It's Spawning Season: Are Horseshoe Crabs Down For the Count?

Migratory birds and humans have long relied on the odd creatures; biomedical companies even harvest their blue blood to create a clotting agent. But scientists fear they're on the decline and are now working on ways to set harvest limits.

Walk along Mid-Atlantic beaches right now and you may see odd creatures that look like they belong in the dinosaur age. They're horseshoe crabs, and scientists worry their numbers are declining.

To gather more information about what's happening to the crabs, volunteers are dispatched along the coast each year at this time for an annual count.

It's getting dark, and these sea creatures are lined up for miles on Kitts Hummock Beach near Dover, Del., where they come ashore to spawn.

Horseshoe crabs are sometimes called living fossils because they've been around for millions of years and survived when other species didn't. The females are larger than males, some as big as a dinner plate. The shell has a horseshoe shape and from a few steps back they look like shallow green Army helmets.

Horseshoe crabs spawning on Kitts Hummock Beach near Dover, Del. Most of the year they live out in the ocean but in late spring and early summer they migrate toward shore where females bury eggs in the sand and males fertilize them. Typically there are many more males than females. The males gather around the females and those closest to the females are more likely to fertilize the eggs.

Drexel Siok, environmental scientist at Delaware National Estuarine Research Reserve, holds a horseshoe crab that's been tagged on Kitts Hummock Beach near Dover, Del. During the annual count volunteers make a note if they find a tagged crab. Researchers then use the information to learn where crabs are moving over time.

Faith Hewes learned about horseshoe crabs from her father, Jim Hewes, a seventh-grade science teacher. He volunteers with Delaware National Estuarine Research Reserve to lead counting teams.

"You can tell when they're old," Faith says. "Because they have a lot of stuff on their backs and a lot of barnacles."

As the high tide recedes, Hewes instructs a half-dozen volunteers. They hold meter-wide white squares made of plastic pipe.

"When you put in your square, go right to the water's edge, OK? Drop it in," Hewes says.

Then he reminds them, "You're counting the crabs that are only within the square itself."

Two teams do this 50 times each along a mile of beach. Hewes says if a crab walks out of the square, count that one too.

"All right, guys, let's have fun and let's count crabs," he says.

With rubber boots and headlamps, the volunteers dig through the many males to find the few females laying eggs in the sand.

Volunteer Tom Huber and his daughter Melanie bend down and dig in while his son Benson stands with a clipboard.

"They count them. I just write it down," Benson says. "If they have tags I have to record those as well."

Some crabs are tagged so researchers can track where they go.

Tom Huber, a volunteer counter, uses a one meter square of plastic pipe to mark the boundary of where they are reporting. They lay down the square 50 times along a mile of beach to get a sample of how many are there. If a crab comes into the boundary or leaves it while the pipe is down it can be counted.

There are plenty of crabs tonight, but overall there's still concern.

The fishing industry uses horseshoe crabs for bait. Migratory birds eat their eggs. And biomedical companies use their blue blood to make a special clotting agent.

Kirby Rootes-Murdy with the Atlantic States Marine Fisheries Commission says here in the Delaware Bay region numbers are stable. And south of here the population is increasing.

"What we are seeing, in terms of concerning evidence, is a decrease in abundance for the New York and, kind of, New England regions," he says.

And Rootes-Murdy points out another important thing about horseshoe crabs: It turns out they aren't really crabs.

"It's pretty nuts that they have the name horseshoe crab but they're much more closely related to spiders and scorpions than they are to actual blue crabs that people are familiar with," he says.

Back at the shore, Maggie Pletta with the estuarine reserve says don't let that spider-scorpion thing worry you.

"They can't sting you; they're not venomous. They're not using their tail as a spear," Pletta says. "So if you see them on the beach and they're stuck upside down, flip 'em over. Return them the favor — just flip 'em — and let them get back to doing their business."

Volunteers will be out here on the beach at night through June 18 this year counting the horseshoe crabs. npr

locust vs grasshopper

In a 2010 article on locusts that was published in the Encyclopedia of Animal Behavior, Alexandre Vsevolo Latchininsky, Extension Entomologist for the State of Wyoming, explains that "all locusts are grasshoppers but not all grasshoppers are locusts." He defines locusts as "short-horned grasshoppers (Orthoptera: Acrididae), distinguished by their density-dependent behavioral, physiological, and phenotypic polymorphism."

