Our science stories this week included everything from ancient cannabis to killer shrimps, a spike in elephant poaching and an encounter with wolves.
Here’s a snapshot of a few stories we particularly enjoyed. Click on the links to read them in full. You can also see all the week’s yarns here.
Killer shrimps wreak havoc through terror
The fear of invasive “killer shrimps” can stop native organisms fulfilling their vital role in river ecosystems, new research shows.
Even if the predatory shrimps do not attack, their mere presence is enough to debilitate other species. And this fear is already having an impact in Europe’s rivers.
Read the full story here.
The next step in antenna design
Carbon nanotubes represent an appealing alternative to copper for the manufacture of antennas for wireless devices, researchers say.
A team led by Amram Bengio from Rice University in the US have been experimenting with metal-free antennas, made from single-walled carbon nanotubes dissolved in acid and then smeared onto a surface.
Read the full story here.
Encounters with wolves
If wild wolves lose their fear of humans the result, all too often, is that they are declared dangerous and killed.
I’m in a boat off an island off another island, and I’ve just spotted a wolf.
At first it’s just a grey-white blur against sand, but as our zodiac swerves towards the island’s coast, the ghostly figure becomes visible, climbing up onto jagged rocks to scour the high tide line for food.
Read the full story here.
High times: evidence suggests cannabis smoking emerged around 500 BCE
Organic material extracted from fragments of ancient wooden burners and stones excavated from a 2500-year-old western Chinese cemetery has produced some of the earliest evidence of ritual cannabis smoking.
Read the full story here.
ET ‘habitable zone’ much smaller than previously thought
A large number of extrasolar planets that otherwise lie in a star’s “habitable zone” may have poisonous atmospheres, scientists say, in a finding that may greatly limit the number of exoplanets habitable to life more complex than microbes.
Read the full story here.
Elephant poaching spikes in Botswana, endangering the species
A new study has found that poaching of African elephants (Loxodonta africana) for ivory has escalated in northern Botswana, a region that was previously one of the safest for the animals.
Read the full story here.
And here’s our image of the week
NGC 7773, as seen by Hubble: spiral, mature and barred.
It’s difficult to know what your home looks like if you don’t, or can’t, leave it.
Take the Milky Way, for instance. Astronomers think it is a barred spiral galaxy, a bit like this one, which is called NGC 7773, which is about 392 million light years away. They can’t be sure, though, mainly because no human-made imaging vessel has thus far escaped the galaxy, turned around and taken a snap.
This image of NGC 7773, taken by NASA/ESA Hubble Space Telescope’s Wide Field Camera 3 (WFC3), reveals the existence of a series of luminous bars – they appear orangey-brown in this instance.
Astronomers think that the bars develop as galaxies mature, and comprise star-forming material slowly being pulled into the centre of the system.
The Milky Way is a spiral, and quite old, as galaxies go, so it is reasonable to suspect it also contains bars. It might be a very long time indeed, however, before the photographic material exists to prove the contention.
To view all this week’s featured images, click here.