Jacob A Tennessen, Harvard University

The fight against infectious disease is a race against evolution. Bacteria become resistant to antibiotics. Viruses adapt to spread more quickly. Diseases transmitted by insects present another evolutionary front: Insects themselves can evolve resistance to the poisons that people use to kill them.

In particular, the mosquito-borne disease malaria kills over 600,000 people annually. Since World War II, people have battled malaria with insecticides – chemical weapons intended to kill Anopheles mosquitoes infected with the Plasmodium parasites that cause the disease.

However, mosquitoes are quickly evolving counterstrategies that make these insecticides ineffective, putting millions of people at greater risk of deadly infection. My colleagues and I have newly published research showing how.

Insecticide resistance threatens public health

As an evolutionary geneticist, I study natural selection – the basis for adaptive evolution. Genetic variants that best promote survival can replace less advantageous versions, causing species to change. Anopheles mosquitoes are frustratingly adept at evolving.

In the mid-1990s, most African Anopheles were susceptible to pyrethroids, a popular type of insecticide originally derived from chrysanthemums. Anopheles control relies on two pyrethroid-based methods: insecticide-treated bed nets to protect sleepers, and indoor residual spraying of insecticide against the walls of homes. These two methods alone likely prevented over a half-billion cases of malaria between 2000 and 2015.

However, mosquitoes today from Ghana to Malawi are often able to survive insecticide concentrations 10 times the previously lethal dose. Along with Anopheles control efforts, agriculture also inadvertently exposes mosquitoes to pyrethroids and contributes to insecticide resistance.

In some African locales, Anopheles is already showing resistance to all four main classes of insecticide used for malaria control.

Adaptation in Latin American mosquitoes

Anopheles mosquitoes and the malaria-causing Plasmodium also occur outside Africa, where insecticide resistance is less well-researched.

In much of South America, the main malaria vector is Anopheles darlingi. This mosquito species has diverged evolutionarily from the African vectors so extensively that it might be a different genus, Nyssorhynchus. Along with colleagues from eight countries, I analyzed over 1,000 Anopheles darlingi genomes to understand its genetic diversity, including any recent changes due to human activity. My collaborators collected these mosquitoes at 16 locations ranging from the Atlantic coast of Brazil to the Pacific side of the Andes in Colombia.

We found that, like its African counterparts, Anopheles darlingi shows extremely high genetic diversity – more than 20 times that of humans – indicating that very large populations of this insect exist. A species with such a vast gene pool is well poised to adapt to new challenges. The right mutation giving it the advantage it needs is more likely to pop up when there are so many individuals. And once that mutation starts to spread, it’s protected by numbers since it won’t be wiped out if a few mosquitoes die by chance.

In contrast, bald eagles in the contiguous U.S. were never able to evolve resistance against the insecticide DDT and approached extinction. Evolution is more efficient among millions of insects than mere thousands of birds. And indeed, we saw signals of adaptive evolution in the resistance-related genes of Anopheles darlingi occurring over the past few decades.

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Mosquitoes evolve to detoxify poisons

Insecticides like pyrethroids and DDT share the same molecular target: channels in nerve cells that can open and close. When open, the nerve cell stimulates other cells. These insecticides force the channels to remain open and continuously fire, causing paralysis and death. However, insects can evolve resistance by changing the shape of the channel itself.

Earlier genetic scans performed by other researchers had not detected this type of resistance in Anopheles darlingi, and neither did ours. Instead, we found that resistance is evolving in another way: a group of genes encoding enzymes that break down toxic compounds. High activity of these enzymes, called P450, frequently underlies resistance to insecticides in other mosquitoes. The same cluster of P450 genes has changed independently at least seven times across South America since insecticide use began in the mid-20th century.

In French Guiana, a different set of P450 genes exhibits a similar evolutionary pattern, cementing the clear connection between these enzymes and adaptation. Moreover, when we exposed mosquitoes to pyrethroids in sealed bottles, differences among the P450 genes of individual mosquitoes were linked to the length of time they stayed alive.

Insecticide-heavy campaigns against malaria have been only sporadic in South America and may not be the main driver behind this evolution. Instead, it’s possible that mosquitoes are being exposed indirectly to agricultural insecticides. Intriguingly, we saw the strongest signs of evolution in places where farming is prevalent.

Toward more sophisticated vector control

Despite new vaccines and other recent advances against malaria, mosquito control remains essential for reducing disease.

Some countries are launching trials of gene drives to control malaria, which involve forcing a genetic modification into a mosquito population to reduce their numbers or their tolerance for Plasmodium. Such prospects are exciting, though the relentless adaptability of mosquitoes could be an obstacle.

I and others are revising methods to efficiently test for emerging insecticide resistance. Genome-scale sequencing remains important to detect new or unexpected evolutionary responses. The risk of adaptation is highest under a continuous, strong selection pressure, so minimizing, switching and staggering pesticides can help thwart resistance.

Success in the fight against evolving resistance will require a coordinated effort of monitoring, and reacting accordingly. Unlike evolution, humans can think ahead.