The phenotype mutability refers to the fact that for some subspecies of locusts, the different stages of life are marked by different colors and even body shapes. However, it is the behavioral aspect—the mass grouping together—that is most notable. The act of swarming, or exhibiting a so-called "gregarious phase," is the most obvious characteristic that identifies a subspecies of grasshopper as a locust.

Latchininsky explains in his paper that "out of more than 12,000 described grasshopper species in the world, only about a dozen exhibit pronounced behavioral and/or morphological differences between phases of both nymphs and adults, and should be considered locusts." And in fact, the tendency to swarm together is a relatively recent phenomenon in grasshopper evolution.

It's Raining Nitrogen In A Colorado Park. Farmers Can Help Make It Stop

It's May in Rocky Mountain National Park, but on a mountainside 10,829 feet above sea level, snow is falling. It's pelting Jim Cheatham, a biologist with the National Park Service. Shrugging off the cold, Cheatham seizes a teachable moment. This snow, he says, holds more than just water.

"Chances are it's carrying the excess nitrogen we're talking about," says Cheatham.

For the past eight years, the biologist has spent most of his time thinking about how nitrogen pollution is changing the park's forests, wildflowers and alpine lakes. He's also been looking for a way to stop it.

As Cheatham explains, it's not that nitrogen is bad in and of itself. It's that there's too much of it in the park. Think about putting fertilizer, which is basically nitrogen, on your lawn or garden, he said.

"What if you applied that fertilizer — and that's exactly what it is — at that rate — 15 times what's on the label," he says. "Weird things are going to happen."

Weird things are happening in the park's alpine meadows and in the lakes nestled beneath its craggy peaks. Cheatgrass, an invasive weed, is making its way higher and higher into the park, buoyed by extra fertilizer, as are other weeds. Native trees are weakened by the extra nitrogen. Rivers are becoming more acidic.

Cheatham recalled a moment one day when he was driving through the park with his family, in what should have been a relatively pristine alpine environment.

"And I happened to catch what I thought was Canada thistle, you know catch sight of that while driving," said Cheatham. "I stopped, and I panicked."

Those spiky, purple flowers are a highly invasive weed. That thistle isn't supposed to be there. When it is, that means it is crowding out native plants, like wildflowers.

And it gets weirder.

"This past year, for the first time we saw an algal bloom in one of our high mountain lakes," said Cheatham. "Never been seen before, never been documented before."

Scientists are still investigating the links between the algae bloom and nitrogen, said Cheatham. Regardless of if the link is direct, they are sure of one thing: Too much nitrogen is throwing off the park's ecological balance. If nitrogen levels stay high, the park could look completely different in just a few decades.

After he saw that invasive thistle, Cheatham called out what he called a "SWAT team" of biologists who attacked and removed the weed. A better solution, though, would be to stop the extra nitrogen from getting to the park in the first place.

That's where Jon Slutsky comes in. He's a dairy farmer in Wellington, Colo., about 50 miles east of Rocky Mountain National Park.

Slutsky admits that at first it's hard to make a connection between a dairy farm on Colorado's Eastern Plains and biological weirding in Rocky Mountain National Park.

Yet strange as it might seem, farmers on the plains are responsible for a significant amount of the extra nitrogen that's falling in the park, as rain, or snow.

Other sources include automobiles, oil and gas operations, and other industrial activities from within Colorado. Some nitrogen comes from as far away as California, Nevada, Nebraska and Iowa, according to a 2009 report. Spurred by a 2004 petition from Trout Unlimited and the Environmental Defense Fund, the Park Service, the U.S. Environmental Protection Agency and the Colorado Department of Public Health and Environment began to focus on reducing nitrogen in the park.

Pointing at a corral where a few of his 1,500 dairy cows were chowing down, Slutsky says this is where the problem starts.

"Ammonia is created out in the corrals — the cows are designed so perfectly, they provide everything — so the urine hits the ground and it creates ammonia," Slutsky says.

Ammonia, which contains nitrogen, can come from a cow urine and manure reacting with the air. Ammonia is a gas, and it can be transformed into another type of particle, ammonium nitrate, that is small and easily carried on the wind.

Normally, wind comes from the west. So most of the nitrogen created at dairies like Slutsky's, and other farms, is carried to places like Nebraska. A few times a year, though, the winds change.

"Not real often. But on occasion they do. Maybe a dozen times a year," says Slutsky.

When that happens, the nitrogen gets carried up into the park. If it rains or snows, it falls on the park, providing fertilizer for weeds like Canada thistle and stressing out the park's ecosystem.

