Posts from the ‘link’ Category

521 Years

Link: 521 Years

jtotheizzoe:

That’s the half-life of DNA, according to new research from scientists in Denmark and Australia. That means that dinosaur DNA is pretty much out of the question, but that the Earth’s primary genetic material lasts longer than once thought.

By studying DNA left over in leg bones of extinct moa birds of different ages, they were able to determine how fast it naturally degrades. Water, essential for life, can be pretty reactive over the span of hundreds and thousands of years, slowly breaking the bonds that hold DNA molecules together.

If half the DNA is gone in 521 years, then even at optimal temperatures any sample would be almost totally degraded after 6.8 million years.

I guess there’s a few questions that remain, like if different environments could lead to different numbers, or what different soils could do to move that number up or down … but I’d sell your stock in any Jurassic Park-type ventures.

More at Nature.

Well that’s a bummer. Guess we’ll just have to build our own dinosaurs from scratch!

(Don’t hold your breath; we can barely make single living cells.) 

How Science Explains America’s Great Moral Divide

Link: How Science Explains America’s Great Moral Divide

jtotheizzoe:

From a longer interview at Scientific American, Jonathan Haidt offers this explanation of how modern human culture, especially American moral/political culture, is the result of our unique evolutionary path, part bee and part primate:

For the last half of the 20th century, the dominant idea in the social sciences was that people are selfish. Economists thought that people were only out to maximize their self-interest, political scientists believed that people voted entirely for their self-interest, and biologists told us that we were driven by selfish genes, which make us generous only when it will help our kin or our reputations. Self interest is of course a very powerful force, yet it leaves out our deep and passionate desires to be part of a group, to lose ourselves in something larger than ourselves. It leaves out so much of the psychology of religion and self-transcendence.
This is why I say that one of the basic principles of moral psychology is that we are 90 percent chimp and 10 percent bee. Most of our social nature is like that of other primates – we’re mostly out for ourselves. But because our evolution was shaped by a few hundred thousand years of intense group versus group conflict, we are also very groupish. We are descended from groups that had fine-tuned mental mechanisms and cultural rituals for binding themselves together into communities able to work together, suppress free riders, and achieve common ends. When we do these things we are more analogous to bees than to chimps. But for us, it’s just temporary. We have brief collective moments, and we can do great things together in those moments, but eventually, self-interest returns.

A fine explanation of that conflict that seems to be at the heart of so much political tension: Is this about me, or about us?

Agree?

The food-chain effects of invasive species

Link: The food-chain effects of invasive species

A study tried to determine the effect that losing apex bird species in a large-scale environment would have, and to do so turned its eyes on Guam.

There, brown snakes were introduced by trade years ago. On the small island, insectivorous birds were the apex predators until the snakes were introduced, and have been almost entirely wiped them out. 

The study found that during the wet season, Guam’s spider web density was almost 40 times as high as nearby islands with healthy bird populations. During the dry season, that number dropped to 2.3 times as high. 

Another example of how dangerous a relatively benign non-native species may be to an environment, and the top-down effects they can have on the food chain.

Help map seafloors and sealife in this dynamic project

Link: Help map seafloors and sealife in this dynamic project

Help scientists identify seafloor types and living species in this engaging, citizen dependent project. The hope is to identify species, map populations, and get a better idea of the makeup of the northeastern continental shelf of the U.S. 

Despite just being released, over 200,000 images have been mapped and possibly even a new species. How reliable those mappings are remains to be seen, but with such a great amount of input the results should even out.

A fantastic project that really takes advantage of the huge citizen workforce that is available on the web. I’m looking forward to see what results Seafloor Explorer can give us, and whether any similar projects pop up.

Only passionately curious: Bill Nye the Science Guy

Link: Only passionately curious: Bill Nye the Science Guy

astrotastic:

bvix:

-Season 1

1. Flight

2. The Earth’s Crust
3. Dinosaurs
4. Skin

5. Buoyancy

6. Gravity

7. Digestion

8. Phases of Matter

9. Biodiversity

10. Simple Machines

11. The Moon

12. Sound

13. Garbage

14. Structures

15….

There’s really no really to attend college classes now that you have all of these.

But not really. Go to class.

NPR Fresh Air: To this day, they are the most efficient insulation known. We haven’t…

Link: NPR Fresh Air: To this day, they are the most efficient insulation known. We haven’t…

nprfreshair:

To this day, they are the most efficient insulation known. We haven’t been able to match them with synthetics, and I think it boils down to that growth process and the fact that you can make these fine, fine branching structures. The key to insulation is what they call loft — how much air…

Nicholas Eftimiades doing a Reddit AMA

Link: Nicholas Eftimiades doing a Reddit AMA

Go ahead and click the link, Eftimiades lets you know who he is right off the bat. He’s in a pretty unique position to answer some cool future-tech questions and has some really fascinating responses on world politics and such.

Not getting quite the response Obama’s AMA did, but Eftimiades is answering more and the website can handle it.

Paleo-politics: The really long view

Link: Paleo-politics: The really long view

From The Maddow Blog:

Doing some research recently on African-American voting patterns, I came upon this map of American ancestry from the U.S. Census (pdf):

And it reminded me of a mindblower of a political explanation that I meant to share here.

