Parasites are thought to diversify with their host species, but the theory has rarely been tested. Kevin Johnson at the University of Illinois and his colleagues sequenced the genomes of 46 species of lice that parasitise birds or mammals, and two non-parasitic bark lice, and constructed an evolutionary tree. They estimated that parasitic lice first emerged between 90 and 100 million years ago, but didn’t begin to diversify until 66 million years ago – around the time of the dinosaurs’ extinction.
As I’ve mentioned before, living in a large densely-packed social group, like a city or an ant colony, comes with some drawbacks – perhaps worst of which is the risk of catching a contagious diseases. Earlier this year I wrote about research showing that raider ants treat injured workers’ wounds, helping them to heal. Now, a new study shows that the queen can pass on resistance to diseases she’s encountered, arming her workers against pathogens.
I’ve spent more time than most observing ants, and I’ve come to find them ‘cute’ – something few other people understand, and that is often hard to convey. So it’s nice to find a paper that offers the opportunity to give people a glimpse into the cuteness I see in ant behaviour.
Ants clean the wounds of injured nest mates, often saving their lives and keeping infection out of the colony.
I’d like to talk about a very important issue, very close to my heart, and one that I think needs greater public awareness – the definition of the word ‘bug’.
See, people think they can just throw the word bug around willy-nilly. Anything small, flying or irritating, is a bug. Any pest, is a bug. But what many people don’t realise is the word isn’t just a colloquial term for insect or invertebrate, it isn’t a synonym for shelled or armoured creatures, it has a real scientific definition.
The word bug refers to insects in one particular order – Hemiptera, or the True Bugs.
What are the effects of yoga and meditation on the brain? (Asked by @leximills)
Yoga and meditation have effects on physiology, brain chemistry, and cognitive processes; these vary depending on the exact type of practise being performed and how long a person has practised it for. Studies of brain activity confirm that meditation can achieve a state of calm, thoughtless awareness, by suppressing brain regions involved in external attention and irrelevant information, and activating brain regions involved in internalised attention and positive emotions. Meditation is thought to activate the parasympathetic-limbic pathways, reducing heart rate, lowering blood pressure and slowing breathing. Meditation practises can fundamentally change the shape, structure and function of the brain – reinforcing neural networks, developing particular brain regions and influencing the production of key neurotransmitters and hormones in the brain related to attention, self-awareness and emotional control. Yoga has far-reaching effects on the body, reducing inflammation, boosting mood and making long-term practitioners feel more awake. It may even speed up learning in childhood and slow the natural cognitive declines that come with ageing. However, our understanding of the effects of meditative practises on the brain and body is still in its infancy – much more work remains (especially large-scale, carefully controlled trials).
A guest post for Curious Meerkat by Emily Folk.
Have you ever considered a world without elephants? This is a world we’re heading toward with the profound level of poaching that has occurred. As a result of almost institutionalized poaching over many decades, we have decimated the population of wild African elephants to between 400,000 and 600,000 individuals.
The Ig Nobel Prizes is one of my favourite events of the year, and this year the winning research is particularly great. On the 14th September, The 27th First Annual Ig® Nobel Prize Ceremony & Lectures took place at Harvard University in Massachusetts. In case you’re not familiar with the awards, they were set up in 1991 to celebrate research that makes you laugh, and then makes you think. Here are this year’s awards:
I’d like to talk about a problem. It might seem like quite a small problem, but it’s a pervasive one. That problem, is salad.
Yes, that’s right, I said salad. Not high on the list of major world perils, but perhaps it should be. I mean, for starters, it’s everwhere. Lurking in every supermarket-bought sandwich, mocking you from the side of every pub lunch, withering beneath every take-away spring roll. And that sad bit of salad that came with your meal, that you never even for a moment considered eating, has caused a surprising amount of damage to the environment.
Can bees only sting me once?
Honeybees are generally killed by stinging you, but most other stinging insects can survive to sting you again.
It’s a common urban myth that bees can only sting once, but it’s partially based in truth. Honeybees have a barbed stinger, and if they sting a thick-skinned mammal like a human, the barbed hook gets stuck as they try to pull away, ripping their insides out and killing the bee within a few minutes. But if they were to sting another insect, or a vertebrate with thinner skin, they’d probably live to tell the tale.
New gene editing technologies have revolutionised genetic science, but social insects like ants have proved difficult to genetically modify because of their complex lifecycle and social structure. Now, two separate labs have succeeded in using the CRISPR-CAS9 system to genetically modify two unusual ant species, switching off genes and disrupting their social behaviour in the process.