Neither Cheatham nor cattle feedlot owners want this to happen. That's why the Park Service and other federal agencies are partnering with groups of Front Range farmers to use a novel alert system.

Slutsky and around 50 other farmers signed up for a voluntary program where they get an alert when the winds are blowing the wrong way, from the east, and a system is likely to move in and rain nitrogen down on the park.

The alert tells them how long the weather system will last, often two days or less. In response, the farmers can implement conservation practices that keep nitrogen out of the air. Slutsky might decide to move manure another day. Another farmer might postpone a fertilizer application.

Texas A&M University professor Brock Faulkner is a consultant for the project, which went through a trial run in 2014, sending out 10 warnings to Eastern Plains farmers.

"If we could shift the timing of those practices so that those emissions occur at a time when they're less likely to cause detrimental environmental impacts, that would be fantastic," says Faulkner.

Participants ironed out the kinks and showed that the alert system functioned. Faulkner said during the trial run, at least 60 percent of the farmers notified were willing to change their practices to avoid releasing more nitrogen.

While nitrogen levels haven't started declining in the park, Cheatham says they have stopped increasing.

Farmers hope it works. As Slutsky says, they're doing it because they want to, but also to avoid future regulations: "We all either have either the hammer over or our conscience or both."

It's not just Rocky Mountain National Park that could benefit.

If this type of voluntary program works, it could be a model for other places where pollution from agriculture has caused problems, like the Gulf of Mexico or Lake Erie. npr

bruce is now caitlyn jenner

The revelation was made in Vanity Fair, which tweeted an image of Jenner on the cover of its July issue.

"If I was lying on my deathbed and I had kept this secret and never ever did anything about it, I would be lying there saying, 'You just blew your entire life,' " Jenner tellsthe magazine's Buzz Bissinger.

Jenner, 65, described to ABC's Diane Sawyer in April a lifelong struggle with gender identity.

As NPR's Christopher Dean Hopkins reported at the time: "Jenner told Sawyer that he hoped that being public with his identity and struggle might help change perceptions and increase acceptance of transgender individuals."

As ABC's Sawyer noted at that time, the prime-time interview was Jenner's last as Bruce, but Jenner was still most comfortable with male pronouns. That appears to have now changed — as Vanity Fair referred to Jenner using the female pronouns "she" and "her." And, the magazine notes, Jenner says: "I don't really get hung up" about it.

Here's more from Vanity Fair:

"Jenner tells Bissinger about how she suffered a panic attack the day after undergoing 10-hour facial-feminization surgery on March 15 — a procedure she believed would take 5 hours. (Bissinger reveals that Jenner has not had genital surgery.) She recalls thinking, 'What did I just do? What did I just do to myself?' A counselor from the Los Angeles Gender Center came to the house so Jenner could talk to a professional, and assured her that such reactions were often induced by pain medication, and that second-guessing was human and temporary."

Fossil shows Prehistoric Reptile Gave Birth in Open Ocean

A case of mistaken identity turned out to be the key for proving that a prehistoric aquatic reptile did not lay eggs, but rather gave birth to live young in the warm seas of the Mesozoic.

Former Smithsonian pre-doctoral fellow and prehistoric bird expert Daniel Field, now a researcher at Yale University, was combing through the Yale Peabody Museum of Natural History’s collections of fossilized toothed birds. Coming to a box containing an unknown bird species, Field immediately recognized the bones had been misfiled.

Field saw the tiny jawbone pieces in the box—complete with teeth—and realized they very clearly belonged to a baby-sized version of a swimming reptile known as a mosasaur. Field had worked with adult mosasaur specimens during a paleontological dig earlier in his career.

What’s more, these specimens were collected from deposits from the prehistoric Bear Paw Sea, which once stretched from the Arctic to the Gulf of Mexico. That  gives strong credence to two previous proposals: that mosasaurs lived in the open ocean, not lurking exclusively near coastlines, as previously believed; and that they gave birth to live young.

“It really speaks to the value of the fossil record, that only the fossil record can provide direct evidence of the history of life,” Field says. “It helps us understand what these long-extinct animals would have been like as living, breathing creatures.”

Field added that the marine lizard’s reproductive strategy raises the question of whether mosasaurs and their like were truly cold-blooded in the classic sense. Giving birth to ready-to-swim young in the ocean doesn’t translate to being slow and sluggish like modern reptiles, Field notes.

Collected in Kansas in the late 1800s from the famous Niobrara Formation, the baby mosasaur bones strongly resemble the jaws of unrelated toothed birds in size and shape, and were found in an area where other fossilized birds had been collected. They’d probably been mistaken as bird bones simply due to their size.

