How Did the Iguana Cross the Pacific? Mystery Solved
The iguanas in Fiji and Tonga have always been an evolutionary puzzle. Iguanas are native to the Americas and the Caribbean, but somehow millions of years ago, a small group of them made it all the way to Fiji. There was never land bridge between the two distant places. So how on Earth did they get there?
Evolutionary biologist Simon Scarpetta of the University of San Francisco and his colleagues think they have solved the mystery. They believe the reptiles caught a lift across the ocean on a platform of trees, plants, or debris. These rafts occasionally break off from coastlines and drift out to sea as floating islands. Animals on them may wind up in new and unexpected destinations. In the case of the Fijian iguanas, researchers believe they made a record-breaking trip by drifting over 8,000km across the Pacific Ocean.
'You could imagine some kind of cyclone knocking over trees where there were a bunch of iguanas and maybe their eggs, and then they caught the ocean currents and rafted over," Scarpetta told The New York Times.
It is quite rare for vertebrates to survive such trips. But iguanas can go weeks without food or fresh water, making them well-suited for long voyages of deprivation. They have been seen rafting before, but their journeys have never been this long. In 1995, a group of about 15 iguanas were spotted hitching a ride 320km between Caribbean islands aboard hurricane debris. The team thinks their slow metabolism and rainwater allowed them to survive the incredibly long journey to Fiji.
There have long been two hypotheses about these out-of-place reptiles. First, that they rafted over from the Americas; and second, that a now-extinct ancestor drifted over from Asia or Australia.
Scarpetta and his team studied the evolutionary history of over 200 species of iguanas and lizards. The four species in Fiji are most closely related to the desert iguanas of Mexico and the American Southwest. That is clearly where they came from, although the timing of their great voyage remains uncertain.
"This suggests that as soon as land appeared where Fiji now resides, these iguanas may have colonized it," Scarpetta said. "Regardless of the actual timing of dispersal, the event itself was spectacular."
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Newsweek
15 hours ago
- Newsweek
NASA To Build Nuclear Reactor on the Moon: What To Know
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The federal employee buyout program implemented by President Donald Trump's administration has led to 750 employees voluntarily resigning, and about 1,000 probationary employees were terminated when the policy first began in February. The layoffs have raised concerns about the agency's ability to maintain critical projects. Reports of the planned lunar nuclear reactor also raises questions about the timing of NASA's Artemis II moon mission, which has been delayed repeatedly. What To Know According to Politico, Duffy said in the documents that the accelerated timeline was prompted by fears that China and Russia would be able to get a reactor on the moon by the mid-2030s and effectively gatekeep lunar activity. Under the accelerated timeline, the nuclear reactor would be ready to launch in late 2029 and would be required to generate a minimum 100 kilowatts of electrical power, The New York Times reported. 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What Happens Next It remains to be seen whether Duffy or NASA will comment on the reports or announce a timeline for building a nuclear reactor on the moon.
Boston Globe
21-07-2025
- Boston Globe
Hundreds of NASA employees, past and present, sign letter of formal dissent
In an email statement, Bethany Stevens, the NASA press secretary, said NASA would never compromise on safety. 'Any reductions — including our current voluntary reduction — will be designed to protect safety-critical roles,' she said. Advertisement 'To ensure NASA delivers for the American people, we are continually evaluating mission lifecycles, not on sustaining outdated or lower-priority missions,' Stevens said. Get Starting Point A guide through the most important stories of the morning, delivered Monday through Friday. Enter Email Sign Up Upheaval within NASA continued Monday, when Makenzie Lystrup, director of NASA's Goddard Space Flight Center in Greenbelt, Md., announced she was 'stepping aside' on Aug. 1. In an email sent to center employees at 12:45 p.m. and shared with The New York Times, she did not give a reason for her departure. Cynthia Simmons, the center's deputy director, will take over as acting director. 'I am honored to have been part of this incredible journey with you,' Lystrup wrote. The NASA letter follows similar letters of criticism by federal employees at the National Institutes of Health and the Environmental Protection Agency. Dr. Jay Bhattacharya, the NIH director, said he welcomed respectful dissent, but the EPA placed 144 employees who signed that agency's letter on leave. Advertisement 'We're scared of retaliation,' said Monica Gorman, an operations research analyst at Goddard. She said that staff members 'go to the bathroom to talk to each other, and look under the stalls to make sure that no one else is there before we talk.' Gorman is one of 287 current and former NASA employees who signed the letter, although more than half did so anonymously. More than 15,000 people work at the space agency. Prominent scientists outside of NASA, including 20 Nobel Prize winners, also offered their names in support. 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It was part of changes instituted at NASA after the losses of the Columbia and Challenger space shuttles when concerns of some engineers were brushed aside. Advertisement Stand Up for Science, a nonprofit organization that has organized opposition to the Trump administration's cutbacks of science research, has helped coordinate the letters to the three agencies. In its budget request to Congress in June, the Trump administration proposed slashing NASA's budget by almost 25 percent. NASA's science mission directorate, which includes earth science, solar system missions and astrophysics, would face a cut of 47 percent, to $3.9 billion from $7.3 billion. Nineteen currently operating science missions, including the Chandra X-ray Observatory, the Juno mission at Jupiter and the two Orbiting Carbon Observatories, would be turned off and discarded. 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Yahoo
09-07-2025
- Yahoo
Here's why you should catch some rays this summer
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