Sex. They had to be fighting for mates!
He became so excited he twitched a foot slightly. Two more pigs dropped dead, but the others paid no heed.
He watched the lazily milling herd intently, at the same time keeping an eye out for the flying whales. Back on Earth porpoises had been taught to herd schools of fish and of whales. It was not impossible an intelligent species of whale had learned to herd masses of land animals.
But Ekstrohm knew he needed proof. He had to have something to link the pseudo-death of the wart-hogs to the inexplicable presence of the whales. Perhaps, he thought, the "death" of the pigs was the whales' way of putting them into cold storage—a method of making the meat seem unattractive to other animals, on a world perhaps without carrion scavengers....
Something was stirring among the pigs.
One under-sized beastie was pawing the dirt, a red eye set on the fattest animal in sight. Then Shortie charged Fatso. But abruptly a large raw-boned critter was in Shortie's path, barring him from Fatso.
Faced by Big Boy, Shortie trembled with rage and went into a terrible temper tantrum, rolling on the ground, pawing it in frenzy, squealing in maddened rage. Then Shortie was on his feet, desperate determination showing in every line of his body. With heedless, desperate, foolhardy courage he charged Big Boy.
Big Boy took the headlong charge in his side with only a trifling grunt.
Shortie bounced ten feet in the light gravity, and grimly wallowed to his feet. He leveled an eye at Big Boy, and his legs were pumping in frenzied fury again.