![sagansense:
Ancient DNA Found Hidden Below Sea Floor
In the middle of the South Atlantic, there’s a patch of sea almost devoid of life. There are no birds, few fish, not even much plankton. But researchers report that they’ve found buried treasure under the empty waters: ancient DNA hidden in the muck of the sea floor, which lies 5000 meters below the waves. The DNA, from tiny, one-celled sea creatures that lived up to 32,500 years ago, is the first to be recovered from the abyssal plains, the deep-sea bottoms that cover huge stretches of Earth. In a separate finding published this week, another research team reports teasing out plankton DNA that’s up to 11,400 years old from the floor of the much shallower Black Sea. The researchers say that the ability to retrieve such old DNA from such large stretches of the planet’s surface could help reveal everything from ancient climate to the evolutionary ecology of the seas.
“We have been able to show that the deep sea is the largest long-time archive of DNA, and a major window to study past biodiversity,” writes Pedro Martinez Arbizu, a deep-sea biologist of the German Centre for Marine Biodiversity Research in Wilhelmshaven and an author of the paper on South Atlantic DNA in an e-mail.
The new studies are “very exciting,” says micropaleontologist Bridget Wade of the University of Leeds in the United Kingdom, who was not connected to the research. Until now, it wasn’t clear “how far back in time you could take these DNA studies. … These records are telling you new information that wasn’t found in the fossil record.”
The South Atlantic team went looking for DNA in plugs of silt and clay coaxed out of the ocean floor hundreds of kilometers off the Brazilian coast. The researchers were after genetic material from two related groups of marine organisms, the foraminifera and the radiolarians. Both are single-celled, and both include many species with beautiful pearly shells that fossilize nicely, making them a favorite target of researchers studying the prehistoric oceans.
The researchers used special pieces of DNA specific to radiolarians and foraminifera to fish out DNA from those groups. Then they sequenced the DNA and compared the results to known foraminifera and radiolarian DNA sequences. Their analysis showed they’d found 169 foraminifera species and 21 radiolarian species, many of which were unknown. What’s more, many of the foraminifera species belonged to groups that don’t form fossils, the researchers report online today in Biology Letters.
The work shows that it’s possible to trace all species, not just those that fossilize, says Jan Pawlowski, a foraminifera specialist and one of the paper’s authors, of the University of Geneva in Switzerland. The results give “us a completely different view … [that] may open new insights into what’s happened in the past,” he says. For example, he says, different species of these wee creatures prefer different water temperatures. So DNA from buried sediments could be used to track the abundance of different species over time, revealing changes in ocean temperature.
The second team looked at DNA buried in the floor of the Black Sea, which was once a giant lake but became connected to the Mediterranean Sea roughly 9000 years ago, though the date is debated. The researchers examined sediments from waters only 980 meters deep, which is much shallower than the abyssal plain. But the oldest Black Sea layers that were analyzed were similar to those at the South Atlantic site: The mud at the sea bottom had scant amounts of organic matter and had been exposed to oxygen, which, in theory, should have made it tough to scrape up any preserved DNA.
It didn’t. New material had buried the older layers, cutting off their oxygen, and more recent Black Sea sediments weren’t exposed to oxygen at all. The result was a rich trove of ancient DNA from as many as 2700 species, including green algae, fungi, and dinoflagellates, a type of one-celled aquatic creature. The diverse collection allowed the scientists to track the fate of different species over time, as their DNA blinked in and out of the sediments.
One type of marine fungus, for example, first appeared in the sediments roughly 9600 years ago—exactly when some forms of freshwater plankton and a freshwater mussel vanish, the team reports this week in the Proceedings of the National Academy of Sciences. That suggests that marine waters started to invade the lake roughly 600 years earlier than thought. The team also found DNA from a form of marine alga in 9300-year-old sediments, though the alga doesn’t show up in the fossil record until 2500 years ago, says molecular paleoecologist Marco Coolen of the Woods Hole Oceanographic Institution in Massachusetts and an author of the Black Sea paper.
