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New study of inbreeding among endangered right whales reveals encouraging finding

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HALIFAX – The tiny population of critically endangered North Atlantic right whales has long had to deal with inbreeding. But a new scientific study, led by researchers at Saint Mary’s University in Halifax, is reporting an encouraging finding.

Even though inbreeding appears to be limiting the number of calves born each year, it’s not having an impact on genetic diversity — a trait that is key to the survival of any species.

“The fact that they’re retaining that genetic diversity is a really good sign for their future,” said Carla Crossman, a PhD candidate in the university’s biology department. “We’re not losing genetic diversity as fast as we might otherwise. (But) we don’t know why.”

Last October, the North Atlantic Right Whale Consortium estimated there were 356 North Atlantic right whales left on the planet.

The new peer-reviewed study, published Wednesday in the journal Royal Society Open Science, says researchers initially found that most female North Atlantic right whales were not giving birth to calves every three years, as females in the much larger southern population typically do.

“The interval is much higher across the (northern) population,” Crossman said, adding that some mature females in the North Atlantic have never given birth.

The research team, which included scientists from other parts of Canada and from the United States, determined through genome sequencing that each female’s level of inbreeding had nothing to do with their ability to give birth.

“There wasn’t a clear relationship between how inbred a female was and her reproductive success,” Crossman said. “But what we did find is that all of the individuals in the population had more genetic diversity than would be expected, given (the size of) the population.”

The team reported another key finding based on past research on known mother-calf pairs and known mother-father-calf triads: highly inbred calves weren’t showing up in the population. The researchers believe inbred fetuses are dying in the womb.

“We think there’s an increased rate of fetal loss due to inbreeding,” Crossman said. “This does explain some of the poor reproductive success that we’re seeing …. Whatever the mechanism, it is maintaining genetic diversity in the population because all of the calves are more genetically diverse than expected.”

The “mechanism” has probably enabled the whales to avoid harmful mutations caused by inbreeding, she said. “That means they can persist a bit better at a small population size.”

The team’s findings could be used to “recalibrate” the expectations of those in charge of managing the North Atlantic right whale population, she said.

Despite the good news about genetics, Crossman said none of these findings will mean much unless there’s a substantial decrease in the number of whales killed by ship strikes and entanglements with fishing gear, which are the leading causes of death for this species.

Last fall, the North Atlantic Right Whale Consortium — a group of scientists, industry members and government officials who study the whales — said the latest data showed the number of human-caused injuries was on the rise.

As of 2022, deaths were not outpacing births — a good sign — but conservationists remain worried the species is still slipping closer to extinction because many of these injuries will lead to deaths, while other injured whales may not be able to reproduce.

So far this season, five entangled North Atlantic right whales have been spotted in Canadian waters, including an adult male known as Dropcloth, spotted Saturday off the northeastern coast of New Brunswick near Miscou Island.

This report by The Canadian Press was first published Aug. 1, 2024.

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STD epidemic slows as new syphilis and gonorrhea cases fall in US

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NEW YORK (AP) — The U.S. syphilis epidemic slowed dramatically last year, gonorrhea cases fell and chlamydia cases remained below prepandemic levels, according to federal data released Tuesday.

The numbers represented some good news about sexually transmitted diseases, which experienced some alarming increases in past years due to declining condom use, inadequate sex education, and reduced testing and treatment when the COVID-19 pandemic hit.

Last year, cases of the most infectious stages of syphilis fell 10% from the year before — the first substantial decline in more than two decades. Gonorrhea cases dropped 7%, marking a second straight year of decline and bringing the number below what it was in 2019.

“I’m encouraged, and it’s been a long time since I felt that way” about the nation’s epidemic of sexually transmitted infections, said the CDC’s Dr. Jonathan Mermin. “Something is working.”

More than 2.4 million cases of syphilis, gonorrhea and chlamydia were diagnosed and reported last year — 1.6 million cases of chlamydia, 600,000 of gonorrhea, and more than 209,000 of syphilis.

