biology, evolution, Miscellaneous, Science, SF and science, Sunday Science Stories

Sunday Science 08/10/17

Welcome to today’s Sunday Science, with some weird and wonderful animals, some human quirks, and future life on the oceans..

How did the weevil get its shell? Well, they have bacterial symbionts who live inside them with severely reduced genomes. These bacteria do not much more than churn out the amino acid tyrosine, needed to harden the shells. I love how nature is so weird sometimes. Link is to the full scientific paper, so fairly technical.

A fascinating account of the changes in the onset and duration of puberty, which has changed significantly over the years.

Seasteading, which means living on permanent floating artificial habitats, outside the jurisdiction of any government, seems to be taking a step forward. This long thoughtful piece examines the progress and implications of what was, until now, an idea confined to science fiction and libertarian dreamers.

And finally…did you ever collect tadpoles as a child and try and grow them to frogs? Well, toad tadpoles are less cute than they look: they contain potent heart poisons. The researchers thought this was to ward off competition from frogs, but it seems actually to be do with each other – the more toad tadpoles there are, the more toxic they get.

Credit: This week’s featured image via Nature, by Bert Willaert/NPL.

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biology, Developmental biology, evolution, genetic modification, Miscellaneous, Science, Science and society, science news, SF and science, Sunday Science Stories

Sunday Science 01/10/17

Here is the this week’s Sunday Science, including truly wearable tech, tsunami-borne sea creatures and duck penises.

Do you have one of those smartwatches which measures your heart rate when you exercise? Does your smartphone automatically keep track of how many steps you take each day. Well, the future both for this and for medical monitoring may lie more in flexible, wearable sensors, or the bodynet, as this fascinating piece in Nature of the latest merging of scifi with science fact explores.

Male ruddy ducks regenerate their penis every year, apparently, one of those glorious facts you never knew you needed in your life. However, they may grow an extra-long (as in, 18cm!) or an extra-short one (only 0.5cm), due to fierce sexual competition.

Salmon have returned to a river in Derbyshire for the first time since the Industrial Revolution.

Continuing the CRISPR revolution, it has been used to genetically engineer human embryos to study early embryo development, revealing an important role for a gene in embryo implantation and miscarriage risk.

This week’s featured image is of marine sea slugs from a Japanese vessel from Iwate Prefecture, washed ashore in Oregon in April 2015 [Image credit Mark Chapman via Science Daily]. Thousands of creatures were washed across the ocean as a consequence of the Japanese tsunami, a study published in Science magazine discovered. Such “rafting” events are natural, of course, but what’s not natural is the extent of this migration, much of which was enabled by animals riding along on our non-degradable plastic waste. Nearly 300 species have appeared on the west coast of the US and Hawaii. This is potentially setting in motion a radical ecological experiment.

biology, evolution, Science

CCR5 delta 32: the story of a gene, a mutation, and two of the worst diseases in human history

During the 1980s, there was widespread fear of the AIDS epidemic that was sweeping Northern Europe and America. I was a young child at the time and don’t remember much about it, but by the 1990s my fellow teenagers and I were certainly very well aware of this terrible disease and the importance of safe sexual practices. It seems rather strange (and alarming) to me that there is a whole generation of people here who have grown up without that spectre hanging over them. Modern treatment for HIV, the virus that causes AIDS, has transformed it from a certain death sentence to a something that, with combination antiviral therapy, can be lived with for (so far) a normal lifespan. This is a scientific triumph. The story in less wealthy countries of the world, particularly the ongoing pandemic in Africa, is far less rosy, with a million people worldwide dying of the disease last year.

During those turbulent times, stories emerged of people – usually European or American homosexual men, who were the main victims among those populations at that time – who never got the disease, despite repeated exposure. Of course, it’s usually the case that there are resistant individuals to diseases in human populations, but this was a brand new disease spreading, and mutating, incredibly rapidly. Whatever was different about their genes, it was present at their birth, long before the pandemic started. What was this genetic change that meant they could survive what was then unsurvivable, and even not to catch it all?  Continue reading

biology, evolution, Miscellaneous, News, Science, science news

Sunday science 27/08/17

A mixed bag for this week’s Sunday science, with dinosaurs, microbes, toilets and, er, voters (today’s challenge: put those four things in a sentence that makes sense!).

