The next time you watch a snowfall, just think that among the falling flakes are some that house bacteria at their core.
It’s a well known fact that water freezes at 0°C, but it only does so without assistance at -40°C or colder. At higher temperatures, it needs help and relies on microscopic particles to provide a core around which water molecules can clump and crystallise. These particles act as seeds for condensation and they are rather dramatically known as “ice nucleators”.
Dust and soot are reasonable ice nucleators but they are completely surpassed by bacteria, which can kick-start the freezing process at higher temperatures of around -2°C.
Chimpanzees may not be able to recite Hamlet or giving rousing speeches but there is no doubt that they are excellent communicators. They exchange a wide variety of sophisticated calls and gestures that carry meaning and can be tailored to different audiences.
The sophistication of chimp communication doesn’t stop there. Jared Taglialatela from the Yerkes National Primate Research Center has found that chimp signals and human speech are both strongly influenced by the same area in the left half of the brain – a region called the inferior frontal gyrus (IFG).
Male insects have a tough time of it. Aside from the usual threats of predators, competitors and the odd hungry female, many are plagued by discriminatory parasites intent on killing them, while leaving their female peers unharmed. These “male-killers” are incredibly successful and infect a wide range of insects, who are themselves a very successful group. One of these killers, a bacteria known as Wolbachia, may well be the world’s most successful parasite.
The male-killers are paragons of selfishness. Their success hinges on successfully infecting females, for whithin egg cells, they find easy passage into the next generation. But they can’t infect sperm and as a result, males are useless to them; a reproductive cul-de-sac that they can afford to do away with. At worst, eliminating males from a host population does the parasites no harm and at best, it provides the surviving female siblings with fewer competitors and even a potential source of food.
Humans have explored the entire face of the planet, but we haven’t done so alone. Animals and plants came along for the ride, some as passengers and other as stowaways. Today, these hitchhikers pose one of the greatest threats to the planet’s biodiversity, by ousting and outcompeting local species.
Islands are particularly vulnerable to invaders. Cut off from the mainland, island-dwellers often evolve in the absence of predators and competitors, and are prone to developing traits that make them easy pickings for invaders, like docile natures or flightlessness.
Two years ago, I wrote about the ability of invasive predators to change entire island landscapes. In the Aleutian archipelago that runs between Alaska and Russia, Arctic foxes have turned some islands from grassland to tundra by killing the seabirds whose droppings provided the islands’ only fertiliser.
Now, we return to the ill-fated Aleutians to discuss another study that shows how the actions of immigrant predators can even domino into the surrounding waters. This time, the stars are not foxes, but that other ubiquitous opportunist – the brown rat.
Not Exactly Rocket Science has now officially transformed and rolled out into the ScienceBlogs network. So to readers who have tracked me here, new Not-Exactly-Rocket-Science virgins, my new SciBlings, and people who have mistakenly stumbled here during their search for porn – hello! The blog is about explaining new research in a way that anyone can understand, regardless of their scientific background. I generally post about 3 times a week and more if time permits.
Also, I’m giving a talk on science blogging this Thursday at London’s Apple Store on Regent Street, alongside Jennifer Rohn who runs LabLit and Mind the Gap, and Ben Goldacre, who writes the Guardian’s infamous Bad Science column and the associated blog. If any of you are in London and fancy rocking up, then please do.
Details as follows:
Thursday 28 February 2008
What is it like to work in a lab? What’s the latest science news? How can you tell good science from quackery? The answers to all these questions can be found in blogs, and in this event you’ll meet the people who are writing them.
There are literally tens of millions of blogs online. Some read like personal diaries, while others are built round news or analysis, like reading a column in a newspaper. With so many blogs out there, it’s no surprise that science is well-covered from lots of different angles. Ben Goldacre goes on the hunt for outrageous claims, dubious statistics and credulous science reporting in Bad Science, an extension of his popular column in the Guardian. Jennifer Rohn reveals the culture and everyday life of a jobbing scientist in her blog on Nature Network London, Mind the Gap. In Ed Yong’s blog, Not Exactly Rocket Science, he converts plodding, jargon-heavy journal papers into nimble, accessible and entertaining blog posts on the freshest new research.
Join us as our bloggers talk about why they write, what makes a good post, and what blogging can do for science. You’ll come out of it with three personal views of science and some good new reads, and best of all, the event is free!
Venue: The Apple Store, 235 Regent Street, London W1B 2ET
Admission is free and there is no need to book.
In association with Nature Network London