the number of genes they have for enzymes that break down starch from an average of eight to more than 11, according to a new study by researchers from the U.S., Italy and United Kingdom.


The rise in the number of genes that code for these enzymes tracks the spread of agriculture across Europe from the Middle East, and with it, an increasingly starchy human diet rich in high-carbohydrate staples such as wheat and other grains. Having more copies of a gene usually translates to higher levels of the protein the genes code for -- in this case, the enzyme amylase, which is produced in saliva and the pancreas to break down starch into sugar to fuel the body.

The study, published today (Sept. 4) in the journal Nature, also provides a new method for identifying the causes of diseases that involve genes with multiple copies in the human genome, such as the genes for amylase.

The research was led by Peter Sudmant, assistant professor of integrative biology at the University of California, Berkeley, and Erik Garrison of the University of Tennessee Health Science Center in Memphis.

"If you take a piece of dry pasta and put it in your mouth, eventually it'll get a little bit sweet," Sudmant said. "That's your salivary amylase enzyme breaking the starches down into sugars. That happens in all humans, as well as in other primates."

Chimpanzee, bonobo and Neanderthal genomes all have a single copy of the gene on chromosome 1 that codes for the salivary amylase, referred to as AMY1. The same is true for the two pancreatic amylase genes, AMY2A and AMY2B. These three genes are located close to one another in a region of the primate genome known as the amylase locus.

Human genomes, however, harbor vastly different numbers of each amylase gene.

"Our study found that each copy of the human genome harbors one to 11 copies of AMY1, zero to three copies of AMY2A, and one to four copies of AMY2B," said UC Berkeley postdoctoral fellow Runyang Nicolas Lou, one of five first authors of the paper. "Copy number is correlated with gene expression and protein level and thus the ability to digest starch."

The researchers discovered that, while around 12,000 years ago humans across Europe had an average of about four copies of the salivary amylase gene, that number has increased to about seven. The combined number of copies of the two pancreatic amylase genes also increased by half a gene (0.5) on average over this time in Europe.

Survival advantage of multiple amylase genes

Overall, the incidence of chromosomes with multiple copies of amylase genes (that is, more total copies than chimpanzees and Neanderthals) increased sevenfold over the last 12,000 years, suggesting that this provided a survival advantage for our ancestors.

The researchers also found evidence for an increase in amylase genes in other agricultural populations around the world, and that the region of the chromosomes where these amylase genes are located looks similar in all these populations, no matter what specific starchy plant that culture domesticated. The findings demonstrate that as agriculture arose independently around the world, it seems to have rapidly altered the human genome in nearly identical ways in different populations to deal with increased carbohydrates in the diet.

In fact, the researchers found that the rate of evolution leading to changes in amylase gene copy number was 10,000 times faster than that of single DNA base pair changes in the human genome.

"It has long been hypothesized that the copy number of amylase genes had increased in Europeans since the dawn of agriculture, but we had never been able to sequence this locus fully before. It is extremely repetitive and complex," Sudmant said. "Now, we're finally able to fully capture these structurally complex regions, and with that, investigate the history of selection of the region, the timing of evolution and the diversity across worldwide populations. Now, we can start thinking about associations with human disease."

One suspected association is with tooth decay. Previous studies have suggested that having more copies of AMY1 is associated with more cavities, perhaps because the saliva does a better job of converting starch in chewed food into sugar, which feeds bacteria that eat away at teeth.

The research also provides a method for exploring other areas of the genome -- those involving the immune system, skin pigmentation and the production of mucus, for example -- that have undergone rapid gene duplication in recent human history, Garrison said.

"One of the exciting things we were able to do here is probe both modern and ancient genomes to dissect the history of structural evolution at this locus," he said.

These methods can also be applied to other species. Previous studies have shown that animals that hang out around humans -- dogs, pigs, rats and mice -- have more copies of the amylase gene than their wilder relatives, apparently to take advantage of the food we throw away.

"This is really the frontier, in my opinion," Garrison said. "We can, for the first time, look at all of these regions that we could never look at before, and not just in humans -- other species, too. Human disease studies have really struggled in identifying associations at complex loci, like amylase. Because the mutation rate is so high, traditional association methods can fail. We're really excited how far we can push our new methods to identify new genetic causes of disease."

From hunter-gatherer to agrarian

Scientists have long suspected that humans' ability to digest starch may have increased after our ancestors transitioned from a hunter-gatherer lifestyle to a settled, agricultural lifestyle. This shift was shown to be associated with more copies of the amylase genes in people from societies that domesticated plants.