Field’s expertise with birds and prior experience with mosasaurs enabled him to identify a distinguishing bulge on the jawbone samples, a structure absent in prehistoric toothed birds. The jawbones belong to a species of mosasaur called Clidastes. Adult specimens have been found 9 feet in length, but these jawbones came from babies no more than 12 inches long. 

Fossils of baby mosasaurs have been found before, but all were etched and pitted as if by acid, indicating they’d been transported to their final resting places in the belly of a predator. The Yale bones showed no such evidence, meaning they’d died of other causes. Field’s discovery fills a puzzling gap in the fossil record.

“Direct evidence of baby mosasaurs in an open marine setting had not yet been found, which is surprising because they had turned up for other groups of marine reptiles,” Field says.

Because of their body structure, researchers had suspected that mosasaurs did not haul themselves out onto a beach to lay eggs, similar to how sea turtles reproduce. Fossilized remains of other prehistoric swimmers, the ichthyosaurs, have been found in the process of giving birth. Some modern relatives of mosasaurs, including monitor lizards and some species of snakes, also skip the eggs.

Why are baby mosasaur fossils rare? Fields points to a variety of likely reasons, including collection bias. Turn-of-the-century fossil hunters were more interested in large, fearsome skeletons for their museums’ collections. They possibly disregarded smaller bones as uninteresting. Also, small-bodied organisms often aren’t preserved as well in the fossil record, due to factors including predation, scavenging, or the bones being smashed and scattered before they can fossilize.

“These fossils have basically waited in the bowels of the Yale Peabody museum for their time to shine,” Field laughed. “People talk about the second round of fossil hunting—everybody knows that paleontologists go into field to dig stuff up, but fossil hunting in museum collections can lead to new insights, too.”  smithsonianscience.si.edu

Field reported his findings in a recent issue of the journal Palaeontology.

ET is a jedi

Lethal Interpersonal Violence in the Middle Pleistocene

Evidence of interpersonal violence has been documented previously in Pleistocene members of the genus Homo, but only very rarely has this been posited as the possible manner of death. Here we report the earliest evidence of lethal interpersonal violence in the hominin fossil record. Cranium 17 recovered from the Sima de los Huesos Middle Pleistocene site shows two clear perimortem depression fractures on the frontal bone, interpreted as being produced by two episodes of localized blunt force trauma. The type of injuries, their location, the strong similarity of the fractures in shape and size, and the different orientations and implied trajectories of the two fractures suggest they were produced with the same object in face-to-face interpersonal conflict. Given that either of the two traumatic events was likely lethal, the presence of multiple blows implies an intention to kill. This finding shows that the lethal interpersonal violence is an ancient human behavior and has important implications for the accumulation of bodies at the site, supporting an anthropic origin. PLOS

Fig 1. Stratigraphy of the Sima de los Huesos site (modified from Arsuaga et al. [21]).

The hominin bones were recovered in Lithostratigraphic Unit 6 (LU-6) dated to c. 430ka [21]. This unit is composed of pure red clays, filtering into the conduit system from overlying soils with little or no lateral transport, and very low velocity of sedimentation (decantation by dripping water) [23]. The figure also shows a detailed image of Cr-17 during its excavation at the site. Note the pure red clay that covers the cranial bones (partially cleaned in situ to enhance visualization) and the typical in situ postmortem (fossil diagenetic) fractures of the cranial vault. Photo credit: Javier Trueba (Madrid Scientific Films).

The skull in question was found at a site in Spain called Sima de los Huesos, or the Pit of the Bones, and it contained remains of 28 individuals. Quam said their presence there was intentional. "The only explanation that we have that can not be rejected is the idea that the human bodies arrived at this place by other humans," Quam told NPR. npr

bugs for dinner- more sustainable than meat

In the last couple of years, we've detected a faint buzz about crispy crickets and crunchy mealworms. Companies pedaling scorpion lollipops and peanut butter-and-jelly protein bars made with cricket flour have thrust their wares into our hands and mailboxes.

It's truly gotten easier to snack on bugs, should you want to do so. And everyone from the earnest eco-entrepreneurs in towns like Austin and Boulder, to international luminaries like Kofi Annan to the Food and Agriculture Organization are raving about how sustainable bugs are compared to meat.

But that doesn't mean the Western world, which doesn't have much of a history of entomophagy, is biting. Much.