Other ancient DNA studies have been discredited after supposedly ancient genetic material turned out to be modern contaminants, but those fears don’t apply to this new research, says micropaleontologist Michal Kucera of the University of Bremen in Germany. He says that both teams took the necessary steps to avoid contamination, and their results don’t look like contaminants. In the Biology Letters results, for instance, DNA from older sediments is more degraded than material from more recent sediment—not what you’d expect if the DNA were a laboratory stowaway.
Kucera and Wade praised both studies as paving the way for the use of ancient marine DNA to illuminate the history of the ocean. Coolen’s finding of marine species invading the Black Sea earlier than had been thought “is not something you could see from looking at fossils or sediment properties,” Kucera says.
Wade says that it may be possible, once researchers can identify the DNA of species that prefer certain environmental conditions, to use deep-water DNA to reveal changes in climate. “Most of the environment on Earth is marine deep ocean,” including the area where Pawlowski’s team found DNA, she says. “So it makes it very exciting that they’re looking in this environment and finding DNA.”
image: Minute fossil sea creatures recovered from sediments containing ancient DNA. credit: Lejzerowicz et al./Biology Letters](http://25.media.tumblr.com/9136c906c2e4e9ed102b1bae66ff810a/tumblr_mmro1yDxzq1r01w8mo1_500.jpg)
Ancient DNA Found Hidden Below Sea Floor
In the middle of the South Atlantic, there’s a patch of sea almost devoid of life. There are no birds, few fish, not even much plankton. But researchers report that they’ve found buried treasure under the empty waters: ancient DNA hidden in the muck of the sea floor, which lies 5000 meters below the waves.
The DNA, from tiny, one-celled sea creatures that lived up to 32,500 years ago, is the first to be recovered from the abyssal plains, the deep-sea bottoms that cover huge stretches of Earth. In a separate finding published this week, another research team reports teasing out plankton DNA that’s up to 11,400 years old from the floor of the much shallower Black Sea. The researchers say that the ability to retrieve such old DNA from such large stretches of the planet’s surface could help reveal everything from ancient climate to the evolutionary ecology of the seas.“We have been able to show that the deep sea is the largest long-time archive of DNA, and a major window to study past biodiversity,” writes Pedro Martinez Arbizu, a deep-sea biologist of the German Centre for Marine Biodiversity Research in Wilhelmshaven and an author of the paper on South Atlantic DNA in an e-mail.
The new studies are “very exciting,” says micropaleontologist Bridget Wade of the University of Leeds in the United Kingdom, who was not connected to the research. Until now, it wasn’t clear “how far back in time you could take these DNA studies. … These records are telling you new information that wasn’t found in the fossil record.”
The South Atlantic team went looking for DNA in plugs of silt and clay coaxed out of the ocean floor hundreds of kilometers off the Brazilian coast. The researchers were after genetic material from two related groups of marine organisms, the foraminifera and the radiolarians. Both are single-celled, and both include many species with beautiful pearly shells that fossilize nicely, making them a favorite target of researchers studying the prehistoric oceans.
The researchers used special pieces of DNA specific to radiolarians and foraminifera to fish out DNA from those groups. Then they sequenced the DNA and compared the results to known foraminifera and radiolarian DNA sequences. Their analysis showed they’d found 169 foraminifera species and 21 radiolarian species, many of which were unknown. What’s more, many of the foraminifera species belonged to groups that don’t form fossils, the researchers report online today in Biology Letters.
The work shows that it’s possible to trace all species, not just those that fossilize, says Jan Pawlowski, a foraminifera specialist and one of the paper’s authors, of the University of Geneva in Switzerland. The results give “us a completely different view … [that] may open new insights into what’s happened in the past,” he says. For example, he says, different species of these wee creatures prefer different water temperatures. So DNA from buried sediments could be used to track the abundance of different species over time, revealing changes in ocean temperature.
