Once again, biology dominates and we have another article about CRISPR so let’s start with that.
- I can’t see how this can be much of a surprise, but as this article states, it has been found that usage of the CRISPR-Cas9 gene editing technique can cause hundreds of unintended mutations. This is based on an experiment in which the whole genome of mice that had undergone editing with the mice were sequenced to look for all mutations as opposed to looking merely at sites which the researchers were attempting to change. So far they haven’t noticed anything obviously wrong with the animals in question but it’s clear that scientists must be aware of unintentional side effects when they employ technique.
- Next up is a very impressive experiment in which scientists showed some monkeys photographs of human faces and then recreated those photographs from recordings to the monkeys’ brain ways. In effect, they were able to read the brains of the monkeys, or at least that specific part of their brains responsible for recognizing faces, the so-called face patch regions. Apparently sampling electrical readings of around 100 neurons from the face patch regions was sufficient to recreate images that are eerily close to the photographs of the faces that the monkeys saw.
- One of two articles this month from The Economist, the only publication I subscribe to, is about a potential new treatment for autism. It’s been tested on both mice and people and it’s a treatment, not a cure, as when its effects leave the body, previous behaviors return but the improvement seems astounding. Strangely enough the medicine was actually discovered in 1916 as a treatment for the sleeping sickness spread by tsetse flies.
- Usually when I link content from The Economist for this regular feature, it’s from their science and technology section but this one is from their weekly column on language. It talks about the common perception that women talk more than men and cites an experiment which monitored participants in their daily to record how many words they spoke. The results were that on average men and women spoke about the same number of words per day but that audiences tend to report that women speak more even when both are reading the exact same script.
- Finally, here’s a fascinating article about the domestication of cats. It claims that cats, unlike pretty much every other animal reared by humans, have never been properly domesticated. Based on analysis of cat mitochondrial DNA, humans began breeding cats only around the Middle Ages. This explains why cats don’t share the typical signs of animal domestication that we see in other species such as the infantilization of facial features. However it does note that we are currently in the initial stages of domesticating cats, suggesting that a few thousand years from now, cats may exhibit dog-like traits and behaviors.
All of the interesting stuff this month are in biology and medicine. This has been the trend for a few months now I guess.
- The first link goes to a series of photos that I won’t reproduce here so you’ll just have to click that. It’s about the discovery of a petrified dinosaur fossil of a type of ankylosaur. The reason this is so amazing is that instead of pieces of bones or teeth, this particular specimen includes a substantial portion of its armor so that for the first time scientists don’t have to infer what the exterior of the dinosaur looked like from its bone structure but can just see it for themselves. The photos are truly breathtaking.
- Next we have a discovery that has the potential to rewrite all the textbooks about the origin of humans but is probably misguided. For a long time now, the consensus that our species originated in Africa but a group of scientists now claim that the discovery of two fossils of an ape-like creature in Bulgaria and Greece is evidence that our ancestors appeared in Europe instead. They date the fossils as some 7.2 million years old, older than oldest evidence of African hominids. Still, others are skeptical as consensus is fairly solid and claim instead that these fossils are those of some other ape-species who are not the ancestors of humanity. You can read some of those arguments here.
- Then we have this article about how insect populations all over the world seem to be dropping propitiously. This is based on automatic sensors of various kinds at various sites. In Germany for example, one group reported that counts at insect trapping sites have fallen by 80% between 1989 and 2013. The reasons for the phenomenon are unknown and guesses include pesticides and changes in land use but these are huge changes that have important knock on effects throughout the entire food chain.
- AIDS patients have been able to get the disease under control for a while now but a permanent cure still seems impossible. This article however talks about effecting just such a cure by using the CRISPR/Cas9 gene editing tool to excise HIV DNA from infected issues. Intriguingly the team did so not only with mice infected with mouse equivalent of human HIV-1 but also with mice engrafted with human immune cells that have been infected with human HIV-1. I know that when I first posted about CRISPR/Cas9 I said it would be immensely useful but I’m still surprised by how quickly new uses for it are cropping up all over the place.
- I normally focus on basic research and ignore cool new devices but this bit about the Apple Watch caught my attention. I’m skeptical of claims about such devices for medical uses but this article claims that it does indeed work. This device comes with a heart rate sensor and a long study has now concluded that it is able to detect atrial fibrillation, an abnormal heart rate that can lead to stroke or heart disease, 97 percent of the time. This uses special software that isn’t yet available to ordinary users but it does prove that such devices have lots of real potential.
A whole bunch of stuff this month, most of it once again in biology.
