Monday Science Links

This week's yummy science:

• Ed at Not Exactly Rocket Science talks about the intelligence of corvids: Aesop's fable "The Crow and the Pitcher" has been confirmed in a wonderful experiment. In the classic tale, a thirsty crow uses stones to raise the level of water in a pitcher until it rises within reach of its beak. This is no mere fiction - rooks, close relatives of crows, have the brains to actually do this.


• Mo at Neurophilosophy has more on corvids - video of crows and the rooks: Not so long ago, the idea that birds might possess some form of what we call intelligence seemed quite ridiculous.Yet in recent years, this view has changed dramatically, with numerous studies showing that some bird species are capable of complex cognition. Members of one family of birds in particular - the Corvidae, which includes crows, rooks and ravens - have an ability to make and use tools which is at least as sophisticated as that of chimpanzees. Two new studies, published this week, provide yet more demonstrations of the remarkable cognitive abilities of this group of birds. One shows that Caledonian crows can use up to three tools in sequence to obtain food, the other that rooks can use stones to raise the level of water in a vessel in order to bring a floating worm into reach.


• Judith at Zenobia: Empress of the East talks about the dog days of summer: The Dog Days originally were the days when Sirius, the Dog Star, rose just before or at the same time as sunrise -- which no longer happens due to the procession of the equinoxes. But it is still the hottest, driest time of year in most of the northern hemisphere, a time of torrid, sultry weather, when bloggers slow down or even stop blogging. Sirius is the brightest star in Canis Major and rose and set with the sun in summer, roughly from 20th July to mid-August. The star is so bright that, under the right conditions, it can be seen by the naked eye even in daylight. The Greeks believed that the heat of late summer was actually caused by the appearance of Sirius and called this period the days 'under [the] Dog' (hupò Kúna). To Hesiod (Works & Days, 8th C BC), the star brought the enervating heat that led to inactivity and lethargy in men (when men are feeblest) but women -- ever devious -- were at their most wanton and ran riot. Four hundred years later, the Latin poet Aratus (ca. 310-260 BC), depicted Sirius as bringing a dangerous scorching heat that burns and wilts the crops. It was bad for humans, too. Sirius produced 'emanations', you see, which placed people and animals in dire danger. The star shot out flaming tongues of fire and deadly fevers. People who suffered from its heat were said to be 'struck by the star' (astrobóletus). The Romans believed that Sirius was adding heat along with the sun to make it super-hot, thus scorching the earth. And thus, Sirius and the "Big Dog" constellation (Canis Major) came together with the hottest summer days, called the caniculares dies, the days of the dog star (in Latin Canicula), and we still use the same phrase. But Sirius was not a nice doggy.


• Jennifer at Twisted Physics talks about an often-overlooked side of the Moon landing Can everyone stomach one last moon landing post after the media deluge of last month? I hope so, because I've just stumbled on this most excellent bloggy rumination by Carlos Hotta of Brazillion Thoughts, a recent addition to the SEED Science Blogs family. Hotta muses on the difficulties we mere humans face in grasping the sheer distance and dimensions of our moon, and translates the size scale into an unusual metric: pixels. But then he moves on to ponder the terrible loneliness of one Michael Collins, better known as the forgotten astronaut in that historical moon landing 40 years ago. Collins was the unlucky dude who had to stay behind on the spacecraft while Armstrong and Aldrin made history -- orbiting around and around all by himself until the moon walk mission was completed. Collins produced a written record of his isolation.


• Ethan at Starts With A Bang on just how old dirt is, anyway: Every once in awhile, a question makes it to my inbox that's too good to ignore. 'A friend and I were joking about being "older than dirt" and he asked a question I thought you might enjoy: "Hey, ask Ethan how old dirt is and how it got here."' You did the smart thing by coming to me, because the alternative is to ask yahoo. (Shudder!) Well, right away, we've got an upper limit, because the entire Solar System is only about 4.5 billion years old.

Enjoy!