But the area of the human genome where these copies reside has been difficult to study because traditional sequencing -- so-called short-read sequencing techniques that cut the genome into chunks of about 100 base pairs, sequence the millions of pieces and then reassemble them into a genome -- was unable to distinguish gene copies from one another. Complicating matters, some copies are inverted, that is, they are flipped and read from the opposite strand of DNA.

Long-read sequencing allows scientists to resolve this region, reading DNA sequences thousands of base pairs long to accurately capture repetitive stretches. At the time of the study, the Human Pangenome Reference Consortium (HPRC) had collected long-read sequences of 94 human haploid genomes, which Sudmant and colleagues used to assess the variety of contemporary amylase regions, called haplotypes. The team then assessed the same region in 519 ancient European genomes. The HPRC data helped avoid a common bias in comparative genomic studies, which have used a single, averaged human genome as a reference. The genomes from the HPRC, referred to as a pangenome, provide a more inclusive reference that more accurately captures human diversity.

Joana Rocha, a UC Berkeley postdoctoral fellow and co-first author of the paper, compared the region where amylase genes cluster to what she called "sculptures made of different Lego bricks. Those are the haplotype structures. Previous work had to take down the sculpture first and infer from a pile of bricks what the sculpture may have looked like. Long-read sequencing and pangenomic methods now allow us to directly examine the sculpture and thus offer us unprecedented power to study the evolutionary history and selective impact of different haplotype structures."

Using specially developed mathematical modeling, the researchers identified 28 different haplotype structures among the 94 long-read genomes and thousands of realigned short-read human genomes, all of which cluster into 11 groups, each with a unique combination of AMY1, AMY2A and AMY2B copy numbers.

"These remarkably complex, crazy structures -- regions of gene duplication, inversion and deletion in the human genome -- have evolved independently in different human populations over and over again, even before the rise of agriculture," Sudmant said.

Analysis of the many contemporary human genomes also pointed to an origin 280,000 years ago of an initial duplication event that added two copies of AMY1 to the human genome.

"That particular structure, which is predisposed to high mutation rates, emerged 280,000 years ago, setting the stage for later on, when we developed agriculture, for people who had more copies to have increased fitness, and then for these copy numbers to be selected for," Sudmant said. "Using our methods, for the first time we could really date the initial duplication event."

Alma Halgren, a UC Berkeley graduate student in bioengineering, and Davide Bolognini and Alessandro Raveane of Human Technopole in Milan, Italy, are also first authors of the paper. Other co-authors are Andrea Guarracino of UTHSC, Nicole Soranzo of Human Technopole and the University of Cambridge in the United Kingdom, and Jason Chin of the Foundation for Biological Data Science in Belmont, California. Sudmant's research is funded by the Institute of General Medical Sciences of the U.S. National Institutes of Health (R35GM142916).

Story Source:

Materials provided by University of California - Berkeley. Original written by Robert Sanders. Note: Content may be edited for style and length.


Journal Reference:Davide Bolognini, Alma Halgren, Runyang Nicolas Lou, Alessandro Raveane, Joana L. Rocha, Andrea Guarracino, Nicole Soranzo, Chen-Shan Chin, Erik Garrison, Peter H. Sudmant. Recurrent evolution and selection shape structural diversity at the amylase locus. Nature, 2024; DOI: 10.1038/s41586-024-07911-1


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University of California - Berkeley. "Agriculture accelerated human genome evolution to capture energy from starchy foods." ScienceDaily. ScienceDaily, 4 September 2024. <www.sciencedaily.com/releases/2024/09/240904141503.htm>.

Scientists uncover hidden source of snow melt: Dark brown carbon

Date: September 4, 2024

Source: Washington University in St. Louis  

Summary :Researchers have quantified the effect of dark brown carbon on snow melt.

FULL STORY

Wildfires leave potent climate heaters behind in their wake, particles that enhance the absorption of sunlight and warm the atmosphere. Dropped on snow like a wool poncho, these aerosols darken and decrease the surface reflectance of snowy places.

But it was not yet understood just how different types of smoke particles contribute to these effects.

In a study recently published in npj Climate and Atmospheric Science, researchers at Washington University in St. Louis model how dark-brown carbon (d-BrC) -- light absorbing, water insoluble organic carbon -- from wildfires plays a much larger role as a snow-warming agent than previously recorded.

It's 1.6 times as potent a warmer compared to what researchers previously thought was the main culprit, black carbon.