- Let’s start with the many articles about animals this month. I’ve previously posted about how octopuses are highly unusual in that much of their nervous system is distributed along their tentacles, unlike other animals in which their neurons are mostly located in their brains. This article talks about how they are also highly weird in that they make extensive use of RNA editing. This seems to allow them to tailor make proteins for a variety of different situations but the researchers speculate that this comes at a cost of slower long-term evolution.
- Next up is a short article with a cool video that demonstrates how an African ant species that eats only termites has an unusual survival strategy: they are able to sense when their compatriots become injured and come to their aid by carrying them back to the nest to recuperate. Or as the article puts it, they employ combat medics. As far as I know, ants don’t have mechanisms to allow them to heal major injuries or regenerate lost limbs but the articles that they may in time learn to adapt to the loss.
- Having been laid low by the flu for much of this month, I was pleased to see this article. Viruses are of course unaffected by antibiotics which is why the usual medical advice for dealing with the flu is just to wait for your own immune system to develop antibodies to overwhelm it. This article talks about how a species of frogs in India oozes mucus that is able to latch onto flu virus particles and cause them to burst apart. Perhaps even more unusual is that it specifically targets only flu virus particles, in fact only the H1 subtype of flu viruses, and nothing else so it appears to be non-toxic.
- The last of the articles about animals is this one about the invention of an artificial womb. Hitherto all reproductive technologies such as artificial insemination or cloning still rely on a live mother to carry the fetus to term. This invention, called the Biobag, resembles a clear plastic bag that allows the fetus to develop inside it immersed in an electrolyte solution and equipped with pumps to circulate its blood. So far it has only been tested with baby sheep but if it works as promised, it will obviously be extended to all kinds of animals.
- Finally let’s end with a history article which proposes a different view of the practice of footbinding in China. The usual view is that it is imposed on women who are trophy wives as a visible symbol of their inability to work and therefore are dependent on servants for their wellbeing. This article argues that they do indeed valuable work with their hands, mainly weaving cloth, and that footbinding was a way to ensure that they stuck to it. They offer as proof the fact that the practice was common even among poor people and that its demise can be tracked by the arrival of machine-made cloth. I have no idea how true this alternative view is, but it certainly makes for fascinating reading.
I haven’t updated my blog in a few days due to travel but I’m back just in time for this monthly feature. Just four of them this month and they’re all about biology.
- First up, here’s this bit about the first known use of gene therapy to cure a patient of sickle cell anemia. The doctors harvested stem cells from the patient’s bone marrow, altered the DNA so that they would produce normal hemoglobin, used chemotherapy to kill off the remaining stem cells and then inserted the new ones. This makes it a case of genetic engineering on a human patient in vivo, instead of altering an embryo so that it would develop differently.
- This next article is also about DNA engineering. In this case, scientists have created wholly artificial chromosomes for yeast cells. The chromosomes are not only synthetic but edited to remove what is believed to be rubbish code in the original DNA and to alter the code’s punctuation to eliminate one letter from the usual stop code. The hope is that the yeast cells can still live normally after these modifications and the freed letters can open up more space for more extensive changes in the future.
- Dinosaur aficionados were up in arms earlier this month as a new paper proposes a radical redrawing of the family tree. Historically, dinosaurs have been classified according to whether they are “bird-hipped” or “reptile-hipped”. But as more data has been gathered, this classification system has become ridden with inconsistencies so a new paper now proposes that it be thrown away entirely. It may not seem like much to many people but it does matter to children who grew up memorizing names of their favorite dinosaurs and some of them may no longer be properly recognized as being dinosaurs at all!
- Finally here’s a cool bit about a couple of researchers who tried to put hard numbers on how many spiders there are around the world and how much they eat. They conclude that there are around 25 million tonnes of spiders on Earth, a number that is hard to put in context. But a more comprehensible figure is the 400 million tonnes of other animals that they consume a year because that is also the approximate mass of the total number of human beings living on the planet.
A solid selection of articles this time around, with findings that are a lot more significant than the boring stuff last month.
- Let’s just get NASA’s huge announcement out of the way first. As I’m sure all of you have heard by now, this is the discovery of a system that contains at least seven planets that are approximately the same size as our Earth orbiting around a single star. The system is less than 40 light years away from us and the planets seem to be packed in an astonishingly small volume of space, which makes it appropriate that it’s being called TRAPPIST-1 although it really refers to the telescope that found the system. Obviously we still know very little about them but the most exciting thing that we do know is that since they’re packed so close together, it should be possible to view the other planets if you’re on the surface of one of them. Their skies must have an amazing view.