Syphilis is a particular concern. For centuries, it was a common but feared infection that could deform the body and end in death. New cases plummeted in the U.S. starting in the 1940s when infection-fighting antibiotics became widely available, and they trended down for a half century after that. By 2002, however, cases began rising again, with men who have sex with other men being disproportionately affected.

The new report found cases of syphilis in their early, most infectious stages dropped 13% among gay and bisexual men. It was the first such drop since the agency began reporting data for that group in the mid-2000s.

However, there was a 12% increase in the rate of cases of unknown- or later-stage syphilis — a reflection of people infected years ago.

Cases of syphilis in newborns, passed on from infected mothers, also rose. There were nearly 4,000 cases, including 279 stillbirths and infant deaths.

“This means pregnant women are not being tested often enough,” said Dr. Jeffrey Klausner, a professor of medicine at the University of Southern California.

What caused some of the STD trends to improve? Several experts say one contributor is the growing use of an antibiotic as a “morning-after pill.” Studies have shown that taking doxycycline within 72 hours of unprotected sex cuts the risk of developing syphilis, gonorrhea and chlamydia.

In June, the CDC started recommending doxycycline as a morning-after pill, specifically for gay and bisexual men and transgender women who recently had an STD diagnosis. But health departments and organizations in some cities had been giving the pills to people for a couple years.

Some experts believe that the 2022 mpox outbreak — which mainly hit gay and bisexual men — may have had a lingering effect on sexual behavior in 2023, or at least on people’s willingness to get tested when strange sores appeared.

Another factor may have been an increase in the number of health workers testing people for infections, doing contact tracing and connecting people to treatment. Congress gave $1.2 billion to expand the workforce over five years, including $600 million to states, cities and territories that get STD prevention funding from CDC.

Last year had the “most activity with that funding throughout the U.S.,” said David Harvey, executive director of the National Coalition of STD Directors.

However, Congress ended the funds early as a part of last year’s debt ceiling deal, cutting off $400 million. Some people already have lost their jobs, said a spokeswoman for Harvey’s organization.

Still, Harvey said he had reasons for optimism, including the growing use of doxycycline and a push for at-home STD test kits.

Also, there are reasons to think the next presidential administration could get behind STD prevention. In 2019, then-President Donald Trump announced a campaign to “eliminate” the U.S. HIV epidemic by 2030. (Federal health officials later clarified that the actual goal was a huge reduction in new infections — fewer than 3,000 a year.)

There were nearly 32,000 new HIV infections in 2022, the CDC estimates. But a boost in public health funding for HIV could also also help bring down other sexually transmitted infections, experts said.

“When the government puts in resources, puts in money, we see declines in STDs,” Klausner said.

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The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Science and Educational Media Group. The AP is solely responsible for all content.

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World’s largest active volcano Mauna Loa showed telltale warning signs before erupting in 2022

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WASHINGTON (AP) — Scientists can’t know precisely when a volcano is about to erupt, but they can sometimes pick up telltale signs.

That happened two years ago with the world’s largest active volcano. About two months before Mauna Loa spewed rivers of glowing orange molten lava, geologists detected small earthquakes nearby and other signs, and they warned residents on Hawaii‘s Big Island.

Now a study of the volcano’s lava confirms their timeline for when the molten rock below was on the move.

“Volcanoes are tricky because we don’t get to watch directly what’s happening inside – we have to look for other signs,” said Erik Klemetti Gonzalez, a volcano expert at Denison University, who was not involved in the study.

Upswelling ground and increased earthquake activity near the volcano resulted from magma rising from lower levels of Earth’s crust to fill chambers beneath the volcano, said Kendra Lynn, a research geologist at the Hawaiian Volcano Observatory and co-author of a new study in Nature Communications.

When pressure was high enough, the magma broke through brittle surface rock and became lava – and the eruption began in late November 2022. Later, researchers collected samples of volcanic rock for analysis.

The chemical makeup of certain crystals within the lava indicated that around 70 days before the eruption, large quantities of molten rock had moved from around 1.9 miles (3 kilometers) to 3 miles (5 kilometers) under the summit to a mile (2 kilometers) or less beneath, the study found. This matched the timeline the geologists had observed with other signs.

