shichahn: (Feets!)
So, as most of you probably know, one of the latest advances in dinosaur reconstruction is identifying their coloration. We can do this by looking at the microscopic structures in dinosaur feathers, called melanosomes, in which certain melanosome shapes yield specific colors in the resulting feather. Previously, we had identified the colors of three dinosaurs: Sinosauropteryx, Anchiornis, and Archaeopteryx.

The latest addition is the coloration of Microraptor gui, which struck paleontologists as particularly remarkable when it was discovered - this dinosaur has four wings, rather than two. The front limbs as well as the back limbs are winged, giving it an unusual, biplane-like appearance. It is suspected that the surface area added by the lower/rear wings aided this animal in gliding from branches, rather than being used for powered, flapping flight like in modern birds.

But there's something else we should take from this image, the latest artistic rendering of Microraptor, as released yesterday by the American Museum of Natural History: the line between dinosaur and bird gets ever-fuzzier with each new discovery.



Microraptor had iridescent black plumage like Archaeopteryx, and like modern crows and blackbirds. That particular plumage coloration is usually for feather strength. Black feathers are more resistant to sun wear than other colors, so for birds that spend a lot of time in edge or open habitats, this is important for keeping feathers in good condition. Learning the coloration of Microraptor tells us that this dinosaur lived in relatively open areas, while its gliding style suggests that there was some kind of structure in those habitats as well - so a wooded edge, perhaps, or shrubland, or even the forest canopy, might have been where Microraptor lived. Its size - about that of a pigeon - and sharp teeth and talons suggest that it ate small vertebrate prey, and some Microraptor skeletons have small mammal and dinosaur/bird bones in the stomach. Around 300 fossils of this animal have been found, which is a rather incredible number. It was likely very common in ancient China, which makes it again very similar to today's blackbirds. Each little piece of information informs us further about its lifestyle - remarkable for something that has been extinct for nearly 120 million years.

I keep looking at that picture, above. And I want to show it to anyone who still believes that birds are not dinosaurs. Not that dinosaurs and birds are related, no - because that is a fairly well-established scientific fact by now, and anyone who still supports the ancestral archosaur hypothesis probably lives under a rock. But beyond that, birds are dinosaurs. If we can look at the skeleton of a Microraptor, or an Anchiornis or even a Sinosauropteryx and call it a dinosaur, and then look at the skeleton of a chicken or a hawk or an ostrich, the only thing that separates these animals is time. Yes, birds today are toothless, and many of them have strong flight muscles. But we have found toothless, beaked dinosaurs. Not the plant-eating kind, but the carnivorous birdlike Limusaurus. We also have a number of modern birds without strong flight muscles - think kiwis, cassowaries, emus, ostriches, and many others. So that does not separate birds and dinosaurs either. Birds are part of a long, continuous line of theropod dinosaurs which survived the mass extinction at the K-T boundary. They have evolved and rapidly diversified since then, but that does not make them not dinosaurs. It makes them survivors.
shichahn: (Feets!)
Delicious meal of the day: roast rabbit with coffee-chipotle rub (plus the usual roasting goods of potatoes, carrots, and garlic cloves). I really think rabbit is one of the best meats available. Thanks, Pele!

I have just returned from a 4-day trip to the SE Partners in Flight conference, where recent research on birds is presented every year. This year it was held in Raleigh, NC, included some excellent talks, and a poster session which took place at the NC Museum of Natural Science. My favorite quotation, from a presentation on controlling feral cats: "Cats are very popular. In fact, 87% of the internet consists of cats*. The rest is porn."

We also got to see NC State University's research forest, a restored prairie owned by the museum, and watch a displaying male woodcock on one very chilly evening, after which we retreated to Dos Taquitos, which is hands down one of the best Mexican restaurants I have ever been to. If you ever get the opportunity to try Chiles en Nogada, do it. Roast poblano, stuffed with shredded pork, apples, currants, and who knows what else, topped with a walnut cream sauce and pomegranate seeds. It's a traditional Mexican Independence Day dish due to its lovely green, white, and red colors, and is oh so amazingly good.

I talk about food a lot, don't I?