Jacob A Tennessen, Research Scientist in Immunology and Infectious Diseases, Harvard University

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

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Last Updated on April 11, 2026 by Daily News Staff

April 10, 2026 — NASA’s Artemis II crew has safely returned to Earth, marking the successful completion of the first crewed mission to the Moon’s vicinity in more than 50 years.

The Orion spacecraft splashed down in the Pacific Ocean off the coast of California at 5:07 p.m. PDT, carrying NASA astronauts Reid Wiseman, Victor Glover, Christina Koch, and Canadian astronaut Jeremy Hansen back home after a nearly 10-day journey through deep space.

🚀 A Mission for the Record Books

During the mission, the crew traveled a total of 694,481 miles, reaching a maximum distance of 252,756 miles from Earth—farther than any humans have ever gone, surpassing the Apollo 13 record set in 1970.

Launched on April 1 aboard NASA’s powerful Space Launch System (SLS) rocket, Artemis II tested critical systems needed for future missions, including life support, navigation, and deep space communication.

🌕 Science, Exploration, and Stunning Views

While orbiting the Moon, the astronauts captured more than 7,000 images, including views of the lunar far side, a rare solar eclipse, and detailed observations of craters, lava flows, and surface features.

The mission also included scientific experiments to better understand how the human body responds to deep space conditions, helping prepare for longer missions to the Moon and Mars.

🛰️ Safe Return and Recovery

Following splashdown, recovery teams quickly reached the spacecraft and transported the crew by helicopter to the USS John P. Murtha for initial medical evaluations. The astronauts are expected to return to NASA’s Johnson Space Center for further assessments.

🌍 What Comes Next

With Artemis II complete, NASA is now turning its focus to Artemis III, the next mission aimed at landing astronauts on the Moon and establishing a long-term human presence.

The success of Artemis II marks a major step forward in humanity’s return to deep space—and the beginning of a new era of exploration.

For more information on NASA’s Artemis program, visit the official NASA website.

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🔗 Source & Further Reading

• NASA Blog: Artemis II Flight Day 10 – Re-entry Live Updates
• NASA Artemis II Mission Overview
• NASA Artemis Program – Return to the Moon
• Orion Spacecraft Details and Technology
• NASA Image and Video Library (Artemis II Photos & Media)

Dive into “The Knowledge,” where curiosity meets clarity. This playlist, in collaboration with STMDailyNews.com, is designed for viewers who value historical accuracy and insightful learning. Our short videos, ranging from 30 seconds to a minute and a half, make complex subjects easy to grasp in no time. Covering everything from historical events to contemporary processes and entertainment, “The Knowledge” bridges the past with the present. In a world where information is abundant yet often misused, our series aims to guide you through the noise, preserving vital knowledge and truths that shape our lives today. Perfect for curious minds eager to discover the ‘why’ and ‘how’ of everything around us. Subscribe and join in as we explore the facts that matter.  https://stmdailynews.com/the-knowledge/

Last Updated on April 10, 2026 by Daily News Staff

Emily A. Margolis, Smithsonian Institution

While I was leading a tour of the National Air and Space Museum in January 2026, a visitor posed this insightful question: “Why has it taken so long to return to the Moon?”

After all, NASA had the know-how and technology to send humans to the lunar surface more than 50 years ago as part of the Apollo program. And, as another tour guest reminded us, computers today can do so much more than they could back then, as evidenced by the smartphones most of us carry in our pockets. Shouldn’t it be easier to get to the Moon than ever before?

The truth is that sending humans into space safely continues to be difficult, especially as missions increase in complexity.

New technologies require years of study, development and testing before they can be certified for flight. And even then, systems and materials can behave in ways that surprise and worry engineers and mission planners; look no further than Boeing’s Starliner CFT mission or the performance of the Orion heat shield on Artemis I.

Issues with Starliner’s thrusters led NASA to return the spacecraft from the International Space Station without its crew. Unanticipated chipping of the Orion heat shield resulted in years of research, culminating in NASA altering the atmospheric reentry plans for the Artemis II mission.

NASA’s programs also require sustained political will and financial support across multiple presidential administrations, Congresses and fiscal years. As a historian of human spaceflight, I have studied the space agency’s efforts to engage the broader public to convince American taxpayers that their programs hold value for the nation.

NASA is now on the eve of the first crewed flight to the Moon since the Apollo era: Artemis II. A crew of four will conduct a lunar flyby, laying the groundwork, the agency hopes, for a landing on the Artemis IV mission.

The story of NASA’s effort to return humans to the Moon is long and winding, demonstrating the complexities of turning grand ambitions into real missions.

Post-Apollo

In early 1970, with two successful Moon landings on the books, President Richard Nixon sought to reduce NASA’s budget to better align with his administration’s priorities. This decision put the space agency in a difficult position, which ultimately led to the cancellation of three planned Apollo missions to conserve funding for its plans for long-term human activity in low Earth orbit.

NASA repurposed the third stage of a Saturn V rocket to create the first U.S. space station, Skylab, which operated from 1973 to 1974. The space agency used leftover Saturn IB rockets and Apollo command and service modules to send crews to the station.

