Courtesy M. R. Smith / Smithsonian InstituteOne of the strangest and more mysterious critters that scurried across the Middle Cambrian seafloor has baffled paleontologist since it was first identified in the 1970s. Was it a worm? Which side was up? Did it have legs or spikes or both? Was its head actually its tail? Did it have any extant descendents or was it an evolutionary dead-end? The worm-like creature was so baffling and so bizarre, it was given the very apropos name of Hallucigenia.
The tubular, spiked-worm possessed seven or eight pairs of legs and ranged in length from 2/5th of an inch to one and 1/4 inches and looks like something out of a bad dream. Early interpretations of their fossils were all over the map. The stiff spikes on it back were first thought to be its legs, and its legs misidentified as tentacles. What was thought to be its tail ended up being its head.
Using modern imaging technology, researchers from the University of Cambridge have been closely studying fossils from the famous Burgess Shale quarry located high in the Canadian Rockies, and are uncovering Hallucigenia's secrets. By studying the claws at the end of its legs they have been able to link it to modern velvet worms (onychophorans). Scientists have long suspected the two were somehow related but until now have failed to find anything significant to prove it. By studying Hallucigenia's claws they've determined that they're constructed of nested cuticle layers, very similar to how the jaws of velvet worms are organized. The similarity is no surprise since jaws are known to have evolved from a modified set of front legs.
But besides giving Hallucigenia a place in the lineage of life on Earth, the Cambridge team during the course of their study also discovered something else: that arthropods - which include crustaceans, spiders, insects and trilobites - aren't in fact as closely related to velvet worms as previously thought.
“Most gene-based studies suggest that arthropods and velvet worms are closely related to each other," said co-author Dr Javier Ortega-Hernandez. "However, our results indicate that arthropods are actually closer to water bears, or tardigrades, a group of hardy microscopic animals best known for being able to survive the vacuum of space and sub-zero temperatures – leaving velvet worms as distant cousins.”
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Courtesy Luis Miguel Bugallo SánchezThey're the favorite punching bags and punchlines for politicians and late night comics: those seemingly odd science research projects. Right now there's a turmoil over a National Science Foundation grant of some $385,000 to study the genitalia of ducks.
The Washington Post today digs deeper into these kinds of projects. Are they frivolous? Do they lead to deeper scientific findings? If the government doesn't provide the funding, would anybody else? Does the government have a obligation to help provide opportunities for such research to happen? Who and how do we decide if a study is worth funding for the greater good of society? They're all interesting questions.
One of the problems of the past, the article notes, is that scientists typically have kept quiet and take their lumps from the critics while their research goes on. The thinking is that the critics don't want to understand science, so why even engage them in an argument. And unknown benefits can emerge from such projects. A researcher looking into why bluebirds are blue is now on the cusp of developing a new way to make paint.
It's a great topic for debate. Read the article and share your thoughts here with other Science Buzz readers.
Courtesy Twin Cities NaturalistIt may not feel like it but rest assured, this is December. Check out this week's Phenology Roundup where professional naturalist Kirk Mona of Twin Cities Naturalist discusses what was seen around the Twin Cities area in the past week.
Phenology is the science of the seasons. It looks at how and when nature changes according to seasonal climatic conditions.
"This toilet floats. It's an outhouse and sewage-treatment plant in one, processing human waste through a "constructed wetlands." Green builder Adam Katzman, the inventor and builder of the toilet-boat, says it's meant to be more inspirational than practical. His paddle-boat-toilet ("Poop and Paddle"), parked at a marina in Queens, demonstrates how sewage and rainwater can be converted to cattails and clean water. It's a zero-waste waste disposal system."
Courtesy IneuwWe love whale poop around here. Love it love it love it. Can’t get enough. It’s fortunate for us that whales poop so much—if you were to get the planet’s daily supply of whale poop in one place, and if you were also in that place, you would suffocate. It’d be awful.
The reason we love whale poop so much is because of its role in what Elton John and I like to call “the circle of life.”
We’ve already discussed how sperm whales have a net negative contribution to atmospheric CO2, because of all the iron in their poop. (The iron rich waste feeds tiny sea creatures, which, in turn, suck up CO2.)
It turns out that whales and their poop are also vital for the nitrogen cycle. Nitrogen is a vital nutrient for ocean life. While some parts of the ocean have too much nitrogen—extra nitrogen from fertilizers washes out through rivers, causing algae to grow out of control and create a dead zone—other areas contain a very small amount nitrogen, and local ecosystem productivity is limited by nitrogen availability.
So what brings more nitrogen to these nitrogen-poor areas? Microorganisms and fish bring it from other parts of the ocean, and release it by dying or going to the bathroom. But, also… whales bring it. Whales bring it by the crapload.
Whales, it turns out, probably play a very heavy role in the nitrogen cycle. And because the nitrogen feeds tiny ocean creatures, and those tiny ocean creatures feed larger ocean creatures, and on and on until we get to fish, more whales (and whale poop) means more fish. And we (humans) love fish.
Commercial whaling over the last several hundred years reduced global whale population to a small fraction of what it once was, but even at their current numbers whales contribute significantly to nitrogen levels in some areas. More whales, the authors of a recent whale poop study say, could help offset the damage humans have done to the oceans and ocean fisheries, while relaxing restrictions on whaling could have much further reaching ramifications than we might expect.
