The Flight of a Falcon

An oblique view of the flight-track of a peregrine falcon taken from the paper "Comparing bird and human soaring strategies" by Zsuzsa Akos, Mate Nagy, and Tamas Vicsek (Proc Natl Acad Sci USA, 105, 4139-4143, 2008.  arXiv:0902.0312v1 [physics.bio-ph]).  The altitude and location of the bird were tracked by fitting it with a miniaturized GPS device.  The red and yellow parts of the track correspond to when the bird was climbing (mostly on thermals), and the blue parts to when the bird was falling (gliding).  The grey background is a satellite image of the terrain.

Animal Training

From an old article by Amy Sutherland in the New York Times:

The central lesson I learned from exotic animal trainers is that I should reward behavior I like and ignore behavior I don't.  After all, you don't get a sea lion to balance a ball on the end of its nose by nagging.  The same goes for the American husband.

Read the whole thing here.

Swarm

Earlier this afternoon, I was sitting reading on the sofa in our living room.  The window was open and the sunshine was streaming in.  The book I was reading was The Master and Margarita by Mikhail Bulgakov.  I had to get up once to guide a bluebottle fly out out of the window, but soon got back into the book.  A bit later I slowly became aware of a buzzing sound, like that of a wasp, but not quite right: too even in volume.  Then I realized: not a single wasp but lots of them!  I jumped up to look out the window.  There were thousands of wasps in the air, orbiting each other like a cloud of giant midges.  I rushed round the flat closing all the windows (probably unnecessarily, as they didn't seem to be interested in coming indoors).  Slowly, they rose up and moved over our flat roof, and I watched from the kitchen window as they drifted off towards a tree near the main road.  The swarm was about 3 to 5 metres in diameter, with occasional members much further away.  I last saw them above the path beside the road.  Strangely enough, people walking along the path didn't seem to notice them at all.

Not so much Fly as Plummet...

A Pythonesque tree-climbing goat of Morocco.  Apparently these goats like the fruit of the Argan tree.  More details here.  A Flickr photo by K. Horn

'Tis the Season to be Arachnophobic

I always think of early September as the time of year that the spiders start coming down the windows in the evenings.  During the day they skulk in the corners of their webs but in the evening they move out onto their webs to await the flies and moths.  I am not sure whether the spiders are using that fact that insects are attracted by the lights in windows: there do not seem to be noticably more spiders outside our living-room, which is usually well-lit, when compared to our bedrooms which are relatively rarely lit.  However, I have seen lights in an underpass downtown that were completely covered by a mass of webs, studded with the bodies of snared insects as if the spiders were catching far more food than they could deal with.  There the lights were fluorescent and were left on all night.