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Over the next three decades, NASA developed and operated the space shuttle. The fleet of space shuttle orbiters supported satellite deployment and microgravity research on orbital missions of up to 17 days. This work was meant to enable future long-duration human missions and provide benefits to people on Earth. For example, data from protein crystal growth experiments have informed the development of medicines.

The space shuttle program facilitated the construction, maintenance and staffing of a continuously inhabited research platform in orbit, the International Space Station. The first modules launched in late 1998.

Where to next?

As the new millennium approached, the Clinton administration tasked NASA to think beyond the space station. What could robots and humans do next in space? And where could they do it? Notably, the White House expressed an interest in locations beyond low Earth orbit.

NASA, it turned out, was well positioned to meet the administration’s request. NASA Administrator Daniel Goldin was already thinking about preparing proposals for the next presidential administration and had recently sponsored a human lunar return study. In 1999, he established a team to investigate new technologies, missions and destinations for the 21st century.

This work took on new significance following the tragic loss of the space shuttle Columbia crew in February 2003. Many people, including those in the new George W. Bush White House, wondered whether the human spaceflight program should continue – and, if so, how.

Administration discussions culminated in Bush’s Vision for Space Exploration in 2004, which directed NASA to retire the space shuttle after the completion of the space station. It called for returning humans to the Moon on a crew exploration vehicle designed for destinations beyond low Earth orbit.

It also called for continuing robotic exploration of Mars and engaging companies and international partners in space. Fifteen years earlier, President George H. W. Bush had also announced a Moon and Mars exploration program, but congressional concerns about cost kept space travelers close to home.

The Constellation program’s legacy

In December 2004, NASA began the process of finding a manufacturer for the crew exploration vehicle. By August 2006, the space agency awarded Lockheed Martin the contract to build the capsule, which it had named Orion – the same Orion planned to carry Artemis astronauts to the Moon.

Years of research, development and testing followed for Orion as well as the Ares I crew and Ares V cargo launch vehicles. Together, these technologies made up the Constellation program.

Constellation had two primary objectives: in the near term, to help transport crew to and from the space station after the space shuttle program ended; in the long term, to enable human lunar exploration.

Building systems that could work in both Earth orbit and around the Moon was supposed to save the time and cost of developing two vehicles. Similarly, adapting space shuttle program hardware could supposedly cut costs.

During the first months of Barack Obama’s presidency in 2009, the administration initiated an independent review of NASA’s human spaceflight plans. The Augustine Committee, chaired by retired aerospace executive Norman Augustine, found that the agency’s ambitions outstripped its limited budget, leading to significant delays. The first Orion spacecraft was likely to arrive after the space station ceased operations.

The committee proposed several paths forward at the current funding level, which prioritized space shuttle and space station programs. An additional annual investment of US$3 billion would allow for human exploration beyond low Earth orbit.

Ultimately, the Obama administration canceled Constellation, but two of its technologies lived on, thanks to U.S. senators from states that would have been affected by cuts.

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The NASA Authorization Act of 2010 funded Orion’s continued development, shifting responsibility for space station crew transportation to commercial vehicles. It also directed NASA to develop the space launch system, a redesigned Ares V heavy booster, to send Orion to the Moon. The technical strategy had political benefits, too, preserving jobs in numerous congressional districts by providing continuity for aerospace contractors.

In December 2014, a Delta IV heavy rocket launched the first Orion capsule on a test flight, providing engineers with data on spacecraft systems and the heat shield. By October 2015, the space launch system had completed a critical design review, the last step before manufacturing could begin.

Introducing Artemis

In December 2017, the new Trump administration issued a policy directive shifting the focus of NASA’s human spaceflight program back to the Moon. The space agency would use Orion and the space launch system in a race to meet an ambitious 2024 landing date. NASA officially named the program Artemis in May 2019.

The 25-day Artemis I mission, launched in November 2022, was a major milestone for the program. This uncrewed flight was the first flight of the space launch system and the first to integrate SLS and Orion. It laid the groundwork for Artemis II, which will be the first crewed flight of the SLS.

Over more than 50 years, each new presidential administration has reassessed the place of spaceflight among its priorities, either encouraging or curtailing NASA’s efforts to return humans to the lunar surface.

Each crewed flight requires the alignment of technical expertise, political will and financial support over years if not decades. For the space fans who plan to watch the Artemis II launch, the wait for countdown may feel long. But it’s just a blink in NASA’s long journey back to the Moon.

Emily A. Margolis, Curator of Contemporary Spaceflight, National Air and Space Museum, Smithsonian Institution

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

Dive into “The Knowledge,” where curiosity meets clarity. This playlist, in collaboration with STMDailyNews.com, is designed for viewers who value historical accuracy and insightful learning. Our short videos, ranging from 30 seconds to a minute and a half, make complex subjects easy to grasp in no time. Covering everything from historical events to contemporary processes and entertainment, “The Knowledge” bridges the past with the present. In a world where information is abundant yet often misused, our series aims to guide you through the noise, preserving vital knowledge and truths that shape our lives today. Perfect for curious minds eager to discover the ‘why’ and ‘how’ of everything around us. Subscribe and join in as we explore the facts that matter.  https://stmdailynews.com/the-knowledge/

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