Ophelia Deroy, a British researcher, tells The Salt most Westerners she has surveyed in randomized studies say they've hardly ever eaten insects in their life. And in a short column published Wednesday in Nature, she explains her hunch as to why the call to eat insects for nutritional and environmental reasons isn't being widely heeded yet.

Policymakers and the media have assumed that Westerners are disgusted by bugs because we associate them with contamination and disease. So the focus has been on trying to convert the uninitiated by making an environmental case for insect cuisine, and by noting that 2 billion people in around 100 countries (like Thailand) already enjoy many different insects in a range of dishes, Deroy writes.

Instead, Deroy argues, "We should think less about combating disgust and more about appealing to taste."

Sushi entrepreneur Peter Yung makes an Insectopia Roll at the Future Food Salon in Austin, Texas, in February 2014. A British researcher writes that chefs and others must "make insect dishes appeal as food, not just a way to save the planet."

So what does that mean? Well, Deroy, who's at the Centre for the Study of the Senses at the University of London, thinks it's about making the experience of eating them more enjoyable and less scary. For her, that happened when she tried crickets sprayed with a "beautiful golden dust" on the side of a salad.

It's true that many insects may not be especially enticing at a sensory level, at least at first: They're dry, and their wings and legs may crumble strangely in your mouth.

But there are other ways around this that don't involve visual seduction with gold dust. Last summer, we attended an event called the "Pestaurant" that featured turkey burgers with ground-up and whole grasshoppers. As we reported, the burgers were juicy and full of flavor, thanks, in part, to a brilliant secret ingredient: duck fat. We watched as many skeptics gobbled the burgers, clearly happy to accept the unfamiliar addition to the succulent dish.

Entomophagists agree that bugs will need some culinary champions to really go big.

"Chefs (and their celebrity diners) will have to play a leading role in making crickets (or any other edible insects) attractive and desirable, in the same way that California chefs turned dangerous and disgusting raw fish into sushi, the dish of Hollywood elites," Robert Nathan Allen, founder of Little Herds, a group that's working to grow the market for edible bugs, tells The Salt in an email.

Deroy thinks some insects could also stand to be re-named, a la the Chilean sea bass (formerly Patagonian toothfish). And indeed, there have been efforts to rename locusts "sky prawns" to make them more appetizing.

"And we should not forget those with a sweet tooth: many insects lend themselves naturally to desserts," she writes.

Bee ice cream, maybe? There's got to be more to insect sweets than those scorpion lollipops, which are not going to be for everyone.

"Appealing to logic and morality only gets you so far," says Allen. "We need to make it desirable and affordable before we can hope to change the minds (and tastebuds) of the average American. "

NOAA's hurricane season outlook

" 'A below-normal season doesn't mean we're off the hook. As we've seen before, below-normal seasons can still produce catastrophic impacts to communities," said NOAA Administrator Kathryn Sullivan, Ph.D., referring to the 1992 season in which only seven named storms formed, yet the first was Andrew – a Category 5 Major Hurricane that devastated South Florida."

BTW- hurricane season starts June 1st!

mary ellen mark

http://www.maryellenmark.com/

DNA evidence suggests that the split between dogs and their wild ancestors occurred closer to 30,000 years ago

It looks like dogs might well have been man's (and woman's) best friend for a lot longer than once thought.

The long-held conventional wisdom is that canis lupus familiaris split from wolves 11,000 to 16,000 years ago and that the divergence was helped along by Stone Age humans who wanted a fellow hunter, a sentry and a companion.

Now, DNA evidence suggests that the split between dogs and their wild ancestors occurred closer to 30,000 years ago.

Publishing in Thursday's edition of Current Biology, the authors of a new study looked at the genome of a 35,000-year-old wolf from the Taimyr Peninsula in northern Siberia. "We find that this individual belonged to a population that diverged from the common ancestor of present-day wolves and dogs very close in time to the appearance of the domestic dog lineage," they wrote in the abstract.

The team, led by Pontus Skoglun, a research fellow at Harvard, concluded that the mutation rate for canines is "substantially slower than assumed by most previous studies, suggesting that the ancestors of dogs were separated from present-day wolves before the Last Glacial Maximum."

In other words, there may have been a faithful Fido walking with a human before the end of the last Ice Age (and before agriculture).

As The New York Times writes: "Based on the differences between the genome of the new species, called the Taimyr wolf, and the genomes of modern wolves and dogs, the researchers built a family tree that shows wolves and dogs splitting much earlier than the 11,000 to 16,000 years ago that a study in 2014 concluded."