The last time Mauna Loa erupted was in 1984. Most of the U.S. volcanoes that scientists consider to be active are found in Hawaii, Alaska and the West Coast.

Worldwide, around 585 volcanoes are considered active.

Scientists can’t predict eruptions, but they can make a “forecast,” said Ben Andrews, who heads the global volcano program at the Smithsonian Institution and who was not involved in the study.

Andrews compared volcano forecasts to weather forecasts – informed “probabilities” that an event will occur. And better data about the past behavior of specific volcanos can help researchers finetune forecasts of future activity, experts say.

(asterisk)We can look for similar patterns in the future and expect that there’s a higher probability of conditions for an eruption happening,” said Klemetti Gonzalez.

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The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Science and Educational Media Group. The AP is solely responsible for all content.

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Waymo’s robotaxis now open to anyone who wants a driverless ride in Los Angeles

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Waymo on Tuesday opened its robotaxi service to anyone who wants a ride around Los Angeles, marking another milestone in the evolution of self-driving car technology since the company began as a secret project at Google 15 years ago.

The expansion comes eight months after Waymo began offering rides in Los Angeles to a limited group of passengers chosen from a waiting list that had ballooned to more than 300,000 people. Now, anyone with the Waymo One smartphone app will be able to request a ride around an 80-square-mile (129-square-kilometer) territory spanning the second largest U.S. city.

After Waymo received approval from California regulators to charge for rides 15 months ago, the company initially chose to launch its operations in San Francisco before offering a limited service in Los Angeles.

Before deciding to compete against conventional ride-hailing pioneers Uber and Lyft in California, Waymo unleashed its robotaxis in Phoenix in 2020 and has been steadily extending the reach of its service in that Arizona city ever since.

Driverless rides are proving to be more than just a novelty. Waymo says it now transports more than 50,000 weekly passengers in its robotaxis, a volume of business numbers that helped the company recently raise $5.6 billion from its corporate parent Alphabet and a list of other investors that included venture capital firm Andreesen Horowitz and financial management firm T. Rowe Price.

“Our service has matured quickly and our riders are embracing the many benefits of fully autonomous driving,” Waymo co-CEO Tekedra Mawakana said in a blog post.

Despite its inroads, Waymo is still believed to be losing money. Although Alphabet doesn’t disclose Waymo’s financial results, the robotaxi is a major part of an “Other Bets” division that had suffered an operating loss of $3.3 billion through the first nine months of this year, down from a setback of $4.2 billion at the same time last year.

But Waymo has come a long way since Google began working on self-driving cars in 2009 as part of project “Chauffeur.” Since its 2016 spinoff from Google, Waymo has established itself as the clear leader in a robotaxi industry that’s getting more congested.

Electric auto pioneer Tesla is aiming to launch a rival “Cybercab” service by 2026, although its CEO Elon Musk said he hopes the company can get the required regulatory clearances to operate in Texas and California by next year.

Tesla’s projected timeline for competing against Waymo has been met with skepticism because Musk has made unfulfilled promises about the company’s self-driving car technology for nearly a decade.

Meanwhile, Waymo’s robotaxis have driven more than 20 million fully autonomous miles and provided more than 2 million rides to passengers without encountering a serious accident that resulted in its operations being sidelined.

That safety record is a stark contrast to one of its early rivals, Cruise, a robotaxi service owned by General Motors. Cruise’s California license was suspended last year after one of its driverless cars in San Francisco dragged a jaywalking pedestrian who had been struck by a different car driven by a human.

Cruise is now trying to rebound by joining forces with Uber to make some of its services available next year in U.S. cities that still haven’t been announced. But Waymo also has forged a similar alliance with Uber to dispatch its robotaxi in Atlanta and Austin, Texas next year.

Another robotaxi service, Amazon’s Zoox, is hoping to begin offering driverless rides to the general public in Las Vegas at some point next year before also launching in San Francisco.

The Canadian Press. All rights reserved.

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