See? Whale poop is the best! (Whales too, I guess.)
Courtesy kqedquestWe’ve talked about the delights of cow feces before on Science Buzz, but mid-July always puts me in the mind of “brown gold” (coincidentally, the last occasion it came up was exactly four years ago today), and any time there’s talk of turning an animal into a fuel source, I get excited. (Remember that fuel cell that ran on the tears of lab monkeys? Like that.) Why not take another look?
So here you are: another wonderful story of cows trying their best to please us, before they make the ultimate gift of allowing their bodies to be processed into hamburgers and gelatin and cool jackets.
Poop jokes aside (j/k—that’s impossible), it is a pretty interesting story. The smell you detect coming from cattle farms is, of course, largely from the tens of thousands of gallons of poop the cattle produce every day. The decomposing feces release lots of stinky methane. (Or, to be more precise, the methane itself isn’t smelly. The bad smell comes from other chemicals, like methanethiol, produced by poop-eating bacteria along with the methane.)
Aside from being, you know, gross, all of that poop is pretty bad for the environment. The methane is released into the atmosphere, where it traps heat and contributes to global warming (methane is 20 to 50 times more potent than carbon dioxide as a greenhouse gas), and the poop itself is spread onto fields as fertilizer. Re-using the poop as fertilizer is mostly a good idea, but not all of it gets absorbed into the soil, and lots of it ends up getting washed away into rivers, lakes, and streams, where it pollutes the water.
Some farms have managed to address all of these problems, and make money while doing it.
Instead of spreading the manure onto fields right away, the farms funnel all the poop into swimming pool-sized holding tanks, where it is mixed around and just sort of stewed for a few weeks. All of the methane gas produced by bacteria as it breaks down the manure is captured in tanks. What’s left is a fluffy, more or less sterile, solid that can be used as bedding for the animals, or mixed in with soil, and a liquid fertilizer that can be spread onto fields.
The methane can then be used on-site to generate electricity, either by burning it in a generator, or using it in a fuel cell. (The methane is broken apart and combined with oxygen from the air to produce electricity, water, and carbon dioxide.) A large farm will produce enough electricity to power itself and several hundred other houses. (The extra electricity is just put back into the power grid and sold to the power company.)
Whether the methane is burned or used in a fuel cell, the process still creates carbon dioxide. However, CO2 isn’t nearly as bad as methane when it comes to trapping heat, and because the original source of the carbon was from plant-based feed, the process can be considered “carbon-neutral.” (Although one might argue that the fossil fuels involved in other steps of the cattle farming process could offset this. But let’s leave that be for now. It’s complicated.)
The downside is that setting up an operation to capture and process manure, and to generate power by burning it is expensive—it took about 2.2 million dollars to do it at the farm covered in the article, with about a third of that coming from grants. Still, the byproducts (electricity, fertilizer, soil/bedding) are profitable enough that the system could pay for itself over the course of a few years.
It’s amazing, eh? Out of a cow’s butt we get soft, clean bedding, liquid fertilizer, and electricity, all without the bad smell. What a world.
I'd say "In case you were wondering exactly how astronauts go to the bathroom in space," except... of course you were wondering that. Thankfully, there's this video to walk you though it, from the alignment camera on the practice toilet, to the thigh restraints and the frightening, hissing pipes of the real thing.
PS—And what about those "Apollo fecal bags"? How come those weren't in Apollo 13 (the movie, not the mission)?
Courtesy esteraseI bet regular bacteria have posters of their favorite superbug hung on their bedroom walls. I mean superbugs are just so much cooler than regular bacteria; they’re kind of the bad boys of the bacteria world. Regular bacteria do what they are told: they keel over when exposed to disinfectants and antibiotics. But not those rebellious superbugs. Superbugs have some kind of genetic mutation that allows them to survive in hostile, antimicrobial environments. Basic principles of natural selection come into play: the mutant bacterium survives in the presence of the antibiotic/disinfectant and then goes on to produce other bacteria with the same mutation, ultimately creating a new resistant colony. In this scenario, exposure to the antimicrobial agent (the antibiotic or disinfectant) is imperative. However, scientists now think that another scenario exists; one in which exposure is not required. In a recent study, these scientists found that the use of disinfectants in hospitals can lead to bacterial resistance to antibiotics, even if the bacteria haven’t been exposed to the antibiotics.
Researchers from the National University of Ireland added increasing amounts of disinfectant to petri dishes full of Pseudomonas aeruginosa (a bug that causes pneumonia in hospital patients, among other things) and the bug became immune not only to the disinfectant, but also to ciprofloxacin- the antibiotic used to treat the bug. Superbugs are essentially using their exposure to disinfectants as “teachable moments” for resisting antibiotics.
This is significant because now it seems that bacteria have one less hurdle to overcome in their mission to cause serious harm to patients (that’s not really their “mission,” I say that for dramatic effect). If superbugs can resist the disinfectant slathered on the countertops and doorknobs of hospitals, it’s possible that they could go on to infect patients who “for some reason” won’t respond to the antibiotics. Man, regular bacteria must be so jealous.