In the Tibetan Plateau and other midlatitude regions, deposition of water insoluble organic carbon on snow have been previously recorded, "But nobody really looked under the hood to investigate their snow melting potential," said Rajan Chakrabarty, a professor at WashU's McKelvey School of Engineering.

Chakrabarty's PhD student, Ganesh Chelluboyina, a McDonnell International Scholars Academy fellow, and Taveen Kapoor, a postdoctoral fellow, have spent the bulk of their time at WashU taking up that challenge.

The team likens d-BrC to an "evil cousin" of black carbon, and much like black carbon, wildfires deposit it upon snow caps like switching out a white t-shirt for dark brown poncho.

These particles can't be washed away or bleached to the point of losing their absorptivity.

And when the snow loses its reflectivity and warms up, this increases surrounding air temperatures and further notches up the warming cycle.

Without accounting for d-BrC, researchers have likely been underestimating the snow melt from wildfire smoke deposition, and this research will ensure more accurate climate models and measurements.

As massive wildfires become more ubiquitous, policymakers will have to figure out how to mitigate this form of carbon to reduce anomalous snow melt.

Though d-BrC absorbs slightly less light than black carbon, it makes up for it in quantity, being four times more abundant in wildfire plumes compared to BC.

The team plans to further document the real-world effects of d-BrC at work as they enter the experimental phase of research.

How do you do snow-aerosol experiments without going to the field?

In this case, they get a four-foot-tall snow globe for the lab.

"We'll be dropping atomized water droplets into the top of the chamber, creating snow, then deposit aerosols on it," Chelluboyina said.

Story Source:

Materials provided by Washington University in St. Louis. Original written by Leah Shaffer. Note: Content may be edited for style and length.


Journal Reference:Ganesh S. Chelluboyina, Taveen S. Kapoor, Rajan K. Chakrabarty. Dark brown carbon from wildfires: a potent snow radiative forcing agent? npj Climate and Atmospheric Science, 2024; 7 (1) DOI: 10.1038/s41612-024-00738-7


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Washington University in St. Louis. "Scientists uncover hidden source of snow melt: Dark brown carbon." ScienceDaily. ScienceDaily, 4 September 2024. <www.sciencedaily.com/releases/2024/09/240904141501.htm>.

FLORIDA
Aggressive seagrass species discovered in Biscayne Bay

By JoAnn Adkins
September 4, 2024

An invasive species of seagrass has been on a steady march across the world, taking over ecosystems well beyond its native waters of the Red Sea, Persian Gulf and Indian Ocean. Scientists have long wondered when it would reach the waters off the coast of Florida. FIU scientists say that day has arrived.

FIU marine scientist Justin Campbell has positively identified Halophila stipulacea growing in Crandon Marina and nearby areas of Biscayne Bay. It is the first time this non-native species has been found in waters along the continental United States.

“I think this species could pose a considerable threat,” Campbell said. “There are several reports of it being able to outcompete native seagrasses in other areas across the Caribbean. It is plausible that this could also be true for seagrasses here in South Florida.”

A marina worker first noticed the seagrass last month and reached out to Campbell who conducted tests to determine the species. Halophila stipulacea first started spreading its distribution with the opening of the Suez Canal in the late 1800s, hitching rides on the anchors and other parts of boats. By the early 2000s, it was found in the Caribbean.

Healthy seagrass meadows are vital for healthy oceans. They are nursery habitats for commercially and economically important fish as well as shrimp, stone crabs, scallops and other crustaceans and shellfish. Seagrasses are a primary food source for sea turtles, manatees and other marine herbivores. And for the health of the planet, seagrasses are really good at sucking carbon emissions out of the air and storing that carbon long-term. While scientists are still working to understand possible impacts from the invasive species entering waters around the U.S., early research suggests some fish species may avoid the shorter seagrass when scouting nursery locations and local sea turtles in the Caribbean avoid eating the invasive seagrass, preferring native species as part of their regular diets.

While most species of seagrass are on the decline from warming waters and other human-induced impacts, Halophila stipulacea has the unique ability to grow quickly and adapt to different conditions including salinity levels, temperature and light availability. Just a small piece can float through water and grow. Once it settles into soil, it can take hold easily and grow at a variety of depths. While most seagrass species require shallower depths to attain sunlight, Halophila stipulacea has been observed flourishing at depths of 60 feet or more.