However, a study reported in 2013 places the date of the canine split closer to the study published on Thursday. As NPR's Nell Greenfieldboyce reported then, a team headed by Robert Wayne, a biologist at the University of California, Los Angeles, and publishing in Science, used DNA analysis to peg the date at somewhere between 18,800 to 32,100 years ago.

In the new study, an author of the report was quoted by the Times as saying the simplest explanation for the new data is that dogs were domesticated as much as 30,000 years ago, but he cautions that the study does not prove it. "We can't just look at the DNA and say whether a canid was living with modern humans," he was quoted by the newspaper as saying.

"One scenario is that wolves started following humans around and domesticated themselves," Dalen told BBC. "Another is that early humans simply caught wolf cubs and kept them as pets and this gradually led to these wild wolves being domesticated. If this model is correct then dogs were domesticated by hunter gatherers that led a fairly nomadic lifestyle." npr

Census Reveals Universe Of Marine Microbes At Bottom Of The Food Chain

What's at the bottom of the bottom of the food chain? Well, think small ... smaller than you can see.

Microbes in the ocean!

There are (and scientists have done the math) trillions of microorganisms in the ocean: plankton, bacteria, krill (they're maybe bigger than "micro," but not by much), viruses, protists and archaea (they're like bacteria, but they aren't bacteria).

The Earth as we know it wouldn't exist without the trillions of microorganisms that live in the oceans. They're food for most everything that floats or swims, and they make oxygen that we need to breathe.

Now scientists have completed a census of this Lilliputian universe. And it's more diverse than anyone imagined.

Like Charles Darwin and other naturalists of the 18th and 19th century, the modern explorers spent years sailing around the world to accomplish this feat. They called their expedition Tara, after the name of the 110-foot schooner on which they lived for three years. 

The scientists aboard found more than 35,000 different kinds of organisms — many of them previously unknown to science. Their work fills five papers in the journalScience. Journal editor Marcia McNutt says it's time the world took notice of what wecan't see in the ocean.

"How can we save the whales if we can't save the krill?" she says. "There's something about the tragedy of the commons here."

Oceans are dumping grounds for the world's garbage. Climate change is making them warmer and more acidic. The Tara expedition was designed to measure what's out there and how it might be affected by a changing ocean.

To do that, the scientists siphoned up ocean water and used DNA probes to identify the organisms in the water. That also enabled them to understand how those organisms behave: eat, reproduce, interact.

Team scientist Eric Karsenti, from the European Molecular Biology Laboratory, says he was surprised by how much these tiny organisms interact with each other, often in symbiotic relationships.

"It's not only survival of the fittest," he says, "but it's also how everybody collaborates with everybody else that makes life evolve."

They also discovered communities of organisms caught up in big eddies, like whirlpools. These eddies carry these little living eco-systems with them across the oceans. The researchers also found these microorganisms to be exquisitely sensitive to temperature changes. And in fact, the oceans already are warming due to climate change.

Steve Palumbi, a marine biologist at Stanford University, says all this is good reason to pay more attention to these microbes.

"Anything that goes on in that region of life, that bottom layer, these tiny things makes a big difference to how the planet functions," he says.

Not only are they food for so much of what lives in the ocean, but they add huge amounts of oxygen to the atmosphere. "Anywhere between 1 in 4 and 1 in 2 breaths we take comes out of the ocean," says Palumbi. And that's mostly coming from these tiny little microbes.

Palumbi says this scientific bite at the oceanic apple will take years for scientists to digest. But he notes that the Tara scientists have made the unusual gesture of giving anyone in the world access to their data — in the hope that many hands will make quick work of it. npr

Dense Breasts Are Just One Part Of The Cancer Risk Calculus

Almost half the states now require doctors to tell women if they have dense breasts because they're at higher risk of breast cancer, and those cancers are harder to find. But not all women with dense breasts have the same risks, a study says.

Those differences need to be taken into account when figuring out each woman's risk of breast cancer, the study says, and also weighed against other factors, including family history, age and ethnicity.

The researchers looked at the records of 365,426 women who had a normal mammogram, then looked to see which ones were diagnosed with breast cancer within a year — a cancer that may have been missed by the mammogram.

All told, 47 percent of the women in the study had dense breasts. But just half of those women had a higher cancer risk. The women who got cancer were more likely to be older and white, have a family history of breast cancer, and to have "heterogeneously" or "extremely" dense breasts, the top two categories of breast density.

The results were published Monday in Annals of Internal Medicine. npr