The featured image is an artist’s impression* of three dinosaurs in a new fossil that were found huddled together, possibly for warmth. They may have engaged in “communal roosting” like some bird species.

Hotter weather is known to increase incidents of violence. Now it seems it can influence voter behaviour (link to original research article). I find it somewhat ironic that Al Gore, famous for his work warning on climate change, might have won the 2000 presidential election if it had been just 1C hotter in Florida that day.

A technical one for the microbiologists. Sequencing of microbe DNA fragments in human blood has revealed that hundreds of unidentified species that live on or in us.

Finally, a weird one from Science Daily in July: mixed sex toilets reduce queuing time. I’m fascinated by this primarily because there are people in existence who are “queueing theorists.” Can you imagine the “So what do you do for a living conversation?”

*Illustration by Mike Skrepnick for Nature.

biology, evolution, medicine, Science, Science and society, science news

Sunday Science Stories 19/08/17

I’ve got a regular post in the works, but for now here’s the weekly round-up of some selected science stories you may have missed in the mainstream press.

There’s been quite a lot of controversy about the use of AI lately, because the problems of it incorporating our own biases (notably racism and sexism) because the data we feed it is biased. Fortunately, some things are hard to bias. AI can be used to successfully identify plant species.

This story is something we should all know anyway, but it’s nice to have some empirical proof: Choosing “alternative” medicine makes you more likely to die from cancer. That’d be because it doesn’t work. The link is to a New Scientist short piece as the original paper is paywalled.

This is a long and slightly technical but fascinating report into the benefits of working on non-model organisms, i.e. those which haven’t been used traditionally for decades in scientific research, such as mice. They may not necessarily be as easy to work with, because of the lack of genetic tools available in particular (although CRISPR/Cas9 is changing that) but they can yield invaluable knowledge and medicines. Examples given here include a treatment for diabetes from the gila monster, and anti-coagulants from the vampire bat. Unfortunately it’s not open access, but I wanted to flag it up for those of my readers who have institutional access as it’s a great overview.

Another long and slightly technical one, but free for all and highly interesting. Can animal culture drive evolution? The main example is that of orca hunting strategies (pictured) and song in birds: can different animal cultures lead to speciation? It’s a compelling and controversial idea that is gaining some traction (not least because it was once thought only humans had “culture”). This is something for the science fiction writers to think about as well.

Finally, something to digest: historically, millets used to be an important human food source. They may now be a food for the future, building resilience and diversity into our food supply.

 

biology, evolution, Science, science news

Human evolution continues to get more complicated

A good, if slightly technical article in the Guardian today here, about the ever-contentious split between modern humans (Homo sapiens) and Neanderthals. The evidence for interbreeding between humans and Neanderthals added up quite convincingly after the initial surprise discovery, probably shortly after the “Out of Africa” migration around 75,000 years ago. This article reports on results from sequencing mitochondrial DNA, which is only transmitted through the female line, suggesting there was some interbreeding between 413,000-270,000 years ago, a staggeringly long time ago. This is way before the main migration out of Africa by modern humans, and not that long after the split between the Neanderthal and Homo sapiens lineages from their common ancestor around 500,000 years ago. It seems that there may have been smaller migrations before our species successfully established itself outside of Africa.

I’ve written about human evolution before here, which gives an overview of some of the more recent findings about our relationships with other hominids. This new finding really strikes me again how migration is a defining feature of our species; it may well have been so for other hominids too. Maybe this is why our ancient relationships are just as mixed up as our modern ones.

evolution, Miscellaneous, Science and society

Humans: born to…migrate?

Following on from that Nature feature on human migration I blogged about  a couple of weeks ago, is another interesting piece in Science provocatively titled: “Busting myths of origin.” It is, however, exactly as the title says: analysis of DNA and isotopes in bones and teeth is showing that most of the people of the world are the products of multiple migrations: there are no “pure” peoples of any kind, with the exception of a very few groups, notably the indigenous Australian Aborigines, who, largely through accidents of geography and circumstance, remained isolated from many other human groups for a relatively long time. Migration and mingling, it turns out, is the norm for our species.

Continue reading