“The arrival of yet another invasive species to Florida is a reminder that all of our earth is interconnected and that human actions have the power to change the planet, for good or bad,” said James Fourqurean, co-author of the research and director of the Coastlines and Oceans Division in FIU’s Institute of Environment. Fourqurean has studied seagrasses, especially those in Florida, for more than 40 years. A foremost expert, he is one of the lead scientists in the International Blue Carbon Working Group, as well as scientific representative to the International Blue Carbon Policy Working Group — both dedicated to the recognition and preservation of seagrass meadows, mangroves and tidal salt marshes as critical contributors to slowing the rise of CO2 in the atmosphere.

“Given the importance of seagrasses to a healthy South Florida, we now need to do what we can to limit the spread of this invasive species and be wary of disruptions to the natural order it may cause,” Fourqurean said.

Stipulacea has a very different appearance and structure than the native seagrasses in South Florida and throughout the Caribbean. At least 19 Caribbean islands have reported this seagrass growing in nearby waters and, in some cases, overtaking meadows of native grass.

“We don’t know whether Stipulacea provides similar ecological benefits as compared to our native species,” Campbell said. “Our seagrass meadows here are some of the most pristine and well-protected in the Western Hemisphere. They are iconic and emblematic. We certainly don't want to lose them.”

So how long has this non-native species been in South Florida? It is hard for Campbell to say, but based on the current distribution, he believes it first started taking root several years ago. It had gone unnoticed because, to the casual observer, it can be difficult to distinguish from native vegetation, he said.

Crandon Marina can accommodate medium and large sized sailboats, likely capable of travel to and from areas where Stipulacea is well-established. This is one possible and likely way the non-native seagrass reached Biscayne Bay. With other large marinas in the region, Campbell said surveys and monitoring should be expanded now that this invasive species is confirmed to be in South Florida.

Air pollution linked to decrease in IVF birth rate success

Thursday, 05 September, 2024




Exposure to fine particulate matter (PM) prior to the retrieval of oocytes (eggs) during in vitro fertilisation (IVF) can reduce the odds of achieving a live birth by almost 40%, according to a new study presented at the ESHRE 40th Annual Meeting and published in the journal Human Reproduction.

Conducted over an eight-year period in Perth, Western Australia, the research analysed 3659 frozen embryo transfers from 1836 patients. The median female age was 34.5 years at the time of oocyte retrieval and 36.1 years at the time of frozen embryo transfer. The study examined air pollutant concentrations over four exposure periods prior to oocyte retrieval (24 hours, two weeks, four weeks and three months), with models created to account for co-exposures.

“This is the first study that has used frozen embryo transfer cycles to separately analyse the effects of pollutant exposure during the development of eggs and around the time of embryo transfer and early pregnancy,” said lead author Dr Sebastian Leathersich, from the King Edward Memorial Hospital for Women. “We could therefore evaluate whether pollution was having an effect on the eggs themselves, or on the early stages of pregnancy.”

Analysing PM10 exposure in the two weeks leading up to oocyte collection, the researchers found that the odds of a live birth decreased by 38% when comparing the highest quartile of exposure (18.63 to 35.42 µg/m3) to the lowest quartile (7.08 to 12.92 µg/m3). Increasing PM2.5 exposure in the three months prior to oocyte retrieval was also associated with decreased odds of live birth, falling from 0.90 in the second quartile to 0.66 in the fourth quartile.

Importantly, the negative impact of air pollution was observed despite excellent overall air quality during the study period, with PM10 and PM2.5 levels exceeding WHO guidelines on just 0.4% and 4.5% of the study days, respectively.

“Our results reveal a negative linear association between particulate matter exposure during the two weeks and three months prior to oocyte collection and subsequent live birth rates from those oocytes,” Leathersich said. “This association is independent of the air quality at the time of frozen embryo transfer. These findings suggest that pollution negatively affects the quality of the eggs — not just the early stages of pregnancy, which is a distinction that has not been previously reported.”

Exposure to fine particulate matter through outdoor air pollution is already associated with a range of adverse health conditions, including cardiovascular and respiratory diseases. In 2021, 97% of the urban EU population was exposed to concentrations of PM2.5 above the WHO annual guideline of 5 µg/m3. But although epidemiological data show a clear correlation between pollution and poorer reproductive outcomes, the exact mechanisms remain unclear

“Climate change and pollution remain the greatest threats to human health, and human reproduction is not immune to this,” Leathersich said. “Even in a part of the world with exceptional air quality, where very few days exceed the internationally accepted upper limits for pollution, there is a strong negative correlation between the amount of air pollution and the live birth rate in frozen embryo transfer cycles. Minimising pollutant exposure must be a key public health priority.”