Science News Roundup: 6/12/12

It’s been a fairly slow news week in science, but there are still a few fascinating stories to share with you. Researchers have made a potential breakthrough in fetal genetic testing, dinosaurs may not have been as big as we thought, and some birds have different personalities according to their coloring. Oh, and penguins are scandalously filthy sexual deviants. Yeah, I figured that would get your attention!

[dropcap4 bgColor=”#4f134d” textColor=”#ffffff”]A[/dropcap4]merican researchers have successfully sequenced the genome of an 18-week-old fetus using DNA samples from the mother and father. Fetal DNA was taken from the mother’s bloodstream and sequenced by comparing the fragments to the genome of each parent. When compared to actual fetal cells after birth, they discovered that the preliminary sequence was 98% accurate. When perfected, this could be a safer way to screen for genetic disorders, since amniocentesis carries a risk of miscarriage.

Tree of Life diagram
Tree of life with only about 10% of known species

The Open Tree of Life project is working to diagram the relationships between every known species in the world. This massive undertaking, made possible only by modern computing power, will analyze each species to figure out its closest relatives and evolutionary history, and will combine already-existing trees to complete one comprehensive diagram. As new species are discovered and described, scientists will be able to add them to the tree and make any needed adjustments to how others are related. The project will have several applications; from helping to understand past rapid periods of diversification or extinction to looking for medicines from closely related sources of existing drugs.

A dock ripped loose during last March’s tsunami in Japan made landfall on a beach in Oregon last week. The 66 foot long, 180+ ton dock will be difficult to remove, but volunteers are already at work cleaning it of biological hitchhikers, including an invasive species of seaweed, mussels, and barnacles that are foreign to those waters. Other debris, including a Harley-Davidson motorcycle, has already washed up on American and Canadian shores recently and much more is expected over the next few months.

Illustration of two Gouldian finches perched on a branch, one with a red head and the other with a black head
Pretty Birds! by Marc Athanase Parfait Å’illet Des Murs

Some finches have different personalities discernible by their head color. Most Gouldian finches have either red or black heads, though a few have yellow heads. In an experiment where food was put out such that only one bird could feed at a time, the red-headed finches were aggressive about making sure they got to eat first, while the black-headed ones were braver about returning to the food source after a simulated predator approach and were quicker to investigate new objects introduced by the scientists. Further research is needed to figure out why the different coloring is associated with different behavior. (As a fellow redhead who is very protective of her food, I am proud of my feathered friends!)

Dinosaurs may not have been as big as was previously estimated. Researchers developed a new method to measure the minimum amount of skin to cover an animal’s skeleton and then figured out how the actual volume compares. In all of the large land animals tested, they had a volume about 21% larger than the minimum. Applying this ratio to dinosaurs yielded numbers drastically lower than was previously thought. Brachiosaurs were thought to weigh up to 88 tons, but if these new measurements are accurate, they probably only weighed about 25 tons.

An undersea volcano off the coast of Oregon gave clear signs of an impending eruption in the months and hours leading up to its eruption in April of last year. Monitoring devices on Axial Seamount had shown seafloor swelling around it for years, but it had increased rapidly in the five months leading up to the eruption. There was a marked increase in seismic activity hours before the blast, and the seafloor abruptly jumped 2.75 inches within an hour of the eruption as the magma rose to the surface. While most undersea volcanoes aren’t as well monitored, it’s hoped that these observations can lead to better warning before future volcanic events.

Adelie penguin standing on ice

Penguins are apparently dirty sex fiends. A newly rediscovered century-old paper by George Murray Levick, a scientist who accompanied Scott on his 1910-13 expedition to Antarctica, details his horror at the “astonishing depravity” of Adélie penguins. He was so shocked by their behavior that he wrote his notes in Greek and censored all mentions of the perversions from the paper he published on his return. He did, however, write a short pamphlet called Sexual Habits of the Adélie Penguin which was only given to a handful of experts, and it was this pamphlet that was recently found after having been lost for decades. I can’t help but laugh at the thought of scientists passing around a secret treatise of penguin porn. If you want to read all about it, here you go (but be warned, some of the behaviors are potentially triggering, which is why I’m not describing them in further detail).

It looks like the speed of light is safe in its place as an unbreakable barrier. A few months ago some anomalous results at the Large Hadron Collider seemed to imply that certain neutrinos were zipping through the supercollider 60 nanoseconds faster than lightspeed, much to the excitement of the scientific community. However, experiments at other labs were unable to replicate the results, so it’s likely that the initial readings were due to a measurement error. It would have been awesome to learn that objects can move faster than light, but instead we got a demonstration of the scientific method. Still pretty cool.

By [E] Hillary

Hillary is a giant nerd and former Mathlete. She once read large swaths of "Why Evolution is True" and a geology book aloud to her infant daughter, in the hopes of a) instilling a love of science in her from a very young age and b) boring her to sleep. After escaping the wilds of Waco, Texas and spending the next decade in NYC, she currently lives in upstate New York, where she misses being able to get decent pizza and Chinese takeout delivered to her house. She lost on Jeopardy.

12 replies on “Science News Roundup: 6/12/12”

The full study is here. Basically, little bits of fetal DNA can be found in the mother’s bloodstream (damn, pregnancy is weird). By comparing the fragments to the parents DNA they can figure out which pieces came from which parent and where they go. It’s like trying to put together a jigsaw puzzle that has pieces from two different boxes and you don’t know quite what the finished product will look like, but you can guess based on where the pieces went on the originals. Except with millions of tiny pieces that occasionally change shape all on their own.

Ack, I don’t have access, and the genetics is probably beyond me anyway:) I’ll keep an eye on Ed Yong and see if he writes it up. I have many questions! Like: is it easier to do this when the fetus is male, as its DNA would be easier to distinguish from the mother’s based on the Y chromosome? Does the cost and complexity outweigh the benefit of standard screening for the big chromosomal disorders (trisomy 13, 18, 21)? How are they planning to get that false positive rate for de novo mutations down?

It would be a tiny bit easier for a male, but not much since it would only be a difference of one chromosome out of 46 total (23 pairs). Right now it’s waaaay too expensive and complicated and the error rate has to come down for it to be a viable alternative, but this was a first attempt and no one knew if it would work at all so it’s pretty exciting. It’ll probably take a few years to work out the kinks and in that time the cost will go down as computer processors speed up, so hopefully it’ll be available soon. (Assuming it doesn’t get banned because OMG some people might have abortions if they find out early that the fetus isn’t viable or the parents don’t have the resources/desire to raise a child with a serious genetic disorder.)

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