The second team looked at DNA buried in the floor of the Black Sea, which was once a giant lake but became connected to the Mediterranean Sea roughly 9000 years ago, though the date is debated. The researchers examined sediments from waters only 980 meters deep, which is much shallower than the abyssal plain. But the oldest Black Sea layers that were analyzed were similar to those at the South Atlantic site: The mud at the sea bottom had scant amounts of organic matter and had been exposed to oxygen, which, in theory, should have made it tough to scrape up any preserved DNA.
It didn’t. New material had buried the older layers, cutting off their oxygen, and more recent Black Sea sediments weren’t exposed to oxygen at all. The result was a rich trove of ancient DNA from as many as 2700 species, including green algae, fungi, and dinoflagellates, a type of one-celled aquatic creature. The diverse collection allowed the scientists to track the fate of different species over time, as their DNA blinked in and out of the sediments.
One type of marine fungus, for example, first appeared in the sediments roughly 9600 years ago—exactly when some forms of freshwater plankton and a freshwater mussel vanish, the team reports this week in the Proceedings of the National Academy of Sciences. That suggests that marine waters started to invade the lake roughly 600 years earlier than thought. The team also found DNA from a form of marine alga in 9300-year-old sediments, though the alga doesn’t show up in the fossil record until 2500 years ago, says molecular paleoecologist Marco Coolen of the Woods Hole Oceanographic Institution in Massachusetts and an author of the Black Sea paper.
Other ancient DNA studies have been discredited after supposedly ancient genetic material turned out to be modern contaminants, but those fears don’t apply to this new research, says micropaleontologist Michal Kucera of the University of Bremen in Germany. He says that both teams took the necessary steps to avoid contamination, and their results don’t look like contaminants. In the Biology Letters results, for instance, DNA from older sediments is more degraded than material from more recent sediment—not what you’d expect if the DNA were a laboratory stowaway.
Kucera and Wade praised both studies as paving the way for the use of ancient marine DNA to illuminate the history of the ocean. Coolen’s finding of marine species invading the Black Sea earlier than had been thought “is not something you could see from looking at fossils or sediment properties,” Kucera says.
Wade says that it may be possible, once researchers can identify the DNA of species that prefer certain environmental conditions, to use deep-water DNA to reveal changes in climate. “Most of the environment on Earth is marine deep ocean,” including the area where Pawlowski’s team found DNA, she says. “So it makes it very exciting that they’re looking in this environment and finding DNA.”
image: Minute fossil sea creatures recovered from sediments containing ancient DNA. credit: Lejzerowicz et al./Biology Letters
(via taylor-renee)
♡♡♡♡♡♡♡♡
LAYER ONE: THE OUTSIDE
- Name: Lantur!
- Eye Color: Dark brown.
- Hair Style/Color: My hair is a blackish brown color. It’s long-ish and wavy, and I want to keep growing it until it’s waist-length. Cersei Lannister is my hair inspiration!
- Height: 4’10
- Clothing style: Eclectic.
- Best physical feature: Uh…face?LAYER TWO: THE INSIDE
- Your fears: Spiders, bugs, the dark, murderers, rapists, terrorists, violent people in general.
- Your guilty pleasure: I have no guilty pleasures, I’m not ashamed of anything I like.
- Ambitions for the future: At the moment, getting a PhD in Disability Studies and teaching at a university and/or running a campus Disability Resource Center, like my favorite professor!LAYER THREE: THOUGHTS
- Your first thoughts waking up: I want to go back to sleep. What time is it?
- What you think about most: Food and dogs.
- What you think about before bed: Writing fanfiction in my head. :)
- You think your best quality is: I write good.LAYER FOUR: WHAT’S BETTER?
- Single or group dates: Ha, uh, it’s been a long time since I was on either. I enjoy group dates a lot.
- To be loved or respected: Both, if possible, but I’d go with “respected.”
- Beauty or brains: A good heart is what’s most important. You can be not the smartest person and have a good heart. You can be attractive or unattractive, and if you have a good heart, that’s what makes you a desirable and worthwhile person.
- Dogs or cats: DOGS DOGS DOGSLAYER FIVE: DO YOU?
