These footprints, found nearly a half-century ago, may be almost four times older than first thought, scientists now report.
Finding and eating bugs when other food was scarce helped primates — including our ancestors — evolve bigger and better brains. At least that’s the conclusion of a new study in Costa Rica.
Old mice show improved memory when blood from young mice circulated through their brains, a new study finds. Other studies suggest one ingredient in that young blood might be all it takes to deliver benefits.
Doctors and scientists are exploring ways to stem the growing global crisis of antibacterial resistance.
Doctors and scientists are not the only people who can help preserve the effectiveness of life-saving antibiotics. Even patients have a role to play, as these tips show.
ScienceBefore reading 1. With a partner, research the difference between bacteria and viruses.2. Think of the last time you were ill with something other than a cold. What symptoms did you have? What kind of medicines were you given?During reading1. How do microbes become resistant to antibiotics?2. What is the leading cause of death among young adults, worldwide?3. Some disease experts once thought that tuberculosis could be wiped out by 2025. Why is that now unlikely?4. Why might a doctor prescribe an antibiotic for a patient that won’t be helped by it?5. What did Daniella Meeker have doctors do that resulted in them reducing the number of antibiotics they prescribed?6. What are hospitalists?7. How can researchers find out what kind of antibiotics a TB germ might be resistant to?
Immediate and aggressive drug treatment of a baby born with HIV appeared to have cured the girl. In fact, a follow-up shows, she still has the disease.
What may have been the bird world’s biggest flier ever had wings so long, they would have had trouble flapping fast enough to keep it aloft in tough winds. But this behemoth would have been able to soar both far and fast.
Producing food can put a lot of climate-warming pollutants into the atmosphere. But some foods, especially meats, contribute more than others.
Have antibiotics become too popular? Overusing these medicines fuels resistant germs that pose a global health threat.
A mold proved the source of the first known antibiotic: penicillin. But chemical dyes would lead to the first antibiotics used in treating people.
SCIENCEBefore reading1. What might cause people to get sick?2. When you have been sick, what kinds of medicines have you been given? Have you ever been given an antibiotic? (Some antibiotics include penicillin, amoxicillin and erythromycin.)During reading1. What is antibiotic resistance? Why are people worried about it?2. How can antibiotic-resistant germs travel from people out into the environment?3. Why is MRSA particularly nasty in hospitals and prisons?4. Why shouldn’t a person infected with a virus be treated with an antibiotic?5. What class of infectious germs causes most types of common cough?6. Why do farmers give antibiotics to healthy animals?7. Why would Kellogg Schwab call antibiotic use in healthy farm animals “a direct threat to human health”?8. What is a plasmid?
A day on the beach might deliver more than a tan (or sunburn). It may also release potent brain chemicals that leave people with a pleasurable feeling.
This late-Jurassic dino was also a bird. Its ample coat of feathers emerged before any need for flight.
Fossils found in a Spanish cave have features that are a combination of Neandertals and other species. The mix suggests Neandertal roots go back even farther than scientists had suspected.
NASA released details of the new, more flexible apparel being designed for long-distance travelers — such as those bound for another planet.
Using lasers, scientists measured the temperature of water droplets that remained liquid even when super-cold.
Studying blue whales, spinner dolphins and other cetaceans demands clever ways to unveil the out-of-sight behaviors of these marine denizens.
Can a dolphin be a whale — or a whale be a dolphin? Yes, because the terms used to describe the biggest marine mammals are quite elastic and fuzzy.
SCIENCEBefore reading1. Explain what you know about marine mammals. How many species can you name?2. What threats do whales face? List as many as you can.During reading1. How much can a humpback whale weigh?2. What are cetaceans?3. Why is sound more useful than light in exploring the ocean?4. What happens to the pulses of sound that Kelly Benoit-Bird sends into the water? What can those pulses reveal?5. How did the spinner dolphin get its name?6. Describe how spinner dolphins hunt fish.7. About how long is an adult blue whale?8. Explain the similarities between a tree’s rings and a whale’s earwax.