- Moving on to animal behavior, this study talks about how monkeys and dogs can engage in social evaluations as humans do. The animals were allowed to observe humans interacting with each other, specifically a human actor making a request of another and the other one either cooperating or refusing. The scientists found that when the second person helped, they were equally likely to accept food from either person. But when the other person refused, the animal was more likely to accept food from the first person.
- Next are the workings in human society and I was fascinated to read this study about school voucher programs in the United States. It finds that a lot of this funding has gone on to schools that are affiliated with religions but instead of making the education more religious it seems to have made the schools more secular instead as they strive to welcome more students. Combined with the drop in attendance of church services as seen everywhere, the funding seems to also be displacing traditional tithes as a major source of funding for churches.
- Then there’s this study which tries to explain the unusually high life expectancy of Israeli men by linking it to obligatory military service. Apparently Israeli men live for around 7 years longer than men in other countries under similar conditions. The military service which is theorized to impose physical fitness on men doesn’t explain all of the additional lifespan but it does seem to explain about half of it.
- Finally here’s an article that is less about what was discovery than about how it was made. The finding is that about 2,500 years ago, the Earth’s magnetic field was briefly 2.5 times stronger than it is usually. It was possible to know this by studying ceramic pots that were made during that time. The dates on which they are made can be precisely dated because the bureaucracy of that era required that they carry administrative stamps. The clay used include ferromagnetic minerals that once fired and then cooled down, lock in information about the magnetic patterns at that time, allowing scientists to make inferences about the strength of the Earth’s magnetic field.
Like everyone else, my usual routines have been severely disrupted by the Chinese New Year holiday season. As far as I can tell, interesting science news is down this month as well as there are few really noteworthy announcements. The ones that I read this month probably belong more in the entertaining and sensational science news category.
- First, we have this bit about vampire bats in Brazil which ordinarily prey on birds having learned to drink blood from humans. This is significant as they have been previously been observed to starve rather than feed on pigs or goats and is probably an instance of natural selection in action as human encroachment in their habitat leads to a drop in the availability of their usual prey.
- Also in biology is the mystery of why so many corpse flowers bloomed in the year 2016. These plants bloom unpredictably once every 5 to 10 years and famously give off a smell of decomposing flesh when they do so. There aren’t many of these being cultivated yet somehow many of them bloomed in the same year all across the US and some other countries and botanists have no idea why this is so.
- Finally, here’s an announcement about a nova that should be visible to the naked eye on Earth. The problem is that it’s scheduled for 2022. The star in question is KIC9832227, actually a pair of stars that very close to one another. Astronomers have noted that the smaller of the two stars has been spiralling towards its companion and hence a nova is expected. This is noteworthy because all previous novas have been detected after the fact and this will be the first time that a nova has been predicted in advance.
Pulling the trigger on this one a little earlier than usual to square things with my posting schedule.
- The most headline grabbing announcement of the month is the news that more than 20 years after Jurassic Park, scientists have found a dinosaur tail preserved in amber. The incredible thing about this find that was made in Myanmar is that the tail is feathered and the features show up in wonderful detail, making it a powerful demonstration that dinosaurs really are feathered animals and not the scaly reptiles as envisioned in the film. Analysis indicates that this early form of feather isn’t well adapted for flight and so must have served some other function, regulating body temperature for example, so it’s also a good example of how features that evolved to serve some purpose went on to become adapted for another purpose.
- Biology is probably the theme of this post as the next entry is about elephants. One of the key differences between African and Asian elephants is that all male and female African elephant usually have tusks while only some male Asian elephants have tusks while some female ones have short tusks known as tushes. This article talks about how ivory poaching have caused an increasing number of African elephants to be born tuskless, a clear case of natural selection in action. In one national park, high levels of poaching have even caused 98 percent of female elephants to be born tuskless.
- Next up are horses. No new science here, just a bit of news about how Adolfo Cambioso, apparently the world’s best polo player, used a team of six horses in a high-profile event, all of which were clones of the same mare. I find it sobering how this passes without notice these days indicating that this is now a mature and commonly used technique.
- Still on the subject of animals, this article talks about how a Chinese team fed silkworms mulberry leaves that have been sprayed with a solution containing graphene. The silkworms then went on to produce silk that is twice as tough as normal silk. This seems a bit too easy. How could the researchers be sure that the graphene would be incorporated in silk? But it sure is cool if it’s true.
- Finally, here’s one that’s at least potentially about humans. It talks about disturbing your circadian rhythms can be a cause for liver cancer. The mechanics in mice stems from the fact that disrupted day-night cycles cause the animals to overproduce bile acid. Over time, this damages the liver and leads to cancer. They’re only guessing that the same applies to people and accordingly advise to follow a regular sleeping schedule.