- Lie: I used to, but not anymore.
- Believe in yourself: Yes.
- Believe in love: Of course!
- Want someone: Nobody in particular at the moment, but all of the male medical students I volunteer with are great! They’re good-looking and nice.LAYER SIX: EVER?
- Been on stage: Yeah, I used to do spelling bees when I was a kid, and violin and band recitals and stuff. Also, I walked across the stage when I graduated, haha.
- Done drugs: Nah, the only thing I’ve smoked is hookah.
- Changed who you were to fit in: Yes, in high school.LAYER SEVEN: FAVORITES
- Favorite color: Dark purple.
- Favorite animal: Dogs and tigers.
- Favorite movie: Slumdog Millionaire, 3 Idiots.
- Favorite game: Wheelchair hockey.LAYER EIGHT: AGE
- Day your next birthday will be: November 26.
- How old will you be: 21
- Age you lost your virginity: 40
- Does age matter: I wouldn’t want to date anyone younger than me, or more than a few years older.LAYER NINE: IN A BOY OR GIRL
- Best personality: Caring, compassionate, humorous, intelligent, adventurous.
- Best eye color: Brown
- Best hair color: Brown or black.
- Best thing to do with a partner: Eat food, go on adventures, travel and explore new frontiers.LAYER TEN: FINISH THE SENTENCE
- I love: myself
- I feel: Content!
- I hide: The fact that I am often oversensitive and care about what people think of me, despite the “give no fucks” attitude I often project.
- I miss: One of my friends, who I haven’t seen in a while. EMILY
- I wish: I didn’t need laser hair removal in awkward areas, because of side effects from my polycystic ovarian syndrome. :(
(Source: languidcrow, via slumdog-smart)
you can ship something and
- still understand and respect that a particular character wouldn’t be into the relationship at that point in time or ever
- accept it if the characters never get together in canon
- be completely fine with other people not shipping it
- not hate the characters’ canon relationships or romantic/sexual partners
- realize that being in a sexual/romantic relationship with the other character(s), or with anyone at all, might not be healthy for one or both of the characters
- if the characters are already in a sexual/romantic relationship with each other, acknowledge that there are things about that relationship that are fucked up and unhealthy
- admit each character’s faults honestly and not excuse them (understanding =/= excusing)
- differentiate between what you want to see in canon and what you want to write/read about in fic/see in art
- understand that ships serve different needs for different people; not every ship or representation of a ship is about healthy, loving romantic relationships. Some ships are about unhealthy codependency; some are about hatesex. Ships are a way of working out fantasies that we can’t and sometimes shouldn’t fulfill in real life, or about working through real-life fears, hopes, and pains. Writing something is not tantamount to saying “this is 100% awesome”. Sometimes we have to indulge our ids, and that doesn’t mean we get a free pass to not think about issues of representation or ensure that the people reading our fics know what to expect, but it all comes down to, for me, the fact that life is too fucking short and painful to have to feel like shit for what goes on in our heads so long as it doesn’t hurt anyone else.
this is relevant to my interests
(Source: stormdicks, via disgruntledturtle)
So today Angelina Jolie had double mastectomy, which is the removal of one’s breasts, to prevent Breast cancer. So instead of praising Angelina on her bravery, men on Twitter decided to ridicule her, even calling her stupid for removing her breasts. For those of you on Tumblr that are attacking Feminists about being delusional about sexism against women and misogyny here’s your fucking proof that sexism and misogyny exists.
(via bleibimmerduselbst)
Anonymous asked: WOW, I just lost a bunch of weight using the OFFICIAL TUMBLR DIET!! Are u using it as well?
I saw the “1” over my inbox, and I got all excited, and then it was THIS. D: Watch yourself, tumblrbot. You have displeased me.
oh my god so i was at the store today and there was a younger blind guy with his sister or cousin or something and i was walking behind him by a little kid and his mom and the little kid was like “mommy why is he walking with a stick?” and the mom goes “shh..he’s blind sweetie” and the guy turns around and he goes “yeah blind to the haters” and just turns around and starts walking again and I sTARTED LAUGHING SO HARD IT WAS HILARIOUS
(via morganalefay)
son these grades are unacceptable
well maybe if you’d stop eating my fucking homework dad
(via howlsgroovincastle)
If your parents ever walk into your room.
