Saturday, March 21, 2009
Tuesday, March 17, 2009
I had so much fun with the kids last week for science week -- I was asked to come teach the Key Stage One kids (reception to Y2, 4-8 year olds) something science-y and I settled finally on ANTS, using my experiences with the Discovery Park curriculum and adapting it for this gang. I may have had more fun than the kids in fact, but now they all know me as the ANTS teacher and they keep telling me how they are all studying ants at home. One 5 year old even announced that maybe, just maybe, he would be a scientists one day. I was both surprised by and impressed with their enthusiasm for the subject. One of Owen's classmates who is kind of...um, naughty....decided as he observed the anthill that he was going to be the "champion for the ants" and look after them. He even brought some apple from his lunch for them "because they need to be healthy and strong!" The kids especially enjoyed their 'field research' and spent their recess at the anthill watching after 'their' anthill and trying to track a single ant along it's journey to and from the anthill. (photo above) They even brought their teacher out to the anthill after class.
"It is well known that ants do not respond to sound on a human scale. You can shout at an ant and it doesn't seem to notice. Yet many ant species communicate by means of squeaking sounds from a stridulatory organ on the ant's body, consisting of a washboard-like set of ridges and a scraper. The squeaking sounds are usually very faint but they pervade ant colonies. Sounds from individual ants can be heard distinctly and there are a number of different signals. The sounds are in the audible frequency range around 1kHz. Because ants appear to be deaf to airborne sound on a human scale, myrmecologists have inferred that they transmit stridulation signals through the soil, or other solid substrate. For a number of reasons, however, this mode of transmission is highly unlikely. A more likely explanation is that ants communicate with each other through the air using nearfield sound. As with other insects, ants are believed to "hear" airborne sound with their antennae, using hair-like sensors at the tips. By sensing the relative difference in sound displacement between the tips of the antennae, an ant can detect a stridulation signal in the nearfield, where displacement changes rapidly with distance, but can not detect sound in the farfield, where displacement changes more gradually. This explains how ants can detect sound from other ants while, at the same time, being unaware of sound on a human scale. This is fortunate for ants because they would otherwise be overwhelmed by background noise, both natural and man-made."