*Link not part of the original talk. But it proves his point.
shichahn: (Default)
Happy Birthday Mr. Hawking ♥

Also you guys, I totally forgot to mention it, but last Thursday was National Bird Day. I hope you appreciated some birds! I know I did. Pele did too because she caught and ate two in under 20 minutes. New record! (Speaking of "hawking"? lol)
shichahn: ([DW] dalek love)
So, in between bouts of working on a paper about shorebird habitat partitioning, I've also been finding some pretty cool things on the internet today. Coolest of all was finding this amazing piece on Reddit: I am Neil deGrasse Tyson -- AMA, in which Tyson, who, unsurprisingly, is a Redditor, sat and answered questions on all kinds of things. He really is a remarkable person, and his thoughts on everything from physics to education to life in general are absolutely worth reading by anyone and everyone. For those who don't know, Tyson is the director of the Hayden Planetarium at the American Museum of Natural History, and an example of my favorite kind of scientist - one who is not only a creative, thoughtful researcher, but who is also extremely good at making science accessible to anyone. So, go on, read what he has to say in the link above.

And then watch this video: Onward To The Edge, a music video about the wonders of space exploration. And then go watch all the other Symphony of Science videos. Look everyone, there is a valuable use for autotune after all!
shichahn: ([DW] dalek love)
So, in between bouts of working on a paper about shorebird habitat partitioning, I've also been finding some pretty cool things on the internet today. Coolest of all was finding this amazing piece on Reddit: I am Neil deGrasse Tyson -- AMA, in which Tyson, who, unsurprisingly, is a Redditor, sat and answered questions on all kinds of things. He really is a remarkable person, and his thoughts on everything from physics to education to life in general are absolutely worth reading by anyone and everyone. For those who don't know, Tyson is the director of the Hayden Planetarium at the American Museum of Natural History, and an example of my favorite kind of scientist - one who is not only a creative, thoughtful researcher, but who is also extremely good at making science accessible to anyone. So, go on, read what he has to say in the link above.

And then watch this video: Onward To The Edge, a music video about the wonders of space exploration. And then go watch all the other Symphony of Science videos. Look everyone, there is a valuable use for autotune after all!
shichahn: (Default)
So, every year, Scientific American magazine collects the best pieces of scientific writing found on blogs throughout the internet into a book, called The Open Laboratory. I only just learned about this as one of my favorite bloggers, biology professor PZ Meyers at the University of Minnesota, had one of his pieces nominated this year for addition to the book. Go to the above link to read his full explanation for the piece, if you like. Or if not, just read his letter to a nine year old girl who has so much to learn about how amazing our world truly is.

"Dear Emma;

I read your account of seeing a 3.75 billion year old moon rock, and how you asked the person displaying it "Were you there?", the question that Ken Ham taught you to ask scientists. I'm glad you were asking questions — that's what scientists are supposed to do — but I have to explain to you that that wasn't a very good question, and that Ken Ham is a poor teacher. There are better questions you could have asked.

One serious problem with the "Were you there?" question is that it is not very sincere. You knew the answer already! You knew that woman had not been to the moon, and you definitely knew that she had not been around to see the rock forming 3.75 billion years ago. You knew the only answer she could give was "no," which is not very informative.

Another problem is that if we can only trust what we have seen with our own two eyes in our short lives, then there's very little we can know at all. You probably know that there are penguins in Antarctica, and that the Civil War was fought in the 1860s, and that there are fish swimming deep in the ocean, and you also believe that Jesus was crucified two thousand years ago, but if I asked you "Were you there?" about each of those facts, you'd also have to answer "no" to each one. Does that mean they are all false?

Of course not. You know those things because you have other kinds of evidence. There are photographs and movies of penguins and fish, there are documents from the time of the Civil War, as well as the fact that in many places you can still find old bullets and cannon balls buried in the ground from the time of the war, and you have a book, the Bible, that tells stories about Jesus. You have evidence other than that you personally witnessed something.

This is important because we live in a big ol' beautiful world, far older than your 9 years, and there's so much to learn about it — far more than you'll ever be able to see for yourself. There's a gigantic universe beyond South Carolina, and while you probably won't ever visit a distant star or go inside a cell, there are instruments we can use to see farther and deeper than your eyes can go, and there are books that describe all kinds of wonders. Don't close yourself off to them simply because you weren't there.

I'd like to teach you a different easy question, one that is far, far more useful than Ken Ham's silly "Were you there?" The question you can always ask is, "How do you know that?"