Open this link.
Then pretend to type.
Instant Essay!
Anonymous asked: Hey Lantur! How is the next part of Strings coming along?
Hi anon! It’s…coming. It’s shaping up to be an extremely long chapter, because it’s the big climactic chapter. Everything after this will just be the story wrapping up. I keep rewriting scenes and tweaking the outline, because I want it to come out well. I’m sorry for how long it’s taken, I wasn’t able to do consistent work on it until about a week ago.
"You don’t need religion to have morals. If you can’t determine right from wrong then you lack empathy, not religion."
Unknown (via bokononish)
(Source: copulati0n, via adultsupervisionpls)
I had a great day today. JAWS, the program that I volunteer with, hosted a big event at the park for most of the day, designed to show appreciation for people with disabilities and their friends, families, and/or caregivers. We hand-cycled and biked around the park, played games, and had a barbecue for lunch. I’m wiped out from biking around 4 miles and lifting, dragging, and loading and unloading handcycles into and out of the storage center on campus, and onto and off of trucks - but it was a lot of fun. I got to hang out with a lot of cool kids, adults, and the medical student volunteers.
The long bike ride was enjoyable, too. It’s the longest distance I’ve ever biked, and it was like 90 degrees out today, but it was still nice. It’s fun to get away from technology and the indoors, and go catch some sunshine and do some physical activity - especially in the company of other people. I exercise regularly, but it’s always indoors at a gym, and there’s something nice about seeing the blue sky, green grass and trees, and feeling the breeze and fresh air on your face.
Also, one of the best things about today was that I got to meet and pet THREE new dogs. That’s right, three. Two of the kids brought their service dogs, and one of the other volunteers bought her dog. All of them were so nice, and they really liked me. One of the dogs was this massive St. Bernard that weighed 117 pounds!
And after I got home, I took my dog on a walk, and we chased rabbits and I made her jog with me for a little while. Well, I jogged, and she trotted frantically behind me, struggling to keep up on her little legs. :D
So today was a good dog day, and an excellent day overall. I am so happy that I have the opportunity to be involved with fun volunteer activities like these.
The Lakes of Mount Kelimutu, Indonesia are considered to be the resting place for departed souls, the lakes are locally referred to as “the lake of evil spirits”. All 3 lakes change colour from blue to green to black or red unpredictably.
(via taylor-renee)
"People get really irritated by mental illness. “Just fucking get it together! Suck it up, man!” I had a breakdown, and a spiritual friend came to visit me in the psych ward. And they said, “You need to get out of here. Because this is the story you’re telling yourself. You know, Patch Adams has this great work-group camp where you can learn how to really celebrate life.”
It’s something people are so powerless over, and so often they want to make it your fault. It’s nobody’s fault. I started thinking of suicide when I was 10 years old—I can’t believe that that’s somebody’s fault. Like, “Oh, you’re just an attention getter.” Mental illness isn’t seen as an illness, it’s seen as a choice.
I have a joke about how people don’t talk about mental illness the way they do other regular illnesses. “Well, apparently Jeff has cancer. Uh, I have cancer. We all have cancer. You go to chemotherapy you get it taken care of, am I right? You get back to work.” Or: “I was dating this chick, and three months in, she tells me that she wears glasses, and she’s been wearing contact lenses all this time. She needs help seeing. I was like, listen, I’m not into all that Western medicine shit. If you want to see, then work at it. Figure out how not to be so myopic. You know?"
Maria Bamford (via unknownvariables)
Mr. Therapy Makes You Weak. Mr. Get Over It. Mr. I Don’t Get Why You’re Crying Can’t You Just Stop?
(via peacehon)
(via adultsupervisionpls)