This is long, so meet me after the jump…

Looking at the map above, you notice the swath of African-Americans (purple) running through the southeast. Something I hadn’t heard of but is apparently relatively common knowledge is that that pattern in the population is referred to as the Black Belt.

That may seem a little coarse, but it actually refers to the color and richness of the soil.

I looked for maps of soil color, but if such a thing exists, I wasn’t able to find it. The clearest picture of soil distribution matching that pattern was this map of “soil orders“ suggesting ultisols and/or vertisols having something to do with that color:

This National Science Foundation lesson on soil orders offers a more detailed version and settles the question.

Vertisols are definitely black. (pdf) (Ultisols, not so much (pdf).)

Our friend, the google, shows how that pattern manifests today in the form of farms making use of that rich soil that comprise that lighter colored swirl.


View Larger Map

Farms are actually the point, because while Black Belt may have been a reference to black soil, that’s not to say the Black Belt doesn’t also have racial meaning. Pretty much every source one checks cites this explanation from Booker T. Washington’s 1901 autobiography Up From Slavery:

…The term was first used to designate a part of the country which was distinguished by the color of the soil. The part of the country possessing this thick, dark, and naturally rich soil was, of course, the part of the South where the slaves were most profitable, and consequently they were taken there in the largest numbers. Later and especially since the war, the term seems to be used wholly in a political sense—that is, to designate the counties where the black people outnumber the white.

That “political sense” Washington refers to includes an electoral sense as well. Slave-descendant voters in Black Belt counties leave a blue Democratic voting stripe through otherwise red states, seen especially vividly in this New York Times county map of the 2008 election results:

I also ran into this voting pattern described as “the cotton vote.” As data became available from the 2008 election, aligning a map of the blue strip of Obama-voting Black Belt counties with a map of cottom production from 1860 (!) revealed a remarkable correlation:

I already think that’s mindblowing, but that’s not even the mindblowing part. The mindblowing thing is that what’s really responsible for this phenomenon of modern politics is the still-forming North American coastline of 100 million years ago.

From Deep Sea News earlier this summer:

“During the Cretaceous, 139-65 million years ago, shallow seas covered much of the southern United States. These tropical waters were productive–giving rise to tiny marine plankton with carbonate skeletons which overtime accumulated into massive chalk formations. The chalk, both alkaline and porous, lead to fertile and well-drained soils in a band, mirroring that ancient coastline and stretching across the now much drier South. This arc of rich and dark soils in Alabama has long been known as the Black Belt.”

Behold! Your late Cretaceous coastline and future Democratic strongholds:

Oh, what? You’ve still got some unblown mind left? I have a little more.

The map above represents 75 million years ago. Dr. Ron Blakey of Northern Arizona University actually offers us several maps in the late Cretaceous range. But why would that time period be particularly relevant? I find two explanations. One is that the Cretaceous was a boom time for the sort of plankton that would eventually become the Black Belt. 

The other explanation is that the Cretaceous ended when, 65 million years ago, an asteroid (or asteroids) slammed into the earth, right across the future-Gulf of Mexico at the tip of the Yucatan Peninsula. Not only did the impact and resulting fallout from that asteroid kill the dinosaurs, it also wiped out huge quantities of marine life, including many of the “tiny marine plankton with carbonate skeletons” (I’m guessing some version of Coccolithophore? Anyone?) that would become the rich soil that slaves would farm on land their ancestors would inhabit in voting districts that would favor Democratic candidates around the turn of the second millennium of the Common Era.

Below is a map of the Chicxulub Crater, the crater left by the asteroid 65 million years ago, showing its location at the end of the Yucatan Peninsula. It looks like a topographical map, but actually it’s a Bouguer gravity anomaly map. The best explanation I could find for gravity anomaly maps is from this Earth Observatory page from NASA.

I think the idea is that the impact created ridges of higher density, which show up as gravity anomalies. As ever, any insights and expertise you can offer on anything in this post is greatly appreciated.

Also, the more I researched this, the more I ran into people who’d already done portions or variations of it. I tried to include as many links as I could to previous work. Credit also to Allen Gathman for the cotton vote connection.

Article By Will Femia

This has to be one of my favorite posts in a long time. It encompasses such a variety of fields, from politics to history to several fields of science. All of them interesting, and each important as much individually as to the whole. A bit of a long post, but every bit of it interesting and well worth the read! 

Stem Cell Basics

Link: Stem Cell Basics

ohyeahdevelopmentalbiology:

This primer on stem cells is intended for anyone who wishes to learn more about the biological properties of stem cells, the important questions about stem cells that are the focus of scientific research, and the potential use of stem cells in research and in treating disease. The primer includes information about stem cells derived from embryonic and non-embryonic tissues. Much of the information included here is about stem cells derived from human tissues, but some studies of animal-derived stem cells are also described.

The NIH developed this primer to help readers understand the answers to questions such as:

  • What are stem cells?
  • What are the different types of stem cells, and where do they come from?
  • What is the potential for new medical treatments using stem cells?
  • What research is needed to make such treatments a reality?

A nice introduction to stem cells. 

Not only are stem cells awesome, but they’re always on the peripheral of political debate. Should it come up again, you should be well acquainted with them so you can stand on the right side..the side of science.

Butterflies around Fukushima reveal high level of mutation

Link: Butterflies around Fukushima reveal high level of mutation