Right away, you should be able to see the difference. You already knew the answer to the "Were you there?" question, but you don't know the answer to the "How do you know that?" question. That means the person answering it will tell you something you don't know, and you will learn something new. And that is the coolest thing ever.

You could have asked the lady at the exhibit, "How do you know that moon rock is 3.75 billion years old?", and she would have explained it to you. Maybe you would disagree with her; maybe you'd think there's a better answer; maybe you'd still want to believe Ken Ham, who is not a scientist; but the important thing is that you'd have learned why she thought the rock was that old, and why scientists have said that it is that old, and how they worked out the age, even if they weren't there. And you'd be a little bit more knowledgeable today.

I'll assume you're actually interested in knowing how they figured out the age of the rock, so I'll try to explain it to you.

The technique scientists use is called radiometric dating. It uses the fact that some radioactive elements slowly fall apart, turning into other elements. For instance, a radioactive isotope of potassium will decay over time into an isotope of another element, argon.

One way to think of it is that it's like an hourglass. You know how they work: you start with all the sand in the top half of the hourglass, and it slowly trickles into the bottom half. If you see an hourglass with all the sand at the top and none at the bottom, you know it was recently flipped over. If you see one with half the sand in the top, and half in the bottom, you know it's about halfway through the time it will run. And if you look at how quickly the sand moves through the neck of the hourglass, you could even figure out how long until it all runs out.

In radiometric dating, the scientists are looking at how far along all the radioactive potassium is in the process of turning into argon. The amount of potassium is like the amount of sand in the top half of the hourglass, while the amount of argon is like the amount in the bottom half. By measuring the relative amounts of the two elements, and by measuring how fast radioactive potassium turns into argon, we can figure out how long it's been since the rock solidified.

It takes a very long time for the decay to occur. It takes 1 and a quarter billion years for half the potassium to turn into argon. When they measured those elements in the moon rocks, they found that the radiometric hourglass had mostly run out, so they knew that it was very, very old.

Scientists double-check everything. They also looked at other elements, like how quickly uranium turns into lead, or rubidium into strontium, and they all agree on the date, even though these are decay processes that run at different rates. All the radiometric hourglasses they've used give the same answer: 3.75 billion years. None of them say 6,000 years.

I think you're off to a great start — being brave enough to ask older people to explain themselves is exactly what you need to do to learn more and more, and open up the whole new exciting world of science for yourself. But that means you have to ask good questions to get good answers so that you will learn more.

Don't use Ken Ham's bad question, and most importantly, don't pay attention to Ken Ham's bad answers. There's a wealth of wonderful truths that reveal so much more about our universe out there, and you do not want to close your eyes to them. Maybe someday you could be a woman who does go to the moon and sees the rocks there, or a geologist who sees how rocks erode and form here on earth, or the biologist who observes life in exotic parts of the world…but you won't achieve any of those things if you limit your mind to the dogma of Answers in Genesis.

Best wishes for future learning,

PZ Meyers."

-from Pharyngula.
shichahn: (Default)
So, every year, Scientific American magazine collects the best pieces of scientific writing found on blogs throughout the internet into a book, called The Open Laboratory. I only just learned about this as one of my favorite bloggers, biology professor PZ Meyers at the University of Minnesota, had one of his pieces nominated this year for addition to the book. Go to the above link to read his full explanation for the piece, if you like. Or if not, just read his letter to a nine year old girl who has so much to learn about how amazing our world truly is.

"Dear Emma;

I read your account of seeing a 3.75 billion year old moon rock, and how you asked the person displaying it "Were you there?", the question that Ken Ham taught you to ask scientists. I'm glad you were asking questions — that's what scientists are supposed to do — but I have to explain to you that that wasn't a very good question, and that Ken Ham is a poor teacher. There are better questions you could have asked.

One serious problem with the "Were you there?" question is that it is not very sincere. You knew the answer already! You knew that woman had not been to the moon, and you definitely knew that she had not been around to see the rock forming 3.75 billion years ago. You knew the only answer she could give was "no," which is not very informative.

Another problem is that if we can only trust what we have seen with our own two eyes in our short lives, then there's very little we can know at all. You probably know that there are penguins in Antarctica, and that the Civil War was fought in the 1860s, and that there are fish swimming deep in the ocean, and you also believe that Jesus was crucified two thousand years ago, but if I asked you "Were you there?" about each of those facts, you'd also have to answer "no" to each one. Does that mean they are all false?

