ON GIANT EGG herring gull teeters uncertainly trying to keep from slipping 
off. Finally the gull gave up and settled down on the small egg alongside. 
GULL’S BIRDBRAINED ENDEAVOR 
The herring gull shown on page 70 reached a decision quickly. Ignor¬ 
ing the normal-sized wooden egg, the bird gamely struggled aboard the 
monster egg {above). This incident was illuminating to Gerard Baer- 
ends, professor of zoology at Holland’s Groningen State University, 
because it proved that an object needs to have only faint resemblance 
to a real egg for a herring gull to do its unintelligent best to hatch it, 
even in preference to an egg of proper size. 
Professor Baerends made the wooden egg experiment this year on 
Terschelling Island in the North Sea. His experiments have taught 
him other things about herring gulls. To fool them he made eggs of 
different shapes and colors {below), and placed some of them on the 
edge of a nest and waited to see which the gull would drag in. Herring 
gulls, he found, are usually bored by plain eggs. But if the egg is speck¬ 
led, the bird will try to hatch it, even when it is square {next page). 
EGG ARSENAL, spread before Baerends, includes glass egg {left, on paper) 
invisible to gull, but which it will try to hatch when it feels egg with its body. 