Of course not. You know those things because you have other kinds of evidence. There are photographs and movies of penguins and fish, there are documents from the time of the Civil War, as well as the fact that in many places you can still find old bullets and cannon balls buried in the ground from the time of the war, and you have a book, the Bible, that tells stories about Jesus. You have evidence other than that you personally witnessed something.

This is important because we live in a big ol' beautiful world, far older than your 9 years, and there's so much to learn about it — far more than you'll ever be able to see for yourself. There's a gigantic universe beyond South Carolina, and while you probably won't ever visit a distant star or go inside a cell, there are instruments we can use to see farther and deeper than your eyes can go, and there are books that describe all kinds of wonders. Don't close yourself off to them simply because you weren't there.

I'd like to teach you a different easy question, one that is far, far more useful than Ken Ham's silly "Were you there?" The question you can always ask is, "How do you know that?"

Right away, you should be able to see the difference. You already knew the answer to the "Were you there?" question, but you don't know the answer to the "How do you know that?" question. That means the person answering it will tell you something you don't know, and you will learn something new. And that is the coolest thing ever.

You could have asked the lady at the exhibit, "How do you know that moon rock is 3.75 billion years old?", and she would have explained it to you. Maybe you would disagree with her; maybe you'd think there's a better answer; maybe you'd still want to believe Ken Ham, who is not a scientist; but the important thing is that you'd have learned why she thought the rock was that old, and why scientists have said that it is that old, and how they worked out the age, even if they weren't there. And you'd be a little bit more knowledgeable today.

I'll assume you're actually interested in knowing how they figured out the age of the rock, so I'll try to explain it to you.

The technique scientists use is called radiometric dating. It uses the fact that some radioactive elements slowly fall apart, turning into other elements. For instance, a radioactive isotope of potassium will decay over time into an isotope of another element, argon.

One way to think of it is that it's like an hourglass. You know how they work: you start with all the sand in the top half of the hourglass, and it slowly trickles into the bottom half. If you see an hourglass with all the sand at the top and none at the bottom, you know it was recently flipped over. If you see one with half the sand in the top, and half in the bottom, you know it's about halfway through the time it will run. And if you look at how quickly the sand moves through the neck of the hourglass, you could even figure out how long until it all runs out.

In radiometric dating, the scientists are looking at how far along all the radioactive potassium is in the process of turning into argon. The amount of potassium is like the amount of sand in the top half of the hourglass, while the amount of argon is like the amount in the bottom half. By measuring the relative amounts of the two elements, and by measuring how fast radioactive potassium turns into argon, we can figure out how long it's been since the rock solidified.

It takes a very long time for the decay to occur. It takes 1 and a quarter billion years for half the potassium to turn into argon. When they measured those elements in the moon rocks, they found that the radiometric hourglass had mostly run out, so they knew that it was very, very old.

Scientists double-check everything. They also looked at other elements, like how quickly uranium turns into lead, or rubidium into strontium, and they all agree on the date, even though these are decay processes that run at different rates. All the radiometric hourglasses they've used give the same answer: 3.75 billion years. None of them say 6,000 years.

I think you're off to a great start — being brave enough to ask older people to explain themselves is exactly what you need to do to learn more and more, and open up the whole new exciting world of science for yourself. But that means you have to ask good questions to get good answers so that you will learn more.

Don't use Ken Ham's bad question, and most importantly, don't pay attention to Ken Ham's bad answers. There's a wealth of wonderful truths that reveal so much more about our universe out there, and you do not want to close your eyes to them. Maybe someday you could be a woman who does go to the moon and sees the rocks there, or a geologist who sees how rocks erode and form here on earth, or the biologist who observes life in exotic parts of the world…but you won't achieve any of those things if you limit your mind to the dogma of Answers in Genesis.

Best wishes for future learning,

PZ Meyers."

-from Pharyngula.

Profile

shichahn: (Default)
shichahn

May 2014

S M T W T F S
    123
4567 8 9 10
11121314151617
18192021222324
25262728293031

Syndicate

RSS Atom

Most Popular Tags

Style Credit

Expand Cut Tags

No cut tags
Page generated 21 Sep 2017 08:32
Powered by Dreamwidth Studios